V I T A M I N S

A CRITICAL SURVEY OF T H E T H E O R Y

OF ACCESSORY F O O D FACTORS

BY

R A G N A R B E R GDIRECTOR OF THE LABORATORY OF PHY8IOL0GICAL CHEMISTRY

AT WEI88ER HIRSCK

TRANSLATED FROM TK(E GERMAN BY

E D E N A N D C E D A R P A U L

L O N D O N : GEORGE A L L E N & U N W I N LTJP

RUSKIN HOUSE, 40 MUSEUM STREET f £ '

T A B L E O F C O N T E N T S

PAGETRANSLATORS' PREFACE 9

CHAPTER# I . INTRODUCTORY 17

II. THE BIOLOGICAL VALUE OF THE VARIOUS PROTEINS . . 29

1. The biological Value of the Amino-acids . . . 292. The Relationship of the pr6teid to the non-proteid

nutritive Substances . . > . . . - 3 73. The Importance1 of inorganic Constituents in Metabolism 404. The biological Value of the various vegetable Proteins . 415. The biological Value of the animal Proteins . 526. The Conditions requisite for the full Efficiency of the various

Kinds of Protein . . . . . . . 58

III. THE IMPORTANCE OF INORGANIC SUBSTANCES . . . * 6k

1. The Supply of a Sufficiency of nutritive Salts . . $22. The Importance of individual inorganic Substances . 673. The Importance of an Excess of alkaline Substances . 704. Acidosis . . . . . . . . . 765. Paradoxical Effect of Calcium Salts in the Organism . 836. The Administration of Alkalies as a Preventive of Acidosis 877. Forms of Combination of inorganic Substances ; their Mode

of Action 888. Mutual Interdependence of the inorganic Substances . 909. The UtiKsation of Calcium in various Forms of Administra-

tion 92fb. The Effect of Oxidation upon the biological Value of the

Acid-formeis . . . . . . . . 94

IV. BBRIBBRI AND OTHER FORMS OF POLYNBURITTS . . . 100

1. Etiology , 1002. Isolation of Vitamin . n o3. The Properties of Funk's Vitamins . - . . 1164. Occurrence of the Vitamins • . 124

6

CHAl'lF.N

5-

6.

T h ea.b.

c.

V I T A M I N S

C o n n r q u f n c r « t4 an tn*nU*ii**i

Cl i nit «it

i\itht>lt'#i(-«ilT h e I* ox mil

A n a l y s i s <*f t h f

a.

h.

c.

Signifit MKvFttvi t s of I'

I hth tviu r i 1th . i t id v.*i

! A«at< »«v .id ih<* 1 »1 P J i r

HU^tii^I Af lUlt*" t *tlfi( th« N u n j I ,n,

u t i k S Vtfdistiifn

ijrtvtt« JJ th*- I J^* 1

i>trt i hiljlr Jl * r I t

f - # i

«. Ikhavjrnar of th*1 UhttvU .

SUte» < **7. Karltrr Attempts nl Lxj4*«i4l« u • * -8. Summary . . . . . f ' "

V. THE CONDITION.** 01?t. Introductory . *;#2. Importanct} «f IV«4rm . . ***«3. Importuner4. Xm|>ortanu*5. The fat*nuluUi < i#m|>Irtim A **#6. The

ti* r»l ISc. OTi;uitit,iltvr I

«. Phyjiioli»giral MtetU ut tUr i>um%h*tmn^htUn I* iv*

7* Behaviour c»f th** Friii*i* rmr f#l.f?i*Iji , #*»#S. Importance ol thr* Nwintinn t*l tb* M^ihrf . #«*i9. Effect of tijc* Ifshtbtti fi c#! (,tuwtU ui*m m%mmi%mi Untrmih §> ;

10. Summary . , $*t4Addeadum to Chapter kmtf ' H|#mr , $ $ #

a* Clinical Picture , t##b. Pathological AtmUmiy , i#l«. Fmgnoili , * #t#&. Treatmentt , , # # l0. Etiology . i # |

VI. THB tAT-SCttJBJL« COMfUlfTIM A . f ##

1. History; its luxation . i t #

2. Occurrence . . . . . . i # #

S» C^apkttto A and Upocltroi^ . , i f #

CONTENTS 7

CHAPTER PAGK

4. Relationship to other Complettins . . . . 2 2 65. Properties of the Complettin A . . . . 2276. Physiological Action of the fat-soluble Complettin A . 2307. A in relation to Xerophthalmia and to Keratomalacia

respectively 2318. A in relation to Osteomalacia 2339. A in relation to Rickets . . . . . . 235

10. A in relation to Pellagra , . . . . . 2 3 8ir. A in relation to malnutritional Oedema . . . 2 3 812. Action upon the endocrine Glands . . . . 2 3 9

VII. THE ANTISCORBUTIC COMPLETTIN C 242

1. Historical . . . . . . . . . 242* 2. Scurvy Epidemics during recent Years . . . . 247

3. Occurrence of the antiscorbutic water-soluble C . 2 5 1a. Occurrence . . . . . . . . 251b. Natural Variations in C content . . . . 2 5 3c. lEffect of Germination upon the C content of Seeds . 255

4. Properties of the Complettin C . . . . . 2565. Composition of the antiscorbutic Complettin C. . . 2626. The physiological Consequences of C deficiency . . 265

a. Clinical Picture . . . . . . . 2 6 5b. Pathological Anatomy . . . . . . 266c. Reciprocal Relationships between C and inorganic

Substances 268d. Forms of Purpura in relation to C deficiency . . 269

6. Mode of Action of the antiscorbutic Complettin . . 269

VIII. MALNUTRITIONAL OEDEMA 27*

1. Clinical Picture 2712. Pathological Anatomy 2733. Prognosis 2744. Metabolism 275

a. Nitrogenous Metabolism 275b. Sodium-Chloride Metabolism 275

5. Dietetic Factors of the Disease 277a. The pathogenic Diet 277

* b. Wartime Feeding ' 278c. Prison Dropsy 279d. Ship Beriberi 279

6. Contributory Causes of Malnutritional Oedema . . 281a. Microorganisms 281b. Inadequate Supply of Energy . . . . 2 8 1c. Complettin Deficiency 282d. MalniitritioEal Oedema akin to Mehlnahrschadei* . 284

8 VITAMINS

CHAPTER PAGE7. Causes of Dropsy . . . . . . . 284

a. Chemical Causes 284b. Cholesterin Impoverishment . . • . . 2 8 5c. Anomalies of inorganic Metabolism . . . 2 8 7d. Effect of Hydraemia 288e. Cardiac Asthenia 289/. Behaviour of the Kidneys . . . . . 289g. The Effect of the various Ions on the Kidneys . 290h. The Reduction of Blood-pressure . . . . 292i. The Effect of B deficiency 292k. The Lack of Potassium and Calcium . . . 2 9 3

8. Summary . . . . . . . . . 293Addendum to Chapter Eight: Kindred Nutritive Disorders 295

a. Mehlnahrschaden . . . . . . . 295b. Milchnahrschaden . . . . . . $97c. Fat as a noxious Factor in Infant Feeding . . 2 9 7

IX. PELLAGRA 2991. Clinical Picture . . . . . . . . 2992. Pathological Anatomy 3013. The Pellagrogenic Diet . . . . . . 3044. Views that have hitherto prevailed concerning the Etiology

of Pellagra . . . . . . . . 306a. Microorganisms as the Cause . . . . 306b. The Effect of the colouring matter of Maize, known

as Zeochin . . . . . . . 3080. The Effect of the Maize Toxin . . . . 3 1 0d. The Inadequacy of Maize Protein . . . . 3 1 2e. North-American Experience . . . . - 3 1 3/. Specific Importance of Protein Deficiency . . 315g. Pellagra and Malnutritional Oedema . . . 3 1 6h. Vitamin Deficiency . . . . . . 3 1 61. Complettin Deficiency . . . . . . 3 1 6k. The Effect of inorganic Nutrients . . . . 317/. The Effect of Silicic Acid 318m. Mental Influences . . . . . . . . 319n. Complications . . . . . . . 319

5. Summary 320X. CONCLUSION 323

1. Difficulties attendant on modern Experiments conceivingNutrition . . . . . . . . 324

2. The Complettin Content of Foodstuffs , 3263. Nutrition in Complettin Experiments . . . - 3 2 74. The immediate Problems of Complettin Research . - 3 3 65. The Need for State Aid in Experiments on Nutrition . 337

BIBLIOGRAPHY . . . . . . . . . 338

• . ^'~vjf~ *•,„*"*> * • ' - 3 9 1

T R A N S L A T O R S ' P R E F A C E

RAGNAR BERG'S book marks the close of an epoch, the epochduring which the knowledge of vitamins was almost whollyconfined to those who were engaged in the experimentalsttidy of the subject, and the epoch during which the dataof the new science of nutrition were hidden away in the" transactions" of learned societies or scattered almostirrecoverably in the columns of polyglot periodicals. Berghas summarised all this matter within the compass of a singlevolume; has contributed new outlooks; and has provideda platform for the work of future investigators. Incidentally,he has written a book which, though adapted for specialistuse, is anything but abstruse, and cannot fail to be of supremeinterest to the general public—which is awakening to theimportance of vitamins, and is in search of a guide throughthe dietetic labyrinth. There have been several at tempts oflate years to popularise the modern outlooks on dietetics.Notable among those in the English language are Vitamins andthe Choice of Tool, by Violet G. Plimrner and R. H . A. Plirnmer(Longmans, London, 1922), and Vitamincs: essential food

factors, by Benjamin Harrow (second edition, Routledge,London, 1923). Either of these may usefully be read by thelayman and the beginner as an introduction to the t subject,t u t no serious student can afford to ignore Berg's masterlyand comprehensive volume.

O u / quotation of the respective titles of Harrow's andthe Pliramers' books brings up the question of terminology.The word " vitamine" was introduced ten years ago byCasirnir Funk (one of the pioneers in these investigations) fto denote the antineuritic factor discovered and partially 'isolated by him. He chose the name in the belief that thesubstance belonged to the class of chemical compoundi known

i o VITAMINS

as " amines" or " amins." We follow good precedent indropping the mute " e " from the word used as the title ofBerg's book. But this does not solve the difficulty*occasionedby the extension of the term vitamin to denote a whole classof substances most of which certainly contain no nitrogen—whether " Funk 's v i tamin" does so or not. That is whysome authorities prefer to speak of these substances as" accessory food factors/ ' and this name is used in the titleof an excellent governmental publication {Report on the PresentState of Knowledge concerning Accessory Food Factors, H.M.Stationery Office, 1921). But the proposed name is worsethan cumbrous; it is vague; it might just as well describethe contents of an ordinary cruet-stand. The vitaminsA, B, C, etc., are doubtless " accessory food factors " ; butso are pepper, salt, and mustard; so is the " roughage"without which we should perish even though our food wereto contain an abundance of proteins, fats, carbohydrates,and salts, together with an overplus of vitamins. RagnarBerg therefore proposes to restrict the use of the word" v i t a m i n " to Funk's vitamin (or vitamins), and to speakof the general class of substances to which the antineuriticprinciples, the antiscorbutic principles, the growth-factors,etc., respectively belong as the " complettins." Thus thegeneral name for the maladies de carence, the deficiency diseases,is to be, not " avitaminosis," but " acomplettinosis." Andour author is fairly successful in his attempt to be consistentin the use of his own terminology. But it will be noted thatttie title of his book is Vitamins, although the exhaustivechapter on " Beriberi and other forms of Polyneuritis," whichis a detailed study of Athe nature and action of Funk's vitaminor vitamins, occupies only one fifth of the volume.

Here, in fact, as so often, usage rides rough-shod overattempts a t linguistic purism. The picturesque word" vi tamin/ ' as a general term, has come to stay. The*currentemployment of a. word rather than its derivation, or itsdefinition. by a precisian, ultimately decides its meaning.The public imagination has been fired by the idea of thesesubstances so recently discovered, so absolutely essentialto life. In the first syllable of the word " v i t a m i n " thereis an •appeal to a universal effect, to the instincts of

IKW *f \ ink's' WMTV V tr

*r!f p r «-r. *«*< n ^t«l * j * ru r \ |ni*.<*iv.i!itifi. ' lh . i t is why both«. < ** ' i v *>« l t.i» |r»fH " ,MJ*I f t t im ip i t t tm ' * " ait* hk r l y tt>

j i , :nu* * *li\t >n , f h t i i» x\h\ * u u f l j r mv tu fo r *4 tht*Ut t * r ?•:: * !;;. 5. it 4* O M M * ' to «i i f i?ir f i r , bt f tk Vtftnnws !

h ^ tlr % t l* * \» f . a \%iv)«i tt>M tlMin»Vf*nthi> t t t i r tn i | {h t**f f ; j f ' * Ui t * % '*****! I h r .nf i j i ' i f il44ft*"i Hit** <#tllt*r** a t

tK*" « }.'•* '!» ! 0*« .l< f JM|» *4 t!l» J i n - , n | y f*HH] }»M

f « ' ^ !* i* - ! n i .> I I U M I J J I U , i , \%h» $#- I1** i f / , t«tt

r 3^2."* 4** :, . ! > !}»* IM A th ' *« ' l \ r»f f | | r f f t|* » } |4Vr

H i . **w« -JJK «t.tlt v*k h i^^ l^ i innHv til t

till*V lit

#4 #- ^«-itnr<»n " $ti ^*s! What w<" tiavi* tu rtMtr»r H that w rr4.11 ttKikr |Jir " ^iij " i4 tiii

*^i f*r $4 Inn^it jtiif t\ with

J-ift n$4** J*v 'i>*l«* With f f aromjilrttHU^lH** i lf. n *' i l l |r*|tt« t$%g l i t l t |yr»U«| * i | t«"M'4411c «*

mJr-«t$\i- 4K^ni^a ai i ' I l l i n^ wi*hrnf i j v ««*ntf t t iutr^ in

fhr fautty tnrltifi*! ti l

Uf«ltrr ffifttl l« Hu4i thfrli,it!»* m i h i t , t l i r iutMr4) alk'i lmiiy <4 thr UWIITH t4 thtwnmim bviv l4tc r iy «ti vr^^i^Wr% I hit* |»r«-|t.irrtl willUmmM i«» ih«* tUniprr fitstrk I#t itk^r ttutntirr, th^

12 VITAMINS

appears to be a contributory cause of rickets and otherdeficiency diseases.

Another point in which Berg is an innovato* relates tothe number of the vitamins or complettins. Hitherto mostauthorities have spoken of three only. Writing in 1922,Leonard Williams says (Encyclopedia Britannica, twelfthedition, vol. xxxii, p . 931) : " There are probably a greatmany vitamins in natural foods—live or quick foods as theyare called—but up to the time of writing three only havebeen isolated. These a re : (1) the antiscorbutic factor;(2) the water-soluble B ; (3) the fat-soluble A." Only threevitamins are considered by the Plirnmers and by Harrow inthe books already mentioned—although Harrow, in theappendix to his second edition (p. 245), does indeed refer toCasimir Funk's recent contention that " vitamin B is reallya mixture of two vitamins, which he proposes to call vitaminB and vitamin D." Similarly McCarrison, one of the mostnoted investigators in this field, writes as follows in his Studiesin Deficiency Disease- (Henry Frowde and Hodder andStoughton, London, 1921, pp. 244-245) : " I have writtenof three vitamins, because three are known, not because ithas been proved that there are only three. But whetherthere be only three or legion, they will be found to exist—andthis is the important point—in the foods made in nature'slaboratory, in quantities and combinations adequate for thedue digestion and assimilation of the natural foodstuffs withwhich they are associated in nature. The subdivision ofxfrtamins into many classes is not without the risks attendanton decentralisation. Vitamins, like other essential constituentsof the food, are not to be regarded as independent of theassistance derivable from their associates in the maintenanceof nutritional harmony. Each vitamin is but a member ofa team, and the team itself but part of a co-ordinated whole."

Now Ragnar Berg is well aware of the importance of thisconception of team work. (And, like McCarrison, he repeatedlystresses the perpetual interaction between the " t e a m " ofthe vitamins and the •' team " of the various endocrine glandsin maintaining the balance of healthy nutrition.) But hethinks t h a t the time is ripe for a somewhat more elaboratedtffereiftiation of the complettins. Provisionally, therefore,

TRANSLATORS' P R E F A C E 13

he distinguishes five groups. The table showing our presentknowledge of the complettin content of the various foodstuffs(pp. 328-331) is arranged in as many columns. The firstof these deals with vitamins in the narrower sense of theterm, and shows the richness of the different nutrients inFunk's vitamin (or vitamins, for Berg opines tha t they aremultiple), which is the chief antineuritic principle of thefood. Next—though not in the order named—come columnsshowing the quality of the foodstuffs as concerns their richnessin the complettins which, pending their elusive isolation anda determination of their chemical composition, are known byletters of the alphabet: A, fat-soluble, often referred to as theantfrachitic principle; B, water-soluble, whose predominantimportance according to Berg is as growth-factor; C, water-soluble, the antiscorbutic principle; and D, water-soluble,differentiated by Berg both from B and from Funk 's vitaminor vitamins, but like the latter functioning mainly as anantineuritic.

So much for the outlook upon the problem from the pointof view of the substances known as vitamins, complettins, oraccessory food factors. But Berg also considers the topicfully from the point of view of the deficiency diseases. First,of course, comes beriberi with the other forms of polyneuritis,for it was a study of these disorders which initiated the newscience of dietetics. Arrest of growth demands a specialchapter, and as an appendix to this comes a discussion whichthrows a little light on the nature of the still obscure tropicaldisorder known as psilosis or sprue. Scurvy, naturally, hasa chapter to itself. Rickets and osteomalacia, xerophthalmiaand keratomalacia, receive full consideration in the chapter onthe fat-soluble complettin A. The penultimate chapterdeals with various forms of oedema as deficiency diseases,and establishes the substantial identity of the " malnutritionaloedema '* of wartime experience with the " famine dropsy "of India, with " ship berberi," and with " prison dropsy.1'The concluding chapter is devoted to pellagra, and to theauthor's final summary of the whole position of the enquiry atthe date of his writing. How recent this is may be deducedfrom the fact that his bibliography of more than 1,500 entriesis carried well on into 1922, and tha t on pp . 326-327 he Quotes

i 4 VITAMINS

a passage from Sherman and Smith's book The Vitamins,published in New York only last year.

Apart from these " major" ailments which are classed inthe nosology as definite " diseases," Berg's presentation ofthe evidence abundantly confirms the contention of thosedieteticians who hold that an enormous amount of " minor "ill-health is due to what French writers have termed carencefruste or hypocarence. Many, perhaps most of us, suffer,not only iu wartime, but under the comparatively favourableconditions of peace dieting, from what may be termed " larvaldeficiency diseases"—or from the effects of such diseasesduring our infancy and childhood, or from the effect of suchdiseases in our progenitors. On the paper cover of OttoRuhle's book Das proletarische Kind (The Proletarian Child,Langen, Munich, 1922) is a picture of two children who mightbe matched from any slum district of Europe or America.Both have the typical facies of acomplettinosis in childhood.The originals of these portraits would probably be foundto present the stigmata of rickets ; but, short of actual rickets,hypocarence causes stunting of poorer urban children as com-pared with the children of the well-to-do. Yet even thelatter are stunted, thanks to the futility of our " civilised "methods of preparing food. Take, for instance, Berg's state-ment on p . 189, based on the observations of Delf, Aron,Erich Muller, and others, that " in children . . . supposed tobe thriving, to supplement the diet by fresh vegetables, extractof green vegetables, extract of carrots, or extract of bran,could always bring about a further increment of growth.These observations show how defective the nutrition of ourchildreji must be in contemporary life, even under what appearto be favourable conditions."

McCarrison, in especial, has emphasised the importanceof this aspect of the new science of dietetics. He says we must

, always be on the look-out for avitaminosis, thanks to thepestilent way in which we habitually denature our food." I t seems to me tha t * loss of appetite ' is one of the mostfundamental signs of vitaminic deprivation. I t is a pro-tective sign : the first signal of impending disaster. I t shouldat once excite stispicion as to the quality o | the food in anypatieift who may exhibit i t " (op. cit., p. 57),

TRANSLATORS' PREFACE 15

The doctors of an earlier generation, who practised amongthose prone to overfeeding, used to say " we dig our graveswith our teeth." But contemporary diet is just as likely toerr by defect as by excess, and there is equally good reasonto say that the foundations of premature death are laid in theflour-mill and in the kitchen, by the various processes withwhich profit-hunters and ignoramuses spoil our foods. " Fireis a good servant but a bad master/' and man must learn touse fire less on his food and to use it more wisely, if he wishesto enjoy the best of health. Every intelligent reader willdraw his own conclusions as to the practical application ofthe new knowledge to the regulation of his own diet. If asimple formula be requisite, it may be enough to quoteMcCarrison once again (p. 244) : " There are no more importantingredients of a properly constituted diet than raw fruit andvegetables, for they contain vitamins of every class, recognisedand unrecognised." If a crucial example of the sort of thingto avoid be desired, take that cited by Berg (p. 268) fromMcClendon. The craving for fresh nutrients, says McClendon,undoubtedly has a survival value. " Among the Americansoldiers in the trenches, when their rations were restrictedto chocolate, eggs, dried milk, and sugar, worked up into asort of biscuit, he noted that this craving became over-powering within two or three days, and led them to refusetheir rations." (Apparently the idea of the U.S. armyauthorities was that soldiers in the front trenches were likeRobots. " You can feed them on pineapples, straw, whateveryou like. It's all the same to them ! ")

Many of us go through life with no serious risk of ricketsor osteomalacia; we shall not get scurvy unless we visit theSouth Pole or the Klondike; our chance of beriberi or mal-nutritional oedema is infinitesimal. But perhaps most of ussuffer at one time or another from deficiency diseases; perhapsall of us * under extant conditions, are affected during theyears of growth by tares which are wrongly supposed to betares h6r6iitaires9 or due to "weakness of constitution."Many of these troubles are, indeed, due to the follies of ourparents or our parents1 parents; but they are by no meansinstances of " the inheritance of acquired characters," andyet quite as definitely as congenital syphilis they are tases

3 f >

111 t r jf

JI .J4 c I

*»v

V I T A M I N S

CHAPTER ONE

I N T R O D U C T O R Y

F R O M the days of Liebig down to the year 1910, only fourclasses of nutritive substances were recognised: proteins,fats, carbohydrates, and salts. I t is true that Liebig alreadydrew attention to the fact that development cannot run itsnormal course, either in plants, or in animals, should thesupply even of one of the necessary constituents of a completediet be inadequate. The development of living beings is regu-lated by the supply of whichever element is least bountifullyprovided. In a word, this is the " law of the minimum." Sopreponderant, however, is the importance of protein as themain factor in the building up of cell substance, that investi-gators speedily came to overlook all other matters, and toconcentrate upon the supply of protein. Rubner, therefore,took a great step forward when he proved tha t it is not enought o furnish a sufficiency of protein, and tha t our aim must beto provide the body with the requisite modicum of energy.B u t here was a new fundamental principle to monopoliseat tention. As soon as a definite relationship between thenitrogenous and the non-nitrogenous ntitritive elements hadbeen experimentally established, the general belief prevailedt h a t the edifice of the doctrine of nutrition had at least beenfinished in the rough. The various rooms of the structuremight still require decoration, bu t no one anticipated anyfurther extensive additions to the general body of knowledge.

I n this reckoning, the fourth class of nutritive substanceswas, however, entirely overlooked, The inorganic constitu-ents of the food, or, as they are usually named, the nutritive

2 17

18 VITAMINS

salts, had been so much discredited by the unproved assump-tions of unqualified curemongers and quacks and by thepremature practical application of their ungrounded theories,that no one ventured to undertake serious research in thisfield. I myself, more than half a generation ago (instigatedthereto by the pioneer work of my sometime chief, therevered Carl Rose), emphasised the importance of the inor-ganic constituents in nutrition. But whereas people werequite prepared to recognise that the law of the minimum wasvalid in the case of carbohydrates, and even in the case offats, no less than in the case of proteins, there was little incli-nation to admit the practical working of the same law asfar as the inorganic constituents of food were concerned.The amount of the total ash, the amount of sodium chloride,and subsequently too the amounts of calcium and of phosphates,were considered—these were the only inorganic constituentsto which any attention was paid. I t was at most concededon the theoretical plane that the so-called ash contains anumber of other substances which must be included amongthe genuine nutritive elements. The practical inference fromthis admission, that the law of the minimum must be validin the case of every one of these additional substances, wassometimes disputed but more frequently ignored.

The most grievous defect of the old theory of nutritionwas the way in which that theory overlooked the universalvalidity of the law of the minimum. Investigators ignoredthe extent to which every tissue builder is dependent uponall the others, They failed to realise that what is decisivefor development is, not so much the absolute quantity ofthe various nutritive elements, as their relative proportionsThey did not understand that the bodily need in respect oany one constituent of a diet can be determined only wheiwe simultaneously take into account all the other factors o,nutrition.

An additional defect, one to which I called attentionfifteen years ago, was that in experiments concerning nutritionthe duration of the experiment had invariably been far tooshort. My o\to experiments lasted at first for a week. Subse-quently I extended them to a fortnight, and ultimately toseveAl months. I t thus became evident to me how intimate

INTRODUCTORY 19

is the connexion between the individual constituents of ourdiet. I learned that it is impossible to ascertain the body'sneed for any one substance, or to learn the way in which tha tsubstance acts upon the body, unless all the other constituentsof the diet are being supplied in optimal quantities.

The third defect in the earlier study of nutrition was,finally, the primary assumption tha t the ordinary diet ofcivilised peoples contains all the necessary constituents inthe necessary quantities. This assumption was supposedto be confirmed when in the course of a brief experimentno immediate or considerable loss of weight could be detected.I t became the practice, therefore, to adopt as the basis ofexperiments upon the requisites for nutrition the very thingwhich had to be proved; the average supply of the variousconstituents of a customary diet was assumed to representthe bodily need for these constituents.*

The present work was begun in 1920, when we were entitledto celebrate the decennary of a new epoch in the doctrine ofnutrition. In 1910 the liveliest antagonism would have beenaroused by the assertion that our diet contained, in additionto the familiar four classes of food constituents, quite a numberof other substances of a still uctknown nature, substancesabsolutely essential to the welfare of the organism. WhenSchaumann here in Germany first began to speak of suchessential accessory food factors, I was for a long time adverseto the assumption, and I attempted to explain the phenomenaattributed to tine alleged accessary food factors as the effectsof the inorganic constituents of our diet, these being my ownparticular hobby. I t seemed incredible tha t accessory foodfactors could have been overlooked for three quarters of acentury. Beyond question we were only at the beginningof our knowledge of the effects of the inorganic constituentsof food, and many surprises must still await us in this field

• This is the method which Rubner has employed quite recently whenendeavouring to ascertain whether the wartime and post-war diets of Germanycontained a sufficiency of calcium. He simply assumes that the pre-wardiet both of Germany and of Japan was adequate in this respect, and thushis comparisons enable him to draw the conclusion that our present dietcontains enough calcium. Unfortunately, not only does he use for his calcula-tions estimates of calcium content which are sometimes erroneous and some-times mere assumptions, but he likewise overlooks the fact that sjjecialistshave tepeatediy proved tliat the pre-war diet was deficient in calcium J

2 0 VITAMINS

of research. Even at that date, however. tl*« i '•*•«• «:*'numerous indications, merely awaiting amf\tttu%u* t\. *. <^foregoing explanation was inadequate, hit^i mi .».'. <•was the evidence that the substances in questi*<« **< *• Jf<

in almost infinitesimal quantities, like* those of ** J*r !^] I $

medicine; secondly there was the fart that tK- * ^ ; -were theraiolabile, were easily destroyed by !i* «** \\« *;indeed, that the application of modeiati- In at * « •-could exercise an influence upon the inoiRan*' M r J | f 'of a diet. For instance, we knew that whm ttn% i J 'for too long a time the complex carboph^pii-**' • * ' "and magnesium undergo decompo^ition, ami tha? A J r« *} "of insoluble carbonates and phosphates is 4**}^ H* I %the wall of the containing vessel. Thesi* tliii»4**l»''i!* .»are essential to the body of the new born infant , !}«*;i ^drawal from the milk leads to a defirienry f*f hint- JII t}^ f *and this may endanger the life of the nuNim: t'*i< st •withdrawals of inorganic substances irmn thr f* *i -**r

have a decisive influence upon nutrition, the rjn-mMK' hbe measurable in centigrammes or even in ihrifMui* n,whereas the antineuritic constituents ui t\n* U*+\ j inotable effects in quantities of milligramnii s *>t U+*iu i.*.a milligramme.

When yet other classes of food ronstitumf *> h,%*\ )«*discovered, having an analogous but nevfrthel*^* ••j-rofv »different influence upon nutrition, my hypc*ih«^s*' !^<^iuntenable. I was forced to admit that nttr diet tnn^t «- r^,small but very important quantities of many btfttrf f u ti?4n^kinds of substance. The chief reason why thrv ^'t*- tdiscovered sooner is one that has b«!**n already mU* .%u*lthe unduly brief duration of experimentH tiprm nytiifi^r

During the last few years, the Hteratitre i-rnlmlvsresults of these researches has attainfd ccmsir)er.ih)r' jtions. The world war, and the consequent s e v n , u Anations, have however greatly hindered the grcmth ofledge. It has been impossible for the individual tto keep himself adequately informed concerningsimilar to those upon which he himself was engaged, f %jinin Germany have we suffered from this hick, and ttut n cta in l / one of the reasons why the Germans have hem

INTRODUCTORY 21

greatly outstripped in the field of s tudy we are now considering—although Germany may be regarded as the scientific father-land of vitamin research. Hence the German publicationsduring the war had in most cases been long forestalled by theAmerican, to say nothing of the fact tha t the writings ofthe German investigators lacked the fertilising influenceresulting from the study of foreign models. Furthermorethe literature of the subject is very widely dispersed, so tha tyears of work are requisite to secure a competent knowledgeof what has been achieved.

Since from the very outset I took a keen interest in theseresearches, I have been able to secure a fairly complete collec-tion of the relevant literature. For this reason, at the closeof the first decennium of the investigation, I feel entitledto at tempt a comprehensive survey of all tha t has hithertobeen learned concerning vitamins. I t must be admittedtha t the task is almost beyond the powers of any one person,seeing that at least a cursory knowledge is essential in themost diverse fields of chemistry, physiology, internal medicine,pathology, and morbid anatomy. In view, further, of theconfusion that prevails upon this subject, i t should hardlybe necessary for the author to plead for the reader's indul-gence. Such a first attempt will hardly be free from a fewmistakes.

The confusion to which I refer is extremely conspicuousin the matter of nomenclature. At the outset of theseresearches, when investigators were still almost exclusivelyconcerned with beriberi and the kindred experimental poly-neuritis, there was a certain justification for considering boththe curative and the preventive effects of the newly discoveredsubstances on parallel lines with the familiar medicaments.Consequently, each newly discovered substance (or rather,mixture #of substances) received a special name. The firstof such names was " X acid," used b y Hulshoff-Pol in hispapers of 1902 38 and 1907 68 for the antineuritic principleisolated from the bean katjang-idjo (Phaseolus radiatus).The earliest Japanese investigators who attempted to isolatethe antineuritic substance likewise regarded i t as an acid,and named it " aberi acid." li6 Funk, however, found t h a the was dealing with an organic base, and spoke of* it as

22 VITAMINS

" vitamin." As a matter of course, numerous attemptswere promptly made to turn the new discoveries to practicalaccount. A flood of- antineuritic preparations invaded themarket, and the tide is still rising. I t was equally a matterof course that each of these preparations should receive itsown patented designation. Thus we have : oryzanin 2 l 0 ;torulin 220; orypan 884 ; antiberiberin 320; oridin I13C3; sita-coid 7J4; etc. Meanwhile, additional vitally essential nutritiveelements were being brought to light, substances requisiteto adequate nutrition. Rohmann 473,52i therefore proposedto give them the comprehensive name of " accessory foodfactors " (Erganzungskorper). The practical-minded Ameri-cans evaded the difficulties of nomenclature by refrainingfrom the coinage of specific names; they were content tospeak of " the fat-soluble factor A," of " water-soluble B , "or " water-soluble C." Abderhalden 8o3,1*30 used the term" eutonin " to denote the antineuritic substances as a class,this implying the possession of a knowledge of their mode ofaction—a knowledge which is unfortunately still lacking.Equally unfortunate was this investigator's choice of thename " nutramin " for the water-soluble growth-complettin,seeing that this substance contains no nitrogen. Variousother names have been suggested, with a varying measureof success. I may instance the ambitious " biophor" *3«among the less successful efforts, inasmuch as every suitableconstituent of our diet may be termed a " life-sustainer."Drummond,Il67 hoping to bring order out of chaos, has actuallymade confusion worse confounded by the proposal to usethe oldest name " vitamin " for the accessory food factorsas a class, to retain the term " vitamine " (this being theway in which the word has hitherto been spelt in England,although the Americans wri te-" vitamin ") for Funk's anti-neuritic substance, and to drop the qualifying adjective" water-soluble " or " fat-soluble " in the case of tlie othersubstances.

There are several objections to this proposal. An objectionto the use of vitamin as a collective name is that some of thesubstances under consideration contain no nitrogen, andtherefore axe certainly not amins. Further, it seems fairlycertaifi that there is a second antineuritic substance, free from

INTRODUCTORY 23

nitrogen, and distinct from Funk's vitamin, though like tha tbody it is readily soluble in water. But by the rules of prioritythe original* name belongs to the substance which was giventhat name by its discoverer; and there can be no doubt t ha tthe use of the term vitamins, to denote a whole class of sub-stances of this kind has, in actual practice, given rise to graveconfusion. If, however, the antineuritic substances are tobe known as vitamins, a still worse confusion will arise shouldthe same term now be collectively applied to various otherconstituents of our diet. There is good ground for the conten-tion that the misunderstandings still prevalent in the scienceof nutrition are mainly due to the improper use of the wordvitSmin. In physiological chemistry no less than in everyother science it is essential that names should be perfectlyfree from ambiguity, that there should be no possible doubtas to their denotation. In view of these considerations,preference must be given to the collective name " accessoryfood factors/ ' introduced by Rohmann, for this name impliesno more than that the substances in question are essentialcomplements of an adequate diet, tha t they are accessoryto the four classes of foodstuffs with which we have longbeen familiar—proteins, fats, carbohydrates, and inorganicsalts. But if this term is to secure acceptance in internationalscience, it must be translated into the international languageof science. In the present study, therefore, the author willuse the designation " complettin.'1 The term " v i t a m i n "will thus be reserved (in conformity with Funk's originalintention) for the nitrogen-containing antineuritic substances.Should any non-nitrogenous antineuritic substances be provedto exist, these must receive a distinct name. The water-soluble growth-promoting substance will be spoken of as" complettin B , " bearing always in mind tha t it has veryrarely been studied apart from the vitamins ; the fat-solubleaccessor^ food factor will be termed " complettin A " ; and theantiscorbutic factor will be spoken of as " complettin C." Thisnomenclature will secure complete freedom from ambiguity.

The diseases that arise from a deficiency of the accessoryfood factors must be similarly dealt with in the mat te r ofnomenclature. Funk 3*3 proposed to speak of these as" avitaminosis," but if the use of the name vitantin be

24 VITAMINS

restricted to the nitrogen-containing antineuritic principle,it would be extremely misleading to speak of scurvy (scor-butus), pellagra, and similar disorders, as avitaminosis. Forall these disorders due to a deficiency of one or more accessoryfood factors I shall, therefore, henceforward use the name" acomplettinoses "—the German vernacular equivalent "being" Mangelkrankheiten," the French " maladies de carence,"and the English "deficiency diseases." There is all themore reason for the use of such a collective designation,inasmuch as it is somewhat exceptional to find one of thesemorbid processes in a pure form. In most cases of deficiencydisease there is more than one class of substances lacking,although the overwhelming lack of one or other of them gfvesthe illness i ts specific stamp.

As already mentioned, the literature of the accessory foodfactors has now become so extensive that the individualinvestigator finds it barely possible to read without delayand to turn to practical account in his own work the publica-tions that are poured forth almost daily from the press.Moreover, anyone who stands a little aside from the maincurrent of research will often find it extremely difficult todecide to what extent an ostensibly new contribution reallycontains novel elements. In experiments concerning nutritionevery detail is of importance. The most trifling change mayrevolutionise all the conditions of an experiment. In manyinstances authors fail to recognise, or do not recognise readilyenough, the real source of the new or divergent results theyreport. This is only too natural . In earlier researches uponmetabolism, students were content to consider the effects ofproteins, fats, and carbohydrates ; and when exceptionallyscrupulous they would also take into account the result of asummary addition of salts. To-day we have further to makeallowance for four or five accessory food factors; and inaddition, in the modern and protracted experiments uponnutrition, we have to reckon with factors which in formerdays were completely ignored. The variety of proteinemployed, and its richness in tissue-building constituent,must be allowed for, although our knowledge of the composi-tion of protein is still far from precise. There is not evenone of the best-known proteins of which we can say that we

INTRODUCTORY 25

know all the factors requisite for its existence in perfection.Similarly as regards the fats, for we still do not know whichof these substances are absolutely indispensable to the organ-ism. Even more complicated is the problem of the inorganicconstituents of nutrition, so manifold in their variety. Fromseven to ten metals at least and as many metalloids haveto be taken into account. Each of these may exist in theanimal body, either in ionisable (i.e. salt-like) forms, or elseas a masked constituent of some extremely complex organiccombination which is perhaps itself essential to life. Fornormal growth, for normal wellbeing, it is not enough tofurnish by rule of thumb a diet containing certain quantitiesof %11 these substances. Liebig's law of the minimum appliesto each individual substance, and in part to each type ofsubstances. But the mutual relationships of the substancesare so intricate tha t it seems almost hopeless to undertakeresearches concerning the individual minima.

The further back we go in the history of the accessoryfood factors, the simpler do we find the experiments to havebeen, but for the same reason the earlier technique was compara-tively defective and the results were consequently morequestionable. To-day such experiments, if they are to berightly planned and if their results are to be correctly inter-preted, demand the most careful and extensive preliminaryconsideration. Furthermore it is essential, in these protractedinvestigations, to make due allowance for what has beentermed " the laboratory factor/ ' whose importance has beenquite recently recognised. We have to remember that theanimals we are subjecting to experiment are living in confine-ment, and are therefore far more infirm and far more exposedto noxious influences than their congeners living in a stateof nature. Especial consideration must be paid to the"cage-factor/ ' to the physical conditions under which theanimal!1 are placed, not forgetting the circumstance tha t amonotonous and uniform diet is being enforced upon them.Purely psychical factors likewise affect the wellbeing ofanimals. For instance, in some animals, the mere takingout of the cage once or twice a week for weighing will makeit impossible for them to thrive, even though their diet isall that can be desired.

26 VITAMINS

If, therefore, we wish to appraise the upshot of individualexperiments, we must bear in mind that the earlier investiga-tions are often vitiated ~by errors which invalidate the entireresult. I t must also be remembered that not a few experi-menters exhibit a certain mulishness, so that for one reasonor another they will not modify a wonted method ofconducting their researches, refusing to recognise or failingt o understand the improvements made by a rival. To sumup, we rarely encounter perfectly unambiguous results. Inmany cases an acceptable result can only be secured afterdue allowance has been made for the defective conditions ofthe experiment, or after errors have been eliminated bycomparison with the work of other investigators. I n Uiistask, the critic must not be frightened by any name, howeverillustrious. Why should he be frightened ? The wholescience is still in i ts initial stages, and only by making mistakescan we learn how to avoid them. Far be it from me t o maintaintha t my own technique as critic is wholly free from objection,bu t only by strenuous though benevolent criticism can wehope to achieve something as near perfection as human beingscan at tain.

Fo r several decades, Germany was the citadel of nutritiveresearch. The most noted names in this domain, those ofLiebig, Pettenkofer, Voit, and Rubner, are German. Butprecisely because their leadership had been so outstanding",the German science of nutrition became gradually enmeshedin rigid dogmas, which were ultimately regarded as indisput-able. I t has probably been for this reason that of late, in sobrief a time, Germany has been hopelessly outstripped in thescience of dietetics. The Germans are still dumbfounded a tthe revelation that there are nutritive substances t h a t cannotbe included in the familiar four classes, and that consequentlyall tha t has hitherto been learned concerning nutrition canhave no more than conditional validity. We have in Germanysofclong been accustomed to regard protein as a uniform entityfrom the nutritive outlook, that we now find it extremelydifficult to recognise in practice what has long been admittedas a mat ter of theory, namely tha t there are diverse sorts ofprotein and that their diversity of values must be recognisedfrom tke biological as well as from the chemical standpoint.

INTRODUCTORY 27

First of all, therefore, it will be necessary to study the latestviews concerning the biological importance of the variousproteins, tha t we may realise how fundamental this matteris in relation to the planning and the interpretation ofexperiments upon accessory food factors.

I have already emphasised m y opinion that—owing tothe fact that the importance of protein as a tissue builder,and the essential need for supplying energy for the maintenanceof life, are so easily understood—there has been a widespreadtendency to overlook and to ignore the importance of theinorganic salts, although this fourth great class of nutritiveconstituents has long been known to us. Let me insist oncemore tha t for these substances, too, the law qf the minimumis fully valid. The results of earlier researches supply ampleevidence of the physiological importance of the variousinorganic ions. In the history of the evolution of our know-ledge of accessory food factors, the value of the inorganicconstituents of our diet repeatedly forces itself on the attention.We- learn likewise that their interrelationships are vital tothe effective influence, not only of the accessory food factors,but also of the three primary classes of organic nutritiveconstituents whose place in metabolism had been assumedto have been perfectly understood. These problems mustalso receive close attention, if we are to be enabled rightlyto appraise individual expepments concerning accessoryfood factors.

What is true of philosophy and of history is equally trueof the science of nutrition. The further we advance in ourstudies, the more vividly are we made aware of the way inwhich one happening is dependent on another. In the endwe recognise as a fundamental principle t h a t the significanceof any occurrence can never be properly estimated in isolation.In suchjan estimate, all the cooperating factors must be takeninto the reckoning before a final judgment is formed. Inthe science we are now studying, this principle applies to theproblem of the bodily requirements of each'individual nutrit iveconstituent.

During the study of this book, the reader will perhapsfind the innumerable references to authorities disturbing,and may be inclined to regard them as superfluous. Cet him

28 VITAMINS

remember that " the* lahourei i w " i t h *J i<s hn« « f

that it would IK* unju4 ta n i iuf i 'n < n » mi < i T ^ < * r

others unnamed. Moieover, f }ta\<- a j>2 *4i 5 i< * « ! ?being precise in this m a t t u of tif.iti n ViL*% *the processes of nutiition 1 h.ivr u**t »J | r ^:» ? »j*, ] * * * L J* r f

with ignorance of thru* in«»h«.tl .uO j S\ 3 , "Now tha t my ideas have l»«n *u rt{4«h * i w *confirmed by iiKKlern <ii« t« tu u ^n^}^ . \t * * > * tt iI should sjnrify whirl* HMIIIN ai* tu\ * KU . : ' I v , i . «. .»<•those of other investig.ttfas. Kalsni; il ? i]< ]:< < M * < Umight simply be shelved as " ?)i« fan! •« < i a, 1 ' */ 4Lahmann." My book wntiM th in ful i^ ,i !«»•%« 4n t* ^mpurpose, which is to stimulate, th« '»ujMft i% *\ 4 *\hrscience of nutrition.*

of Dr. Lahmann's '.iii.ttrYtmo » j^mj r jr »«J *? r * - ? * „ * < ! »*in my book, bar Uuu\ it, J«*i tl#*f «»?/<• **v .- r r ir r ,*r * *<Lahxnanxi'.s UMthinf: n IUHV *#J*,4}rf«, »nl * i ^ r * t * «s .f? ras regards the ifi(*i >iiur fn?Ui?r*r s if *,i *• * I «<•*«- r* *• «

more accanlaut with thr }itit «f t *r »,* r «r Jt - f ** ^ *.»**.# * #It follows that I am «iUmr x* j ,.*jh«* i s J^» # r4S

CHAPTER TWO

T H E BIOLOGICAL VALUE OF T H E VARIOUSPROTEINS

i . T H E BIOLOGICAL VALUE OF THE AMINO-ACIDS

T H E reader must first be reminded that , according to thepioneer investigations of Emil Fischer and his pupils, theproteins are largely or mainly constituted out of ester-likeamino-acids compounded to form polypeptids. I t is remark-able to find how little variation there is in the compositionof the most diverse sorts of protein. As yet only a smallnumber of amino-acids have been isolated from the naturalproteins. Here is the list of these, the conventional namebeing given in the left-hand column, and the structural namein the right-hand:

glycocollalaninserinvalinleucinisoleucinasparaginic acidasparaginglutainic acidglutaminargininornithinlysincystincystein/J-phenyl-alanin

amino-acetic acida-amino-propionic acidjS-oxy-a-amino-propionic aciddimethyl-a-amino-propionic aciddimethyl-a-amino-butyric acidmethyl-ethyl-a-amino-propionic acida-amino-succinic acidthe anhydride of the samea-amino-glutaric acidthe anhydride of the sameS-guanidin-a-amino-valerianic acida, S-diamino-valerianic acida, c-diamino-capronic acida-amino-/3-propionic acid disulphidea-amino-/?-propionic acid sulphhydrate0-phenyl-a-amino-propionic acid *

29

3 0 VITAMINS

tyrosin oxy-phenyl-alanintryptophan jS-indol-a-amino-propionic acidhistidin ^imid-azolyl-a-amino-propionic acidprolin a-pyrrolidin carbonateoxy-prolin oxy-a-pyrrolidin carbonate

Leaving* out of consideration the anhydr ides and cys t r i n(which are in all likelihood no more t han decomposi t ionproducts formed in the course of the experiments) , we a r ethus concerned with only eighteen arnino-acids, ou t of whichthe innumerable proteins are constructed. Of course cvrflthis limited number of constituents gives amp le scope forvarieties in combination. Out of the eighteen axmno-a£iUsjno less than 6,708,373,705,728,000 proteins could theoret ical lybe built up. Were we to take no more t h a n ten of the amino*acids, with these we could form 595,071 variet ies of p ro te in .But the differences between the proteins do no t depend solelyupon differences in the arrangement of these par t icu la r con-stituents, for unquestionably most proteins likewise conta invarious quantities of other substances besides the ammo-acids,Finally we have to reckon with s tructural differences, whichmust certainly arise during the formation of optical ly ac t iveamino- acids.

I t has long been Imown tha t the digestion of p ro te insinvolves their decomposition, and tha t when the influence oftrypsin is sufficiently effective this spli t t ing-up m a y proceedas far as the formation of various amino-acids. Conversely,

'Abderhalden has been able to prove 45* t h a t dogs can bequite as efficiently nourished upon completely dis integratedprotein as upon protein in the natural s ta te . I t was , indeed,subsequently shown that during the process of normal diges-tion the disintegration of protein does not usual ly go so faras the formation of free arnino-acids, being ar res ted in t hepolypeptid stage. Still, Abderhalden's experimerfts h a v edemonstrated as a matter of principle t h a t t h e an imalorganism is at any rate competent to build u p i t s own specificproteins out of the requisite amino-acids. Qui te a n u m b e rof investigators had anticipated Abderhalden in th i s demon-stration (though somewhat less drastically), inasmuch as inexperiments upon animals they had shown tha t when a var ie ty

BIOLOGICAL VALUE OF VARIOUS PROTEINS 31

of protein lacking in some constituent indispensable to normalgrowth is given as a food, this protein may be renderedbiologically adequate by adding the desired constituent tothe diet.

In the before-mentioned work, Abderhalden likewise provedthat certain tissue-building constituents of protein are abso-lutely indispensable to the body. Above all, this is true ofUtryptophan, which cannot be substituted by any other pro-ducts of protein disintegration. It is true also of ktyrosin,which can be replaced by its antecedent 1-phenyl-alanin,but not by any of the aliphatic amino-acids nor yet by thecorresponding keto-acids. Thereby Abderhalden confirmedwhSt Osborne, Mendel, and Ferry 2*5 had previously main-tained, that the animal organism is incompetent to effect " ring-closing " (cyclopoiesis).

Glycocoll, which can easily be produced by the oxidationof alanin or even of serin, need not apparently be providedready-made in the food. Prolin, again, which is readilyproducible in the body by the oxidation of histidin, need notbe supplied if the last-named antecedent material be furnishedin the diet in sufficient quantity. Finally, it was provedlater that Ircystin is essential. But in my opinion it stillremains to be ascertained whether this substance cannot besubstituted by the corresponding sulphhydrate cystein,since the latter can unquestionably be oxidised to formcystin within the body.

Abderhalden was unable to show that d-lysin, arginin,ornithin, l-histidin, and d-glutamic acid, are indispensable.

In this chapter I have given the premier place to Abder-halden's researches because his name enjoys exceptionalrepute in Germany. But he was far from being the first toundertake experiments of the kind. In the United States,experiments in the artificial feeding of animals were longago inslituted, Osborne and Mendel, in particular, havemade extraordinarily comprehensive and far-reaching researchesin this field—researches which are directly related to Metschni-koff's views concerning " ntitritive pills " ; but the enquiryas to the validity of the theory was undertaken long beforeit had become widely known. Osborne and Mendel havebeen greatly interested in the question whether animfils can

32 VITAMINS

carry on their vital economy with the aid of comparativelysimple means; whether, for instance, phosphorus in purelyinorganic combination will suffice. In these experiments,as soon as their duration was extended over many days orseveral weeks, the varying biological importance of thedifferent proteins began to become manifest. As early as1912, Osborne and Mendel were able to prove that the diet*must contain certain minimal quantities both of tyrosin and]of tYyj)ioj)h(in?%5

In the work just mentioned, and again later,349 these investi4gators showed also tha t glycocoU is not an essential factor inld ie t ; Lewis, 653 and Lewis, Cox, and Simpson,Il83 came tothe same conclusion. Contradictory, at first sight, is* thestatement of Nitzescu,8°4 that the protein of maize is incompe-tent to promote proper growth, owing to its lack of tryptophanand its inadequate content of glycocoll and lysin; but theRumanian forgot to make a control experiment, adding theaforesaid substances to the diet in order to ascertain if anyor all of them were truly indispensable. I have already adducedtheoretical grounds for the opinion that glycocoll is not essen-tial, inasmuch as this substance has such a composition thatit must be formed in the organism by simple oxidation outof all the other aliphatic a-amino-acids. Such, too, is thebearing of Ivar Bang's discovery,5<>8 tha t proteins poor inglycocoll, and perhaps also in alanin, have in the rabbit noeffect upon the amino-acid content of the blood; these sub-stances, when present in very small quantities, are promptlyused for building up the protein of the animal body. When,on the other hand, foodstuffs rich in glycQcoll were given,an increase in the amino-nitrogenous content of the bloodensued; obviously because, when the bodies rich in glycocollor alanin were worked up within the animal organism, amino-nitrogenous substances were produced in excess of the needsof the tissues. I t is well known that when an "aliphaticcarbon chain undergoes oxidation in the animal body, theoxygen seizes the terminal carbon atom—or, if this be alreadya carbonyl, the adjacent a-carbon atom. But an exceptionto the rule occurs when the a-carbon atom is linked to anamin group, as is the case in all the naturally extant aliphaticamind-acids. Then this atom is overpassed, the oxidation

BIOLOGICAL VALUE OF VARIOUS PROTEINS 33

affects the jS-atom, and the chain is broken with the formationof N H 3 . CH2 . COOH—glycocoll, to wit. There is, however,little likelihood that alanin can be formed in the body, seeingthat in alanin the j8-atom is not oxidised. Throughout theliterature of the subject, in fact, we can find no indicationthat it is possible to dispense with alanin. Sure, indeed,tells us la63 that the addition of alanin to a protein of verylow nutritive value did not bring about any improvement.But in this experiment there were so many other unfavourablefactors that the ineffectiveness of the addition of alanin doesnot justify any inference concerning the indispensability ofth%t substance.

Just as, during the process of oxidation within the animalbody, glycocoll must arise out of the aliphatic amino-acids,so, and for the same reason, must prolin arise out of histidincompounds as a terminal product of biological oxidation.In actual fact it appears that this amino-acid is not a vitallyessential constituent of our diet,Iz63 provided that a sufficiencyof histidin be supplied.

Indispensable, on the other hand, are valin, leucin, andisoleucin. Leucin (amino-isocapronic acid) cannot be substi-tuted by norleucin (normal amino-capronic acid).1200

As far as the so-called hexone bases are concerned,peculiar conditions appear to prevail, and the matter has notyet been cleared up. Numerous experiments seem to havdLshown beyond dispute that lysin is an essential dietetic factotf'and that the animal organism must be supplied with consider-able quantities of this substance. , (Cf. 349, 43*, 49a, 55°. 5***<598, 613, 634, 680, 804, 1095, IOOO \

It is different as regards arginin and histidin. When boththese bases afe lacking, normal development is impossible,and it is even impossible to maintain the body-weight.Nevertheless, although the two substances differ so greatlyin composition (arginin has an open carbon chain, fromwhich there is no prospect of passing to the heterocyclichistidin), Ackroyd and Hopkins 535 and Geiling 65° agree inreporting that adequate growth can be secured when eitherarginin or histidin is supplied in the absence of the other.The explanation perhaps is that the bodily requirements arevery small in the case of both substances—for it is hardly

34 VITAMINS

conceivable that vtthvr can hv tr,in%foim<*d mm Ihr uthn

Cysdn is of pmil ia i composition, and nuin»J*«ii «»h f i \ utions h a w shown it to hr indispmsihh* t«» nutitt:«»n i rhowever, the it*st*i vatitin inadi* on p. ,!?» hv*i* pi ' t t t inn< h in cvMin, Mich as caM-mMl< u " i and J.M talhunnn,1'**•M 'juiH* an enhanced uutsiti\<* valur whin null *j?na*fHi*u{ rvstxn a i r sinniltaninu-Jy acJmini^tiiMl,

Iiia^mtuh as th*1 annual ot^.iinMti M t-ms |*» b« in* ^nijd-trnto ar Jnrvr t \ c lupoirsis, it is ohvicnts that f*ht?:\! uiarAnbr an uifiisjf«*sisuhh* factor of n u t r i t i o n ^ Mitt in II tan oh,Hf'ivation to ihv o\>\n)s\\v viivt tt

fv* hut m flii* < %|tli** «irii3iim'4ratton of anuuo at ids a l t ' r ua t t d nu l l |M H«-K! . ofjirottin starvation (Itum;; ^ h i r h annno^a«i4* vvii«4 of!«ing fornirfl within \hv hody. In h tm^ ' r Matt^ tin »*• .iat ids a i r vigorously rt'tained, and tins niav havr ial ifi«tl the

Inrng snpphfd in thr fomhIt is rqually ohvioir, that tyr^wn IIMJ 4 hr ,m

fhiir t ir fat tor ; thr irrjmsiti* t]Uantitl< * of flu,an* Miiall^M but vitaHv inij»»itant.J ** Mit«h«ir^ I*tu ttit* ron t ia ty "5* m# as m th#* u n * oj j*li* it\) .da

tin* j«« nliar conditions <4 th r «*xp« unit nt,, the* iirtrv^iry amount is v«iy .mall v * "Ihis

for by AUiidrh;iidi*ii'sobst»iv»ttioii * n that tyiosmalanm) is to sotm^'Xtt-nt ii-{it«M«Mi»lr l»v iNant t - in ] y;iJ*iniwf whith und**i|4«#m oxidation within thr twnly* Jlic<ixi<lAtt<m of a bi*n/ol rini*. vi diffir tilt tu t*tirt t in thr Utniijitoryv

in a Ltiinhar ticcitnrrnrc* in thi" animal o i^ inkin , t nn^l onlymifind th«* r^adrr ni the tr«insjor!n;tfi«m of lu j

f h4vr rnon* than onn* insisted that ttypiaf»h*tnindiHju'iisaWi* dktHic factor. C)n tht*orHuaI ffroiimh iftu- NO# owing to the coftif4ratrd rtini}Hi>ititin of tiit* >itU»tAticr,and owing to th r imomfMlrnn; of tht* liniti^ii ^t^mntn t«i

carbon chains, 'I In* mfr rn i r r i% «aitlinnrd byolMrrvatiims, (Cf. I*?* *M- * . ^ ^ %H ^** |r*^ •»*!.)

to the bHfcire*ittrntt<>nt*d ttiMpsirity of th r b«dly# itthftt tryptciphiin cannot IK: trpiortt l for dietetic

by its difc4ntr^ratioti product cvntirie nrnl ^ f Sincethe organmn lucds fairly b i g c amciuntii of trypti#|#ii4ii# we

BIOLOGICAL VALUE OP VARIOUS PROTEINS 35

find that , when the proteins in the food contain only smallquanti t ies of that constituent, growth runs parallel, to a certainextent , with the tryptophan content.49*, 613 j ^ i s partly explainsthe superiority cf mother's milk to cow's milk for infantfeeding, seeing tha t the lactalburnin of human milk ispeculiarly rich in tryptophan. Although human milk con-tains a smaller percentage of protein than cow's milk, theabsolute tryptophan content of the former is considerablylarger. *w 11 is noteworthy tha t when there is a long-continueddeficiency of tryptophan in the diet, the endocrine glandsdegenerate just as they do when there is a complettin deficiency.Tins will bo further discussed in the sequel. Enough forthe moment to point out the superlative importance, inexperiments upon the effects of the complettins, of attendingt o the satisfactory composition of the dietetic proteins.ro55

Mo investigations concerning oxy-prolin have come underm y notice ; but we can hardly be mistaken in assuming that,l ike tyrosin, it is replaceable by its unoxidised antecedent.I n the case of oxy-prolixi this antecedent is prolin, and perhapsalso histidin. So complicated a substance, "being heterocyclic,can hardly be replaced by any other food constituent thanthose just named.

Before closing this brief survey of the biological importanceof the ammo-acids, we must refer yet again to Mitchell'swork,549 which shows that during brief experiments even graveerrors in diet can. be compensated. Experimenting on ^vhitemice, Mitchell gave them a diet consisting of a mixture contain-ing 34 % of starch, 28 % of protein-free mi l t (providing B,C, and inorganic salts), 10 % lard, 18 % "butter (providing A),6 to 7 % sugar, and 4 to 6 % of a mixture containingvarious ammo-acids; this alternated with the same mixtureexcept for the last-named ingredients, the arnino-acids beingreplaced by a supplementary 10 % of sugar. He found thatthis alternation of a protein-free diet with one in which theprotein content was manifestly inadequate gave better resultsthan either the protein-free diet or the diet containing amino-acids given uninterruptedly* Obviously the defects in thecomposition of the amino-acid mixture (which wheafgivenunintermittently could not "but lead to overfeeding with someof t h e amino-acids and to underfeeding with others) were miti-

36 VITAMINS

gated in this way, that in the intervals when a nitrogen-freediet was given the body was forced to draw upon its ownstores of material. We know that in such circumstancesthe most important constituents are vigorously retained bythe body, and tha t on the other hand an intensive nitrogenhunger is induced. By these two factors, during the periodswhen the ammo-acids were given to the; white mice a betterutilisation of the nitrogen was ensured than was possiblein the instances in which the axnino-arids were given iminter-mittently. Of course the organism's jwwers of srlf-help inthis respect are strictly limited, and Mitchell could not keepany of the white mice alive for more than 98 days. We set*,however, tha t in brief experiments the organism has numerouspossibilities of self-help, numerous ways of compensatingfor defects in diet. Brief experiments, therefore, do notafford valid conclusions concerning the effects of an experi-mental diet* If gross fallacies art* to be avoided, the experi-ments must be continued for so long a time that the sourer*of self-help in the organism run dry. lixperiments upon theutilisation of proteins have commonly infringed this rule •especially when domestic animals have been the M*bj#rts ofexperiment. Thus only can we explain how, in fjerntanyduring the. war, yeast (a substance of very low nutritive value 1as far as its protein is concerned) could \m recommended an »an adequate source of protein.

Inasmuch as the ammo-acids can only be utilised by theorganism in ^o far as the diet contains other roniti t t trnt*enabling these, acids to be amplified into protein* proper tothe animal under consideration, the supply (whetlii*r by mouthor hypodermically) of arnino-acid* that cannot be thu*complemented is a useless burdening of the body. Thin i%proved by the rise in the amino-tirid content of the bloodin such circumstances, and by the increased excretion ofammo-acids in the urine, s*** w

In view of all these considerations, a d ivovr ry made byAbderhaldrn <s» is easy to understand : it in almost indifferentwhether we give as food the protein specific to the animalconcerned, or protein from some extraneous source ; on theother hand, the aggregate protein of an animal H greatlysuperior to the protein derived from any individual organ,

BIOLOGICAL VALUE OF VARIOUS PROTEINS 37

2. T H E RELATIONSHIP OF THE PROTEID TO THE

NON-PROTEID NUTRITIVE SUBSTANCES.

Of course in all such experiments the investigator muststrictly observe the conditions that were found essential inthe very earliest studies of protein metabolism. There mustbe an adequate supply of energy, measured with a liberalrather than with a sparing h a n d ; and a suitable ratio mustbe preserved between the nitrogenous and the non-nitrogenousnutritive constituents. A vast amount of writing has beendevoted to this ratio, and the most contradictory views havebeen put forward. Especially conflicting are opinions con-ceAing the question whether nutrition can be adequatelysustained by proteins and carbohydrates in default of fats,or by proteins and fats in default of carbohydrates. Thisproblem is intimately connected with two others. First,can fats and carbohydrates be manufactured out of proteins ?Secondly, are fats and carbohydrates really built up into thesubstance of the organism, or do they merely serve to supplyit with energy ?

The latter question is the more important of the two,for if fats and carbohydrates do not form essential constituentsof the living tissues, their manufacture out of proteins ismanifestly superfluous. Proteins unassisted could then providefor the requisite supply of energy. For a long time, physiolo-gists were inclined to assume that fats and carbohydratesserved merely as fuel or reserve. The German experience ofwar nutrition has, however, pointed towards the conclusiontha t fats have a certain value as tissue builders supplementaryto their value as energy providers. I t might be contendedtha t the ailments attributable to a deficiency of fat in thediet were mainly due to a lack of fat-soluble A, and the infer-ence mi&ht seem warrantable as far as t he great majority ofthe population was concerned. But Similar ailments occurredin vegetarians, despite their daily consumption of such foodsas spinach and carrots, which contain large quantities offat-soluble A. We are therefore led to infer t h a t fats areindispensable as tissue builders.

The objector may still point out t h a t symptoms of fatdeficiency are not seen when there is a very liberal supply

38 VITAMINS

of protein. But, on the one hand, almost all food rich inprotein is also rich in fat (pulses, and even lean mea t ) ; and,on the other hand, it may now be regarded as proved thatfat can be formed out of superfluous protein. The ill-effects \of a fat-free diet can, therefore, only become apparent whenthe supply of protein is reduced to somewhere near theminimum. Unimpeachable experiments of such a characterare not yet forthcoming.

However, the experience of various investigators accordswith the data furnished by war dieting. Bierry957 was ledto the firm conviction that fats must actually serve as buildingmaterials in the animal organism, and that there must there-fore be an essential minimum of fat in the food no less thanan essential minimum of protein.833, 973, 06 A specialist inthis field, Maignon, emphasises his view that the reason whyit is so difficult to ascertain this minimum is that fats can be*manufactured out of proteins within the animal organism.744On the other hand, the same investigator has found that apurely protein diet is directly toxic to the animal organism. tThe tdJ^ic influence is not solely explicable as the outcome of *the effect of acids, for it cannot be prevented by the adminis-tration of alkalies; but it can be prevented by adding fator carbohydrate to the diet.778, 882, 883, 1081 Amar comes tothe same conclusion.779 Both Maignon and Amar opine thatin these circumstances the fats have a protein-saving influence.Maignon 87o, 9°3 attempts to explain this by suggesting thatthe missing amino-acids may by aminisation be formed outof the fatty acids. (An objection to this theory is, that theanimal organism is incompetent to build up amino-acids outof fatty acids by aminisation.) There must, however, becontributory factors, for the toxic influence of the proteinsexhibits marked periodicity; i t is most apparent in springand autumn, least apparent in winter and summer. Possiblythe more vigorous growth that occurs during spring an3. autumnhas a bearing upon this matter.941, xo8x, nz8 Carbohydrates,likewise, can counteract the toxic influence of proteins.Bierry, Maignon, and their pupils are all in agreement here.778>779* 833> 936,957, 963,973. i°39, *™6 The addition of lard to theextent of one-fifth of the weight of protein is already enoughto improve the utilisation of the protein; but the best result,

BIOLOGICAL VALUE OF VARIOUS PROTEINS 39

namely nutrition with the lowest quantum of protein andof energy supplied, is secured when e^ual weights of proteinand fat are given. 778> 883, 941, *™* Furthermore, a similarimprovement in the utilisation of proteins can be securedby supplementing them with carbohydrates; but in t h a tcase the supply of calories and the consumption of proteinwere higher with a diet containing equal weights of p r o -tein and starch than with one containing equal weights ofprotein and fat.77*. 941, "28

This view, that fats induce a better utilisation of proteinsthan carbohydrates do, is directly opposed to the opinions o fAtwater, Mendel, and Levi ; and it is contested by T e r -roine,^1 who, however, has no evidence to offer in rebut ta l .Maignon,87°, 903 in order to explain this mode of action, assumesthat there is increased formation of amino-acids out of both,the glycerine and the fatty acids of the fa t s ; the effect o fcarbohydrates is accounted for by their competence to s u p p l ythe demand for energy .93 Whereas it is difficult to bel ievethat ammo-acids can be newly formed out of either glycerineor fatty acids (see above), in my view the observed facts a r ereadily explicable. We may suppose that , when fat is lacking',proteins must be used up for the formation of fat. The reby ,first of all, there ensues a greater consumption of protein^;and, secondly, the consequent products of protein decomposi-tion may very well account for the toxic phenomena tha*tare witnessed in the bloodvessels and the kidneys ; w h i l psimultaneously (in accordance with Maignon's view) a coii^-siderable proportion of the protein must be expended t o ,supply the requisite energy. Carbohydrates, finally, t a k eeffect as savers of protein chiefly in virtue of their power t ofunction as readily utilisable sources of energy. Thus t h eprotein-saving effect of carbohydrates is direct, tha t of f a t sboth direct and indirect. These considerations l ikewiseexplain Qvhy it is that the best results as concerns both theutilisation of the protein in a diet and the calorie consumptionof a diet are secured when the diet contains fat and carbohydrateas well as protein, and when the weight of fat is at least equalto that of the protein, whatever proportion of carbohydrate thediet may contain.

I t is or should be obvious tha t valid and u n a m b i g u o u s

40 VITAMINS

results can only be expected from such experiments whenthe supply of food constituents is kept down to somewherenear the minimal requirements, above all as far as proteinis concerned. The defect of the researches of Atwater andhis collaborators is that they gave quantities of protein greatlyin excess of the minimal requirements, thereby obscuring theinfluence of the fat upon the calorie consumption and stillmore its influence upon the protein consumption—for fatcould be manufactured out of the surplus protein.

I t used to be believed that very large quantities of proteinwere requisite, and those who still cling to that view will besurprised to learn that a diet containing equal quantities offat and protein is the most economical. Amar, however,showed as long ago as 1909 that in man the best utilisationof the food is secured when the diet contained equal weightsof fat and protein. The protein requirement will then beminimal, and even the fat requirement will be only a fourthor a fifth of what was formerly assumed to be necessary.

3. T H E IMPORTANCE OF INORGANIC CONSTITUENTS

IN METABOLISM.

Before we proceed, attention must be drawn to anotherfact which in Germany has been strangely overlooked andhas to a great extent been even directly denied. I refer tothe effect of the inorganic constituents of the diet upon theutilisation of the protein it contains. The American specialistsrequired nearly a decade to learn from their experimentsthat not only the total quantity of inorganic constituents,but also the quantities of the individual inorganic constituentsand their mutual quantitative relationships, and in especialthe relationship between anions and cations, are of decisiveimportance in relation to the demand for protein. But, incontradistinction to their German colleagues, the Americansdid learn this in the end, and the consequences of the lessonare manifest in the incomparably better results secured bythe Americans, not only in respect of the utilisation of theprotein content of the experimental diets, but also in respectof the mean duration of life of the animals subjected toexperiment. I t is indeed strange that in the land where thelaw ofcthe minimum was discovered, this law should be denied

BIOLOGICAL VALUE OF VARIOUS PROTEINS 41

as far as the inorganic constituents of a diet are concerned.In 1912, barely two years after myself, Osborne and Mendel 22Sexpressly declared that a minimum of the various inorganicconstituents is essential to the maintenance of life ; a compara-tively small supplement of each then suffices to ensure normalgrowth. A further increase of these inorganic constituents,even an immoderate increase, exercises no further influenceon growth. In the next chapter this mat ter will be moreclosely considered, but it was necessary to refer to the questionhere because without some knowledge of i t the investigationsconcerning the biological value of the different proteins cannotbe properly appraised, and because these relationships throwlight* on much that would otherwise be obscure. I needmerely remind the reader how long the belief prevailed tha tmaize protein is poisonous, until at length the realisationcame that the toxic symptoms which had attracted attention \were merely a form of acidosis consequent on the lack ofcertain inorganic constituents.451/ etc«

4. T H E BIOLOGICAL VALUE OF THE VARIOUS VEGETABLE

PROTEINS.

The most important of vegetable foods are the cereals.They are diffused all over the earth, wherever plant-life ispossible. Many persons are of opinion tha t they constituteideal foods, and Hindhede declares tha t wholemeal breadcomprises an adequate diet without any supplement. Thisis by no means the case.

Rice demands consideration first, although comparativelyfew investigations have been undertaken concerning thebiological value of rice protein. Boyd Il87 found its worthto be four-fifths that of meat protein, but his experiments areopen to criticism because he was not aware of the importanceof the inorganic constituents of a diet, and because his experi-ments were of too brief a duration. On the whole it wouldseem that rice protein is of a rather low grade, for Buckner,Nollau, Wilkins, and Castle 877 report, in agreement withAbderhalden,8^ that rice as the exclusive source of protein^does not suffice for normal growth. In especial, the develop-ment of the genital organs is impaired, and reproduction ishindered. The insufficiency of the aggregate rice protein

42 VITAMINS

would seem to be quantitative rather than qualitative, Itcontains all the substances requisite for tissue building, hutsome'of them are not present in adequate* anmunK If tin*animal can be supplied with a suifinmcy of ri« r pirittm (byadding isolated protein to the rice miisunirrl), normal rl<-\r]op-mont and normal growth take plan*, P.uf, atmtdinK toOsborno and Mendel,?*6 for this result to be arhi«-v«'d flu;rice protein must comprise from i(> to tj fl

r> of flu* total hnn\,Seeing that polished rire contains only f» " t, nf piot»in, aitrjunhullud rice no more than 4.7 %, 1 in* a^ surh i * MM ninprtentto promote normal development or to maintain Wright,Boruttau77» declares that ground rice (i.i*. the rr»!o%p«nn)contains a higher percentage of ptotein th.m wholi* Tier,There must be some enor of <»bservaticm hcn% int the fxpi*n»ence conflicts with that (A all other investi&itrjfv Othrthere is general agrec»im*nt that in ihr tut* pjain thecontains the highest grade and the endosperm the fou t%i gradeprotein.

In like manner, Osbnrne and M<ndel i& tUvlnn* that inthe case of maize tin* embryo alone contains piotrin nt|«*rjiK4t«?for nutrition, whereas mother th«» \v\m\v gram imi thr Houris competent even to maintain weight in animals f«tl x%\umi t . Then! have been numerous resiMirht^ conrmnng ttwbiological valni* of m a k e protein, the subject having at t rar t rd*great attention because the inadequacy at tnxuity *rf n ia i^fha^ been n^arcled an the cause of pellagra mnltcrs In \HI{more fully considered in the chapter mi that r lwasi\ #\ll>rr*toni and Tullio ni and Sherman mt>1 agree in stating that inman a nitrogenoiis balannt rannul be mmiimnM with nia i / ras the only j&ource of protein in the <lit*t, Arrnrding toSherman, Wheeler, and Yates,**1 and arrnniinK to Shfmnanand WintcirH,?*^ maize protein is for human twinge rvt*n worsethan the* already inadc^rjtiate wheat protein, *I In* inadrtpiaryof maize protein for growing pig* hm l*een dr finifffy provedby Hart and McCoIlum.w II«igan/6 \ Mc('ollttm< Simmond*and Pitz#^7« and Hart, b t r rnhork, and L« t r h e r ^ * *«o; itdoes not even suffice to maintain wnight in thr uditlt pig3?*Baglioni#4^ Mogan/61 Md*olhtin txnd Samtnomk^t* andlAbderhalden V have pmvt*d that maize pmtrtn will notsufiico to maintain growth in rats . According to Abckrhaklen,,

BIOLOGICAL VALUE OF VARIOUS PROTEINS 43

the biological value of maize protein is no greater than thatof the endosperm protein found in polished rice. Hart ,Halpin, and Steenbock,655 and also Nitzescu,8°4 state thatmaize protein is inadequate even for grain-eating birds likethe barndoor fowl; sooner or later the animals becomeemaciated and perish. Boyd Il87 likewise considers the proteinof maize to be of a very poor quality, having only one-thirdor one-fourth of the biological value of meat protein. Maizegluten, isolated as a by-product during the preparation ofmaize starch, is also, according to Osborne and Mendel,55°of extremely low biological value, although much largerquantities of it than of crude maize can be administered asfoocfc Nevertheless, maize contains certain proteids (maizeglutenin or glutelin), which are fully adequate to promotegrowth in animals. But the utmost amount of these inthe grain is 30 %, whereas at least 50 % of maize consistsof the quite inadequate zein,2I7,349, 393, 423, 1075. ^ 1^3 so thatthe net result of maize feeding is unsatisfactory. Of course bygiving a sufficiency of the aggregate maize protein, a tolerableresult could ultimately be secured, but this would be a veryirrational way of feeding, seeing that two-thirds of the proteinare more or less completely lacking in essential tissue-buildingconstituents. Zein is especially characterised by the almostentire absence of lysin and tryptophan.55°> 6l3> 634 Conse-quently it is possible to supplement maize protein effectivelyby adding to the diet blood, egg albumin, edestin, cottonseedprotein, casein, and, above all, lactalbumin—the two lastbeing peculiarly rich in lysin and tryptophan. Superheatingmaize protein in the autoclave does not better i t ; on theother hand, in the case of maize as in that of cereals in general,the process of germination appears to enhance the value ofthe protein. Attention may here be again drawn to thefact that the maize grain, like all other seeds, is inadequatein respe<!t both of the total quantity and the composition ofits inorganic const i tuents^ , 451* 568> 578> 6l*, 655> 9°°, "43 In thecase of the higher animals, the lack of calcium has a verymarked effect on growth. 34* Unmistakable, too, is a gravedisproportion in the relative quantities of acids and bases,and Baglioni45* expressly states that the animals he wasexperimenting on (guineapigs) died of acidosis. The •same

44 VITAMINS

observer draws attention to a fact which seems to be connectedwith the foregoing, and one which I myself demonstratedten years ago ; when an animal is fed upon an inadequateprotein, a retention of nitrogen may occur despite the declinein body-weight. If the maize diet be supplemented by asufficiency of fat, etc., then (in the absence of growth) anincrease in weight may occur through the deposit of fat andthe retention of water in the tissues, but the retention ofnitrogen is apparent merely. With the substitution of anadequate protein and the addition of a sufficiency of alkali(or even with the latter alone), there ensues a discharge ofthe accumulated nitrogenous and acid residues, with a resultantabrupt fall in weight. As long ago as 1909, I referred to thisretention of nitrogenous residues as being the outcome of theretention of acid residues which must occur when there is adeficiency of alkalies in the food.

As regards wheat protein, McCollum and Davis 425 declarethat 6 % in the food suffices to ensure normal growth in youngrats ; bu t these results are in sharp conflict with those of allother observers, such as Abderhalden *96 and Osborne andMendel.873,1082 When working in conjunction with othercollaborators (Hart,409 and Simmonds and Pitz 579,598), McCollumis constrained to admit that wheat protein does not sufficeto maintain growth in rats ; and Johns and Finks,Il89 experi-menting under very rigid conditions, come to the same conclu-sion. Hart and McCollum,4<>9 and Hart, Halpin, and Steen-bock,655 found that wheat gluten, the residue from themanufacture of wheat starch, was inadequate for growth, inr a t s ; Drummond 876 came to the same result with chickens.Har t and McCollum 409 found wheat inadequate to promotegrowth in pigs, and McCollum and Simmonds^ 1 found i tinadequate to promote growth in dogs. Sherman, Wheeler,and Yates 720 found that wheaten bread made of a 74 % flour *was insufficient to maintain body-weight in human beings,and their results were fully confirmed by the investigationsof Sherman and Winters.74* According to Sherman, Wheeler,and Yates, and also according to McCollum and his collab-orators, wheat protein has unquestionably a somewhat higher

• A flour resulting from a milling process in which 100 lbs. of wheatyielded 74 lbs. of flour.

BIOLOGICAL VALUE OF VARIOUS PROTEINS 45

biological value than maize protein, but they seem to supple-ment one another to some extent. A mixture of the twois still inadequate, but it gives better results than an exclusivediet of maize or wheat.

When we consider the separate proteins of wheat, wefind that the relationships are much the same as with maize.According to an early (and therefore somewhat untrustworthy)investigation by Osborne and Mendel,2I7 glutenin, one of thetwo chief constituents of wheat gluten, is adequate for growth,whereas gliadin, the other chief constituent, is quite inade-quate. To convert the latter into an adequate protein, lysinmust be added.1200 But although gliadin is not competentto promote growth sufficiently,I27» 393.1075 it is apparentlycompetent to maintain weight.^5. 24*. 4*3 It seems question-able, however, whether gliadin can really maintain the body'sstores of protein. According to Baglioni,393 it can bring aboutthe maintenance of the nitrogen content of the body, andcan even increase this; but just as in feeding with maizeprotein, so here, the increase in nitrogen content is a spuriousone dependent upon the storage of residues, and is attendedby an inevitable loss of weight. Since the inadequacy ismainly referable to a lack of lysin, and perhaps to some degreealso to a partial lack of tryptophan, wheat protein can beefficiently supplemented by substances rich in these amino-acids,such as gelatin, meat, eggs, milk, or considerable amounts ofcasein, or even by the protein of the earth-nut (Arachishypogsea). The lowest-grade protein of wheat is that in theendosperm. The protein of the bran is of much higher value,even superior to that of the germ as far as concerns richnessin substances essential to the maintenance of the animalorganism ; on the other hand, for the purposes of growth thegerm is somewhat superior to the aggregate grain, and twiceas good a£ the endosperm protein.77*, 873, *°83 According toBoyd,Il87 the biological value of the endosperm protein isonly about 39.5 % of that of meat protein.

Abderhalden found in his experiments *96 that the aggre-gate rye protein was inadequate for the maintenance of growth;it was inferior to barley protein, but certainly superior towheat protein. Osborne and MendelIo8a also state that#ryeprotein is unsuited for the maintenance of growth in rats,

46 VITAMINS

but according to these authors it gives better results thanbarley. We must leave the question undecided whether thedivergency between these two authorities is to be* explainedby the varying conditions of the respective experiments(the Americans certainly had a better mixture of salts an aconstituent of their trial diet), or by accidental different^in the specimens of grain used. As early as i'ji.5, I wa*myself able to show beyond dispute w. *»i. ;H«. *M that inhuman beings, both during growth and in adult life, the nifro-Jgenous balance is better maintained by rye protein than b y 'wheat protein. In the case of rye protein, too, we find tha tone of its constituents, gliadin, though faiily compute/it ft>maintain body weight,"7 is quite inadequate as a factor ofgrowth.a25> 4*3 The chief lack in rye protein would seem t obe lysin, but possibly tryptophan is likewise* wanting, for theaddition of small quantities of casein or still better of lar tal-bumin makes comparatively small amounts of rye proteincompetent to promote normal growth,wKl

Oats play a great part in modern dietetics. It is all thi»more interesting, therefore, to find that the strictlvf scientificexperiments of McCollum, Simmonds, and PiU/*A M Dshmtifand Mendd,7#. loXl and Abderhalden V> have proved clearlyand incontcstably that oat protein is incompetent to main*tain normal growth in rats. According to AUlerhalden, i t sbiological value is less than tltat of rye protein, Utickner,Nollau, Wilkins, and Castle *77 found t h t same thing in t h ecase of chickens, Sherman, Winter*, and Phillips** go *ofar as to say that the biological value of oat protein in humannutrition is no greater than that of m a k e protein, In oa t s ,as in the grains previously considered, it would wem t h a tthe proteins of the endosperm are of much lower grade t h a nthose of the whole grain.1011* By general agreement, gelatinis an adequate supplement to oat?*; but whereas Otbornc* andMendel 70 found that the addition of cstwiit sufficed to m a k ea diet of oats adequate, the experiments of McCollum in th i*direction gave negative results.

Barley, too, plays a notable part in modern dietetic*.But in this case likewise the unexceptionable experiments ofBucjcner and his collaborators *77 with chickens, and thoseof Abderhalden %* and Osborne and Mendel «»** with r a t s .

BIOLOGICAL VALUE OF VARIOUS PROTEINS 47

showed tha t when barley protein was the sole protein in thefood, growth was not maintained. This becomes explicablewhen we learn that hordein, one of the chief proteins in barley,contains no lysin, and is consequently quite inadequate.21?*us, 423 Apparently, however, the lacking tissue builders arepresent in the other proteins of barley, for with a diet con-taining 5 -4 % of isolated barley protein Steenbock, Kent, andGross 740 find that weight can be sustained, and that when thepercentage rises to 13-6 a slight growth begins. Accordingto Osborne and Mendel,73^ normal growth takes place whenthe food contains from 16 to 17 % of barley protein.

Recording to Hogan's researches,680 the kapirin of milletcontains too little lysin and cystin to suffice even for themaintenance of body-weight.

We see, then, that none of the cereal proteins are competentto maintain the growth of the animal body,3*9 and tha t onlya few of them (rye and barley) are adequate to keep up thenitrogenous balance in the adult. Since all the proteinsare different, it seems theoretically possible tha t in a mixtureof various sorts of grain there will be a mutual compensationof deficiencies. The experiments of McCollum and Simmondsshow that this compensation does to some extent occur, formixtures of the kind have as a rule a far higher biologicalvalue than the proteins of the individual cereals used inisolation.68**8a* Nevertheless, even the mixture of as manyas eight to ten varieties of grain proves incompetent to promoteperfectly normal growth, although such a mixture can ensurethe maintenance of body-weight. The reason for the inade-*iquacy is that the cereals have the common defect of containing!too little lysin and cystin, and in most cases too little trypto-jphan as well. Furthermore, the cereals contain too low a^percentage of protein, so that without isolating the proteinsit is impossible on an exclusive cereal diet t o ensure anadequate supply of these. In this connexion, we secureanalogous results as when inadequate mixtures of amino-acidsare used as experimental diets,54? for better effects are attainedby ringing the changes on different kinds of cereal proteins thanby persistent feeding ^uuith any one kind.*9s

Pea legumin in sufficiently high doses is able to maintainbody-weight,**5> 4*3 but is inadequate as a growth factor. The

48 VITAMINS

aggregate protein of peas is, on the other hand, utterly inade-quate, and according to McColIum and vSimmonds its biologica!value is very low.6^

In my own exper imen t s^ . *M, 7H, «»3 when haricot hmnswere used as the sole source of protein in the diet, even theapproximate maintenance of body-weight was impassible.McColIum, Simmonds, and Pitz636 also agree in forming avery low estimate of the biological value of bean protein ;the replacement of the protein in an adequate diet by onlyI 9 # 8 % of bean protein already suffices to upset the nitro-genous balance markedly. But a comparatively smalladdition of casein makes good the defects of bean proteinin a marvellous manner. In later experiments, McColIum andSimmonds 6s8 ascertained that bean protein and maize proteinare to some extent complementary, for one-third beans andtwo-thirds maize will determine a moderate amount of growth,which is, however, of brief duration, and is only half a*> extru-sive as the growth brought about by milk protein. Boyd l t87therefore takes a far too favourable view of bean protein whenhe ascribes to it an efficiency 60 % that of meat protein.

Very remarkable is the discovery of Adkinsi,11** that thegermination of beans greatly promotes the digestibility ofthe protein they contain ; but during the drying of the bean*this improved digestibility entirely disappears, Accordant i%the observation made by Johns and FinkH,lon that the additionof cystin to beans leads to no more than a trifling improvementin the value of bean protein ; but that when the beans arepredigested, cystin is an adequate supplement to their proti*in.Conflicting, however, with Adkins' observation is the furtherpoint made by Johns and Finks, that the addition of eystinrenders the bean protein adequate even when the beans havebeen boiled for a long time and subsequently rcdricd.

According to Osborne and Mendel,*^* w ihm phaseotinof beans is quite incompetent even to maintain the nitrogenousbalance of the animal body.

The same authorities inform us that the conglulin oflupines is equally inadequate. Accordant with this is t hefact that, in Abderhalden's e x p e r i m e n t s ^ lupines wereincompetent to maintain growth in rat*.

The vignin of the fodder pea, which makes up the gremttr

BIOLOGICAL VALUE OF VARIOUS PROTEINS 49

part of the protein of that pulse, is likewise quite inade-quate ™s* 423 ; and, speaking generally, Osborne and Mendel 665regard the protein of pulses as of an extremely low grade.But there is no rule without exception. Two of the pulses?have high-grade protein, the soy bean and the earth-nut.

Experimenting on rats, Osbbrne and Mendel 6l3 were ableto secure normal growth in these animals by feeding them withsoy beans. Elsewhere 665 they agree with Daniels andNichols 659 in describing the soy bean as a source of high-grade^protein suitable for human nutrition. Osborne and Mendel ai7were also able to secure normal growth by using glyceninisolated from the soy bean. Abderhalden, ^6 indeed, refers tothe soy bean as inadequate to promote growth in rats, butthe failure here may have been due to some other cause thanprotein insufficiency.

Daniels and Loughlin6Sl found that the aggregate proteinof the earth-nut (Arachis hypogaea) was of great value forhuman nutrition. According to Johns and Finks,Il89 in thecase of white rats, the replacement of 15 % of the wheatenflour in the food by earth-nut meal sufl&ced to secure nearlynormal growth; and when 25 % of earth-nut meal was used,growth was entirely satisfactory. It follows that earth-nutprotein must have twice the biological value of wheat protein.The result seems all the more remarkable seeing that arachinand conarachin, two of the chief proteins of the earth-nut,prove quite inadequate, whether given separately or in con-junction, and that they cannot be rendered adequate by theaddition of cystin, tryptophan, prolin, alanin, leucin, valin,or histidin. Sure suggests that the inadequacy of theseproteins may be due, not so much to the lack of this or thattissue-building constituent, as to some inner chemical peculiar-ities, som6 structural isomerism. We know of similar instances*Two of the amino-acids are readily saponifiable in one combina-tion, but in another combination are almost unsaponifiable.

Other adequate seed proteins are found in hemp seeds,pumpkin seeds, cotton seeds, and certain nuts. Thus, Osborneand Mendel report ai7 that hemp edesttn is competent tomaintain growth iti rats. But its efficiency is only one halfthat of lactalburnin,54i and is notably enhanced by the additionof a small quantity of cystin. 55°

4

50 VITAMINS

According to the same authorities, the globulin ofpumpkin seeds is a perfectly adequate growth factor.*25> w

Osborne and Mendel 493 were also able to maintain growthin rats by using cotton seeds as the only source of protein, andRichardson and Green SM report a similar success. Accordingto the last-named investigators,654 18 % of cottonseed meal inthe food suffices to promote growth; but if the proportionbe less than this, an arrest of growth occurs. They found,however/48 that the rats ' general power of resistance wasincreased and that the animals reproduced their kind morefrequently when, in addition, 5 % of casein was given. Con-formably with these results, it appears that the globulin ofcotton seeds, the chief protein of these, is an adequate growthfactor.*35> 4*3

Nuts are often recommended as an admirable nutrient(" vegetable meat " ) . The recommendation is confirmed bythe experiments of Cajori,1*66 who finds that (in rats) walnuts,almonds, hazel nuts, and pine kernels are competent to promotegrowth, development, reproduction, lactation, and the rearingof the young. Osborne and Mendel 2*5,433 report tha t theexcelsin of Para nuts is an adequate nutrient. Johns, Finks,and Paul8?* found that the globulin of the cocoanut was anadequate growth factor in rats, and that cocoanuts werealmost completely sufficient as the sole source of protein inhuman beings. Subsequently they ascertained tha t by theaddition of cocoanut, maize could be made an adequate foodfor human beings. But the hickory nut appears to containonly low-grade proteins, for, if growth is to be maintainedon a diet of these, two-thirds of the protein must be substitutedb y casein.1*66

L* Sugiura and Benedict,775 feeding white rats on bananas,were unable to secure normal growth. When pare caseinand a little yeast or extract of carrots were added to thebananas, normal growth took pla$e and reproduction waseffected, but a normal milk could not be produced on thisdiet. The effect of the casein does not depend upon a comple-mentary effect upon the protein, for meat protein cannot takeits place. In a later series of experiments,98° the sameobservers were able to confirm the adequating influenceof casein. Lewis,968 feeding guineapigs on bananas alone*

BI«L*GICAL VALUE OF VARIOUS PROTEINS 51

found that the animals died in from twenty to thirty daysfrom failure of nutri t ion; when oats, "bran, milk, or casein,and inorganic salts, were added to the bananas, the animalsthrove. Anyone accustomed to the critical study of experi-ments of this character will derive the impression that whatwas wrong with the exclusive diet of bananas was not theinsufficiency of the banana protein, but some other defect;perhaps there was not only a lack of calcium, but also a lackof the complettin A. Bailey Asford I29 relates tha t indigensconvalescing from yellow fever, eat nothing but bananas,consuming from thirty to forty of these fruits daily withoutany supplement whatever, health and strength returning in amarvellously short time. I have myself proved that , afterhabituation to the strange diet, it is possible to live very wellon bananas and butter, with a much lower consumption ofprotein than is requisite, for instance, upon a wheaten diet.

Feeding rats on potatoes, McCollum, Simmonds, and Par-sons 777 found that growth was insufficient, even when thepotatoes were supplemented with butter and salt. Theyestimate that the biological value of potato protein is onlyabout half that of cereal protein. But this report conflictssharply with the results of numerous experiments, lasting insome instances for years, made on human beings by Rubner,Thomas, Hindhede, and myself. These experiments showedthat potato protein was an adequate growth factor, and alsosufficed to ensure the maintenance of body-weight. In myown experiments, the biological value of potato protein was,,under certain conditions, even greater than tha t of meatprotein, and was surpassed only by that of milk protein and

protein. The discrepancy in the respective series ofobservations is perhaps explicable by the inadequacy of thesupply of inorganic salts in McCollurn's experiments. I t ispossible, also, that jpotato protein has verjr different biologicalvalues for different species of arumsjJte.

McClugage and Mendel,748 experimenting on dogs withcarrots and with spinach, found that the protein of both thesevegetables was quite inadequate. According to Brantz andSpillman,7^ when rats are put upon a diet of carrots, normalgrowth can (My be secured by the addition of casein. ^J

I t was mentioned above that conclusions as ^to the

52 VITAMINS

biological value of a protein determined by experiments uponanimals of one species are by no means necessarily applicableto animals of another species. A striking illustration of the*need for caution in this respect is afforded by the varyingeffect of yeast protein in human beings and in rats. Funk «mclMacallum/64 in conformity with Osborne and Mendd,^7report that yeast (supplemented with A in the form of but ter)supplies a protein which is a fully adequate growth factor inrats, and also suffices to ensure the reproduction of theseanimals. In human beings the result is different. Funk, th i stime in collaboration with Lyle and McCaskey,5*7 found t h a tfor the j iuman species the biological value of yeast protein isvery low. Wintz 53° had earlier come to the same conclusion,finding^that human beings could only tolerate the replacementof other proteins in the food by yeast protein up to an amoun tof from 20 to 25 % ; beyond that , a loss of nitrogen from thebody began. Hawk, Smith, and Holder *7* likewise reportthat in the human species the nutritive proteins can only besubstituted by yeast protein to the amount of from to to30 %—to say nothing of the fact that only very small quant i -ties of yeast can be administered to human beings withoutdisagreeable resul ts ; 4 grammes of yeast will inducediarrhoea.

5. T H E BIOLOGICAL VALUE OF THE ANIMAL PROTEINS.

Animal eggs resemble vegetable seeds in many respects,especially as regards their inorganic constituents. In thematter of the proteins, however, there must obviously be afundamental difference, above all when animal eggs a recompared with the seeds of cereals. Whereas the la t ter tktequite incompetent to function as adequate growth factor** inanimals, the animal egg must perforce contain everythingessential to the development of the growing animal embryo,Consequently, egg protein (as the sole source o^ protein)completely suffices for the needs of growing animals—rats,for instance.425 Even in very small quantit ies, it can fullycompensate the deficiencies of maize 393 or wheat.8?? Bu t theremarkable thing is, that both the chief proteins of the b i rd ' segg sxe adequate in this respect. Osborne and Mendel **5. «»*have proved it as regards viieUin; according to H a r t and

BIOLOGICAL VALUE OF VARIOUS PROTEINS 53

McCoUum,4<>9 and also according to Osborne and Mendel,349trifling amounts of egg-yolk can render maize an adequatenutrient. This power is mainly dependent on the abundanceof fysin and tryptophan in the yolk, bu t the cystin of theyolk must likewise play an important par t . Osborne andMendel 217> *2S> 423 also confirm the adequacy of ovalbumin,which is competent to ensure normal growth, and can inaddition make good the deficiency of maize protein,45° althoughnot quite so well as casein 568 (which is richer than ovalbuminin lysin and tryptophan), Maignon's observation 6^* I I28 thatrats, Myers and Voegtlin's observation 9ZI tha t rats, and Maig-non's observation 743 that dogs, cannot live on an exclusivediet of white of egg, does not conflict with the foregoing, forthe speedy death of animals in such extremely one-sidednutritive experiments is not due to protein insufficiency, butto a general lack of other nutrients, and especially of inorganicbases.

Blooi protein, like egg protein, is an adequate nutrient.Comparatively small quantities of i t suffice to make maizecompetent to sustain growth in the pig.346 According toHogan 568 its value largely depends on lysin and tryptophan,but also to some extent on cystin. Blood-serum, in especial,is so rich in cystin, that when casein (already fairly rich incystin) is used as the soured of protein in feeding dogs, a triflingaddition of blood-serum to the diet leads to a distinct improve-ment in growth.Il83 On the other hand, Maignon 6& finds thatfibrin is quite unsuitable as an exclusive nutrient for whiterats, and that this diet soon leads to the death of the animalsunder experiment; but I have frequently pointed out that ,since the aim of Maignon's experiments was to show tha t theanimal organism needs other nutrients in addition to protein,and that an exclusive diet of protein is poisonous, his experi-ments do not really tell us anything as to the respectivequalities of the proteins with which he experimented.

The rapidity of growth in mammals during the periodwhich immediately follows birth, suffices to prove tha t milkcontains an adequate protein, and indeed one of extraordinarilyhigh nutritive value. The quantities of this protein requiredin the food are marvellously small McCollum and Davis 4*5found that 3 % of milk protein (from cow's milk) in the*food

54 VITAMINS

sufficed to maintain body-weight in rats. An increase of thepercentage of milk protein in the diet was attended by aproportional increase in the rate of growth, until a proteincontent of 8 % was reached; an increase of the percentagebeyond this figure had no further influence on the rate ofgrowth. Owing to the presence of this high-grade proteinin milk, it is possible to make proteins, that are otherwisequite unsatisfactory, perfectly adequate by the addition ofsmall quantities of milk to the diet. Thus, McCollum andhis collaborators,^, 9°°> IJ43 feeding pigs on an exclusive dietof maize, found that the replacement of io % of the aggregateprotein in the food by milk protein resulted in growth becomingfairly satisfactory. When the substitution amounted to30 %, growth was perfectly normal. Sherman I05* obtainedsimilar results in human beings ; when adults are being givenan exclusive diet of wheat, maize, or oats, the replacementof onfy 10 % of the aggregate protein by milk protein sufficesto restore normal nutritive conditions. Like observationshave been made by others experimenting with wheaten diet 873and banana diet.968 Boyd I l 87 gives the relative biologicalvalues of cow's milk protein and meat protein as 96-5 : 100 ;in my own experience, milk protein has a decidedly higherbiological value than meat protein, both in adult and in younjsubjects. Edelstein and Langs te in ,^ experimenting 01children, found the following relative values : cow's milkcasein, 73 ; cow's milk lactalbumin, 82 ; aggregate cow's miDaproteins, 7 3 ; aggregate human milk proteins, 88. Fiirth^and Nobel J3°7 likewise found human milk proteins markedlysuperior to cow's milk proteins; the former contain so muchcystin and tryptophan that human milk, though its richnessin total proteins is lower than that of cow's milk, containsmore of these amino-acids than cow's milk. I t must not,however, be forgotten that full milk contains in addition toproteins a number of other bodies competent (even whenadministered in very small quantities) to exercise a powerfulinfluence in promoting growth. Hopkins,*0* for instance,experimenting on young rats, found that weight could noteven be maintained in these animals on a diet of casein, fat,carbohydrates, and sal ts ; but the addition of very smallquantities of milk (increasing the amount of dried matter in

BIOLOGICAL VALUE OF VARIOUS PROTEINS 55

the diet by only 4 %) sufficed to ensure normal growth. Wemay suppose that the chief cause of the improvement wasthat the milk provided complettins, and especially A, thatwere previously lacking in the diet. This is striking proofthat even a high-grade protein cannot sustain life in theabsence of a sufficient supply of complettins.

S«me earlier experiments on rats made by Osborne andMendel 217> ^s> 4*3 conflict with the foregoing, for caseinwithout the special addition of complettins sufficed to bringabout satisfactory development. But, in the first place,^the duration of the experiments was only 30 days, and thisperiod is too short to permit of valid conclusions being drawn;and, in the second place, there is some ground for assumingthat Mendel was using casein as ordinarily manufactured,i.e. an impure casein containing fairly large amounts of A.At any rate, Lewis, Cox, and Simpson Il83 found that in dogs,when a really pure casein was used, the results confirmedHopkins' observations on rats. Maignon's failure to securesatisfactory results by the use of casein as an exclusive dietin rats 64* and dogs 743, 941, «*8 {Sf a s previously mentioned,explicable on grounds which have nothing to do with thebiological value of the protein.

An additional proof that casein is a very high-grade proteinis furnished by the fact that proteins otherwise inadequatemay be made adequate by the addition of casein, sometimes invery small quantities. This has been demonstrated by experi-ments with gliadin,349 maize,409, 568* 578* 6l3, *>55* 658 wheat,579beans,636 carrots,784 and oats 736; but, as regards oats, seealso 6*5. According to Hogan, where maize is concerned,the addition of casein is more effective than that of whiteof egg. Even in the case of so high-grade a protein as cotton-seed protein, Richardson and Green 648 noted an improve-ment through the addition of casein, insomuch as the animalsunder experiment acquired a higher power of resistance, andtheir mortality was lessened. In the case of bananas,775»968, 980 too, the addition of casein to the diet was followedby marked improvement; but here a considerable part ofthe effect must be ascribed to the complettin A, which isalways present in casein as ordinarily manufactured, and tosome extent perhaps to the calcium in the casein. According

56 VITAMINS

to Osborne and Mendel,1082 however, the biological value ofcasein is only two-thirds that of lactalbumin.

In their earlier experiments on rats, Osborne andMendel 217» ^5» 433 found lactalbumin to be an especially high-grade protein. According to Emmet and Luros,879 protein-freemilk plus lactose plus 10 % of lactalbumin comprise anadequate diet, guaranteeing normal growth. But the twoobservers last named are mistaken in regarding the lactosein the protein-free milk as the growth, factor. Doubtless theaddition of carbohydrates is very important ; but Osborne'sresearches have shown that the effective factors in protein-freemilk are, over and above the complettins, chiefly the salts,and more especially the overplus of alkali in these. I n asubsequent paper,898 Emmet and Luros state that the biologicalvalue of lactalbumin is not impaired by drying or by pro-longed heating, even under 15 pounds' pressure. Accordingto Osborne and Mendel, 541 10 parts of lactalbumin will furthergrowth as efficiently as 15 parts of casein or 19 parts of edestin ;and in various other reports,55°, 6l3> 877, ^2 they emphasisethe superiority of lactalbumin to casein. Subsequent researchesby Sure I264 have, however, shown that the remarkably favour-able results of Osbome's experiments must be in part ascribedto errors in the quality of the supplementary extracts heemployed (the nitrogen content and the sulphur content ofthese). Exact experiment showed that chemically purelactalbumin, though rich in lysin 349 and extraordinarily richin tryptophan,I3»7 is poor in cystin and to some extent alsoin tyrosin. Osborne's protein-free milk contained 0*2 % ofsulphur, chiefly in the form of cystin, and also (with an aggre-gate nitrogen content of only 0-6 %) considerable quantitiesof tyrosin, whereby the lactalbumin was supplemented.Without protein-free milk, 18 % of lactalbumin in the dietproduced only poor growth; whereas a food containing nomore than 12 % of lactalbumin supplemented by only 0-12 %of cystin ensured normal growth. When the amount oflactalbumin in the food was reduced to 9 %, the addition ofcystin did not suffice to make growth satisfactory; but afurther addition of o-6 % of tyrosin made the diet adequatein this respect. These observations throw a new light on thesignificance of Osborne's protein-free milk, and furnish addi-

BIOLOGICAL VALUE OF VARIOUS PROTEINS 57

tional evidence as to the extreme difficulty of providingunimpeachable conditions in these experiments.

The experience of the war has abundantly shown thatwithin wide limits the composition of milk is independent ofthe food supply. As long as the requisite tissue-buildingconstituents are present in the maternal organism, the mothercontinues to produce milk of a definite composition. Thisapplies not only to proteins, fats, and carbohydrates, but alsoto complettins and inorganic salts. When the supply ofany tissue-building constituent is inadequate, the quanti tyof the milk falls off, but its composition is unaffected. Ofcourse this statement is true only so long as the maternalorganism can provide the requisite materials, and, more espec-ially, so long as no pathological changes have occurred inthe mother's organs. The lacteal glands have no more powerto synthetise arnino-acids than have the other animal organs.McCollum and SimmondsI0*6 expressly declare that if onlyone tissue-building constituent is entirely lacking, the secre-tion of milk is arrested. Through illness, however, and inthe human species through the inheritance of morbid predis-position, the lacteal glands may be so modified tha t evenwhen the diet is the best possible their secretion may bewanting, or they may furnish milk of abnormal composition.

F#r a very l#ng time, mi*b has been regarded as the bestsource of protein, and it is universally known that for humanbeings meat protein is perfectly adequate.337 According toOsborne and Mendel,663 this is true even when the meat hasbeen boiled and subsequently dried after expression of thejuices ; and Maignon 744 finds tha t the virtues of meat proteinare unimpaired when the meat has been boiled and thenextracted with alcohol and ether. The other animal organs,such as pig's liver,663 pig's heart, or ox's h e a r t y are adequategr#wth factors, and so is fresh or preserved fish,6l3,690 Never-theless, Lewis 653 finds that the value even of meat proteincan be greatly enhanced by the addition of small quantitiesof cystin. I t should, morover, be mentioned that my ownexperiments, as also those of P e z a r d ^ and Kraft,IO39 showthat meat protein does not suffice even to maintain nitrogenotisequilibrium unless the diet contains inorganic salts in definitequantities and proportions. This has, indeed, long been

58 VITAMINS

known. If a dog be fed on meat from which the juices havebeen expressed, emaciation ensues after a time, toxic symptoms

) set in, death speedily follows, and post-mortem examination5 shows in the skeleton the changes characteristic of osteomalaciaor osteoporosis. Carnivorous animals living in a state ofnature ensure a supply of inorganic bases by drinking theblood of their victims and devouring the bones and thecartilages as well as the flesh. I t also appears that wildcarnivora consume at times considerable quantities of fruits,leaves, and b u d s ; they do this especially in the autumn,whereas in the spring they live almost exclusively on animal food.

Boyd regards meat protein as the most valuable of allforms of protein,Il87 but this cannot be accepted as a positivefact as regards the protein of individual muscles, only asregards the aggregate protein of an animal body used as food.Abderhalden 45* learned this in his experiments on rats. Myown researches show that the aggregate protein of eggs, tha tof cow's milk, and to some extent that also of potatoes, aremore efficiently utilised than meat protein. In these experi-ments, however, the meat was given with an excess of acids.In some hitherto unpublished experiments made by Rose,in which care was taken to supply an adequate excess ofalkalies, meat protein was found to have a value approxi-mately equal to tha t of milk protein.

I t has long been known that the biological value ofgelatin is low. The older experiments that proved this havebeen confirmed by the comparatively recent work of Osborneand Mendel,**5> 4*3 Totani,600 and Lecoq.IO75> *°76 Gelatin ispoor in cystin, and therefore can be used to supplement proteinsthat are rich in cystin, or at least contain a fair quantity of thatsubstance, such as maize protein 598 or arachin.x*53 But gelatinis rich in lysin, and therefore very moderate quantities of gelatinenable it to supplement proteins that are inadequate becausethey contain too little lysin (such as wheat protein and oat pro-tein), thus converting them into adequate nutrients.598, &$, 736

6. T H E CONDITIONS REQUISITE FOR THE FULL EFFICIENCY

OF THE VARIOUS KLNDS OF PROTEIN.

A protein is not rendered adequate merely because allthe requisite amino-acids are present in it in sufficient quanti-

BIOLOGICAL VALUE OF VARIOUS PROTEINS 59

ties. Attention has already been drawn to the part thatmust be played by the mode of combination of the individualtissue-building constituents. Fischer and Abderhalden showedsome time ago that alanyl-glycin can be split up bytiypsin, whereas glycyl-alanin cannot be decomposed byferments. Some such peculiarity of composition may explainwhy arachin is so utterly inadequate a protein, althoughanalysis would seem to suggest that this substance ought tobe of high biological value. Similar conditions must accountfor the very inadequate way in which zein can be utilised byrats, even when it is supplemented by the addition of thelacking tissue-building constituents, whereas zein can beefficiently utilised after preliminary hydrolysis.600 Likeconsiderations must explain why freshly germinated beansare better digested than dried beans I I 6 6 ; why phaseolin cannotbe efficiently supplemented by cystin unless the phaseolinhas first undergone a tryptic digestion or has been boiled andthen redried IO94; why a mixture of equal parts of soy bean,wheat, wheaten bran, sunflower seeds, hemp seeds, and ryemeal (a mixture which is perfectly adequate in the crudestate), proves conspicuously inadequate after it has beenmade into a paste with water and then baked.877 In suchcases, therefore, the student of nutrition must have an eyeto these details.

I t is likewise necessary to point out tha t (in accordancewith the law of the minimum) when there is a lack of complettin,even the highest-grade albumin will be incompetent to promotesatisfactory development ™w* J*64 There is no means of ascer-taining the requirements of the organism as regards anyparticular constituent, unless in respect of every other conditionthe diet is all that can be desired.^, 664

On the other hand, in experiments on nutrition, it wouldbe a mistake to supply any constituent of the diet in quantitiesexceeding the optimal amount. There are two objections;4

first of all, this needlessly overloads the organism; and Jsecondly, it increases the minimal requirement of otherconstituents. The diet must contain a sufficiency of all necesJ

sary ingredients, but there must be no notable excess of any.For example, in experiments upon the effects of complettins,it would be a mistake to give an excess of protein in order to

60 VITAMINS

ensure that the results shall not be invalidated by proteindeficiency. Inasmuch, however, as the biological value ofthe different proteins varies enormously, and the minimalrequirement of protein will vary in accordance with the natureof the supply,836, 837, Io67, i*88 in such experiments the mostsedulous attention must be paid to the biological value ofthe proteins supplied in the food. Of course the best way isto have a preliminary series of control experiments in orderto ascertain the quantities of proteins that are necessary, orthe nature and amount of the requisite supplements.

The investigator must also bear in mind that the proteinrequirements vary at different ages. In adult animals andhuman beings, it suffices to give quantities of protein competentto maintain the body-weight throughout experiments ofconsiderable duration. During growth, however, very differentconditions prevail.*^* 423, 425 At this time of life, besides thequantity of protein needed to maintain body-weight, theremust be given enough protein to ensure that developmentand growth shall proceed at least as fast as if the animalwere free to choose its own food from an unrestricted supply.The first requisite, then, is a thorough knowledge of the normaldevelopment of the experimental animal under the mostfavourable conditions, and this presupposes abundant statistics,such as Robertson and Ray 483> 484 have supplied in exemplaryfashion in the case of the white rat Next, there must bean increase in the protein supply sufficient to provide for theincrease in the tissues. The requisite increase, again, variesat different periods of growth, and may at times be very large.In my own experiments^^ I found that the protein require-ment of the growing youth exceeded that of the adult maleby from 50 to 80 % ; Benedict,993 Holt,IXI7 and others recordsimilar results. In young persons from 13 to 19, during theholidays, the protein requirement is almost twicer as greatas that of adults.

In the earlier studies we are usually informed that thebasic turnover is lower in women than in men. To-day weknow this assumption to be untenable. At times, owing tothe catamenial losses, a woman needs more than a man, ofequal weight and doing the same amount of work, to maintainbodify equilibrium. I t will readily be understood that the

BIOLOGICAL VALUE OF VARIOUS PROTEINS 61

minimal requirement will rise considerably when reproductionand the rearing of offspring have to be provided for in additionto self-maintenance.995, I05* During the present chapter wehave repeatedly learned that a protein may be adequate forthe maintenance of body-weight, but inadequate for theneeds of reproduction and rearing.

As regards human beings, as early as 1913 I pointed outthat, when the conditions are in other respects optimal, theamount of protein requisite to maintain body-weight is farsmaller than has hitherto been supposed. American investi-gators have confirmed this contention when their experimentshave JDeen carefully designed. Boyd,Il87 for instance, givingmeat as the source of protein, estimates the minimal dailyamount of protein requisite to maintain body-weight at30 grammes; whereas in my own experiments, under moreaccurately adjusted conditions, the requirement was^^grajmnesof meat protein; and Rose, providing a better supply ofalkalies, found the meat protein minimum to be 24 grammes.Sherman, I05* in a critique of all previously published results,and after conscientiously making allowance for all accessoryfactors bearing on the various experiments, came to theconclusion that the protein requirement in a person weighing70 kilogrammes averaged 40-6 grammes (ranging from 30grammes to 50 grammes) ; being 0*58 grammes of proteinper kilogramme of body-weight. In another communication,^this observer declares that from 35 to 45 grammes of proteindaily (0-5 to 0*6 grammes per kilogramme of body-weight)are quite sufficient to maintain weight in a healthy humanbeing weighing 70 kilogrammes, even though the proteins benot carefully selected, nor of a specially high grade. A supplyequivalent to 1 gramme of protein per kilogramme of body-weight, when a mixed diet is taken (i.e. when there is nocareful selection of particular nutrients), provides a marginof safety of from 50 to 100 %. For growth and reproduction!larger quantities are, of course, requisite, and it is also desir-able in that case that the proteins should be of highbiological value.

CHAPTER THREE

T H E IMPORTANCE OF INORGANIC SUBSTANCES.

i . T H E SUPPLY OF A SUFFICIENCY OF NUTRITIVE

SALTS.

I N German scientific circles, the term " nutritive s a l t " isin bad odour ; its mere presence in a scientific essay sufficesto discredit the work. Nor was this attitude entirely un-founded, at one time. The importance of the proteins andof the supply of energy was so conspicuous to all studentsof human dietetics, that the importance of inorganic salts tonutrition was entirely overlooked by scientific observers.All the more, therefore, did these salts win the favour of thelaity and of quack-doctors ; they were regarded as a panacea,recommended indiscriminately for the relief of all troubles,from heartburn to cancer and consumption, so that nutritivesalt preparations sprouted in the market like mushroomsafter rain. We may question, however, whether the medicalprofession was well advised when, in the hope of checkingthe evil, it tabooed all reference to the problem. Beyondquestion the wiser course would have been to ask what firethere was behind so much smoke. The result of the taboowas that as recently as ten years ago not a single completeand accurate analysis had been made of the inorganic constitu-ents of any organ in man or the lower animals, of »any of thebodily juices, or of any of the excretions. Quite an outcrywas raised when at that date I ventured to maintain as much,and it is but a melancholy consolation that last year the factwas fully confirmed by the Experimental Stations Office inthe United States. Characteristic of the situation is it t ha t(wiljb. the exception of Rose's fundamental investigationsconcerning the calcium requirement of human beings, which

62

IMPORTANCE OF INORGANIC SUBSTANCES 63

were supplemented by the work of Emmerich and Loew)all the research in this field was undertaken by students ofanimal physiology, whereas specialists in human medicineheld aloof.

In excuse it may be mentioned tha t even when physiciansdid occupy themselves with the problem (as Heinrich Lahmann,for instance, endeavoured to do), no satisfactory results wereobtained. Trustworthy data could not possibly be providedby the analytical methods then available, in experimentalstations and experimental laboratories, for the inorganicconstituents of food and the organs of the body. More precisemethods of analysis had to be elaborated before such researchesofferSd any hope of success.

Naturally, therefore, the first studies of the complettinswere all affected for the worse by our ignorance of thesematters. Such skilful experimenters as Osborne and Mendel,or in Germany Rohmann, were entitled to congratulatethemselves when the animals under observation (rats) couldbe kept alive 80 days on an artificial diet. Even in Koch-mann's and Fingerling's researches, this ignorance had avery disturbing effect, and largely obscured the results.Rohmann tried numerous mixtures of inorganic salts beforehe at length secured a fairly satisfactory outcome. 4*, 7* Thesuccessful mixture is of historic interest, and its compositiontherefore worth recording here. I t consisted of: tricalciumjghosphate, 10 grammes ; bipotassiTmi_,phosphate^ 37 g , ;sodium chloride, 20 g . ; sodium citrate, 8 g. ; calcium lactate,§"g."; iron "Uffate, 2 g. The investigator who was ableempirically, out of numerous failures, to arrive at such amixture, must have been sagacious, and must have had thebenefit of wide experience. I t is especially significant tha tthe mixture contains an excess of bases, this excess amountingto 130*2 milligramme-equivalents in every 100 grammes ofthe mixture of salts, thus fulfilling what I have from thefirst regarded as an essential requirement of a properly arrangeddiet. Nevertheless, the mixture has grave faults. I t isoverloaded with phosphates and sodium chloride, and theratio betjveen potassium and sodium is only o -64 to 1 insteadof about 3 to 1. The ratio of calcium to magnesium is likewisefar too low, being only 0 -67 to 1 instead of 5—7 to 1. Further-

64 VITAMINS

more, the composition of Rohmann's mixture of salts sharesthe defects of almost all the mixtures hitherto recorded:it is completely lacking in manganese, zinc, and solublesilicates.

Osborne and Mendel J5° have shown that Rohmann'smixture is far from perfect. Their successes with a milkdiet led them to use protein-free milk as the provider ofinorganic salts. The milk having been acidulated withhydrochloric acid until all the protein had been precipitated,was then warmed and filtered, the clear filtrate being subse-quently neutralised with soda solution. In ioo grammes ofdry substance, this preparation contains: Ca, i ^92; Mg,0-20; Na, 2-18; K, 2-82; P0 4 , 3-52; Cl, 4-44; SO4/o-27.Hence 100 grammes of inorganic substances contain 934-2niilligramme-equivalents. In respect of excess of bases, asregards the ratio of potassium to sodium (1-52 to 1), and asregards the ratio of calcium to magnesium (5-9 to 1), therehas been great improvement. The method of analysis was,however, faulty. This is manifest at the first glance, for100 grammes of the preparation gave only 15-02 g. of " ash,"whereas the enumeration of the ions gives 15-35 g. Further-more, no determination was made of the other inorganicconstituents of the milk: iron, manganese, zinc, aluminium,and silicic acid. This is a typical instance of the defects ofthe analytical methods hitherto employed.

In view of Osborne and Mendel's results, it is interestingto recall that Heinrich Lahmann made the ash of cow's milkthe basis of his speculations concerning the inorganic saltsrequired by human beings, and that he was overwhelmedwith derision, mockery, and vituperation by his fellow-countrymen for his pioneer attempt to solve the problem.Instead of following up the line of research indicated byLahmaim, people made fun of him for " proposing to nourishadults as if they were infants-in-arms." The fiistory ofscience shows many strange aberrations!

The chief defect attributable to this first attempt is tha tin the work of Osborne and Mendel, and especially in tha tof Lahmann, the excess of bases in the milk was greatlyunderestimated. In both cases alike, and more particularlyin tBe analyses taken by Lahmann from the literature of the

IMPORTANCE OF INORGANIC SUBSTANCES 65

subject, the analytical technique was faulty, so that thequantity of alkalies was stated at too low a figure, and thepresence of iron, manganese, aluminium, zinc, and perhapscopper, was overlooked. Furthermore, there was a theoreticalerror in Lahmann's assumption which escaped all his oppo-nents, though some of them were on the verge of detectingit. Natural milk contains acid-rich proteins, and unless theseproteins are fully utilised by the body (as they are in thesuckling undergoing normal growth) the total surplus ofbases in the milk is not placed at the disposal of the organism—as it was in the American experiments with protein—freemilk. If the bodily requirement of protein is less than theamoiJnt of protein supplied in the food, then the acids in thesurplus protein will neutralise the excess of alkalies in theprotein-free milk. In actual fact, i t appeared in my ownexperiments 319 that when only so much milk was given aswould satisfy the bodily requirement of protein, the excessof alkalies in the cow's milk did not suffice either for the growingyouth or for the adult human being. In like manner, Lymanand Raymund,9fo experimenting on rabbits (which are verysensitive to acids), found tha t on a diet of cow's milk theanimals perished of acidosis; but when sodium citrate wasadded to the food, the acidosis disappeared and the urinecontained less ammonia; even when ammonium lactate wasgiven, instead of sodium citrate, the acidosis disappeared,and the urinary ammonia was reduced although an ammoniumsalt was being administered.

Following in Lahmann's footsteps, McCollum used theash of cow's milk for the supply of the necessary salts, bu thad to give very large quantities in order to secure tolerablygood results. Subsequently, instead of cow's milk ash, heused an artificial mixture of salts, which was somewhatbetter, but still contained too little alkali, and also had the samedefects as Osborne and Mendel's mixture. Moreover, the experi-ments of McCollum and his collaborators were too brief, andwere therefore less satisfactory than those of Osborne's school.

In later experiments, Osborne used a purely artificialmixture of salts, for too many sources of error were introducedby the presence of organic substances in the protein-freemilk. This mixture had additional merits ; and sindfe it

5

66 VITAMINS

appears to be the best yet employed, its composition may begiven: calcium carbonate, 134-8; magnesium carbonate,24*2 ; sodium carbonate (dried), 34*2; potassium carbonate,141-3 ; H3PO4, 103-2 ; HC1, 53*4 ; H2S04 , 9-2 ; citric acid(crystals), i r i - i ; iron citrate (crystals), 6-34; potassiumiodide, 0*02; manganese sulphate, 0-079; sodium fluoride,0*248; potash alum, 0-0245. Here the ratio of sodium topotassium has been improved, being now 3-2 to 1 ; and thenew mixture contains iron, manganese, aluminium, iodine,and fluorine. The ratio of calcium to magnesium is lessfavourable than it was in the earlier mixture, but this is aminor defect in view of the other improvements ; and althoughthe excess of alkali is reduced to about a third of whaf wasformerly present, a larger dosage with the mixture of saltswill to some extent compensate the deficiency. Two additionalerrors must be mentioned: there is far too little manganese(the quantity might well be multiplied by a hundred) ; andsilicic acid is not represented. If these defects were remedied,if the quantity of magnesium were somewhat reduced, andthe proportion of phosphoric acid lowered by a third, I shouldconsider the mixture thoroughly abreast of modern knowledgeof the bodily requirements of inorganic constituents.

None the less, the biological value of this nutritive mixturemay at times be improved by certain modifications, as by theaddition of bases that are inadequately represented in anatural diet—and especially when the addition changes anexcess of acid in the food into an excess of alkali. Thus Hart ,Halpin, and McCollum,612 feeding chickens on maize, Hogan,634feeding rats on maize, and Daniels and Nichols,659 feedingrats on soy beans, were able to ensure adequate growth bythe simple addition of potassium carbonate. As a rule,however, seeds of various kinds must be supplemented by thefttrther addition of sodium and calcium $45* 68a> *9X# 739; andwe have similar reports regarding potatoes,777 carrots,784and bananas.968 Even milk is well known to be adequatein respect of inorganic constituents only for the earliest periodof life; but for adults it is rendered adequate by the additionof a little iron. In niy own experience, however, as far asadults are concerned, the richness of milk in protein makesthe Excess of alkali in this food ijiadequate.

IMPORTANCE OF INORGANIC SUBSTANCES 67

In particular cases, special factors come into play tomodify the requirement for inorganic constituents. Especiallyinteresting in this connexion is the fact tha t cottonseed mealmanifestly contains a toxic substance which makes it quiteunsuitable as an exclusive diet, but t ha t this toxic substanceis rendered harmless by the addition of inorganic iron saltsto the food.66*

2. T H E IMPORTANCE OF INDIVIDUAL INORGANIC

SUBSTANCES.

There is still a great gap in our knowledge of the par tplayed by inorganic substances in metabolism and in animalphysiology generally. In addition to the inorganic substancesmentioned in the previous section, there are certain others,present more or less regularly bu t in far smaller quantities,whose importance still remains obscure. Any investigatorwho would bestir himself to throw light on the matter , wouldcertainly do good service. Some substances, such as therarer metals occasionally met with in various organs, maybe excluded from consideration as of no importance. But inthe case of any substance whose presence in the body isinvariable, two conflicting interpretations of its presence arepossible. We may be concerned with an element universallypresent in nature, though in very small quantities ; and wemay suppose that traces of this element are inevitably intro-duced into the body day by day with drinking water or withfood, and especially with vegetable food. Not until a certainaccumulation of such an element has occurred within thebody will the excretory organs take note of i t and proceed toeliminate it from the system. Bu t the problem tha t arisesis, whether such a substance (though present only in theminutest traces) is nevertheless essential to life and wellbeing;or whether it is merely a passenger, an ingredient whose entryis unavoidable but quite unimportant—unless, indeed, i tprove harmful to the organism when the quanti ty exceedsa certain minimum. Of especial importance is this questionas regards zinc, copper, and arsenic, which are always present,and even* in notable quantities. Although zinc is found incomparatively large quantities, the demonstration th^t i thas positive biological importance would be a new and sur-

6 8 VITAMINS

prising fact; but we have more inclination to supposecopper and arsenic may exert a stimulating influenceis of moment to life.

Although a mixture of inorganic salts containing no solsilicates, and perhaps no zinc, copper, or arsenic, maysatisfactory results in dietetic experiments, we mustinfer that the substances named are not essential toEven in the most carefully purified diet, traces of them :be present as impurities of the organic constituents. If ihave not hitherto been detected, the failure to find them iperhaps be accounted for, not by their absence, but byinadequacy of the analytical technique. Soluble si l icateespecial, are often present where least suspected. I t mmoreover, be remembered that the substances in questionpresent in the body in very minute quantities, which may g nally accumulate out of almost infinitesimal supplies in the f<

Earlier physiologists would have flatly denied tha t ahomeopathic doses of any substance could possibly bevital importance. To-day we have learned caution, sincehave, for example, in iodine a substance minute trace?which can exercise an extremely potent influence upon Intissue. Furthermore, the study of the complettins has hrmiquite a number of similar instances to light. Strictly sctific investigation can alone justify a decision upon smatters ; we must not jump to conclusions under the* sjmmere feeling. The rejection of possibilities withoutexamination has already wrought sufficient havoc bothbiology and in medicine.

Aron and Gralka *3^ have recently recorded the comption of a mixture of salts used by Aron in dietetic experimeiThe mixture is a good one in two respects: the excessalkali amounts to 743-1 milligramme equivalents ingrammes of inorganic ions ; and the ratio between caleiand magnesium is 4-8 to x. In other respects, howtnAron's mixture marks a step backward, for the ratio of po1sium to sodium is only 0-8 to 1 ; and the mixture contiineither manganese, aluminium (zinc), iodine, fluorine1,silicic acid. The reader may be inclined to think that Ioverdressing these criticisms. We must, however, perpetusbear in mind that the law of the minimum is fully applies

IMPORTANCE OF INORGANIC SUBSTANCES 69

to all the substances named. Should any one of them belacking, a perfectly normal development is impossible. Inas-much, moreover, as inorganic substances enter into importantreciprocal relationships (predominantly during excretion, butalso during the synthesis of organic substances), we areconcerned with a qualitative as well as with a quanti tat iveminimum. When, for example, a substance is being givenin quantities that are adequate per se, bu t another substanceis being also given tha t antagonises the former, the quanti tyof this is thereby rendered inadequate.

At an early stage of the investigation, this was recognisedby R6hmann,4*, 7* and also by Osborne and Mendel.^o Inanotfier paper,225 the last-named insist tha t for regular develop-ment something more is essential than a minimum of theinorganic constituents of a d i e t ; if development is to benormal, these mineral constituents must likewise be presentin the proper ratios one to another. Elsewhere,I224 Osbornehas recently insisted tha t our interest in the problem of thecomplettins must not lead us into the old mistake of forgettingother important factors. H e says tha t the need for the propersupply of inorganic constituents must on no account be over-looked, and he draws particular attention to the deficiency*of calcium and iron in many common foodstuffs. Lecoq I°47ifalso insists that the quality of nutrition is not solely deter-.mined by the amount and nature of protein, complettins,and the supply of energy, bu t tha t inorganic constituentsmust be provided in sufficient quanti ty and in the propermutual proportions. Scala *m reproaches physiologists whoare experimenting as to the causation of deficiency diseaseswith uncritically referring all the manifestations to theaccount of the complettins, and with forgetting tha t theorganic extracts they use in their experiments contain inaddition comparatively large quantities of inorganic sub-stances which likewise exercise a powerful influence. Aboveall we have to remember tha t when an extract is made fromuncoagulated material, chiefly the bases pass into solution ;whereas when the extract is made from material in whichthe protein has been coagulated by heat, acids predominatein the solution. This fact may in par t explain the reportedbehaviour of the thermolabile complettins.

7 0 VITAMINS

Reference may be made to the researches of FoiHalverson, and Schulz1188 as examples of the importancthe proper choice of a salt. I t is well known that pigson an exclusive grain diet do not develop properly. Sinceanimals ultimately become affected with osteoporosis,failure of development has been referred to the deficienccalcium in the food. If, however, j>rcpared I ) o n c a s l*chief ingredient of which is bicalcium phosphate—a third-]acid salt) be added to the food, not merely doe\s this faiinduce improvement, but it actually makes the disease wtOn the other hand, calcium carbonate, which function*the animal organism as an alkali, completely cures^trouble. The main cause of the disorder, and perhapssole cause, is, in fact, the acidosis evoked by the food,not a deficiency of calcium, for t h e bicalcium phosplireduces the alkaline reserve of the blood by 15 %, whcian equal quantity of calcium carbonate increases the alkareserve by 10 %.

3. T H E IMPORTANCE OF AN E X C E S S OF ALKALINE

SUBSTANCES.

American investigators have recently drawn attentionthe need, in this matter of the inorganic ingredients infood supply, that we should distinguish on principle betw<seeds and leaves.636» 658 Leaves contain an excess of inorgabases, whereas seeds contain an excess of inorganic acformers.8* w , 5°7, 5*4,578, *»• W, *>*$, *58> *>$% 6**> 6S*> &)** 7 ^ 7#,956 They have overlooked the fact t h a t in my tables 1^* *I found it possible to divide all foodstuffs into two classesaccordance with this principle : excess of acid is character^of all animal organs and every kind of muscular tissue, andf&ts, eggs, seeds, and buds ; whereas roots and tubers, s t aand leaves (" vegetables " ) , bulbs and fruits, are characters*by excess of alkali—cranberries being a notable exception.is therefore always possible, without monotony, to choosediet containing an excess of alkali. W e need merely rrthe acid and the alkaline nutr iments i n due proportions.

Of course this rule must not be applied too rigidly. Finstance, the study of Lecksucht [variously known in Englias " the lick," " p ica/ ' " wool-eating," etc.] in domesticat

IMPORTANCE OF INORGANIC SUBSTANCES 71

animals has shown that grasses, etc., which are ordinarilyrich in alkalies may in an unfavourable soil (such as moorlanddeficient in lime and potassium) acquire an acid reaction,and that animals which feed upon such pasture become seri-ously ill. In like manner, cultivated plants, when tooexclusively manured with nitrogenous fertilisers, and aboveall when treated with liquid manure poor in alkalies (Berg 3oS>e tc . ; Liechti and Truninger,282 ; Liechti and Rit ter I333) orwith ammonium sulphate, exhibit deficient alkalinity, andmay become positively acid.

No doubt the same rule applies to animals as to p lan t s :Natyre has once for all prescribed an optimum composition,which cannot be improved upon though i t can be changedfor the worse. In the previous chapter, stress was laid uponthe observation that, while the composition of the maternaldiet certainly has a notable influence upon the quanti ty ofmilk produced by a nursing mother, the quali ty of the milk,i.e. the amount of organic nutrients i t contains and the compo-sition of these, is substantially independent of the mother 'sdiet—so long as milk is secreted a t all and the mammaryglands remain healthy. These glands exhibit great energyin extracting the requisite materials from the maternal organ-ism, and the source of milk does not dry up so long as thematerials for the manufacture of the secretion are forth-coming. Rose 69> 7° has proved this also in the case of theinorganic constituents of the milk, especially as regardscalcium in goat's milk. McCollum and Simmonds I0*6 likewisedraw special attention to the fact.

When, however, noxious influences are a t work for a verylong time, they ultimately affect even the lacteal secretion.Hess, Unger, and Supple J33* found tha t when cows werestall-fed for a considerable period upon fodder poor incalcium, the aggregate ash in the milk was somewhat dimin-ished ; the reduction was especially marked in calcium andphosphorus, but the sulphur was somewhat increased. Thischange is parallel to that which occurs in plants when anacid grass is produced in a soil rich in nitrogen bu t poor ininorganic constituents generally. The question certainlyarises (and it is one which the experiments leave entirelyunanswered), whether such protracted deficiency of inorganic

72 VITAMINS

nutrients may not directly injure the lacteal glands, so thatthese can no longer be regarded as normal. Thus Rose 69, 7°found, in contrast with the data furnished by two years'experiments on goats, that in women the capacity for lactationruns fairly parallel with the calcium content of the drinkingwater ; in places where several years earlier a supply of softwater had been inaugurated, he ascertained that there hadbeen a notable decline in the period of lactation.

Let me take this opportunity of reiterating the warningthat , as regards the real need of the animal organism for anyparticular substance, brief experiments are absolutely value-less. Experimental animals may seem perfectly hea thy ,may develop and reproduce their kind, and only in the thirdor fourth generation do degenerative symptoms make theirappearance as the outcome of deficiency of some inorganicnutrient—control experiments showing that animals underthe same conditions, except that they are adequately providedwith this nutrient, remain quite free from these symptoms.From a communication made to me verbally by Urbeanu Ilearn that he saw barndoor fowls, provided with what seemeda bare sufficiency of calcium, develop for three generationsin a way that appeared perfectly normal; but the birds ofthe third generation were sterile because their eggs had noyolks. Control birds were still entirely normal in the fifthgeneration.

That is why the embryo has so vigorous a tendency tomaintain the calcium content of its own organism a t allcosts. I t is a familiar fact that during pregnancy a womaninadequately supplied with lime salts is apt to lose her teeth ;and, in bad cases of deficiency, she may even become affectedwith osteomalacia. According to the researches of L.Zuntz,861 the calcium content of foetal rats remains normalwhen the parent rats are inadequately supplied with limesal ts ; calcium deficiency in the food did not influence thecalcium content of the offspring of these animals unless thenoxious influence had been persistently at work long beforeconception. In such instances, however, the entire develop-ment of the offspring was seriously impaired.

I t seems expedient to remind the reader that the preparationof the food may also influence its richness in inorganic constitu-

IMPORTANCE OF INORGANIC SUBSTANCES 73

ents. I have already pointed out that , according to Frenchinvestigators, when milk is boiled the complex calcium-magnesium carbono-phosphate it contains is decomposed%

aiid is precipitated in an insoluble form ; and McCollum andParsons ^oo tell us that the precipitated salts cling to t hewalls of the container. Thereby the quality of the food i$doubly impaired. In the first place a natural inorganicproduct, directly assimilable and immediately available forbony growth, is metamorphosed into a form hard to assimi-late, and is in part actually eliminated from the milk. Inthe second place, and simultaneously, the excess of alkaliin th$ milk (already low) is gravely reduced. When, afterboiling vegetables, the water in which they have been boiledis poured away, the result is similar, inasmuch as the moresoluble bases are removed, so tha t even vegetables whichwere primarily rich in bases will exhibit an excess of acidafter such treatment (Cf. Berg 141, 333, 15^.) Finally, themedicinal administration of acids, whether aromatic acids oforganic composition such as salicylic acid and benzoic acidor inorganic acids such as boric acid and sulphuric acid, leadsto a dangerous loss of bases, inasmuch as these acids can onlybe eliminated from the body after combining with the inorganicalkalies it contains. +

In the previous chapter we learned tha t an excess of basesin the food is desirable were it only to ensure optimal condi-tions for the utilisation of the proteins in the diet, and toreduce the liability to the formation of noxious products ofmetabolism. I should like to refer here to the experimentsof Abderhalden,45* who found tha t alkalinisation of the foodwith sodium acetate brought about a more efficient utilisationof the protein in the food; and also to the observation ofBenedict and Roth 420 w h o noticed tha t in vegetarians(human) the basic turnover was less than in persons on amixed diet.

I t has long been known tha t when herbivora, and stillmore when rodents, are fed exclusively on grain, acidosisrapidly ensues. In rabbits on a maize diet, for instance, theacid urine contains far more phosphorus t han is being intro-duced in the food. Simultaneously the ammonia content oft h e urine is greatly increased, but Underhill 565» 566 states tha t

74 VITAMINS

in spite of this the animals' nitrogenous balance is maintained.The only possible explanation is that under the influence ofthe acids a vigorous production of ammonia ensues; thisbeing insufficient to neutralise the acids, the body, in its needfor bases, is compelled to turn to the osseous system, the lastalkaline reserve of the organism. Another familiar fact istha t an inadequate supply of food, or absolute starvation,,both of which lead to an enforced disintegration of the body's iown protein, give rise in herbivora to the same phenomenon'.that ensues upon an exclusive meat diet or grain diet, namelyacidosis, with alkali impoverishment of the body, and kreati-nuria. A remarkable fact is that, during the acidosis^ evenin the meat-eater, hypoglycaemia ensues, exactly as in thecase of direct poisoning, as for example by hydrazin sulphate.An injection of sodium hydrate will promptly render the urinealkaline once more and will simultaneously put an end tothe kreatinuria. , Inasmuch as in herbivora a grain diet alsQinduces acidosis, this disorder cannot, as is often maintained,be "the outcome of carbohydrate deficiency.

Rats, again, can only endure an exclusive grain diet fora short period, speedily succumbing on such a regimen. Anabundant addition of protein to the grain does not help them.Hogan, however, tells us that an addition of alkalies preservestheir life and has a marvellous effect in furthering growth.

Hart , Miller, and McCollum^s and Abderhalden andEwald 683 have shown that an excess of acid in the food mustoften play a part in the causation of the avitaminoses; inthe later chapters of this book the fact will again and againforce itself on our attention. Peckham J310 stresses the rela-tionships and reciprocal actions of inorganic nutrients andcomplettins. In this connexion we may allude to Aulde'sobservation I259 that when there is either a lack of calcium oran excess of acid in the food, the complettin A is void of effect;and tha t conversely the assimilation of calcium and the fulldevelopment of the anti-inflammatory properties of this baseare only possible in the presence of A.

According to Steenbock, Nelson, and Hart,4i° the directaddition of acid to the food always causes an increased excre-tion of ammonia in the urine and a decreased excretion ofurea In omnivora and carnivora this decline in urea is said

IMPORTANCE OF INORGANIC SUBSTANCKS 75

to take place by way of compensation, and these authorstheiefure assume that in such animals an abnoimal di inte^m-ticn of the protein in the food already takes place in theintestine, accompanied with tin4 fox mat inn of ammonia, andthat the body protein remains intact. In herbivora, on theother hand, it is supposed that the taking of acids with thefood involves also the disintegration of the body protein, sothat the formation of ammonia is increased to a greater extentthan the formation of urea is diminished, and the nitrogenousbalance becomes negative. In criticism of thc\s«* experimentsI must point out that the diet was not one in which theingestion of nitrogen had been reduced to a minimum, andthat their duration was too brief. Had it U r n otherwise Iam sure that the observers would have* found, as Rose andI found, that in human beings, and in omnivora and eatnivora,direct losses of nitrogen occur in sueh conditions.

We have to remember that dogs and pigs, as normallyfed, receive far more protein than is essential far t h m minimalbodily requirements, and that thereby a quant i ty of ammoniacompetent to neutralist* the acids added to the food is liberatedwithin the system. If no more protein than the indispensableminimum had been given, and if the requisite* supply of addi-tional energy had been provided by giving fats and cat bo*hydrates, the consequences of the addition of acids to thefood would have been promptly manifest in these animals too.

Hopkins l 0 « points out tha t tinder ceitain rondit iomaddosis can be: partially relieved by an abundant supply ofprotein, thanks to the extensive formation of ammonia outof the surplus protein. Hut wi: must not go too far withthis supply of protein, for Maignon has shown again and againtha t an exclusive protein diet is positively toxic: even in acarnivore. Whipple and van Slyke?*1/ had similar irMtlts intheir experiments. Feeding on large quantified of meatcause* symptoms of unite poisoning resembling thme t*ra-t ioned by an injection of altnunosf*, a t tended hv similarconditions in the blood™ tho^e charac tefki i r of t$v*ucdestruction. In collaboration with Birkner I have nhown *ntha t this decomposition of the tissues must atisi* from thischanges in the bodily juices determined by an execwiveproduction of ammonia.

76 VITAMINS

4. ACIDOSIS.

Given certain conditions, it does not take much to induceacidosis. Bossert I0I4 points out that * in children with apredisposition to spasmodic affections (and only in these)the mere addition of one egg to the daily diet will give riseto oedema with retention of nitrogen and inorganic constituents,and sometimes to the occurrence of carpopedal spasms.When the egg is withheld, normal conditions promptly return.Manifestly in such cases the existence of an affection of thenervous system explains why the acidosis has so powerfulan influence; and we must invoke the same explanation toaccount for various observations that, in cases of severediabetes, epileptiform convulsions occurred as soon as acidosisset in.I044, «74, "75 (Cf. also Elias W.) Shaw I I 8 2 likewisefound tha t when certain nerve degenerations were present,acidosis arose more readily and had a more powerful effect—as for instance in epilepsy, severe malaria, chronic melan-cholia, and chronic alcoholism. In conjunction with theacidosis, " epileptic " paroxysms occurred, especially duringthe night, when the reaction of the blood is physiologicallyless strongly alkaline than during the day. At the same time,the blood exhibits a marked excess of hydrogen ions. Insuch cases, an increase of protein in the food leads to anincrease in the frequency of the paroxysms, whereas theadministration of alkalies reduces their frequency. Atthe post-mortem examination in cases of acidosis, therewas found cloudy swelling of the pia-arachnoid, such as iscommonly observed after death from poisoning by the mineralacids.

Although in various skin diseases (psoriasis, acne, eczema,and seborrhoic dermatitis) the acidity of the blood and theurine is sometimes found to be increased. Sweitzer andMichelson II04 state that this is not invariably so, and theytherefore regard acidosis as at most an accessory factor ofthese diseases.

As a general rule, we have to reckon only with theinorganic acid-formers as the originators of acidosis. In mypublished works, however, I have repeatedly insisted thatwhen an excess of organic acids is taken, so that the organism

IMPORTANCE OF INORGANIC SUBSTANCES 77

is unable to effect their complete combustion into carbonicacid and water, they must have precisely the same effect asthe inorganic acids, seeing tha t they too must be neutralisedby inorganic bases before they can be excreted. Thus inhuman beings the immoderate ingestion of dilute acetic acid(table vinegar) or citric acid (lemon juice) may lead to typicalsymptoms of acid poisoning, as may unfortunately be oftenseen in persons who are undergoing the popular " lemoncure.1' Obviously, too, an immoderate supply of carbohydratesmay arouse like manifestations, if these food-stuffs undergoacid fermentation in the bowel. Indeed Barr IO55 regardssome pi the symptoms of beriberi and of experimental poly-neuritis as consequences of an acid poisoning due to theintestinal fermentation of the carbohydrates tha t are tooliberally supplied in the food. I t is far from improbable tha tthe so-called " Mehlnahrschaden" of infants-in-arms isin part dependent on similar causes.* This explains whyDreifus Io65 found that in the rabbit the rectal administrationof dilute organic acids in quantities tha t were tolerated bymouth, proved fatal. The acids were quickly and directlyabsorbed into the blood through the mucous membrane ofthe large intestine, whereas when taken by mouth they couldenter the blood only through the devious route of thelymphatic system, and could on the way be neutralised—partially at least.

There are also numerous reports to the effect that theabundant ingestion of fat may lead to acidosis. This is wellknown to occur in diabetics, whose powers of oxidation arein any case impaired. We must, however, bear in mind tha t

• Detailed accounts of the syndromes known in Germany as Mehlnahr-schaden and Milchnahrschaden will be found below, p. 295 and p. 297.They are nutritive disorders in bottle-fed infants, respectively due to feedingwith cereal food and with diluted (usually pasteurised) cow's milk. Itneither becomes us nor behoves us as translators to rush in where Britishexperts fear to tread. The leading British authorities on the diseases ofchildren have failed to differentiate what the Germans call Mehlnahrschadenand Milchnahrschaden from the generality of cases of infantile marasmus.That is why we have to use the German names in the text. The lack ofsuitable English terms dates from ten years back. In 1913, Casimir Funk,at that time director of tbe physiologico-chemical laboratory of the CancerHospital Research Institute in London, wrote: " In English pediatricliterature, the concept Mehlnahrschaden is quite unknown, the disorderbeing usually included under the heading atrophy. . . . Milchnahrschadencertainly belongs to the same category of nutritive disorders " (Die Vitamine,Bergmann, Wiesbaden, 1914).—TRANSLATORS' NOTE.

7 8 VITAMINS

as regards fats there is a difference in the mechanism by whichacidosis can be produced. The splitting up of fats, with aconsequent liberation of fatty acids, takes place in the intes-tine. Since, as far as we know, free fatty acids cannot beabsorbed by the intestinal epithelium, the neutralisation ofthese acids must be effected within the intestine itself atthe cost of the alkalies in the bile. Of course this, too, leadsto alkali impoverishment. The only difference is in theplace where the loss of alkalies occurs; the net result is thesame.

Uhlmann « l 6 reports instances of obstinate acidosis insevere cases of diabetes, in which the regulation of the f.arbo-hydrate supply no longer leads to any improvement, but areduction in the amount of fat ingested is followed by areduction in the excretion of acetone. In like manner, Bierryand Portier 73* and also Dubois 733 report that in rats theweight can be maintained by a diet of coagulated protein,fat, carbohydrates, and salts, in definite proportions; butthat when the proportion of fat is unduly increased, acidosisensues, leading to acetonuria and emaciation.

In view of the observations made by all other physiologists,it is rather presumptuous of Bayliss »3* to assure his reaciersthat the notions of acidosis and alkalosis are apriori untenableand to declare that other explanations must be found for themanifestations classed under these names, seeing tha t aslong as the organism is alive it is perfectly able to compensatesuch noxious influences!

Confusions of this kind arise mainly from a lack of precisionin the definition of acidosis. This, in turn, results from themixing up of two ideas which to some extent are entirelydistinct, the confusion having taken place during the earlyenthusiasm of the "ionic d a y s " when investigators werefull of the joy of creation and discovery. In experimentswith pure salts it appeared that acidity or alkalinity corre-sponded with the H or OH concentration, and " reaction "incontinently identified with " ionic concentration.0 Inreality, we chemists understand something more by reaction,namely the power of neutralising an acid or a base ; and inorganic chemistry numerous substances are encounteredwhich unquestionably possess a chemical reaction in this

IMPORTANCE OF INORGANIC SUBSTAIsTKS 79

sense, and can certainly function as acids or bases, althoughthey do not appear to bo ionised.

A t tha t t ime, a t tempts wcini made to tlehw tlict conceptof acidosis, in accordance with the ionic cloctrtiu1, in terms ofthe physical relationships in the blood; but these at temptswere unsuccessful. We distinguish in the* hhm\, Jixs»t of all,the hydrogen concentration, whirl* must 1><: regarded as themeasure of the physical reaction. This concentration isextraordinarily constant, remaining unchanged even whenlarge quantities of free hydrochloric arid am aclnnuistrmlNot uati l the aciclotic condition approaches i ts term {;IH infatal poisoning with a mineral acid, or in diabetic coma)<loes tfte hydrogen ionic concentration become positively arid.I t is evident, therefore, that the Mood mwA contain MiUstantescompetent to neutralise acids without any ch.ingc; in theIonic concentration. The most important of these buffersalts in the blood is sodium bicarbonate1, ami next nniWH thephosphate in the blood. As an index of this rcsctrve alkalinitywe can use the carbonic-acid tension in the alveoli ar in theoxalatc plasma, or the ionic concentration in the plasma*on the addit ion of measured quantit ies of acid*.

Poxges, Leimdftrfer, and Markovici1*^ ^n regard thecarbonic-acid tension of the blood an the most roiiahkt signof acidosis. Van Slyke, Culk*nf and Stil!iuan4i7 report tha tin acidosis there is no change in the ionic coxuamtratirm ofthe blood, b u t that its reserve alkalinity ia rrrlucrcl, thinfinding expression in \he diminished carbonic-udd trnsicm inthe alveoli. Begun, Herrmann, and MiJn/.cr^o lh\t\¥ an Hutother liand, in an extended sorictK of rcsfardi^s that l»jg«quanti t ies of hydrochloric acid can be a d i n i n h t w d with tintfood, leading to a marked increase in the (»xcr«ttion ot anmirmiain the urine, without the occurrence in the hioorl o( anyreduction either of the ionic concentration or of tb« n^ rv r*alkalinity as manifested by the carbonic-acid tension. Natunti l large doses of acid have been given for a v i ry lemg timi%and when a general alkali impovednhmefit hax takrri pkiCDthroughout the body, docs the carbonic-acid tfiwiau th%Um\and moreover this decline seems to be evoked by grave timmalterations. These authors ' r e w a r d s lead tlwin to thecoaclusion tha t t h e carbonic-acid tension in the sdvaili i t

80 VITAMINS

primarily dependent upon the carbonic-acid content of thevenous blood, that is to say upon the aptitude of the blood totake up carbonic acid. Consequently, this tension cannot be anindex of the acidosis, and can decline in the absence of acidosis.

Conversely, an increase in the reserve alkalinity of theblood does not indicate the existence of alkalosis, for suchan increase may occur physiologically, as during digestion inconsequence of the secretion of hydrochloric acid by the stomach.(Cf. van Slyke, Cullen, and Stillman438.) Nevertheless, thealkalinisation of the blood in such circumstances will notincrease beyond a certain measure, for fresh acids are con-tinually being supplied in the food, and moreover the hydro-chloric acid that has been secreted in the stomach isreabsorbed. However, grave alkalosis can be induced byrepeatedly washing out the stomach during the climax ofgastric digestion, so that the hydrochloric acid is removedfrom the body and cannot be reabsorbed. McCollum and hiscollaborators I0I° saw severe tetany produced in this wayin cases of stricture of the pylorus.

Following the example of leading authorities, we maydescribe acidosis as a condition characterised by a deficiencyof fixed inorganic bases in the body, leading to the increasedproduction of ammonia. According to N. Zuntz, the increasedexcretion of ammonia in the urine, in conjunction with highacidity of the urine, is the only certain sign of acidosis. (Cf.Steenbock, Nelson, and Hart,4<>7,410 and also Lyman andRaymund 962.) Many observers, such as Shaw,1100 regardacetonuria as a sign of acidosis. But it is certain that theremay be severe acidosis without acetonuria, and it is conceiv-able that acetonuria might occur in the absence of acidosis.Hopkins IO24 is also right in pointing out that the morbidformation of oxybutyric acid, acet-acetic acid, and acetone—a condition which can best be separately described as" ketosis "— must be clearly distinguished from the changesin the physico-chemical equilibrium which lead to a diminu-tion in the reserve alkalinity of the blood and to a declinein its capacity for neutralising acids.

Hopkins also draws a distinction between uncompensatedacidosis, in which there is a real increase in H-concentration,and compensated acidosis, in which no change in H-concentra-

IMPORTANCE OF INORGANIC SUBSTANCES 81

tion can be demonstrated. I n chronic nephritis and otherkidney disorders, the ordinary protective apparatus of thebody (the buffer salts of the serum, the elimination of carbonicacid by the breath, and the excretory activity of the kidneys)is thrown out of gear because the production of ammonia isdisturbed, and there ensues an acidosis of renal origin, whichis usually uncompensated. Nitzescu 406 and Palmer andHenderson 434 make the same distinction.

In the light of extant knowledge, it would seem to be amistake to concentrate attention upon the composition ofthe blood. Very serious disorders may occur in which thecomposition of the blood appears perfectly normal. The bloodcertainly possesses to a very high degree the power of self-regulation, but this does not suffice to explain all thephenomena we are considering. I t is necessary to assumethat a hitherto unmentioned regulatory apparatus is at thedisposal of the blood. We learn this from the frequentlyascertained fact tha t in long-continued acidosis the bodyexcretes less phosphoric acid and sulphur than is ingested,bu t that when in these circumstances fixed bases are addedto the food, the balance of phosphorus and sulphur inclinesstrongly in the opposite direction. I t follows that the bloodmust have temporarily deposited somewhere or other theexcess of acids in the food which could not be eliminated bythe kidneys or the bowel. I t should also be noted that inthese conditions there is a simultaneous retention of nitrogen,which is likewise excreted as soon as a sufficiency of basesis administered.

Normally, it is probable t h a t these substances, whichpossess a rather high molecular weight, are not retained inthe blood itself, or can exist there only for brief periods, whengreatly diluted. The accumulation of such residues in theblood would certainly have bad effects, and since in the condi-tions we are considering they cannot be excreted in the urine,they are deposited wherever they will do least mischief.Suitable depositories are offered by the comparatively inactivetissues, such as bone, cartilage, and connective tissue* Afavourite site is the subcutaneous connective t i ssue ; and itis here, too, tha t sodium chloride, an excess of which is com-monly ingested, is stored pending opportunity for the excretion

6

82 VITAMINS

of the surplus. Purely theoretical considerations convinceus of such possibilities, and theory has now been confirmedby the numerous investigations of recent years. But theexplanation of the process is found, above all, in two physio-logical peculiarities of such tissues, peculiarities by whichthey are sharply distinguished from the more active tissues.

In the first place, I may remind the reader of a fact which,though it was discovered forty years ago, has again and againbeen forgotten, namely that, whereas sodium salts and oftenamino-salts exert a paralysing influence on nerve and muscle,potassium salts have a stimulating effect. A discovery madeby Gerard *43 gives unexpected confirmation of this. He foundthat functionally active organs crowded with cells, such asthe muscles, the heart, the testicles, the kidneys, the liverand the brain, are comparatively rich in potassium, whereasthe blood, the skin, the arteries, the lymphatic glands, cartilage,and bone, are comparatively rich in sodium. These inactiveor almost inactive tissues are less injured by a fairly highsodium content, and it is a logical inference that they willalso be the depositories for nitrogenous acid residues of highmolecular weight.

This tendency to deposit noxious substances in regionsof minor physiological importance is reinforced by thephysiological proclivity of the connective tissue towards thestorage of salts, and especially acid radicals of high molecular

IMPORTANCE OF INORGANIC SUBSTANCES 83

by increased storage of fluid in the tissues. The depositedmaterials carry with them so much water (infiltration of thetissues) that the percentage content of chlorine (for instance)is perfectly normal, and the retention does not become apparentuntil the contents of the tissue are reckoned in the dry state.(Cf. Scholz and Hinkel 377 and Rothstein 83<>.)

5. PARADOXICAL E F F E C T OF CALCIUM SALTS IN THE

ORGANISM.

These peculiar relationships furnish the key to manyenigmas in the metabolism of the inorganic constituents offood, «t>ut a more detailed discussion of the topic would takeus too far from our proper subject. Moreover, it will benecessary to return to the mat ter in a subsequent chapter,so the foregoing brief indications must suffice for the presentIn the same connexion, however, it is necessary to refer brieflyto a special instance of inorganic metabolism, one whoseapparently paradoxical developments must become familiarto anyone who wishes to understand and accurately toappraise many of the experiments made in the course of moderndietetic research.

In the chemical laboratory it is possible by the additionof neutral salts to effect extensive modifications in ionicconcentration, these modifications usually taking the form ofa diminution of hydrogen ionic concentration. In the livingorganism we are unable to do this, for, as already said, thebody has a t its disposal a regulatory apparatus which is somanifold in its possibilities and which acts with such prompti-tude tha t the effect of doses of mineral salts is completelyobscured. There is, however, one exception, which seems allthe more amazing inasmuch as in this instance the administra-tion of a neutral salt ultimately leads to an increase insteadof to a reduction in the hydrogen ionic concentration. Thefinal upshot of the consumption of this salt by an animal isthe occurrence of marked acidosis. To the chemist i t is a tonce obvious tha t the cause of this remarkable result cannotbut be some kind of reaction which in the living organismpursues a quite anomalous course—however loath we maybe, a t the first glance, to entertain the notion tha t thechemical laws of the living organism can be different from those

84 VITAMINS

of inorganic nature. In 1905, when I first drew attention tothe paradox and explained it with the use of chemical formulas,my exposition aroused universal scepticism, for its improb-ability seems overwhelming. In essence, however, theexplanation involves nothing extraordinary, nor does it entailany contradiction of familiar experience or demand theacceptance of a new system of kinetics in organic chemistry.I t merely requires us to make due allowance for the fact t ha tthe animal organism is, after all, something very differentfrom a test-tube; and that the chemical reactions t ha t takeplace within it result from the collaboration of millions ofcells which, despite their interdependence, are to a # largeextent autonomous, so that each is competent to act after itsown fashion. If we study the chemical reaction in theindividual cell, we find the familiar laws in operation ; and itis only the collaboration of numerous cell complexes whichproduces an aggregate result that amazes us by its apparentlyparadoxical character. In other words, the ultimate resultis not the outcome of a single reaction but of a series of reactions,and these reactions (here is the core of the matter) t ake placein various organs.

I am far from having been the discoverer of theseremarkable reactions. I merely gave the explanation offacts which had long been known, though their peculiarityhad not been noticed by previous investigators. Earlier inthe present chapter one of these well-known facts was touchedupon. I mentioned that Forbes, Halverson, and Schulz n 8 8

found that acidosis was increased by administering bicalciumphosphate and diminished by administering calcium carbonate.There is nothing remarkable in this, seeing that bicalciumphosphate, CaHPO4, is a third-part acid salt. The remarkablepoint only conies to light when we know tha t we are dealinghere with a special instance of a general rule, and when welearn that with the exception of calcium carbonate and tri-

l

IMPORTANCE OF INORGANIC SUBSTANCES 85

The strange and anomalous behaviour of calcium is explainedby an observation made a great many years ago. ErnstLehmann 4, 16 d r e w attention to the fact that the administra-tion of calcium salts leads to no more than a trifling increasein the calcium content of the urine. Still earlier, Riesell z

had shown that when calcium salts are given by mouth, thequantity of phosphates in the urine diminishes; and thisobservation was confirmed by Schetelig * and all subsequentinvestigators. Noorden X5 and his pupils Strauss ™> 2I andHerxheimer2 2 found, however, tha t the administration ofcalcium carbonate reduces the acidity of the urine, and thatthe reduction in the urinary phosphates depends upon theexcretion of tricalcium phosphate by the bowel; wherebythese observers were led to the erroneous assumption tha t thecalcium combined with the phosphoric-acid radical in thecourse of intestinal digestion. Nevertheless they recognisedthat a portion, a t least, of the calcium phosphate must beexcreted by the mucosa of the large intestines. Herxheimeralso recognised that the aggregate excretion of phosphatesis hardly altered by the administration of calcium. What,happens, then, is that , when calcium salts are given, a 'partiof the phosphoric acid which would otherwise he excreted by the \kidneys is diverted to the colon ! My own researches likewise *showed tha t the greater par t of the calcium is excreted bythe intestine in the form of tricalcium phosphate.97' 356

In the urine, however, the phosphoric-acid radical isexcreted as bisodium phosphate, or (as many think) in partas monosodium phosphate. The relationships, therefore, canbe expressed by the following equations:

r. 3CaCl2 + 2NaH 2 P0 4 = Ca 3 (PO 4 ) a+ 2NaCl + 4HCI and2. 3CaCl2 + 2Na 2 HP0 4 = Ca3(PO4)2 + 4NaCl + 2HCI.

Of the results of these reactions, the tricalcium phosphateappears in the faeces, and the sodium chloride in the urine.Since free hydrochloric acid cannot exist in the blood or thetissues, it immediately undergoes a reaction with bisodiumphosphate :

3. 2HCI + 2Na a HP0 4 = 2NaCl + 2NaH 2 P0 4 .

The net result is tha t dosage with the neutral salt increasesthe acidity of the urine.

8 6 VITAMINS

B u t "before the excretion occurs, the hyperacidity hast a k e n effect within the organism, for Fuhge (op. cit.i, andI myse l f a t an earlier date, found tha t the administration° f s a l c i u r a chloride led t a a n increased production of ammonia,

T h i s is only one aspect of the paradox. The other aspects e e r n s almost crazier. Large doses of calcium chloride induces e v e r e losses of calcium, which may culminate in osteoporosisa n d osteomalacia in the experimental animals. T h u s Etiennew o r k i n g alone,*3° and working in conjunction wi th Fritsch,?6

f o u n d tha t chloride of lime does indeed induce a t the outseta.n accumula t ion of calcium "within the body ; bu t t h a t if i ti s g i v e n for a long time, i t induces severe losses of calcium,a n d t h a t bone deformity may ensue; these evil results c>egmi m m e d i a t e l y if adrenalin or potassium iodide is given togetherw i t h t h e calcium chloride. Similar results Lave recentlyb e e n secured in Germany. The explanation has already beeng i v e n . The calcium chloride induces hyperacidi ty withint h e organism, and this leads in the long run to so serious ana l k a l i impoverishment tha t the last alkaline reserves of theb o d y , those in t he osseous system, are a t tached and passi n t o solution, in order tha t the acids may be neutralised byt h e ca rbona te s derived from the bones.

T h e fundamental cause, then, is the diversion of thephosphor i c -ac id radical from the kidneys to t he intestine,a n d t h e consequent transformation of t he bisodium phosphatei n t o monosoditun phosphate. I t follows tha t all the calciums a l t s containing acid radicals tha t are incombustible within,t h e o rgan i sm must act in the same way—for instance, thec a l c i u m salts of the aromatic acids. To some degree, however,s u l p h u r i c acid is an exception, for the organism can get ridof s u l p h u r , not only in the form of sulphuric acid, bu t also( i n p a r t , at least) as ester sulphuric acids which require onlyh a l f t h e amount of alkali t o neutralise them, or as non-acidc o m p o u n d s . Rose's experiments do in fact show tha t theu r i n a r y acidity is not so greatly increased by dosage withc a l c i u m sulphate as by dosage with calcium chloride. As p e c i a l exception is calcium carbonate, whose acid radicalc a n b e freely discharged in t h e gaseous form through thel u n g s , s o that no bases are requisite to assist in i t s excretion.T h e s a m e considerations apply t o the calcium salts of the

IMPORTANCE OF INORGANIC SUBSTANCES 87

combustible organic acids, seeing that the terminal productof their combustion is likewise carbonic acid. In both cases,therefore, the entire calcium content of the salt remains a tthe disposal of the organism as a base.

I t is t rue t ha t the hydrochloric acid of the stomach convertscalcium carbonate into calcium chloride. Bu t this (loos notintroduce any new hydrochloric acid into the body- When-ever hydrochloric acicl is formed in the stomach, a corre-sponding amount of alkali is set free, and this is competentt o neutralise the hydrochloric acid that is liberated when the*calcium is excreted as tricalcium phosphate, so that the wholebasic content of the calcium carbonate is, after all, availablefor the organism.

The inorganic magnesium salts exhibit the same peculiarityalthough not to so marked a degree as the calcium salts.The difference may depend upon the fact t h a t the magnesiumsalts are in general more readily soluble, so that their excretionis comparatively easy. Fur thermore the " triple* phosphate "Mg(NH4)PO4, the insoluble magnesium salt, does oa t appearin large quantit ies in the faeces except in abnormal conditions,

6. T U B ADMINISTRATION OF A L K A L I E S AS A

PREVENTIVE O F ACIDOSLS,

Calcium carbonate, therefore, acts in the animal body asa free base in this respect, tha t it is competent to ncutralineacids, and thus to reduce acidosis. Obviously, all inorganicbases in the free state can act in the same way, provided tha tthey can be absorbed by the organism in a soluble form*The free basrs, however, have, like the frcie acids, and vvvnmore than these, the disagreeable quali ty of twing corrosive.They dissolve organic matter, and can therefore not ht\ tulir-atcd b y the organism except in extreme dilution. The.alkaline carbonates, though thrir commvv influences in lesspowerful, arc nevertheless not free from this influence, when#a.scalcium carbonate is, an such, insoluble and innrrumm.Large doses of this salt can, in fact, be given throughout along period without any injurious consequences, differing inthis respect from the othcur carbonates

I t need hardly be said tha t the soluble hu%en can also beadministered in the form of their combinations with t he

88 VITAMINS

organic acids ; these salts have little or no corrosive influence,and can be used to increase the quantity of bases in theorganism. The lactates and the citrates are chiefly employedfor this purpose, having a less disagreeable taste than theacetates and the formates. Thanks to the vigorous propa-ganda of Oskar Loew, in human medicine calcium lactatehas had considerable vogue. This salt is especially usefulwhen the patient needing calcium is suffering from gastricdisorder attended by a deficiency of hydrochloric acid inthe gastric secretion, for calcium lactate does not reduce theacidity of the gastric juice. In experiments on animals,bases are usually administered as lactates or citrates, whetherthe aim be to counteract the effects of a diet unduly rich inacids, or to provide supplementary bases in food otherwiseinadequate in this respect.

For brief periods, the occurrence of acidosis in consequenceof a diet rich in acids can be prevented by the administrationof one base and one only ; but it must be carefully noted thatany such one-sided dosage will prove unwholesome in thelong run. The body needs a number of bases, and not onemerely; if satisfactory results are to be secured, the foodmust contain all the ingredients necessary for proper nutritionand the maintenance of life. The most bountiful administra-tion of one single base will not suffice, for in inorganic meta-bolism the individual substances are mutually dependent.Clinical experience teaches that sodium bicarbonate inquantities amounting to hundreds of grammes will not preventthe death of a diabetic from coma, that is to say from acidpoisoning. On the other hand, in such cases, when the useof sodium bicarbonate was no longer helpful, I have foundthat incipient diabetic coma can be arrested by the administra-tion of a mixture of all the necessary inorganic bases.

7. FORMS OF COMBINATION OF INORGANIC SUBSTANCES;

THEIR MODE OF ACTION.

This partly explains Osborne's experience that protein-jfree milk is by far the best provider of bases. I t must ofcourse be remembered that in protein-free milk the inorganicconstituents are supplied in a form in which they can actmost effectively.

IMPORTANCE OF INORGANIC SUBSTANCES 89

In artificial mixtures of nutr i t ive salts, those salts areall present in a readily ionisable form. As such, however,they play the part of foreign bodies in the organism, for tht*yspeedily increase the osmotic pressure to an iatolerable degree.Hence they are eliminated as rapidly as possible. Manyinorganic salts begin to make their appearance in the urinewithin ten minutes of their administration "by mouth, and,speaking generally, the whole dose will have been excreted^within twenty-four hours. The excretion, however, is noteffected strictly proportionally to the concentration of thesubstance in the blood, but occurs irregularly, so that theexcretion of the last traces may often he deferral for a longtime. I have found that in the casts of calcium and phos-phorus compounds the excretion may not ho completed untilafter the lapse of five or six days . But as far as a strongconcentration in the organism is concerned, this lasts onlyfor a brief space of time, and the period of efficacy of nuchsubstances in the body is therefore strictly limited. The;reaction of the urine gives the best proof of this. Whenant acid-rich diet is being taken, and we aim a t neutralisingthe excess of acid b y administering; inorganic bases in theform of salts, the use of litmus paper will show that tlus urinespeedily acquires an alkaline reaction. During the night,however, the period when the great cleaning up of the organinmafter the clay's exertions takes place, the amount of availablebases is greatly reduced owing to the rapid excretion of theionised salts, the result being tha t the morning urines (whichcontains the products of tissue change during- tin night) himagain become acid, and is rich in uric acid although its JW>W«Tof holding uric acid in solution is smal l In other words,when the requisite bases are supplied in the form of inorganicsalts, they are excreted so rapidly that the organism mifiemfrom alkaline impoverishment at the t ime when its need itiralkalies is the greatest.

Conditions are very different in the case of na tura l nutrient*.Here the inorganic bases are, t o some extent at least, presentin masked forms, in stable organic combination, nnd theirpresence can in many instances not be detected until niterthe destruction of the organic combination. To some axtent,compounds of this character are even able to resist tbe dh*

9o VITAMINS

integrating effects of digestion, as I have myself proved inthe case of milk.69,70 In this form, the bases do not irritatethe animal organism in any way, and they can be retainedby the body for a considerable period, until the bases arerestored to an ionisable condition by the break-up of theorganic combinations. If, therefore, the organism be providedwith an abundance of bases by supplying it with a foodnaturally rich in bases, ere long the morning urine will befound to have an alkaline reaction. In such cases the uric-acid content of the urine will tend towards a minimum charac-teristic of the particular diet ; and at the same time thecapacity for excreting uric acid, that is to say the competenceof the urine to dissolve uric acid, will rise to a maximum.Thus whereas the effect of the bases in artificial mixtures ofinorganic salts is restricted to a period of an hour or twoafter their ingestion, the bases in the natural nutritive saltsremain effective over long periods, and are always on hand

Jwhen the organism needs them. In my own experiments,^1 have found that the water in which potatoes, greens, etc.,have been boiled, or protein-free milk, is speedy and effective.

These considerations perhaps explain how it is that theill effects of acidosis, and above all emaciation on the onehand or oedema on the other, can be remedied, temporarilyat least, by the abundant supply of protein in the form ofmeat. From the great excess of protein, large quantities ofammonia are formed, and by this the simultaneously introducedacid-formers can be neutralised and rendered fit for excretion.The inorganic bases in the meat, which to some extent arepresent in more or less complex combinations, are therebyreinforced, and a respite is secured, for these inorganic basesare not excreted very swiftly, and remain available to someextent for use where they may be urgently needed. (CiEmmet 346.)

8. MUTUAL INTERDEPENDENCE OF THE INORGANIC

SUBSTANCES.

If in experiments concerning complettins the investigatorwishes to use mixtures of simple salts, he must always bearin mind that in long-continued experiments the effect ofthese mixtures does not depend solely upon the excess of

IMPORTANCE OF INORGANIC SUBSTANCES 91

bases supplied. Tlie law of the minimum is hern in fulloperation ; the final upshot will be determined hy the* sub-stance t ha t is present in the relatively smallest proport ions.I t is hardly possible to l>e too emphatic about th i s ina tUr .We have to think, net merely of a minimal requirement oj inorganicsubstances in general, hut also of a minimal requirement ojtack inorganic substance in particular. (Cf Clsborne andMendel,"4?* il% »37 McCollum and Sim mantis ,^* loiG J*arr,IO55Hess,101** Kul£,M <jrablcy97i.)

I n this connexion it is necessary (o refer to a considerationwhich all investigators have hitherto overlooked. I t doesnot follow tha t because a mixture of salts has proved a usefulsupplement to a particular nutrient or to a par t icular formof diet, that it is an infallible dietetic supplement which willdo equally Rood service in the case of any uric I every diet.If, for instance, a second nutrient contains a larger excess ofacids than one which lias previously been given, the na tura lway of dealing with this supplementary excess will be h ygiving larger doses of the mixture of salts, lint if t h e undueacidity be a one-sided affair, dependent let us suppose uponan excess of phosphoric acid in the nutrient, an optimal effectcannot be secured by a mere increase in the amount of a gemra lmixture of salts. The phosphoric acid will need for its c*xcr<vtion by the intestine a preponderant percentage of thecalcium in the mixture of salts, and this will u n d u l y rc*<iur.&the quant i ty of calcium available for the other n r eds of theorganism. Furthermore, the rat io between t h e availablecalcium and the magnesium or the alkalies will thereby bereduced to the disadvantage of the calcium. In surh a cas<»,therefore, we must not merely increase the dosage of th« aggre-gate mixture of salts, but must take these peculiar condit ionsinto account by specially increasing the dosage of calcium.

In other cases, the quant i ty of sulphur may be unfavourablyaffected in one way or another ; there may he too littkj srxliurn,iron, or manganosc; or there may be too m u c h chlor ine ;a n d so on. In a word, generalisation is especially unsafewhen v/e are dealing with this mat te r of inorganic: metabolism.A decision as to the composition of the supplementary mixtureof salts must always he based upon an accurate analysis oj theconstituents cf the diet. To this mat ter we shall return*

92 VITAMINS

v/ 9. T H E UTILISATION OF CALCIUM I N VARIOUS F O R M S C

ADMINISTRATION.

A special problem is intimately connected with t h e fgoing—the extent to which the inorganic constituents ofvarious nutrients can be utilised. As far as the basesconcerned, a detailed study of the question has been ironly in the case of calcium. McClugage and Mendereport that in dogs the calcium in milk is be t te r u t i lthan the calcium in carrots or spinach. Rose I0I9> io83 coto the same conclusion as regards human beings, finding tthe utilisation of calcium in carrots is much less efficient tlthe utilisation of calcium in milk. A critical s tudy of titpapers leaves a different impression on my own mind ,far as the dog is concerned, we must remember t h a t 1animal, being a carnivore, is better adapted to digest aniifoods rich in protein than vegetable foods ; the dog's in tes tis too short far a vegetable diet. In such experiments, d<should be habituated to a vegetable diet before t h e specenquiry begins. Next it must be noted that if t h e dognot habituated to a diet of spinach or carrots, d iarrhoea \ensue, involving great losses of calcium; this is especiaobvious when we recall that to supply the amount of Ihcontained in a very small quantity of milk, large amouiof spinach or carrots will be requisite. The mistake h a s bemade that is unfortunately so often made by those who astudying the physiology of nutrition, of regarding " digestioras synonymous with " utilisation.'' I n the process of n u t r i t iwe must distinguish three stages which are to a consideratextent independent one of another, napaely digestion,-absertjiQn, and assimilpjien. Only when assimilation is unsatifactory, are we entitled to speak of a substance as imperfectutilisable. If McClugage and Mendel h a d told us t h a t spina<and carrots were not satisfactory as sources of calcium f<dogs, they^ would have been within the mark, b u t theresearches give us no information as to the degree to whicthe calcium is utilisable. A nutrient may be badly bor iby an animal whose digestive system is ill-adapted to de,with it, but we are not entitled to infer that such por t io iof the nutrient as are digested are badly assimilated.

IMPORTANCE OF INORGANIC SUBSTANCES 93

Rose, keeping four healthy human beings under observation,ascertained the calcium balance when a diet was being takencompetent to supply appraximately the minimal requirementof calcium. I n two of the cases the experiment lasted afor tn ight ; in the other two, three weeks. In two instancesthere was a preliminary period in which the calcium neededwas provided chiefly from milk, whereas in the main experi-ment the calcium was supplied in a daily ration of 40a grammesof boiled carrots. The experiment is so typical of t h e short-sighted way in which inferences are drawn from experimentson nutri t ion tha t I cannot refrain from a brief examinationof t h^ results.

Person,

E. D. B,E. D. B.K. S. E.R. S. E,£. H.E. W.

Diet.

MilkCarrotsMilkCarrotsCarrotsCarrots

Calciumsupplied inCtAmm<s$t

0*383

0*2:97

IVremtM* ntCalcium trutn

Carrots.

0$50

84si

JVrmttaRnIitrmttwit <*t

Drfldt.

4 16•H7

+ 44*7

From this i t appears tha t in E. I ) . B. the calcium fromcarrots was qui te as efficiently utilised as the calcium frommilk, whereas in R. S. E. a deficit occurred during t h e carrotdiet. But the retention of calcium during the milk diet was5° % greater in R. S, E, than in JL I), R Thin immediatelysuggests t ha t what occurred in R, S* E, dur ing the milkperiod was not an assimilation of calcium but a simple roten-t ion of calcium. Every investigator who has been engagedin researches on calcium metabolism must be aware; that thissubstance is not rapidly excreted, and tha t a quan t i t y ofcalcium introduced with the food is not fully dischargedfrom the body unti l a t least five or six days have elapsed. Insuch investigations, therefore, a s tandard diet mus t beselected, and must be given far a preliminary period duringwhich the utilisation of the substance under considerationhas been ascertained. Then follows the main period of theexperiment, during which the test substance is added to thes tanda id diet. In a final period, when the administrat ionof the test substance has been discontinued, t h e process oi

9 4 VITAMINS

its elimination is kept under observation. Thus only cansome safeguard be secured against surprises due to retardedexcretion. This simple measure of precaution was not t akenin Rose's experiments, and i t is therefore probable tha t t h ewell-marked positive balance during the milk period waspartly due to such a retardation of excretion, and tha t t h equantities of calcium that had previously been retained wereexcreted after the milk had been discontinued, tha t is to sayduring the carrot period, so that the balance was then falsifiedto the apparent detriment of the carrot calcium. We infer,therefore, that the experiments on E. D . B. and R. S. E . ,in which a comparison between a milk diet and a carrot d ie twas made, afford no justification for declaring t ha t there isa difference in the utilisation of the calcium from milk andcarrots respectively. I n the cases of E. H. and E . W. , therewas no initial period of milk diet, and therefore no directcomparison between milk and carrots is possible. A p a r tfrom this, the experiments show such remarkable irregularitiesthat we are entitled to challenge the accuracy of the results .

In E. H . the increment is only 4 %, whereas in E . W. i t is27 %, although the difference in the amount of lime given in.the two cases was only 14 %. A strict criticism of the experi-ments therefore leads us to infer tha t in two cases t heutilisation of the calcium of vegetable origin was as great a sor 70 % greater than the utilisation of the calcium in milk—>which is the very opposite of what Rose contends. Con-versely, in the other two instances, the utilisation was lessefiective in the case of the calcium of vegetable origin. W emay infer with some probability tha t the calcium in thesetwo nutrients has the same "biological value.

As a result of the observations of other medical practi t ionerswe are entitled to draw the general conclusion tha t t h e inorganicbases are always fully utilisable so Jong as they are administeredin such a form that they can be assimilated by the organism.

10. T H E EFFECT OF OXIDATION UPON THE BIOLOGICAL

VAXTJE OF THE ACID-FOHMERS.

Even when a precise analysis has informed u s concerningthe natiire and quantities of the inorganic const i tuents ofthe food, so that we are enlightened as to what supplementary

IMPORTANCE OF INORGANIC SUBSTANCES 95

inorganic nutrients may be required, our difficulties are byno means at an end. All tha t the analysis tells us is theaggregate amount of phosphorus, sulphur, etc. I t may,however, very well happen tha t in one case this or t ha t inor-ganic substance is present mainly in an oxidised (that is tosay in an inorganic form), and tha t in another case it is presentin the form of some complex organic compound. In thelatter event, it may sometimes be one of the components ofa readily oxidisable substance, and sometimes one of thecomponents of a substance difficult to oxidise. The bearingon the amount of the inorganic nutr ient tha t is requisite willvary iji each case. If, therefore, we wish to ascertain ananimal's requirement in respect of any inorganic substance,preliminary researches must be made to ascertain whether(when the diet is otherwise adequate) the selected method ofadministering the inorganic nutrient be a suitable one. Notuntil we know this, can we proceed with the main subjectof research. The problems are further complicated becausethe requirement of inorganic nutrients varies in differentspecies of animals, and also because the requirement is exten-sively modified by the state of the animal as regards growthand other physiological conditions, such as procreation,?menstruation, gestation, lactation, etc. Above all in the case;of phosphorus and sulphur we have to reckon with, not merelythe absolute quantity in the food, but also the nature of thecompound in which these elements are supplied. We knowvery little concerning the modes of combination of sulphur,and contributions to our knowledge in this respect would bemost welcome. Apart from the purely inorganic compoundsof sulphur, we know this element in the organism only in theform of cystein or its " anhydride " cystin, although therecan be no doubt that quite a number of sulphur compoundsare represented in the " neutral sulphur " of the urine. Froma private communication I learn tha t Hopkins has recentlysucceeded in isolating a number of new sulphur-containingorganic substances. If this is confirmed, the importance of un-oxidised and organically combined sulphur will be yet furtherenhanced, but nothing has as yet been published on the subject.

I have already mentioned tha t the peculiar importanceof the two sulphides to the animal organism is made manifest

9 6 VITAMINS

by the consideration that cystin is a vitally essential substanceiwhich cannot be synthetised within the animal body. I n'one of their papers, Osborne and Mendel maintain 7 9 t h a tthe inorganic constituents of the food need only be suppliedin inorganic form. But this conflicts with other reports bythe same investigators, who (as we learned in the second chapterof the present work) have repeatedly noted that growth, andeven the mere maintenance of weight, are impossible unlesscystin be supplied ready made. Hirschstein *59 states as theresult of experimental work that a number of nutri t ive andmetabolic disorders can at least be benefited by the supplyof cystin when this substance has been deficient in the food.Florence,1^6 too, emphasises the same fact, but supports hiscontention only by reasoning, and not by experimental data .

Though there is unanimity as concerns the need for thepresence in the food of sulphur in organic combination, thisis far from being the case as regards phosphorus. There isnothing to surprise us in the notion that the organism's needsfor inorganic phosphorus in the oxidised form can be suppliedout of phosphorus in organic combination (cf. Lipschiite,xx9Heubner,46° and Grosser288), seeing tha t during the disintegra-tion of organic substances within the organism the phosphorusundergoes combustion to form phosphoric acid.

Moreover, every breeder of animals know that the growingorganism can utilise simple inorganic phosphorus for thebuilding up of its osseous system ; and by Tereg and Arnold *the fact has been experimentally proved in the case of growingdogs. Recently, Schloss and Herbst, in an extensive seriesof researches, have shown that the statement is equally trueof children.

We face a different problem when we ask whether theanimal organism is also competent to build up organic phos-phorus compounds out of inorganic. Here most physiologistsmake the mistake of failing to distinguish between salt-likeor ester-like compounds (the so-called mixed-organic com-pounds) and compounds into which the phosphorus M sentered as ,a constituent part, of an prganic complex. Yet thechemical distinction is vital. In the first case we have merelyto do with the formation of an oxygen (ester) or amino-com-pound (salt)—substances in which the oxides of the phosphorus

IMPORTANCE OF INORGANIC SUBSTANCES 97

still retain a thoroughly inorganic character. This is manifestinasmuch as simple hydrolysis or double decomposition sufficesto liberate the inorganic component, so tha t its presence canimmediately be detected by analysis. We have, indeed, asuperfluity of proofs tha t such a combination can readilybe effected within the animal organism through the simplesplitting off of water or ammonia.

From these organic phosphates which are easily formedand easily destroyed in the organism, from these salt-likecompounds, we must distinguish as a mat ter of principle thesubstances in which the phosphorus exists in an unoxidisedor imperfectly oxidised form as a constituent of a purelyorganic complex, this being the form in which (in part , a tleast) the element is met with in the nucleoproteins. Forthe building up of such compounds, the phosphates as foundin inorganic nature must first be reduced, t ha t is to sayhydrogenised; and in such compounds the phosphorus subse-quently enters into so intimate a form of combination, tha tthe presence of the element can only be detected after apreliminary destruction of the organic complex by oxidation-So far as the more highly organised animals, a t any rate, areconcerned, we do not know a single instance of such a genuinereduction of phosphorus, and the incompetence of the animalorganism to achieve this reaction is the probable explanation ofthe inability of the higher animals to synthetise carbon chains.

Consequently, when Fingerling X99 found that , on a dietvery poor in organically combined phosphorus, hens continuedto lay regularly and to produce eggs containing a normalquantity of lecithin, he had merely discovered a fresh demon-stration of the familiar fact t h a t the animal body can buildup phosphorus into compounds of the ester series; but theexperiment throws no light on the possibility of a synthesisof genuinely organic phosphorus compounds.

Innumerable investigators have studied the problem, andalmost all of them have come to the conclusion tha t no suchsynthesis can be effected within the animal body. Againstsome of the earlier experiments, those of Steinitz,*7 Zadik,*9Leipziger,3° Ehrlich,3* and others, it is possible to lodge theobjection that these experimentalists did not succeed inproviding a diet free from organic phosphorus, or to complain

7

9 8 VITAMINS

that the duration of the experiments was too short. Thenegative issue of their researches has, therefore, n o demonstra-tive force. In other instances, as in the experiments ofGregersen/43 the duration was ridiculously brief, no a t temptwas made to avoid errors due to delayed excretion, and noexamination of the excreta was continued after t h e close of themain period of the experiment. The same criticisms applyto the experiment made by Hols t i I I 6 upon his own person.The positive results secured by Gregersen and Hols t i may,therefore, be interpreted as simply due to errors of experiment.

Only four decisive series of observations bear ing on thismatter have been recorded. Pa ton 3* has shown that whensalmon are on the way to the spawning-ground, and whenduring this period the testicles or ovaries undergo a n enormousenlargement, the phosphorus content of the ripe reproductiveorgans increases just as much as the phosphorus content ofthe muscles diminishes. Now the muscles contain a mixed-

* organic phosphorus compound, whereas in the ovaries andthe sperm there are nucleoproteins, which must have beenbuilt up out of inorganic phosphorus. But the demonstrat iveforce of Paton's observation rests upbn the old assumptionthat salmon take no food while on their way up river.Putter 87 has, however, shown that this assumption is un-founded ; during their migration up river it i s true tha tsalmon are less inclined than usual to feed on o t h e r fish, bu tthey consume plankton, and this fact cuts the ground fromunder Paton's reasoning.

McCollum95 experimented on growing rats w i t h a dietvery poor in phosphorus. The rats grew in a fairly normalfashion, but they lost weight, so that McCollum's inferencethat the rats did not need any organic phosphorus for thepurposes of their growth seems a trifle hasty.

Hart, McCollum, and Fuller 86 experimented on pigs witha diet containing very little organic phosphorus. T h e animalsgrew, but they suffered in the same way as t h e rats inMcCollum's experiments. When the pigs were killed, theosseous system was found to be only about one-fifth as welldeveloped as it would have been on a normal d ie t . Since,moreover, the experiments were not continued unti l theanimals were old enough to reproduce their kind, t h e y lackcogency.

IMPORTANCE OF INORGANIC SUBSTANCES 99

All tha t remain, then, are the experiments of Osljornc,Mendel, Ferry, and Wakeman 7*9 on rats . B u t in thifi casethe diot was not free from organically combined phosphorus,and since the work of other investigators i r9. *99> &* has shownbeyond dispute that the need for organic phosphorus is verysmall in comparison with the need for inorganic phosphorus,these experiments, too, lack demonstrative force. We mustremember that even edestin, the protein which is most easilyprepared in a pure form, is never free from phosphorus—-although some of the American investigators contend tha tit is. I have been led by the publication of the Americanresearches to examine a number of the eclestins of commerce,and have found them all to contain phosphorus, sometimes inconsiderable amounts . The firm of Merck manufactured toa special order a sample of edestin of the utmost puri ty. Tliiscontained o-0681 % of phosphorus (estimated as P3O3). Onfurther enquiry, t he manufacturers said they could not supplyanything purer. My own a t t empts to produce an edestinfree from phosphorus were equally fruitless. If a pure crystal-Usable protein contains so large a. percentage of phosphorus,we are certainly entitled to assume tha t the commoner sortsof protein ordinarily employed in experiments on nutr i t ionmust contain even larger amounts of organic phosphorus.Although is so many instances we are assured that the experi-mental diet was free or almost free from organic phosphorus,there is adequate ground for believing tha t the assertionswere based upon a defective analytical technique. Or, indited,the experimentalist may have accepted the manufacturer 'sguarantees at their face value,

Elaborate experiments made on dogs b y Rogoainski I10

and Durlach aB7 gave negative results. Hare, however,deficiency of complettins and bases may have b u m acontributory cause,

All our extant experience would seem to point to theconclusion that the amount of organic phosphorus requiredby the organism is very small, t u t tha t the higher animalsare incompetent to synthetise such genuinely organic phos-phorus compounds as they actually want . In experimentsconcerning complettins it is therefore essential to see t h a tthe bodily need for phosphorus in organic combination isduly satisfied.

CHAPTER FOUR

BERIBERI AND OTHER FORMS OFPOLYNEURITIS

i . ETIOLOGY.

BERIBERI used to be regarded as one of the infective diseases,and as late as 1911 leading Japanese authorities made merryover the learned Europeans who took another view, whooverlooked obvious facts, and fancied that in distant Europethey could discover something precise about beriberi whichwas hidden from Japanese scientists on the spot.x33> 136 Nodoubt there was a good deal to be said for the infectiveetiology. For instance, especial stress was laid upon thefact tha t beriberi, or kakke as the Japanese name it, wasformerly quite unknown in the interior of Japan, and thatas the railway system of the country developed the diseaserapidly spread into the interior along the new routes ofcommunication. Then, as earlier, the staple diet -»of theJapanese peasants was rice. If the Europeans were right inthinking rice to be a causative factor, its action, said theJapanese, could at most be indirect. Perhaps the rice was aculture medium for the infective agent. The infective theoryseemed all the more probable when it appeared during thelatter half of the Russo-Japanese war that the substitution ofbarley meal for rice did not prevent the spread of beriberi.Even to-day, quite a number of persons still cling to the infec-tive theory, and during the late war evidence was broughtforward which seemed to support such an etiology. Forexample, Sprawson »3* was of opinion that the beriberi fromwhich the British troops suffered in Mesopotamia must havehad a twofold causation. Among the Indian sailors a t themouth of the Shat-el-Arab, the disease was a true avitaminosis,for these sailors were strict Mohammedans who would not

FORMS OF P O L Y N E U R I T I S 101

touch European food, and lived entirely on polished rice.The Goanese, who were working in the same place, bu t whoate European food, remained healthy. Among the Chinesecoolies employed in Mesopotamia, beriberi had broken outduring their transport to the country, so tha t this was likewisea true ayitaminosis. There was, however, no improvementin the health of the Chinese coolies when they were put uponEuropean d ie t ; and there now ensued among the Europeantroops, who ate abundant meat in the customary fashion,repeated epidemics of beriberi, some of them very severe.Sprawson was of opinion that the epidemiology of the diseasecould (jnly be explained on the theory tha t among those wholived on European food it was spread by infection, seeing tha tthe generous meat rations must have contained sufficientvitamin. The theory received official endorsement, for inthe discussion on the avitaminoses,1066 even the noted Britishscientist Hopkins described infection as* not altogetherimprobable in such cases. For similar reasons, Marchoux "55came to the same conclusion regarding the causation of theepidemic among the Annamese soldiers in AngoulSme.

In both these instances, however, the fundamentalassumption that the diet had contained sufficient vitaminwas cQntested by other authorities. Willcox,I0*5, Io66 Humeand Chick,1066 and also Wallis,1066 pointed out tha t the beriberiepidemics in Mesopotamia only occurred when difficulties inthe supply of fresh meat had made i t necessary to feed thetroops on corned beef, and tha t the bread in the soldiers'rations was made from the finest white flour and was thereforevery poor in vitamin. In the corned beef, the vitamin hadbeen destroyed during the process of sterilisation. (The laststatement may be correct, but it is interesting to note howamong the Entente States as well as among the CentralEuropean States the profit-hunting of the owners of the canningfactories entailed the death of countless human beings. UdoKliinder J3*4 has shown that , during the war, in the preparationof corned beef in America, the water of the first boiling,which is known to contain an abundance of vitamins, wasseparated from the meat and made into mea t extract. I nthe weakly acid medium of the fresh meat i t is quite probablethat , bu t for this, a sufficiency of vitamins would have resisted

102 VITAMINS

the process of sterilisation.) Regarding the epidemic amongthe Chinese coolies in France, Leggate I01* reports that thestaple diet consisted of polished rice, and though a meat rationwas given once or twice a week, the meat was tinned.

So many instances were known in which intoxicationcould be excluded, that it was necessary to look for othercauses. The most notable fact in the epidemiology of beriberiwas that when the disease occurred in rice-eaters it was onlyin those who consumed fully hulled and polished r ice ; andthat partially hulled rice, still invested with the pericarp orsilver-skin, was actually able to cure the disease. A firstglance at the composition of polished rice seemed, therefore,to those medical practitioners who continued to believe inVoit's dogmas concerning nutrition, to support the theorythat the cause of beriberi was an insufficiency of protein andfat. The observations of Chamberlain and Vedder J56 werein harmony with this, for they found that persons fed on aninadequate supply of unhulled rice, or suffering from actualfamine, developed symptoms resembling those of beriberi,and tha t in this disorder just as in true beriberi, the firstsymptom was a loss of weight amounting to at least 21 %.Eijkman 5l6 likewise found that polyneuritis occurred in fowlswhose diet was quite inadequate, and that this polyneuritis,too, could be cured by dosage with vitamin. Segawa,3*3however, regarded the malnutrition as no more than asecondary symptom dependent upon the gradual developmentof a repulsion for the monotonous diet.369 This theoryconflicts with the universally known fact that the body-weightbegins to decline directly the subject is put upon the patho-genic diet, long before any repulsion arises. As long ago as1902, Hulshof£-Pol 38 drew attention to this initial loss ofweight, and his data have been confirmed by all subsequentobservers.

Nearly twenty years earlier, Urbeanu8 had shown thatin dietetic polyneuritis the phosphorus and potassium balancein experimental animals became negative from the very outset.Chamberlain, Bloombergh, and Kilbourne X45 pointed out thatall the nutrients known to cause beriberi axe poor in phosphorusand potassium. Vedder 314 confirmed this, but was of opiniontha t the deficiency of these substances did not suffice to

FORMS OF POLYNEURITIS 103

explain outbreaks of the disease. In 1904, Durham 44 hadshown that the nitrogenous balance became strongly negativewith the appearance of the first symptoms of the disease.These points were not fully cleared up until the comprehensiveresearches of Schaumann I23» 36x had shown tha t directlythe experimental diet was begun, the balance of nitrogen,total ash, and (above all) calcium and phosphorus, becamemarkedly negative, and grew continually more unfavourableas the disease progressed. Observations made by Aron andHocson,I49 and by Breaudat,*72 that the addition of meat tothe diet did not cure beriberi, ran counter to the theory tha tthe disease is due to malnutrition in the ordinary senseof the term. According to Tasawa,33* a peculiarly typicalpolyneuritis ensues upon a diet in which polished rice issupplemented by white of egg or thoroughly boiled m e a t ;and Lovelace262 has seen a number of cases of beriberi inwhich the supply of protein in the food had been abundanteven in accordance with the older dietetic standards. Edie,Evans, Moore, Simpson, and Webster2 2 0 found, indeed, tha tthe addition of casein somewhat retarded the onset of thedisease; but the most plausible interpretation here is thatthe casein of commerce used by the experimenters was notperfectly free from vitamin.

In one respect there is something to be said in favour ofthe opinion of those who have held tha t the inadequacy ofrice protein is responsible for the occurrence of beriberi, forBarrIO55 has drawn attention to the fact tha t experimentalpolyneuritis closely resembles the diseases tha t result fromfeeding with an inadequate protein—for instance, one charac-terised by a lack of tryptophan. This, however, can onlybe an accessory factor, for were it the efficient cause theaddition of protein to the diet would prevent the disease,and we have learned that it fails to do so.

Br6audat 3C72 found also that the addition of fat or carbo-hydrates was ineffective. Indeed, in monkeys sufferingfrom beriberi, the addition of butter to the diet hastens theend.IO56 In part this remarkable result may be explainedby the supposition that the provision of additional combustiblematerial imposes upon the body an additional task with which,in its weakened state, it is unable to cope, so tha t the acidosis

106 VITAMINS

induce in fowls a polyneuritis which closely resembles humanberiberi. In this connexion it may be of interest to notethat polyneuritis gallinarum has recently occurred on a largescale, as an outcome of wartime feeding, in Holland amongordinary domesticated fowls.975 This proves that the experi-mental polyneuritis previously observed was not simply anartificial product of laboratory conditions, but a nutritivedisorder perfectly analogous to beriberi. I t has now, therefore,become possible to study in animals the complicated problemsconcerning this enigmatic disease more intimately and morespeedily than could be done in human beings in hospital.

Hoist and Frolich 6a> 63, *4,65,100, 105, 107,186 h a d ^Jreadynoted that not only polished rice, but most other cerealsfrom which the bran has been very thoroughly removed andwhich have been finely ground and sifted, induce scurvy inpigeons and barndoor fowls. When unhulled, these cerealsare harmless to such birds, but bread made from fine flouris extremely injurious. The same observers discovered thatraw meat does indeed cause general disorders in fowls, butthat the birds become affected with polyneuritis only whenthe meat had been boiled for a long time, or superheated( u o ° to 1200 C) . In l ike manner, potatoes that had beenlong boiled induced polyneuritis in fowls. Hart , Halpin,and McCoUurn6l* also showed that unhulled cereals wereharmless to fowls, provided that calcium carbonate wasadded to the food in order to prevent the incidence of otherdiseases than beriberi. According to Weill and Mouriquand,627hulled maize and sterilised maize both cause polyneuritis,whereas the hulls of raw maize have an antineuritic influence,and, according to Clementi,5*9 fowls which have been affectedwith polyneuritis by being fed on rice can be cured by givingthem wholemeal from maize. According to Schaumann,36itoo, the whole maize is harmless to pigeons.

Nevertheless, cases of beriberi have been reported in whichthe pathogenic agent was unquestionably unhulled rice, andnot polished rice. IO77, "55, II8* The most reasonable explana-tion of these instances is to suppose that in such cases therice had been kept too long in store.

I t has long been known that gi;een peas and fresh beajisare rich in vitamins. This is especially true of the katjang-idjo

FORMS OF POLYNEURITIS 107

bean (Phaseolus radiatus), renowned as a remedy for "beriberi.As early as 1902, Hulshoff-Pol 3* prepared an extract ofkatjang-idjo which was successful in curing beriberi. Mosz-kowski X74 expressly declares t ha t when an exclusive diet ofpolished rice is producing beriberi, the occurrence of tliedisease can be prevented by the addition of comparativelysmall quantities of this bean to the daily ration. Schaumann 3^confirms the statement that katjang-idjo has both a prophy-lactic and a curative action in beriberi ; bu t adds tha t theremedial influence of the bean declines as it gets older, andthat beans which have been stared for five years are quiteineffective. This accords with the report of Weill, Mouriquaud,and Michel,496 that sterilised meat will induce polyneuritisin cats marc rapidly in proportion to the time the meat hasleen stored. The same observers found that raw frozenmeat or salt moat was well borne by cats if fresh, whereas-when it has been long kept it is known to be free from vitaminsand to have a pathogenic influence.

I rnxist repeat that in the case of seeds, too, the methodof preparation is of much importance. Osborne and Mendel 493found tha t there was abundant vitamin in cotton seed, t u tItommcl and Vedder4fa report that fine cottonseed meal,as an exclusive diet or as an extensive supplement to hay,induces polyncuritis in cattle. In like manner, pigs fed onhulled rice, cottonseed meal, or a mixture of maize mealand cottonseed meal, speedily became affected with poly-neuritis. In conformity with the observations of Hoist andJrolich, Little i6t reports the occurrence of "beriberi in St.Anthony (Newfoundland) and Labrador in persons nourishedalmost exclusively on fine wheaten flour. I n the pig, too,according to Hart , Miller, and McCollurn,5*5 large quantitiesof fine wheaten flour give rise to polyneuritis.

The question is greatly complicated by the circumstancetha t the same nutrient has very different effects in differentspecies of animals. We have seen that maize is harmless tofowls and pigeons ; and according to Hoist and F r 6 l i c h m

xats remain healthy on a maize diet,—an observation confirmedfcy Schaumann. Conversely, Schaumann's experiments showtha t maize induces rnarlfced polyneuritis in r abb i t s ; Hoistand FrQlich, and also Schauraann, have found tha t it causes

108 VITAMINS

scurvy in guineapigs; whilst Weiser *58 states that pigs fedon maize perish from general malnutrition. Again, accordingto Har t , Halpin, and McCollum,612 fowls fed on wheat remainhealthy, whereas pigs and rats develop polyneuritis on thisd ie t ; and Hoist and Frolich inform us 65 that guineapigsfed on wheat suffer from scurvy.

The varying reaction of different species of animals to anidentical diet is still a complete enigma, and in my opinioninsufficient attention has been paid to the matter. Speakinggenerally i t would seem that graminivorous birds thrive onwhole grains, bu t suffer from polyneuritis when the grainis hulled. In mammals, on the other hand, grain feedingmay cause polyneuritis in certain circumstances, especiallyin rodents (except for the omnivorous rat), which are highlysusceptible to acidosis. In many mammals, however, a graindiet induces scurvy instead of polyneuritis ; while some animalsperish from general malnutrition owing to the inadequatesupply of inorganic nutrients in the grain. When grain hasbeen very thoroughly hulled, almost all animals, human beingsincluded, become affected with polyneuritis. Are thesevariations due to varying requirements in respect of v i tamin;or are the polyneuritic disorders due to the absence of variousvitamins which act differently in different species of animals,or are essential to different species in a varying degree ?

Hoist and Frolich (op. cit.), experimenting on guineapigs,found tha t these animals on an exclusive cereal diet invariablysuccumbed in from fifteen to forty-six days. In sixty-fivefatal cases, sixty-three were well-marked instances of scurvy,and only two were instances of polyneuritis. I t is true thata large number of the animals dying of scurvy were found onpost-mortem examination to have degenerative changes inthe finer ramifications of the peripheral nerves, but there hadbeen no paralytic symptoms. Considering this observationin the light of'what has previously been said, its interpretationbecomes easier when we recall tha t rodents are extremelysensitive to acidosis, which in these animals always leads tohaemorrhages, and frequently to the occurrence of oedema.If their food be characterised by a lack both of vitamin and ofthe antiscorbutic complettin, the effect of the latter deficiencywill be reinforced by the acidotic influence of the food, so

FORMS OF POLYNEURITIS 109

tha t scurvy will develop unless there be some special predis-position to nervous disease, a predisposition either congenitalor acquired. I t is in these exceptional instances of predisposi-tion t ha t polyneuritis develops. But the fact tha t in suchcases, also, the bones were found to be " as thin as paper,"shows that scurvy or acidosis existed as a complication.

We have already learned tha t beriberi in human beingsand polyneuritis in other animals are not solely associatedwith an exclusive rice diet, but may occur when various othernutrients are given. Even when these pathogenic nutrientsare given in conjunction, and even when they are given (ofcourse in preponderant quantities) in association with nutrientstha t have a curative effect on polyneuritis, polyneuritis willensue, as happened in the case of the British troops inMesopotamia, and as was observed by Dufouger£ "44 in FrenchGuiana. Lovelace262 reports a case of beriberi observed byhimself in which the patient had been taking a mixed diet.Dickenson,4*6 and also Smith and Hastings,286 noted theoccurrence of this disease in persons taking an extremelyvaried diet which seemed to comply with all the hithertoaccepted essentials of an adequate nutrition. " Ship beri-beri," which also arises in persons taking a mixed diet, cannotbe considered here, since nervous symptoms are entirelylacking in this form of the disease. The whole clinical pictureof ship beriberi assimilates it rather to malnutritional oedema,and we shall return to the matter in that connexion.

When beriberi occurs in persons taking a mixed diet, itwill be found: (a) that some of the important nutrientshave been subjected to a preserving process involving exposureto excessive or unduly prolonged h e a t ; or (6) tha t the cerealsin the diet have been subjected to too extensive a hullingprocess in the mil l ; or (c) tha t other important constituentsof the food have, in preparing them for the table, been boiledand tha t their vitamin content has passed into the cookingwater and been thrown away.

This account of the etiological importance of diet inrelation to the onset of beriberi may conclude with a referenceto the fact tha t both Cooper 269 and Vedder235 have foundtha t the use of alcohol does not appear to accelerate theonset of beriberi or to aggravate the course of the disease.

n o VITAMINS

2. ISOLATION OF VITAMIN.

The first attempt to isolate the antineuritic principle wasmade by Hulshoff-Pol 38, 68, 626 i n jgoz. Having prepared awatery extract of katjang-idjo beans, he added lead acetateto form a precipitate; the filtrate was then freed from leadby means of sulphuretted hydrogen ; "by subsequent evapora-tion at the ordinary temperature he secured an acid crystallinesubstance to which he gave the name of X acid. I t hadprophylactic virtues against "beriberi, and was a useful remedyin cases of that disease. McCollum and Sirnmonds 67° subse-quently isolated vitamin from haricot beans. Having extractedthese with 95 % alcohol, they got rid of the alcohol by evapora-tion, freed the residue from fat by treatment with ether,mixed it with dextrin, and precipitated the active principlein conjunction with the dextrin by means of absolute alcohol,These observers recorded as a remarkable peculiarity thatvitamin, which is ordinarily insoluble in acetone and benzene,can be extracted from the dried dextrin precipitate by theuse of acetone or benzene. This statement has not beenconfirmed by any other investigators.

I t was natural that other early attempts to isolate vitaminshould have teen made in the case of rice grains or the silver-skin of rice (rice polishings). In 1910, Fraser and Stanton Io8

reported that the active principle could be extracted from riceby means of alcohol. T i e next year, Funk *55 extracted thehulls of rice with alcohol, freed the solution from alcohol,dissolved the residue in dilute sulphuric acid, and thenprecipitated with phospho-tungstic acid ; the precipitate wastreated with "baryta water, and after the excess of baryta hadbeen removed by the addition of sulphuric acid, the filtratewas first purified with an excess of silver nitrate, and thenthe vitamin was precipitated as a double salt with silvernitrate by the use of baryta water. Prom this precipitateit was possible to extract a crystalline preparation, whichproved to be the nitrate of an organic base.

Subsequently the method" was much modified, but theessentials of the process remained unchanged—the crudevitamin was isolated by the precipitation of a sulphuric-acidsolution by means of an exactly adequate quantity of phospho-

FORMS OF P 0 1 Y N E U R I T I S i n

tungstic acid. Tsuzuki and Shimamura *s6 improved themethod. Having driven off the alcohol from the firstalcoholic extract, they removed the fat from the extract bj r

the use of ether. They were then content with decomposingthe phospho-tungstic-acid precipitate by means of baryta ,subsequently freeing the solution from bary ta b y t reatmentwith sulphuric acid, and then evaporating to a syrup. Bythis process they secured a thick syrup, acid in reaction, andrepresenting 0 . 3 % of the material originally extracted.They named the product aberi acid.

Schaurnann I 2 3 prepared his crude vi tamin in the firstinstance by extracting the silver-skins of rice (rice polishings)with albout ten times their weight of 96 % alcohol, drivingoff the alcohol by evaporation on a water-bath a t a moderatetemperature in a strong air-current, and removing the fatfrom the extract by the use of acetone. H e subsequentlysecured a purer product by the following process. Havingmade an extract with water, or bet ter still with dilute (o-z %)HC1, he treated the extract with 96 % alcohol, precipitatedthe filtrate with sublimate solution, and decomposed thisprecipitate. At a later date,36 1 he seems to have used 0-3 %HC1, but he states that extraction both with this and withalcohol is far from being successful. Hence we can under-stand the experience of Abderhalden and Lamp<3,289 whofound tha t extraction with alcohol did not notably impairthe curative virtues of rice bran.

Since Funk ' s method involves serious losses of the activeprinciple, Tsuzuki 3*° a t tempted to secure a crude preparationmore highly charged with vitamin. Having extracted with60 % alcohol, he evaporated to a syrup, which he saturatedwith ammonium sulphate until the proteins i t contained wereprecipitated; the filtrate was then freed as much as possiblefrom ammonium sulphate by the plentiful addition of alcohol ;the solution having been once more concentrated, was againprecipitated, this time with absolute alcohol, and the filtratethen concentrated by evaporation at a temperature of from6o° to 8o° C. to form a thick extract, brownish in colour. Tothis, Tsuzuki gave the name of antiberiberin. One kilogrammeof rice polishings yielded fifty grammes of antiberiberm.According to Schaumann 3** i t was almost entirely ineffective.

112 VITAMINS

Funk 273 endeavoured to purify his own crude vitamin byfractional crystallisation, thus securing two crystalline sub-stances. One of these was apparently nicotinic acid, and theother was a hitherto unknown nitrogenous body of highmolecular weight.

Before this, Tsuzuki, Shimamura, and Odake *10 had triedto obtain pure vitamin. The crude product resulting from thedecomposition of the phospho-tungstic-acid precipitate wasprecipitated with tannic acid and subsequently purified inthe form of a crystalline picrate. The substance thus obtained,known as oryzanin, was found by Drummond and Funk 39°to be quite ineffective.

The purest preparation hitherto secured is that made byHofmeister.11^ He treated rice polishings and rice husksthree times in succession with twice their bulk of 80 % alcoholin the cold, evaporated the extracts in vacuo, treated theresidue with hydrochloric acid even as strong as 3 %, andthen extracted the fatty matter with ether; the ether wasthen driven off in vacuo a t a low temperature; a thick syrupresulted, and this was purified by precipitation with 80 %alcohol. The filtrate, having been freed from alcohol in vacuo,was rendered slightly alkaline by the addition of sodiumcarbonate, and then precipitated with Kraut's potassium-bismuth iodide solution, care being taken to avoid thedevelopment of a strongly acid reaction. After five hours,the precipitate was removed by siphonage, decomposed bytrituration with silver carbonate, and the preparation wasthen promptly filtered. The filtrate was freed from silver byweak acidulation with hydrochloric acid, filtered once more,and evaporated in vacuo to near dryness. The residueconsolidated to form a faintly tinted, deliquescent mass witha radiating crystalline structure, and from 5 to 10 milligrammesof this sufficed in pigeons affected with polyneuritis to removethe paralytic and convulsive symptoms for from 8 to 10 days.By the gold hydrochloride method a pure substance could beprepared from this material, and to the purified preparationHofmeister gave the name of oridin (probably a dioxipiperidin),which however proved quite inefficacious. Hofmeister sup-poses tha t the efl&cacy of the crude material must dependupon the presence of small quantities of some constituent

FORMS OF POLYNEURITIS 113

which is lost during the process of purification (in that caseit must possess amazing potency). His alternative explana-tion is that the virtues of the crude material are destroyedby the purification.

Most investigators, however, in their at tempts at theisolation of vitamin, have recourse to yeast as a more readilyaccessible substance. As early as 1910, Schaumann "*secured an effective extract as follows. Having removed thefat from the yeast with ether, he extracted the residue with0 *2 % HC1, precipitated the extract with an abundance of96 % alcohol, repeated the solution and precipitation, andfinally, washed the precipitate on the filter with alcohol andether. Edie, Evans, Moore, Simpson, and Webster,2*0 havingextracted the fat from yeast with ether, treated the residuewith cold 96 % alcohol, and evaporated the alcoholic extractin an air current. The residue was then dissolved in 0-2 %HC1, purified by Funk's phospho-tungstic acid and silver-nitrate process, microscopic crystals amounting to 0-0038 %of the original yeast being ultimately secured. According toSchaumann,a3* if the process be arrested at the stage of decompo-sition of the phospho-tungstic-acid precipitate, an effectiveproduct is secured, but this contains considerable quantitiesof an impurity (perhaps cholin) which has a toxic action. Hehas therefore modified the process in this way.361 The filtrateafter precipitation of the baryta by sulphuric acid is evaporatedat a low temperature to a syrupy consistency, dried with silicain a vacuum exsiccator, finely powdered, and steeped twicein succession for forty-eight hours in absolute alcohol withthree drops of dilute sulphuric acid. On drying this alcoholicextract, he secured an active crystalline residue, which wasmanifestly a mixture. But in this case, as in tha t of therice vitamin, the activity of the preparation was destroyedin the purification of the separate components of the mixture.(Cf. Seidell M43.1484.) Funk, moreover, had earlier had thesame experience with yeast vitamin.273 He had isolated fromthe crude vitamin three crystalline substances, one of whichappeared to be nicotinic acid, whilst the other two werenitrogenous substances of high molecular weight.

Vedder and Williams,a84 in their experiments with ricebran, had found that the vitamin in the natural product must

a

H 4 VITAMINS

certainly -exist in a combined form, probably as the union ofa pyrimidin base with nucleinic acid, for the full efficacy ofthe extract was not developed until after hydrolysis. Theyfound, also, tha t Funk's method of preparation must beattended with great losses, for the original hydrolysate wasfrom twenty to twenty-five times more effective than thevitamin that could be extracted from it.

In the case of yeast, likewise, it appears that the fullefficacy is only developed after the autolysis of the yeast.As a rule, therefore, in subsequent investigations autolysedyeast has been used as raw material, and here again Williamsand Seidell56<> noted tha t the crystalline crude vitamin lostits efficacy completely during the process of recrystallisation.Abderhalden and Schaumann 8o3 subsequently prepared aneffective crude substance by simply precipitating the alcoholicextract of the hydrolysed yeast with acetone or mercuricchloride.

Sugiura776 reports an entirely new way of obtainingvitamin. He puts the dry yeast in a collodion bag, and fillsup with water, or better with 5 % sodium-chloride solution.The vitamin gradually makes its appearance as a crystallinepowder on the outer surface of the bag, and can be securedby merely brushing it off. I am not aware that this methodhas been checked by any other observer.

Osborne and Wakeman978 attempted to secure an activehighly concentrated crude vitamin in an extremely simplemanner. They gradually scattered dry yeast into boilingwater to which ten cubic centimetres of 1 % acetic acid hadbeen added. After two minutes* boiling, the whole wascentrifuged, and the yeast was washed once more with wateracidulated with acetic acid. The purified solution wasgradually diluted with alcohol, and precipitates were securedwith a content of 52 %, 79 %, and 90 % of alcohol by weightrespectively. The bulk of the vitamin was in the secondprecipitate, and represented about 6 % of the total dry matterin the yeast. Recently Frankel and Schwarz Jm haveattempted to secure vitamin in a pure state, but with theaid of a quite unsatisfactory control process. Having madean alcoholic extract of yeast, they removed the fatty matterwith ether and precipitated the residue with lead acetate*

FORMS OF POLYNEURITIS 115

The filtrate was freed from lead with sulphuric acid, andprecipitated with concentrated mercuric chloride solution,the precipitate being then treated once more with sulphuricacid. The filtrate from mercuric sulphate was freed fromsulphuric and hydrochloric acids with lead oxide and silvercarbonate, and then concentrated in vacuo. By degrees,there crystallised out a substance, which, however, provedinactive. The highly active mother solution was purifiedwith picrolonic acid, the filtrate was precipitated with asufficiency of phospho-tungstic acid, and the precipitatedecomposed with baryta water. The filtrate was freed frombaryta^ by the addition of 50 % sulphuric acid, refiltered,and concentrated in vacuo. The yield was 0*2 % of a veryactive syrup. Attempts to extract the free base from thisby treatment with amyl-alcohol after alkalinisation withbicarbonate, were fruitless.

A somewhat new method has been adopted by Myersand Voegtlm,IX44 who omitted the precipitation with phospho-tungstic acid. Dried yeast was powdered, and boiled repeat-edly in methyl alcohol containing 1 % of concentrated hydro-chloric acid, the alcohol was distilled off, the residue wasdissolved in the smallest possible quantity of 1 % hydrochloricacid, the solution was shaken up with ether, and the chlorinewas then precipitated with hot aqueous silver acetate solution.The filtrate was treated with a considerable excess of silveracetate solution, and baryta water was added until analkaline reaction began to appear. The resulting precipitatewas decomposed with sulphuric acid and sulphurettedhydrogen, the solution being freed in the ordinary mannerfrom these two ingredients, and then concentrated in vacuo.From the concentrate, histidin and similar substances wereprecipitated with mercuric sulphate, and the filtrate was thentreated with absolute alcohol. The resulting precipitate wasfirst freed from mercury by the use of sulphuretted hydrogen,then freed from sulphuric acid by the use of lead acetate, andfinally freed from lead by the use of sulphuretted hydrogen.When the liquid was concentrated in vacuo in the presenceof caustic soda, spindle-shaped crystals gradually formed,and these were extremely active. If, however, the crystalswere removed from the mother liquor, and an at tempt made

n 6 VITAMINS

t o purify them by washing with absolute alcohol, theycompletely lost their activity and became transformed intoprisms.

We see, then, that there is no difficulty in preparingeffective extracts from various foodstuffs. But the purificationof these extracts is attended with a notable loss of material,and the activity of the preparation seems to disappear atthe very moment when the last stage on the way to purityis reached. The meaning of this remarkable behaviour willbe considered later.

3. T H E PROPERTIES OF FUNK'S VITAMINS.

All that we as yet know concerning the antineuritic principleassures us tha t it is readily soluble in acidulated water oralcohol. In pure water, or 95 % alcohol, it is soluble withgreat difficulty, so tha t these menstrua extract it quiteincompletely. In absolute alcohol, ether, acetone, benzol,benzin, chloroform, and acetic ester, it is quite insoluble;and yet McCollum and Simmonds 67° make the remarkableassertion tha t acetone, though it cannot dissolve vitamindirectly out of plants, can dissolve it out of the concentratedalcoholic extracts of these. The same authorities declaretha t when vitamin has been precipitated by dextrin andalcohol and the precipitate dried, the vitamin can be extractedfrom this precipitate by benzin. Should the statement beconfirmed, we shall have a far simpler method of isolationthan the laborious and wasteful procedures hitherto employed,namely precipitation by phospho-tungstic acid, silver, ormercury.

Chamberlain, Vedder, and Williams *96 were the first tonotice the absorption of vitamin by animal charcoal. I t ispossible that this might be made the basis of the method fori ts isolation; but we have to note that these authoritiesdeclare that the vitamin cannot be re-extracted from thecharcoal either by water, alcohol, or ether. Variouswriters 537* 56°. 66* have noted that vitamin can be absorbedb y either purified or ordinary fuller's earth. On the otherhand Emmet and McKim 666 tell us that silica does not absorbi t . Another observation, which may lead to a comparativelyeasy method of purification, is that made by VoegtlinS™

FORMS OF POLYNEURITIS 117

that mastic emulsion will absorb vitamin. This is especiallyimportant in view of the fact that Voegtlin and Whitehave noticed that adenin and kindred bases are not takenup by this absorbant. From such an absorbate, by dissolvingit in benzin and shaking it up with acidulated water, a fairlypure product could be speedily obtained.

The enormous losses attendant on the various methodsof purification do not seem to depend only upon the peculiarinstability of vitamins. Perhaps the main reason is thatvitamin is, as Cooper *69 tells us, precipitated from its solutionsin conjunction with any precipitate of a nascent metallicsulphide. When we remember that attempts to purifyvitamin always entail its precipitation as a double salt ofsilver or mercury and its subsequent freeing from the metalby treatment with sulphuretted hydrogen, or else tha t thesolutions are purified by treating them with lead salts andsubsequently precipitating the lead with sulphuretted hydrogen,it will be readily understood that extensive losses cannotfail to ensue.

Vitamins are not precipitated from acid solutions by leadacetate, calcium chloride, barium chloride, or silver salts ;nor from alkaline solutions by phospho-tungstic acid. Onthe other hand when the vitamin solution has been renderedalkaline by baryta water, the vitamin is precipitated bothby barium chloride and by silver sal ts ; and in the foregoingsection we have frequently noted that it is precipitated byphospho-tungstic acid in solutions weakly acidulated withsulphuric acid. According to Schaurnann,1*2 copper acetateinduces abundant precipitation in the crude vitamin solution,but inasmuch as Funk305 tells us that no precipitation isinduced by copper salts in purified solutions of vitamin, theprecipitation observed by Schaumann must have dependedon the presence of impurities.

Regarding the reaction to mercury salts, Osborne andWakeman 978 state that vitamin is precipitated by mercuricchloride, whereas Myers and Voegtlin IJ44 actually free vitaminsolutions from other bases by the use of mercuric sulphate.Probably the precipitation observed by Osborne and Wakemanwas likewise due to the presence of such bases as adenin,histidin, e t c , as impurities.

n 8 VITAMINS

According to Tsuzuki, Shimamura, and Odake,510 vitaminforms precipitates with picric acid and with tannic acid.According to Osborne and Wakeman 97& the precipitation withpicric acid does not occur unless the reagent is added insuitable excess.

The vitamins are dialysable/S6* l8* and are comparativelyresistent to acids. Dilute sulphuric, hydrochloric, and nitricacids, have no effect on them, and according to Schaumannvitamin is unaffected by long treatment with 10 % sulphuricacid. On the other hand, most investigators agree in statingtha t it is very sensitive to an alkaline reaction, especially tocaustic alkalies. Still, even by these, vitamin is not instanta-neously destroyed; its destruction requires a time whichvaries in accordance with the concentration of the alkali,But there are two observations sharply conflicting with thesestatements. According to Williams and Seidell,56° the absorb-ate into fuller's earth is insensitive to alkali, and thevitamin can actually be extracted from the absorbate by adilute alkaline solution. Daniels and McClurg 834 tell us thatthe vitamin in haricot beans, soy beans, and cabbage willeven resist superheating (1200 C.) in the presence of sodiumbicarbonate. In this instance we are not told whether theamount of sodium bicarbonate added was sufficient to makethe menstruum markedly alkaline.

Reports concerning the sensitiveness of vitamins to heatare contradictory. According to Fujitani i a i the vitamin ofrice is destroyed by prolonged heating of the rice bran atioo° C. Funk 3*3 reports t h a t the boiling of milk suffices toreduce its vitamin content, and the same authority 334, asalso McCollum and Davis 455 agrees in stating that casein nolonger contains vitamin after it has been boiled. Abderhaldenand Lampe a89 report that fowls fed on rice become affectedwith polyneuritis sooner when the rice is boiled than whenit is r a w ; but Funk 357 points out in this connexion thatfowls consume a larger quantity of boiled rice than of raw,and we have repeatedly noted that an excess of carbohydratefood accelerates the onset of polyneuritis. When the fowlsare given a definite ration of rice, it does not matter whetherthe grain is boiled or raw.334 A remarkable observation ist ha t of Hoist, who found t h a t fowls fed on boiled potatoes 6*

FORMS OF POLYNEURITIS 119

became affected with polyneuritis, whereas fowls fed on driedpotatoes 65 developed scurvy. The vitamin would seem,therefore, to be thermostable in comparison with thecomplettin C.

Higher temperatures definitely injure vitamin. Weilland Mouriquand,47<>, 495 Voegtlin,536 Hogan,646 and Hopkinsand his collaborators Io66 agree in reporting tha t an exclusivediet of cereals, meat, or vegetable foods that have beensterilised at 1200 C , invariably gives rise to polyneuritis.Weill and Mouriquand 497 noted the same thing in the case ofsterilised unhulled r ice; and it has also been noticed in thecase of sterilised maize.632

Various observations seem, however, to conflict with theforegoing statements. According to Chick and Hume 596

yeast containing 65 % of water loses no more than an insignifi-cant amount of its protective influence through being keptfor one hour at a temperature of ioo° C. They say tha t thevitamin in the wheat germ can bear without damage twohours' exposure to a temperature of ioo° C , but at 1200 C.it is rapidly destroyed. In the already quoted paper byDaniels and McClurg we read that the vitamin in haricotbeans, soy beans, and cabbage will bear heating for half anhour a t ioo° C , and even at 1200 C , although bicarbonate ofsoda has been added; but after this treatment most of thevitamin has passed into the water. According to Rohmann,47*the baking of food for one and a half hours does not destroythe vitamins. Barsickow3<>4 reports that yeast tha t hasbeen heated to 1200 C. is still able to cure polyneuritis ; andFigueira IO46 succeeded in curing beriberi with sterilised beans.According to Osborne and Mendel, 102 boiled meat still containsconsiderable quantities of vitamins. The conflict of evidenceis explained when we recall tha t in the sterilisation of largemasses of compact foodstuffs, after exposure for one and ahalf hours to 1200 C , the heat in the centre does not exceed700 C. Bidault and Couturier I25° found that by the cookingof meat the vitamin content was markedly diminished whenthe temperature of the joint reached 900 C. in the centre, andthat the curative efiect of meat in beriberi declined notablyas the duration of the exposure to heat increased.

As a supplement to the above it may be mentioned that

120 VITAMINS

F u n k 5" found radium to have no effect upon the activityof vi tamin; and that Zilva 9l6 makes a similar report asregards ultraviolet light.

Not much is known regarding the colour reactions ofvitamin. What seems to be a fairly pure preparation assumesa deep blue colour when treated with phsopho-molybdic-phospho-tungstic acid ; b u t i t gives no colour reaction withphospho-tungstic acid alone in acid solution 488 • whereaswhen rendered alkaline with soda solution, a blue tintdevelops.56° We must remember tha t these reactions arecommon to a very large number of substances, so that we canconfidently assert that they are not specific, and we maywi th considerable probability attribute them to the presenceof impurities.

In the foregoing we have seen how extraordinarily difficulti t is to prepare a vitamin that is even moderately pure.Hence our knowledge of the composition of the vitamins isscanty The literature of the subject, for instance one ofSchaumann's papers, IW contains elementary analyses ofact ive preparations, but it is obvious tha t these latter wereimpure, so that the results of such analyses do not justify anyinferences as to the real composition of the vitamins.Fiink/SS, 205 w h o secured his vitamin as a nitrate, gives itscomposition? as 55*63 % C, 5-29 % H, and 7-68 % N, deducingt h e formula C7H l 6N03 'HNO2 . He regards it as a pyrimidinderivative, and considers i t to be either a constituent ofnucleinic acid or to be combined with nucleinic acid. Thereis much evidence in support of this view, especially the state-men t of Chamberlain and Vedder J56 that vitamin is formedfrom the decomposition of bean protein, and also the frequentlyobserved fact that autolysed yeast has a more powerful actiont h a n yeast in the original state. Hofmeister IIJ3 gives a similarcomposition for his oridin hydrochloride. The formula isC5HxxNOa • HC1. I t has a melting-point of 2400 C , and mayperhaps be a dioxypiperidin. Perhaps connected with thisis Abderhalden and Schaumann's observation 8o3 that amongt h e hydrolysis products of autolysed yeast there was" aschamin/ ' which appeared to be a dimethylpropenylamin.

A survey of the whole series of investigations and of thea t t e m p t s to obtain the antineuritic principle in a pure state

FORMS OF POLYNEURITIS 121

makes it perfectly clear that we have not to do with one singlevitamin, but with a whole class of more or less similar com-pounds. In one of his subsequent publications 273 Funkreports that he has been able to isolate from rice hulls twonitrogenous products, one of which seems to have been nico-tinic acid, whilst the other appeared to have a far more complexcomposition than had hitherto been supposed, the formulabeing C26H2ON409. From the extract of autolysed yeast hesecured, in addition to nicotinic acid, two other bases, withthe respective formulas C24HI9N5O9 and C29H23N5O9.

When it became clear that these active bodies whoseabsence was attended by the occurrence of polyneuritis werenitrogenous, it was natural to think of studying the relationshipto neuritis of the other nitrogenous compounds known toexist in the animal body or to be frequent constituents ofthe food. Thymin, cytosin, uric acid, and guanin,265, 317 alsocholin,*84> 361 purin,*84 neurin, and betain,3*i arginin, asparagin •histidin, and other amino- acids, J96 and adrenalin,289 provedquite inactive in this respect. On the other hand a numberof substances were found competent to postpone death frompolyneuritis for days or hours, though not positively curativelike vitamin. Thus strychnine 3« delayed the fatal issue;and chinin and cinchonin, in contradistinction to cinchonidin,had at least a transient efficacy.*^ According to Abderhaldenand Lampe,289 allantoin was inactive ; but Funk 3*7 statesthat its administration was followed by definite improvement,so that life was prolonged for two or three days. Hydantoinactually prolonged life for nine days. According to the sameauthority uracil led to an alleviation of the paralyses, andprolonged life for from two to six days. Whereas Williams andSeidells^o declare adenin to be quite inactive, according toFunk, this substance, and also hypoxanthin and xanthin,though they have no effect on the paralytic symptoms, cannevertheless prolong life in pigeons for from thir ty hours tofive days. Paraxanthin had a certain antineuritic effect onone occasion, but in three other cases was inactive. Thymo-nucleinic acid led to marked improvement, and prolongedlife for from nine to fourteen days, whereas yeast-nucleinic-acid gave only a four-days1 respite. Schaumann, who notedthat yeast-nucleinic acid had a definite, though transient,

122 VITAMINS

beneficial effect, 73, «* is, however, right in insisting* tha t inview of the great variations in the duration of life in suchcases, a brief retardation of the fatal issue can hardly justifyany inferences. Nor has the intensity of the paralytic symp-toms much significance, for these vary greatly from case tocase.361 The same criticism applies to the observation ofAbderhalden and Ewald,683 that atropin, in contradistinctionto pilocaxpin, seems to mitigate the attacks to some extent.

Weight must, perhaps, also be ascribed to the objectionwhich Cooper 269 has made to Ms own experiments on theeffect of chiTnn and cinchonin. He found that these sub-stances could sometimes relieve the paralytic symptoms, butthat they were quite ineffective in this respect when they hadfirst been kept for six houis at a temperature of 1250 C. Heinfers from this that in the manufacture of the quinine basestraces of vitamin from the cinchona bark sometimes cling tothe product, and this impurity gives the bases an illusoryappearance of activity as antineuritics.

Funk 974 had entirely unfavourable results with phloridjzin,and also with adrenalin, thyroid extract, and parathyroidextract, which all hasten the onset of the disease, increasethe loss of weight, and sometimes hasten considerably thefatal issue.

New parths of enquiry were opened when Funk publishedMs supposition that vitamin was a derivative of pyximidin,and still more when he was able to detect nicotinic acid amongthe constituents of crude vitamin. He ascribes the curativeeffects of rice vitamin and yeast vitamin to the compoundformed by nicotinic acid with one of the bases of the vitamin.I t . R. Williams 481, 513, etc" repeated Funk's attempts t oobtain the vitamin in a pure state; but the only pure producthe succeeded in isolating from Funk's vitamin mixture witha melting-point 2330 C. was, once again, nicotinic acid. H ethen began experimental dosage with kindred substances.Pure trigonellin (methylbetain of nicotinic acid), p-oxynicotinicacid and nicotmc-atid-nicotine-ester gave quite indefiniteresults. Somewhat better curative results iollowed theadministration of ill-defined condensation products of oxy-nicotinic acid with phosphoric pentoxide or acetic anhydride.As far as any antineuritic influence could be ascribed to

FORMS OF POLYNETJRITIS 123

/}-oxypyridin, a-methoxypyridin, a-methylpyridon, trigonellin,nicotinic acid, and betain, this was manifestly associated withthe presence of a betain group in the preparation, so thatWilliams was inclined to believe tha t some such group mustexist in. vitamin. In further experiments, a definite improve-ment in the paralytic symptoms of pigeons suffering frompolyneuritis was secured by a-oxypyridin and by 2-, 4-, 6-,and 2-, 3-, and 4-trioxypyridin. Inactive were nicotinic acid,cinchomeronic acid, chLnolinic acid, 6-oxynicotinic acid,citrazinic acid, glutazin, and the anhydrides of 2-, 4-, and6-tiioxypyridin and tetraoxypyridin. Williams went on tomake j.n observation which is likely to be of great importancein the further study of vitamins. He found tha t the effectivesubstances lost their efficacy very soon after they had beenprepared. He inferred from this tha t these substances, onkeeping, underwent a metamorphosis from the active forminto a tautomeric inactive form. He was, indeed, able toprove tha t a-oxypyridin exists in two keto-forms and oneenol-form, and that only one of these three, the keto-formwhich crystallises in needles, has a marked antineuritic effect,the enol-form in particular being" quite inactive. Similarrelationships obtain in the case of jS-oxypyridin y-oxypyridin,y-hitidin, and the anhydrides of methylpyridon, trigonellin,and betain. I n the case of these substances, only thecorresponding forms have a curative influence, and indeedthe last three have no protective influence of any kind.The protective form seems to be a pseudobetain form,and it is a matter of the utmost importance that theanimal organism is not competent to metamorphose theinactive form into the active form. Williams supposes tha tthe leading characteristic of the vitamins must be a com-pound which in respect of its structure or of its energy-contentis closely akin to such a pseudobetain ring. Compounds ofthis kind may form part of most of the simpler nitrogenoussntstances contained in the animal organs. Especially theymay be present in the nuclein bases ; and it seems likely tha tFunk's vitamins owe their efficacy, in par t at least, to somesuch pseudobetain form of nicotinic acid. Williams' accountof the various forms of the oxypyridins was confirmed byHarden and Zilva, who, however, could not find that these

124 VITAMINS

substances had any beneficial effect in cases of polyneuritis.Further researches must be undertaken before this problemwill be ripe for a decision.

The investigations of Hofmeister, who found that^ theactive preparations contained at least traces of impurities,and that the activity of these preparations disappeared whenthe purification was advanced a stage, seem to justify thesupposition that vitamins are unstable substances which arecapable of being preserved in a labile form as long as certainimpurities are present, but undergo a metamorphosis into astable form as soon as these impurities are removed. Hithertowe have paid too little attention to this possibility, vftdch. islikely to prove of decisive importance in the further studyof the vitamins.

4. OCCURRENCE OF THE VITAMINS.

Vitamins are present in almost all anmial and vegetablesubstances used as food. In the animal body they are lessabundantly stored in the muscles (which, when fresh, alwayscontain a sufficiency) than in the parenchyinatous organs.In plants we find them especially in the leaves and othergreen parts, that is especially in the vegetative organs; whereasthe parts used by the plants for storage, such as bulbs, tubers,and roots, contain them in less abundance. Still, the amountof vitamin in potatoes, for instance, is so large that evenboiled potatoes are useful, not merely as a remedy, but also asa prophylactic. Fruit, too, in the kitchen sense of the term,is rich in vitamin, and so are seeds. Within the individualorgans, the vitamin content of the various tissues differsgreatly. Especially does this apply to seeds, whose endospermcontains so little vitamin that its use as an exclusive diet,or even as a predominant constituent of the diet, is thecharacteristic cause of beriberi. The gOTis, of seeds areespecially rich in vitamin. In like manner" tiKe vitamincontent of eggs, which are the animal counterparts of seeds,is concentrated mainly in the yolk.

We can readily understand, therefore, how harmful it iswhen, in lands vhere bread forms the staple diet, the demandsof a crazy standard of luxury should lead people to consumebread made only of endosperm. We have already learned that

FORMS OF POLYNEURITIS 125

in North America epidemics of beriberi have followed theuse of such bread. We saw also tha t in 1911 the Japanesemaintained tha t the spread of the railway system in theircountry must be responsible for the increase of beriberi alongthe new lines of communication. Since there had been nochange in the mode of life of the Japanese peasants, thesescientific authorities believed tha t the diffusion of an infectiveagent was responsible. But they overlooked the fact that ,thanks to railway developments, the peasants had not merelyacquired increased facilities for marketing their own agri-cultural produce, but had also become contaminated withthe refinements of urban life, and had heen provided withfinancial resources enabling them, to buy polished rice milledin the towns and to abandon the use of the partially hulledrice formerly prepared in their own hand mills and foot mills.WillcoxI0*5 has shown that among the European troops inMesopotamia during the recent war (men who were fed mainlyon meat, and on bread made from the finest wheaten flour),epidemics of beriberi repeatedly occurred when circumstancesmade it necessary to replace the ration of fresh meat by tinnedmeat. The fine white flour contained extremely little vitamin,which was, however, sufficient when supplemented by thevitamin in fresh mea t ; but when the meat had been sterilisedhy prolonged exposure to heat (probably the juices of themeat, and therewith the vitamins, J383 had also been removedby pressure) the supply of vitamin was altogether inadequate.

Apart from these canning processes, the vitamin contentof food can "be so greatly reduced by excessive sterilisationor by some other faulty method of preparation (as by throwingaway the water in which the food has been boiled) tha t i tis no longer adequate to prevent the onset of polyneuritis.Over-roasting, likewise, can seriously reduce the vitamincontent of meat, although the other vitamins in the diet willin general make good the deficiency. If, however, in suchcases the amount of food taken be reduced owing to axniteindigestion, or if the bodily requirement be increased by theonset of some febrile disorder, or the like, the vitamin contentof the food may no longer suffice the needs of the weakened"body, and there may ensue, if not beriberi, a t least a moreor less marked attack of polyneuritis. Such cases are

126 VITAMINS

commoner than is generally supposed, especially in Europe,but owing to defective knowledge of their etiology they areapt to be confounded with other diseases.

Amongst the poorer classes of the population, such occur-rences are fairly easy to interpret, but it is noteworthy t h a tattacks of polyneuritis are by no means rare in Europe amongwell-to-do persons belonging to the cultured stratum ofsociety. If in such instances we investigate the causes ofthe disease we shall usually find that the patient has recentlyhad an acute gastric or intestinal disorder. He has thereuponbeea prescribed a very rigid diet, consisting of food tha t shallbe easily digestible and simultaneously as " nourishing " aspomhle. In consequence of this the stomach and bowelhaw beea increasingly disaccustomed from their propertasks—tht patient, who is usually a neurasthenic, payingsedulous attention to the behaviour of his bodv all the while.

FORMS OF POLYNEURITIS 127

as minor digestive troubles, disinclination for work, and aproneness to excessive fatigue. By degrees, weakness in thelegs and unsteadiness of gait appear. Paraesthesia is noticedin the nerves of the lower extremities, and circumscribedanaesthetic areas can usually be discovered in various partsof the skin below the knee. The knee-jerks, which are aptto be somewhat exaggerated in the initial stage, are by now

(~>>rnrnpnHnp- HrmiAtnrv weakness is shown

128 VITAMINS

disappearance of the patellar reflexes, extensive hyperaesthesiaof the skin, and severe paraesthesias of various kinds, thesesymptoms indicating grave disorders of muscle and nerve.Only in the later stages do we find complete anaesthesia andreaction of degeneration. Intelligence is unimpaired to thelast, although fits of depression are frequent, and wherepredisposition exists even mental disturbance may ensue.The later stages are always attended by profound apathy.

b. Pathological Anatomy.

If we examine the nerves in human beings that have diedof beriberi and in animals that have succumbed frompolyneuritis, we usually find marked degeneration of thefinest nerve endings—a degeneration gradually spreadingtowards the centre, and ultimately showing itself in the spinalcord and even in the brain. In the peripheral nerves, thechanges consist of degeneration of the medullary sheaths, andof degeneration and subsequent complete destruction of theaxis cylinders, until in the end the latter are completelyreplaced by nucleated neuroplasma cylinders, which Diirckregards as a nervous matrix tissue. This view is doubtlesscorrect, for even though complete restoration of the nervesmay take a long time, the administration of vitamin willreestablish nervous functioning in a marvellously shortperiod. Moreover, we frequently find extensive degenerationin nerves supplying muscles that have been working quitesatisfactorily.

The next most striking feature to the pathologist is theatrophy of the muscles in the affected parts of the body, inwhich sometimes a typical myositis can be noted. The atrophyis distinguished from the ordinary atrophy of inanition bydefinite signs of degeneration : the cross-striation is obscured;the sarcolemma sheaths have often b u r s t ; their contents aresoftened, contain fat-droplets, and have here and there exudedfrom the sheaths. The nuclei of the muscle cells are markedlyincreased in number.

Similar conditions are observable in severe attacks ofneuritis due to other causes, and notably in those dependenton intoxication. Hence it has been widely believed that thedisease must be a primary polyneuritis due to intoxication.

FORMS OF POLYNEURITIS 129

Nocht,74 however, pointed out as long ago as 1908 tha t thereare certain fundamental differences between the degenerationtypical of toxic neuritis and that typical of beriberi, and hetherefore considered that the nerve degeneration of the lattermust be regarded as purely atrophic. This theory is supported,above all, by the fact tha t even in the nerve bundles thatare most gravely affected, certain fibres still appear intact,whereas in toxic degeneration all the fibres of a nerve aresimultaneously affected.

Medical observers in general are of opinion tha t the nervedegeneration is the primary lesion, and that the atrophy ofthe nmscles is merely a consequence of this. In my opinion,there are important grounds against such a conclusion.First of all, atrophy of the muscles, with subsequent degenera-tion of the muscular fibres, frequently occurs before there isany visible lesion in the nerves; and, secondly, the nervelesions are not proportional to the severity of the pareses orparalyses. I t is true tha t Koninger 7 maintained in 1884that the nerve lesions were primary, and tha t the typicalsymptoms of the disease did not appear until after the onsetof the nerve lesions. Vedder and Clark,^ , 307 again, whostudied the lesions in the brain, deny the peripheral natureof the disease, and consider that the primary source of thesymptoms is in the central nervous system. But these sameobservers, and also Eijkman, Cooper,3JI and Schaumann,3i<>have repeatedly insisted that there is no demonstrable connec-tion between the intensity of the paralysis and the degreeof nerve degeneration. Attentive study of published casesshows that there have been many in which severe paresesor complete paralyses occurred, cases which proved fatal,without there being any nerve lesions discoverable on post-mortem examination; or at most there was a degenerationof the medullary sheaths, but in cross-section of the nervesno degeneration of the fibres could be detected. On theother hand, cases are frequently encountered in which thenerve lesions are most extensive, so that hardly a single healthyfibre can be detected even in the big nerve trunks, and yetbefore death no paralyses have been noticed and hardlyeven slight pareses.

I 3 o VITAMINS

c. The Forms of the Disease.

We must infer from these considerations that we areconcerned, not with conditions that bear a causal relationshipone to the other, but with parallel manifestations of a commoncause. The pareses and paralyses are obviously not a conse-quence of the nerve lesions ; or, at any rate, are not necessarilyso, for they can just as well be explained as the outcome ofa primary affection of the muscles. Indeed, some haveattempted to argue that the nerve degenerations, when theseare slight, are a consequence of the degeneration and theputting out of action of the muscles supplied by the ^affectednerves.

The most probable explanation is that the nerves andh the muscles degenerate and atrophy more or less simultane-

ously owing to some defect in nutrition. This theory is sup-ported by the fact that the disease is always introduced bya marked falling off in weight, and we have already learnedthat both the nitrogenous balance and the total-ash balanceare negative long before the outbreak of the illness.

In association with cases of beriberi of the type we havebeen describing, known as dry beriberi, we frequentlyencounter instances of the so-called wet beriberi, casescharacterised by oedema. The oedema, like the pareses,appears distally, spreading upwards from the toes or fromthe finger-tips. Gradually the entire lower extremities areinvaded, then the lower part of the trunk, then the thoraxand the neck, until ultimately the face may be so much swollenthat the features become unrecognisable; hydropericardium,too, is exceedingly common. In this form of the disease,there is usually cardiac dilatation without valvular lesionsand without hypertrophy. The pulse is regular, but feebleand frequent. In prolonged and severe cases, when the hear tis overworked, there may be actual insufficiency at the dilatedcardiac orifices, and murmurs may become audible. Theurine is always greatly diminished, rich in urates, but usuallyfree from albumin and casts, this showing that there is norenal irritation. In wet beriberi, the muscular atrophy isnecessarily masked by the dropsy, and even the pareses m a ybe more or less obscured. If, however, by rest in bed and

FORMS OF POLYNEURITIS 131

suitable diet, the dropsy be relieved, it becomes plain t h a tmuscular atrophy is present in such cases also. When thetreatment is successful, there is an enormous discharge ofurine, the oedema disappears with marvellous rapidity, and thepatient now presents the typical picture of atrophic beriberi.

Sometimes we encounter a third type of beriberi, whichshould really be regarded as an aggravated form of dropsicalberiberi. Whereas the normal course both of atrophic andof dropsical beriberi is chronic, so that the cases sometimeslast for years, the acute cardiac form of beriberi is very rapidin its onset, and may even terminate fatally in a few hoursfrom l^eart weakness. The exciting cause is, as a rule, somesudden demand upon the energies, as through very unusualbodily or mental exertion, the onset of an acute disease, ora major operation. There promptly ensues a feeling of seriousillness, with extreme precordial anxiety, greatly increasedfrequency of the breathing (which is convulsive and anxious),marked cyanosis, violent retching, and sometimes haemate-mesis. The temperature is usually normal, the pulse is fullbut compressible and extremely frequent, with a loweredblood pressure; the heartbeat is violent, conveying a shockalong the great bloodvessels. A natural consequence of thiscondition of the circulation is a marked reduction in theurinary excretion, culminating in suppression of urine andthe onset of widespread oedema. Death takes place incollapse, with diaphragmatic paralysis, pulmonary oedema,a galloping pulse, and in many cases a clouding of the intelli-gence ; in some instances, death takes place in coma.

If we wish to analyse the etiology of beriberi, we haveto reckon with three main groups of symptoms. Mostcharacteristic, in my opinion, are the atrophy and degenerationof the muscles, leading to the pareses or paralyses. Secondlywe have to consider the nerve degeneration, which we shallincline to regard as a contributory cause of the paralyticsymptoms only when the nerve degeneration is stronglydeveloped—unless, indeed, we accept the view of manyauthorities who hold that the pathogenic factors give rise toa disorder of nervous functioning long before any anatomicalchanges have taken place. I t seems to me difficult to creditthe existence of such a functional disorder, seeing tha t the

I 3 2 VITAMINS

reports of experimentalists repeatedly mention that theconductive power of the nerves for stimuli was retained. Thethird group of symptoms comprises the cardiac weaknessand the onset of oedema.

6. ANALYSIS OF THE MORBID MANIFESTATIONS.

a. Significance of the Symptoms.

In the previous section we have learned that these threegroups of symptoms may occur almost independently eachof the other, although muscular degeneration appears to bea constant feature of beriberi. I t is invariably present, also,in the polyneuritis artifically induced by an ill-balanced diet,but this form of the disease is almost always characterisedby the presence of more or less oedema. Some investigatorsaffirm that the following three types can be distinguishedamong cases of polyneuritis: simple neuritis; neuritisaccompanied by general enfeeblement; and extremely acutepolyneuritis without neuritis properly speaking but character-ised by grave debility. As regards the first of these, whichis rare, I cannot help suspecting that atrophy is really present,but is masked by the oedema. For in experimental poly-neuritis, also, we invariably find that the other symptoms donot appear until great bodily wasting has occurred, amountingto from 23 % to 30 % of the weight. Many authors havebeen disposed to refer this wasting to a loss of appetite inanimals kept upon an ill-balanced diet. In answer to thiscontention, it has repeatedly been shown that the loss ofweight usually begins directly the experimental animal isput on the pathogenic diet, and may be considerable beforethere have been any signs of a loss of appetite. Even whenChamberlain, Bloombergh, and Kilbourne *45 had recourse toforced feeding (cramming), they found that the onset ofpolyneuritis was always preceded by a loss of weight amountingto at least 21 %. It is true that in Fraser and Stanton'sexperiment, in which forced feeding of pigeons with polishedrice was practised,™* the weight of the birds remained almostconstant—with the result, we may parenthetically remark,that the onset of polyneuritis was speedier than ever. Nopost-mortem examination appears to have been made in

FORMS OF POLYNEURITIS 133

these interesting cases, bu t it seems not unlikely tha t thebody-weight was maintained, partly through oedema, andpartly through the putting on of fat, although grave musculardegeneration may have ensued. However this may be, theconditions were so exceptional that Fraser and Stanton 'sexperiment cannot help us to decide the problems of etiologyin the absence of post-mortem examination.

The occurrence of oedema in beriberi is a secondarysymptom, one which has nothing to do with the essentialdisease. The eighth chapter of this work is devoted tomalnutritional oedema, and in that chapter we shall have torefer once more to the onset of oedema in cases of beriberi.We certainly have to do here, with an intercurrent affection,and are reminded of the frequent associtaion of beriberi withscurvy.

If the muscle degenerations and the nerve degenerationsare to be regarded as parallel symptoms running an indepen-dent course, we may perhaps assume tha t our food containstwo classes of vitamins, the absence of one of these givingrise to the nerve lesions, and the absence of the other givingrise to the muscle lesions. There is much evidence in supportof such an assumption, a notable point being tha t mostauthorities incline to assume the existence of two distinctclasses of vitamins. However, these respective classes seemto have different effects from those we might expect in accord-ance with the foregoing assumption. To clear up the mat ter ,a more detailed examination of the data contained in theliterature of the subject must now be undertaken.

First of all it is necessary to bear in mind the unanimoustestimony of authorities tha t a natural nutrient, in so far asit is active at all, does not merely cure this or tha t symptomof beriberi or experimental polyneuritis, bu t relieves theentire syndrome. In beriberi, for instance, it does not mat te rwhether we give rice bran, beans, or green vegetables, all ofwhich are very active remedies, or whether we give one ofthe less powerful agents, such as milk. Provided the dosageof the remedial food be sufficient, a complete cure promptlyensues. But the results are very different when for curativepurposes we use extracts made from the remedial nutr ientsand Schaumann tfl emphasises the assertion tha t the qualita-

134 VITAMINS

tive no less than the quantitative effect of such extracts isless in proportion as the purification of the substance has beenmore thorough. Vedder 3*4 points out that crude vitaminsemployed as antineuritic remedies are from 20 to 30 timesless effective than the foods from which they were originallyderived containing the same amounts of these substances.At the same time, the universality of effect has disappeared fromthe extracted crude vitamins, and each of these has an effectpeculiar to itself.

That is why so many authorities *84, 375,5*6, 619, 666, 683, 691,731, 874> 1040,1066, etc j i a v e c o m e t o consider that at least twovitamins are indispensable for a cure. We may recall theobservation of Funk *73 that the bases he isolated from ricebran and from yeast respectively were inactive when usedseparately, but were able to cure the paralyses whenadministered simultaneously.

b. Effects of Funk's Vitamins,

Certain investigators regard the vitamins as active remediesThus, according to an early paper by Funk,375 they definitelycure experimental polyneuritis in animals; Segawa 3*3expresses the same opinion. The latter, however, noticedthat the marasmus attendant on these cases was not relievedby the vitamins, and this led him to regard the marasmusas a secondary symptom, an outcome of the malnutritionconsequent on the lack of balance of the diet. We havealready seen that there are numerous indications against anysuch theory. Marasmus is not a secondary symptom inthese cases; it is the first and most fundamental symptom.Pareses and paralyses are superadded as further characteristics.Marasmus and the nervous symptoms taken together combineto form the typical picture of beriberi.

In 1911, lecturing in Berlin, Schaumann for the first timerecounted the experimental evidence to prove the almostmiraculously beneficial effect of vitamins in pigeons paralysedby polyneuritis. But this cautious investigator pointed outtha t the birds' restoration to health was apparent merely.He said that rice bran must contain other substances whichhad to be given in addition to the vitamins if a real cure wasto be effected. In default of these, the animal would die

FORMS OF POLYNEURITIS 135

notwithstanding the relief of the paralyses. About a yearlater, Strong and Crowell ™3 reported tha t when experimentalanimals were fed on polished rice, the addition of alcoholicextract of rice bran to the diet sufficed to prevent the onsetof paralyses ; and tha t in animals suffering from experimentalpolyneuritis the extract would dispel paralytic manifestations,even when severe, within a few hours or d a y s ; bu t theadministration of the extract did not prevent the death ofthe experimental animals. Vedder and Clark 23%> 3°7 foundthat alcoholic extract of rice bran gave relief only in thefulminant form of polyneuritis, being then competent to removethe paralytic symptoms. Later, Vedder and Williams 284noted that the different symptoms of beriberi required differentvitamins for their cure. The Funk's vitamins precipitableby phospho-tungstic acid relieved the paralytic symptoms,and these only; on the other hand, the filtrate after precipita-tion by phospho-tungstic acid was useless for polyneuriticparalysis, but had an unmistakably beneficial influence uponthe atrophy. I n his important paper of 1914, Schaumannagain and again insists that Funk's vitamins are only of useto relieve the paralytic symptoms, whereas alcoholic extractsof bran exert a complete prophylactic and curative influence.

Even more effective than alcoholic extracts of the bran, ,are extracts of rice bran made with water or with weaklyacidulated water. Besides promptly relieving the pareticand paralytic symptoms, such extracts bring about markedimprovement in the general condition, and lead to an increasein weight though not to a complete return to the no rma l^*An extract of yeast similarly prepared with water containingo • 3 % of hydrochloric acid acts in the same way, bu t farmore powerfully. If yeast, after removal of the fat, is firsthydrolysed with 10 % sulphuric acid and then extractedwith water, the resulting extract is found by Schaumann s^to be peculiarly efficacious against the paralytic symptoms,both as curative and prophylactic, but it is not otherwisevaluable. In like manner, extracts made from katjang-idjobeans after predigestion with pepsin and hydrochloric acidare useless to prevent loss of weight and emaciation thoughactive against pareses and paralyses. According to Voegtlinand Towles,365 a watery extract of the spinal cord of

X36 VITAMINS

the ox was effective only against the paralytic symptoms.Vedder 3°7 noticed that insufficient supplies of vitamin cantetard the onset of pareses and paralyses, but do not preventloss of weight and emaciation ; the period of incubation may!be prolonged to as much as a year; when death comes atlast, it is usually sudden. Schaumann36* had the sameexperience. Adding inadequate quantities of alcoholic extractof yeast to a diet of polished rice, he found that the onsetof pareses was thereby retarded, and yet the loss of weightwas greater than in control animals fed on polished riceunsupplemented. Still, the animals receiving the yeastextract lived longer, and (except for the loss of weight)apparently in good health—until suddenly grave paralysissupervened, and death soon followed.

c. Differences between the Effect of Funk's Vitamin and thatof water-soluble B or that of water-soluble D.

Williams and Seidells60 report some interesting observa-tions. In animals fed on polished rice, the fuller's-earthabsorbate from autolysed yeast was administered; thereuponthe paralytic symptoms disappeared, and concomitantly therewas a notable improvement in the general condition. If theabsorbate, before being added to the food, was treated withdilute alkali, it ceased to affect the general condition, thoughit was still competent to relieve the paralyses. In theoriginal autolysate of yeast (before the fuller's-earth absorbatehad been prepared from it) the effect of alkalies was theopposite; if the autolysate was allowed to remain in analkaline solution for a considerable period, the effectivenessagainst the paralyses as a prophylactic and a curative dis-appeared, but the solution continued to bring about notableimprovement in the general condition of the animals fed onpolished rice. These observations have not been confirmed,but we know that vitamin is absorbed in a fairly pure stateby fuller's earth; and since this absorption appears to be aphysical reaction in which no decomposition of the vitaminneed be expected to occur, we have theoretical grounds forsupposing that the vitamin in this absorbate will really bepure. Now Emmet and McKim666 have been able to provethat in pigeons suffering from polyneuritis the fuller's-earth

FORMS OF POLYNEURITIS 137

absorbate, though it relieves the paralytic symptoms, isquite without influence upon the loss of weight and theemaciation. These authorities therefore infer t ha t the prophy-laxis or cure of the marasmus requires the presence in thefood of certain hitherto unknown substances, over and abovethe vitamins.

Sugiura776 states t ha t both the alcoholic extract ofcarrots and the crystalline substance prepared from yeastin accordance with his method have a powerful remedialinfluence in acute cases, as far as the paralytic symptomsare concerned, but do not relieve the m a r a s m u s ; in chroniccases these preparations are of no use whatever. Weill andMouriquand 731 likewise found vitamin effective in acutecases of paralysis on ly ; in chronic cases of beriberi, moreextensive pathological changes must have taken place, changeswhich vitamin could not influence. Abderhalden andSchaumann 8o3 expressly declare tha t the eutonins (see p . 22)rapidly and effectively relieve the nervous disturbances, bu totherwise are devoid of beneficial influence; whereas ricebran and yeast (substances from which eutonins can beextracted), are strongly curative. I t is interesting to note,moreover, that although an alcoholic extract of yeast 361 canrelieve paralytic symptoms or prevent their onset, its adminis-tration tends to have unfavourable effect as regards the lossof body-weight. On the other hand, yeast which had beenextracted with large quantities of alcohol—even four timesin succession—was able to prevent or cure the disease, theloss of weight in these cases being only from 6 to 7 %.

McCollum and Simmonds 69* have been led by theirresearches to believe tha t only the nervous disturbances arereferable to lack of vitamin. Hopkins and his collaborators Io66

come to the same conclusion.We have quoted in this connexion no more than a few

extracts from the literature of the subject. The reports ofthe other observers all have the same trend, and i t is needlessto cite them more copiously. Cooper,*69 whose experiencewas similar, attempted to ascertain the minimal quantitiesof a nutrient that must be given in order to prevent, in oneseries of cases paralytic symptoms, and in another series ofcases loss of weight, on a diet of polished rice.

138 VITAMINS

Fish was comparatively ineffective. Ten grammes ofpike had no effect either on the paralyses or on the loss ofweight.

Many investigators were, however, strongly disinclined toadmit that there could be other vitally important substancesin the food, substances still unknown to us. The presenceof a fundamentally important substance in fat had beenproved. This was absolutely distinguished from the anti-neuritic principle by its solubility in fat, and had thereforebecome known as fat-soluble A. Stepp 5*7 had given experi-mental proof that vitamin could not substitute fat-soluble A,and that the latter could not substitute the former. r Sinceall the other essential substances were soluble in water, it

Bakers' yeastYolk of eggBarley, decorticated

„ undecorticatedBullock's heartSheep's braindentilsLean beef

Prevent Paralyses.

Fresh.

Grammes.

33*755

121520

Dried.

Grammes.2*5I#53'24*522'535

Prevent Loss of Weight.

Fresh.

Grammes.2*5

107*5

105

3 to 63020

Dried.

Grammes.°"5.5

92

0•6 to 1•265

was assumed that there was only one vitally essential water-soluble principle—vitamin. McCollum and his collaborators 490were loath for a long time to tolerate the supposition thatthere are other unknown substances in the food which areindispensable to life and health. But inasmuch as McCollum'sown work had shown beyond doubt that natural nutrientscontain water-soluble substances essential to growth, Americanauthorities did not hesitate to identify this growth-factor,this water-soluble B, with Funk's vitamin. The water-soluble antineuritic substances and the growth-factor did, infact, react similarly in many respects towards heat and otheragents, so that the assumption of their identity did not lackjustification. Eddy 5*4 showed some years ago that, justlike vitamin, the growth-factor could be absorbed from anextract of pancreas by Lloyd's prepared fuller's earth, and

FORMS OF POLYNEURITIS 139

could be precipitated by phospho-tungstic acid; and heproved that both preparations had an antineuritic influence.Drummond 6l9 arrived at similar results in his study of theantineuritic principle and the growth-factor in yeast, and hetherefore came to the conclusion that the two substances wereidentical. Lecoq IO76 describes the growth-factor as solublein water and alcohol, insoluble in fatty menstrua, resistantto acids, sensitive to alkalies, absorbable by colloidal aluminiumoxyhydrate or iron oxyhydrate, and destroyed by prolongedheating at 120° C.

There was, consequently, considerable evidence in favourof the; view taken by Drummond,874 and by other Britishauthorities "94. 1554 as recently as 1922, that the water-solubleantineuritic principle and the complettin B are the samesubstance. But the objections to any such assumption arestill stronger. As long ago as 1913, Funk 324 had shown tha ta diet may be rich in vitamin and nevertheless inadequateto promote growth and even to maintain body-weight. Abder-halden and Ewald 683 and also Abderhalden and Schaumann,8o3insist tha t the addition of extracts rich in vitamin to polishedrice does not make of the latter an adequate food, whereaspolished rice supplemented by a sufficiency of extract ofrice bran is able to maintain life upon a normal footing.Hopkins *°a had shown as early as 1912 tha t whereas thevarious preparations of vitamin could not sustain growth,aqueous extracts of bran or yeast promoted normal growth

d. Differences between water-soluble B and water-soluble D

These results might be interpreted as showing tha t thereis a distinction between vitamin and the growth-factor, butthat the growth-factor is identical with the still unknownwater-soluble substance which is essential in addition to thevitamins to the complete cure of beriberi and experimentalpolyneuritis. Bostock 3 l6 assumes this identity as regards theactive principles in rice, Byfield IJ53 as regards those in orangejuice, and Eddy and Stevenson I2O5 as regards those in ricebran. mAbderhalden I04° had proved in the case of yeastthat the antineuritic principle, in contradistinction to vitaminbut in conformity with the growth-factor, was practicallyinsoluble in alcohol. When, however, we carefully study such

140 VITAMINS

researches as those of Osborne and Mendel concerning thecomplettin content of various parts of the wheat grain, adifferent result is reached. We have already learned t h a t inthis grain the antineuritic principle is concentrated in thegerm, whereas the pericarp is somewhat less richly suppliedthan the germ, and the endosperm contains exceedingly little.According to Osborne and Mendel, however, in young ratsloss of weight can be prevented when wheat germs are usedas the only source of complettin, but in these circumstancesgrowth does not occur. Although endosperm contains asmaller quantity of water-soluble complettins, when givenin conjunction with the germs endosperm can sustain growthin rats. This observation can only be explained on theassumption that, as far as the growth-factor is concerned,the endosperm of the wheat grain must contain more thanthe germ. The water-soluble complettins in the germ mustconsist mainly of Funk's vitamins and the as yet unknownwater-soluble antineuritic principle. In endosperm, on theother hand, there must be an adequate supply of the growth-factor, but Funk's vitamin and the antineuritic principlemust be almost completely lacking.

An observation made by Sugiura and Benedict 98° can besimilarly explained. A diet of bananas and casein is adequatefor the maintenance of lactating rats, especially if supplementedby the antineuritic principle in the form of yeast added tothe food to the amount of 0.5 %. But the milk secreted insuch a diet does not sustain growth in the sucklings. Thetrouble cannot be ascribed to the protein, inasmuch as we havelearned from other experiments that banana protein is ren-dered adequate by the addition of casein. Nor can the defectin the diet arise from a deficiency of inorganic nutrients ; forthe abundant supply of bananas is a guarantee that the foodwill contain an excess of bases, and although there may bea partial lack of calcium salts, these could be adequatelysupplied from the osseous system of the mother rat. Theobservers found that in these cases the addition of 0-5 % ofprotein-free milk rendered an adequate production of milkpossible, and they therefore assumed that the milk thus addedmust contain some organic substance essential to growthwhich had been wholly or partially lacking in the unsupple-

FORMS OF POLYNEURITIS 141

mented diet. This substance could not be the antineuriticprinciple, for there was an abundance of tha t in the yeast.I t would, of course, be possible to suppose tha t the antineuriticprinciple is able when administered in comparatively smallquantities to prevent polyneuritis and to guard against lossof weight, but that in order to secure normal growth largerquantities are requisite than can be supplied by the amountof yeast actually given. On that theory, the requisite supple-ment of antineuritic principle had been furnished by theprotein-free milk. We shall see, however, in a moment t h a tthis plausible interpretation is untenable. The experimentsof Oshprne and Mendel "S1 have, in fact, shown tha t yeastalso contains the growth-factor, so that when the supply ofmilk is inadequate, normal growth can be sustained throughsupplementing it with small doses of yeast.

Loeb and Northrop 569 found that the growth-factor inthe yeast was far more thermostable than the antineuriticprinciple; but whereas the latter was resistant to alcohol,the former was destroyed by it. However, this observation"'was made on the larvae of flies, and we are hardly justifiedin regarding it as convincing evidence in the case of higher'animals. A fortiori this criticism applies to the researches ofEmrnet and Stockholm,I2O3 Eddy and Stevenson, I305 Miller,1286

and Whipple,I287 who used yeast as the test object in theirexperiments on growth; for subsequent investigations haveshown tha t the modifications they observed in the growthof yeast were referable to numerous other factors, such as theprovision of a better mixture of salts, the supply of carbo-hydrates, etc.

Nevertheless, the researches of Emmet and Luros,120*who fed pigeons and rats on tmhulled rice, have shown clearlytha t there are differences between the water-soluble antineuriticprinciple and the growth-factor B. They found tha t theantineuritic principle can tolerate one hour's heating a t1200 C. under a pressure of 15 lbs., but tha t it is partiallydestroyed by two hours in an air chamber at the same heatand pressure, and completely destroyed by two hours' exposureto the same heat at a higher pressure. In extracts, the anti-neuritic principle was even more sensitive to heat. Thegrowth-factor, on the other hand, was not notably affected

142 VITAMINS

by exposure to the same conditions. McCollum andParsons X3«> were led subsequently to a different view, findingthat when milk was boiled, the antineuritic principle wasdestroyed more rapidly than the growth-factor.

Funk and Macallum563 tell us that the growth-factor isless stable and is more readily destroyed than the antineuriticprinciple in the process of purification by phospho-tungsticacid and silver precipitation. We can hardly accept this asa proof that the two substances are distinct, seeing that themethod is obviously unsuitable for the isolation of the growth-factor. The method is the one employed by Funk for theisolation of vitamin, and we may therefore presume that theterminal product is simply a vitamin containing growth-factoras an impurity. We are all the more justified in such a conten-tion seeing that, on the one hand, Funk and Macallumthemselves tell us that the terminal product is very likeFunk's vitamins, and on the other hand other observers haveproved that both the growth-factor and the antineuriticprinciple are merely obtained in small quantities as an acci-dental impurity through precipitation by phospho-tungstic acid.

More convincing, in my view, is the statement of Sugiuraand Benedict 967 that the growth-factor is destroyed by expo-sure to radium, whereas the antineuritic principle, as wehave previously learned (p. 120), is unaffected thereby. Veryimportant, likewise, is the fact observed by Verz&r and Bogel I27°that when growth-factor is subcutaneously injected it has noeffect on either the glandular secretions or the blood-pressure,whereas the antineuritic principle, as will subsequently beshown, has a specific influence on the glands.

Summarising all these considerations, we are led to endorsethe view first expressed by Mitchell 979 that the vitamins,the water-soluble antineuritic substances, and the water-soluble growth-factors, form three distinct classes.

e. Behaviour of the Glands.

To complete the picture, we must give an account of theanatomical and physiological effects of a lack of vitamin andthe supply of vitamin. In supplement of what has alreadybeen said it should be mentioned that Funk has found changesin the brain. In cases of polyneuritis, the brain contains

FORMS O F POLYNEURITIS 143

considerably less nitrogen and 20 % less phosphorus t hannormal.J97 Schaumann points out that the glands, no lessthan the muscles, undergo gradual atrophy. Portier,1]co3Tan Driel,ri39 and Bierry, Portier, and Randoin,IX97 report ,in conformity with numerous other observers, the same facts. ,When there is a lack of vitamin, there occurs atrophy of thetesticles, spleen, ovaries, pancreas, heart, liver, Iddneys,stomach, thyroid, and brain, the onset being practically inthe order named. I n the glands, t he parenchymatous tissuegradually disappears, being replaced by connective t i s sue ; tthe spermatazoa vanish from the testicles. The secretion ofsaliva,, gastric juice, pancreatic juice, bile, and intestinaljuice, declines. I n contrast with the other glands, the pitui-tary body and the adrenals become enlarged, b u t the secretion of -adrenalin is greatly reduced, although the adrenals apparently*contain more of th is substance than usual.

The administration of vitamin rapidly changes t hepicture ; the glands resume their secretory activities, and bydegrees the atrophic changes disappear. In young animals,the testicles, even though they have degenerated so extensivelythat the active cells have heen almost entirely replaced byconnective tissue, re turn to the normal and produce sperma-tazoa once more.TIO7 With the reappearance of the digestivesecretions, the appetite, which has been in abeyance, returns,and is often ravenous. Extremely characteristic is an observa-tion by Fletcher, quoted by Fraser and Stanton.108 At theheight of experimented polyneuritis, "when pigeons refusefood and are forcibly fed, t he rice remains unchanged in thedistended crop. B u t if, now, a small quantity of rice polishingsbe introduced into t he crop, the accumulated rice is speedilydissolved, and the normal powers of digestion return, with arevival of appetite. Uhlmann,63^ 755 using the commercialpreparation known as orypan,884 has made a detailed study ofthe effects of the administration of vitamin in birds andmammals suffering" from experimental polyneuritis. I ngeneral, he found t h a t vitamins have the same effect whetheradministered "by mouth or by subcutaneous or intravenousinjection. Above all, there is a powerful stimulation of theparasympathetically innervated glands, the action resembling(though not identical with) tha t of pilocarpin, nniscarin, or

I 4 4 VITAMINS

cholin, and similaily amMrt l bv a t f ^ m . \ JMIL* nl.treffects, Uhlmann rcfcis in uuu:vi<\ nvu«n • J ** i 4 u u *i .tears, sweat, saliva, iidsttu jm«<-, bi!», JMJ. < ai \ *i< *, m4intestinal juice; in irsj*ut <»f th< !• f* ^ M "*<«} n , hi»observations h a w IHTII um!uni<'<l I»v \«.»/tIm ai, i M \ o "*and also by Willrox.'"'* AnnjiliJi*: *>* I Mm .i*»«. th* nnvilating influence on tlw jnuui*a. i . *ilin t<* t\a *4 ^ M u i ,though lckss powiTful.

Willcox n»i>ortft that the in« i< t««iv •*« ti »itn ».{ th* r1*n*l*are restored by the administrate»n *•! ^i^in*been able to find any tnt*utti»u <«i th<* *i i^trophied pituitary Ixidy ami th«* a^itii iK.whether these remain enl;tu*^}, ••! u l u i n ! *

The unntriated mtwlfs , im !«•,, than IIHare powerfully stimtilatrd l*v iuy<H'iU'action resembles that oj mj^ t ton . <4 |*il«or cholin, and in similarly inhibit* 4 l*v *IIM1On the heart, vitamin works bv UMvtrf |**M«tion, and the enhanced vi;{om (4 th<* *it#;-*tt ithe arteries in the* form of a stioitf* jmlexpand and the l>Iood-jii«'s%«iri: f.ttl*,

The fart that the pitmtarv b^ lv am*! tb«* .»<h«iMJ.. $ncontradistinction to all tin* r^thn ptifi4', un<\* ti*t** Uvi^t\t<>yhyf

cannot fail to attract vprci.il 4ff«ijfioji Jt $» 4JI th*- tn**t*<remarkable, then, that in tlu* uli«4*4 Jif* t^tm** <•< tl»«- %*i!«j**lno further reference should be m,nh* to tl«a * )««<nlur r**uu<4iof the pituitary body, although th*- t<.uti<*n mu.t itninf* .tlybe the expression of sum** sp^i,*! r!<!n^ivr ui* if^i« . «,n tJirpart of the organism. "I In* Ltik of vit*unm iinist |44iiiH fi-i%rcaused some mri of diHtttriutirt* in fit** 4tnt1t1.1I irMtiomv win* Jidemands exceptional activity ftwm thr |#ittni4iv 1**1 v **tidthe adrenals, and thus lrach to t h n r Iiyj^riicijiliy 41 •myrate we can imagine m* «tln*r i4xp)4n;ittr«ti Hut mr kmmnothing of the part playtttl in tlw matfrr t*y thr |fitmt*iryinternal secretion, although the phemunrtu drwr i !^4 t i M l I m ^investigation. In the next rhajitrr, u b m wr i nmr t*i ^Iu4ythe growth-complettin, we «li»)l Irarn that thr pittitf4iy »**lyforms an internal .secretion WHOM; dUxU M^ HI many rr«{*Tt*similar to those of complcttin B# and whtin* functton maypossibly be to increase the activity of the intttti.il rc»*i*ir4tio»

\. b

!<< 4

til

i %n I<\«

H I ?

i t.*

n

. i !

\ .if

1 itJi

i i

i «•

i n

t

!i

* A

!• %\v

. f,\

I# t ;

' 4! '

iHH ^

ill

,n / .1

# a * * 1

a 4 M 4 # 4

a t t l l t t * ' *

lit- ,irt«

n*it

pi-t..M

l..,

un,3-at.til i

I to

M ^ o i * i * c ) i . v x n ; i < i n s

f»t th« t i M 1* 1 } * i ! i i j i } * « * a u >• !h« a t t t w

HMt \ ' t I ' i i J **< I v i t h « f i t i i f i t \ t h a t \ M kn«*vv *i h f t l r

i o m < t ! i H * tu 1 u f j ! -,• ! h f l u p i f n a t a i v h * " K i n t « i a t t o i i

f u I h n < v**i W * a s n i l un« • i t . u n wh« 111* i th«* i i l i >t.nif «*

m tl,< « n f « i i i 1M|* i f t i n | * j t U ! t . f t i \ I m 4 \ i f h r f*%*

p i J i o ' 1 • . M i l p<> » « t i n i h ' l i U t . t l t t l l

\ V kt***\S U4*3l * I ! «sB i * \ t h . i t f it h i»f th» ' t \ \ n

111* f ) i«<l J*l« !u« « % W» H *!' h**** ! t i f t »n» r i

\t *\ \u<\ n n , 1 4 * 4 j i* M I # ,ni»t f i«* in t i n

Ji|« t i t * ' t 11* t U i t . t t f l * <[ * i l i f * l i M l l I l . i l I* U J I I I \Ur i l l «*.*»**

TA-i 4i i t <*!* i<i< i t t v t l i* h\j«* fftMphv *»f Hi* a<ltnul» i iMtuty•tli*< i fh* i t i ^ l a l i t ttti«i* t . fh** * <»»i« x «»f th«" f i l i a l int imtM

1***1 f*i mf* r I f i i t ,in m*it»!*«i fu t t ru tum of ad iu i . thn taj*l f«i* tn hrnl**i$ Mt^ ,i»ri M I I 1 * 1 ' ix | t ! , i ! ! i * thr tnui«t«ni4 in i , i v s nf i^jlyii^ftirtt i* •!•» UAU»w<* th*t!itit umittg t«* ftp* *'tttts t \ r Mipplv *4 . i i tnt tahn tin* stttali

h ,%t<* Mr*»nj;lv *t»titMM« f|# ttttd that hv th*' <«msi*-

H.irr *w ' I n , h'.w« v u , i** i t i t i r l out I I M I # whi l 4 I IM tnittt.M turn*»{ th<* *ut«n«t]< * f,nt*«**l t*v 4«lt* I M I I I I «!««•*. t t i f l f i t l U,u\ to anui'i< i * *»f pr» ut« in Iftf* AtU'tt* #, tn tit** «trtr nul l <•* th f i i t fl\#"»iUj<J in tli* * »|*tl! it i« % fti** pr« >»ur**

!»*' tu hm*l« r th*' on * t i#{ ri(rl«*ttta. Mr>f iovu, it h.n h i * nprovtd t)i4l in i ^ h n u i n f i * thf* M«#ml }*?* tit** tra t l i n than tn« r« * •<!, u that u r tn«4 .* \\n\t< tin*c*f a v.isotttnfof p.»t< i Hut th«* fall tn »itti*tMl p i ^su t i * thu*to rrUix-ittuii «4 th** ,trf"M<«l« * t» ,itt*iif|«*fl hv an tmr«aN«*rI

*tf<'4 f4Vr»UUttJi tMn«ttci4ttr»U flftrl tit** f MtlM^IM'ttt*$ii^ M«< ar i t ' tm has fh«r«"for<\ ((^tmally wi th*

drawn hn hyp i t h * siv *>»'<

^1* f i$i coiner l«? ami t lu t \ u w # u h u h i% cc i tamly

146 VITAMINS

better founded. He assumes that the internal secretion ofthe adrenals is, like that of all other glands reduced by adeficiency of vitamin. The hypertrophy is to be explainedas an outcome of the at tempts of the adrenal to keep up t h esupply of adrenalin, a substance essential to life. The vitaminsrequisite for this are obtained by the liquidation of materialfrom other glands of less vital importance. Ultimately, ofcourse, the supply of vitamin from these sources is exhausted,and then no more adrenalin can be produced notwithstandingthe hypertrophy of the adrenals.

The hypothesis is strongly supported by th<* behaviourof the body temperature in beriberi and experimental poly-neuritis. The temperature falls, though very slowly, and th i smay be interpreted as a sign of the reduced formation ofadrenalin. Suddenly, just before the end, the temperaturefalls by as much as 3 0 C , and death thereupon ensues. Innormal circumstances, the body makes an effective responseto a fall in temperature by the increased formation of adrenalin,and we may therefore infer that the sudden fall in temperatureat the close of the illness is due to a failure in the formationof adrenalin. In conformity with this theory we fmel t ha t ,whereas during the general course of the disease the adrenalincontent of the adrenals is found to be normal, or even somewhatincreased, x°v>, **?7, "15 when the collapse of temperature occursjust before death there is a sudden decline in the adrenalincontent of the adrenals.

/ . The Energetics of (he muscular System.

We have now come to what may perhaps be regarded asthe most important chapter in the pathology of polyneuritiH,to the question of the energetics of the muscular system. I thas long been known that there is a gradual fall in temperaturein polyneuritis, and D u t c h e r w has recently provided experi-mental confirmation of the fact. Raimono,*?8 too, showed in1916 that the respiratory quotient slowly declines, ultimatelyreaching a level which is barely half the normal. This observa-tion has been confirmed by Tanji.745 In conformity therewith,study of isolated muscle has shown a marked falling ofi Inthe internal respiration of the tissues. Abderhaiden, lx$$whose observations show that extracts rich in vi tamin

FORMS OF POLYNEURITIS 147

promptly restore tissue respiration to the normal, is of opinionthat the substances he terms nutramins act after the mannerof co-enzymes, inducing conditions which direct tissue respira-tion and the other activities of the cells into normal channels.Freudenberg and Gyorgy 12Sl have also been able to show tha tnumerous vegetable extracts, and also codliver oil, linseedoil, and cream, must contain substances able to increase therespiratory activities of animal cells.

I t is, however, necessary to note tha t the previouslydescribed behaviour of the muscular tissue is by no meanspeculiarly characteristic of polyneuritis. Abderhalden andSchmidt I3°^ have detected a like decline in the energy oftissue respiration in all diseases attended with muscularatrophy, the change taking place only in the wasted muscles,and being discernible only when these are examined quitefresh. If the experiment was not made until after the musclehad been kept for from nine to twelve hours, it could not beshown tha t vitamin had any influence on tissue respiration

Even if Abderhalden's observations are accurate (andthere is no reason to question them), the causal relationshipsmay be entirely different in the various diseases. We mayassume, for example, tha t in consequence of a febrile disorderthe catalase content of the tissues has been used up, and tha tthereby a weakening of the muscles has ensued, leading toatrophic changes in these organs. Naturally in such casestissue respiration will be rendered more active as soon ascatalase is produced once more thanks to the effect of vitamin.We might, on the other hand, accept the prevailing view tha tthe nerve lesions are primary, and that the muscular a t rophyis a secondary change. But in tha t case it would be difficultto see why tissue respiration should become less active aslong as there is an adequate supply of blood, for the pr imarynerve disorder could not easily affect the catalase content ofthe muscles. The conditions are different if we assume themuscular degeneration to be a primary lesion dependent uponthe absence of the co-enzyme vitamin. In tha t case, i t isnatural that the activity of tissue respiration should graduallydecline in proportion as the co-enzyme disappears from themuscles, although the catalase content of these may beunaffected, and the catalase is ready to be restored to activity

K{8 VITAMINS

as soon as vitamin is supplied. Hut even this th*M\ <i'^not touch the root of the matter. The H ' M M H I I ^ <«f 1 JJLIIWIIand Huishoff-Pol, and ah*> those of Dutch* r,:f . '"» IM\<' b (AIIthat in polymmritis the catalasc* nmt<-nt <»1 tin* tun * 3* iby no means unalferted, but rajiidK fit clings nifihMftlvfalling to barely half the normal D u n l i n ' s u»»ik4 and ** j*««5ally that done by hint in collaboration with ( uH.it/, * hishown that the; administration of vitamin irsimi , th*influence of catalasr, not btrausr (as Abd«ih.iM*n A »UWcatalase already present in the nni^lrs is ,i<tiv»itt<! |.\ Ui*vitamin, but because umler the inihumr ni tin- \itat34iii >«new formation of the absent r.it.il.tse taki j»h««'

g. Differences between Polyncuritis and K!(tnjih>ri MiV .

There is no doubt a resrmblanrr in th«* tnnthtioji *,{ tb<muscular system in beribui and tA'pmin^nf.i! }***htj«as compared with that in othei di^eaM \ l<%idm^ t«* nn.»^ $More especially, the energetics of tin* b*«ly aie *KH*Kin beriberi and poiyneuiitis to what obtain us *iinj»l«- IA%\Ation. There are, however, impoiUnt 4itl«i**ri**' l«tttf<n tb*-economics of the maintenance of br»tblv htMt in ^JUJJ4« f *%\Ation and in avitanrino^Ls, ii'sjwrtiv<'lv. •*'• x%v l«-»« $*«•»» t b r

admirable studies of Novaro.«**<*• " K | |S* Jh«# niij^irt.ifi* «• MIthe matter jttstifa»s it^ detailed diHcti^ioji, In t**#tIt «.r< ,,three periods can be ciistinguisheil: an itntial **t,4^, \%h»<l$lasts one or two days in starvation, but «i f*»rfinals! ut m**trin avitaminosis; then romes a long iiitnnir«li4l^ %l,ir«*, tin*is succeeded in both cases by a biief final *4ajj«' * ntiintutttn*in death.

In simple starvation (in pigeon^) the daily Jo*s of %%*i$*hiduring the initial stage ranges from 4 % to 7 % pri ditiit 4

in the intermediate stage, the ki.ss «loi^ not eicu*ril i */(, <#r3 % daily; in the final stage, it ri^rn onrc rncin* tn th*- s,««<*level as in the initial .stage. Both in the iniiMl and in th»- HIMJstage, the daily loss of heat is considerably MrrMl«r than $11the intermediate stage. At first the 1**1 v t<*nt}^ratiifr i**unaffected, then a gradual decline* s^ts in, and tit thr f$n*ilstage there is a sudden fall We m% then, that the till mtemperature does not run purallrl with th«- !««* of ||#Mt t tbr-temperature may be almost normal even wbtn the Jt^n r#|

FORMS OF POLYNEURITIS 149

heat is from 50 % to 60 % above normal. If follows thatduring the initial stage the production of heat must be con-siderably greater than normal, but that a decline in heatproduction must gradually set in ; ultimately the heat produc-tion falls off so much that it is barely possible to keep thebody temperature high enough for the maintenance of life,until at last the balance between production and loss is sogreatly disturbed as to induce the catastrophic fall intemperature tha t immediately precedes the fatal issue.

In the avitaminoses, however, the temperature and theloss of heat remain normal for a time. The body-weightgradually declines, the decline becoming rapid after a while,in conjunction with a commencing failure to absorb nutriment.The weight falls off far more rapidly than in simple starvation,and subsides to a much lower level. The loss of heat is muchreduced during the intermediate stage, until after three or fourdays the loss amounts to only about half the normal ; thence-forward the loss continues at this rate even in the final stage.The temperature, which (in pigeons) is normally 42-2° C ,sinks rather rapidly to 41 ° at the outset of the intermediatestage, but thereafter the decline is slow, so that a t the endof the intermediate stage it is still as high as 400. When thefinal stage sets in, the temperature falls rapidly to about370, when death ensues. I t follows that at the outset of theintermediate stage the production of heat must be consider-able ; thenceforward, heat production must slowly declineand in contradistinction to what happens during starvationit must permanently be less than normal. Moreover, thecollapse in temperature at the close does not depend (as instarvation) upon increased loss of heat, but upon a furthersudden fall in, or perhaps an absolute arrest of, heat production.

When the experimental animal is put upon an adequatediet in time to save its life, the return to normal occurs inmuch the same way after prolonged starvation and afteravitaminosis. I t is true that after starvation the return ofappetite is gradual, whereas when vitamin is given to ananimal suffering from experimental polyneuritis, the creaturebecomes ravenous almost immediately. Still, the differencesoon disappears, so tha t after a few days the quanti ty offood taken is in both cases about 50 % above normal. Not

I 5 o VITAMINS

until after the normal body-weight has born rnittainnl «lw*the taking of food become normal in amount. Wli»n th rchange for the better is made in the d i n , tin* b«*lv u«Ji:l»lincreases rapidly by from 10 % to 2 0 % ; tin n it f*JiMi»r»stationary for a while; thereafter a slow ami M.mt-tth.ttirregular increase proceed* until the normal wnjjlit 1 i«-jMin« 4The loss of heat also increases, though it remains b* •* *»»**5 % less than normal after starvation, and <io"M 1* *'• th.mnormal after a vitamin-free diet. Then the* loss **f l i n tgradually rises, and rises somewhat more quickly than thebody-weight, so that, by the time the normal body-w« i$;!it !*•*<•

IV

AVXTAMINOSIS. ~— STARVATION.I. Body weight HI. lU*\y trm|*t*tntn*r

II. Heat loss. IV. Heat protlmttMi

been regained, the loss of heat may \m as much its tt% %above normal. Thereafter it gradually sinks to tin* norm*!.During the first twenty-four hours of recovery, thi* \wn\ytemperature rises to about 41^, the ri.se being sslower, until in four or five days the pigeon's normalture of 42 • 20 is regained. Thus the heat production istively small during recuperation ; the food that isis mainly transformed into the tissue that replaces w!i*4fbeen lost, and is not used to any considerable extent for thesupply of heat energy. Not until the bodily condition ha*become normal once more is an excess of heat productionpossible upon a food consumption that still remains executive

FORMS OF POLYNEITRITIS 151

ft»r a time, vi that an increased loss of heat is now manifest,Wlf i i the apj»*-tjt«- i* i»nrr more nannal , tin* food consumption•IK«J Iti'iuuj' n<«imal, and heat production .sinks to the«»i4?najy 1* vrl.

U P - n j i v i s in tlur fijKiuf give a graphic representation ofth«* ihtmiv, in avuaiuim^is aiul starvation respectively. Thett\a\rv mu*t note that , just as in flu: rase of geographicalrehrf mntuur*, the witn-al rl**in«*nt in the curves is greatlyex.ij*tf«'ratrd m <*<»utp.trison with the horizontal I'lrmont, forwrit* th«* v n t i f a l «*lnnt*nt r r p n s m t e d in <l\u\ proportionwttinn thv hnri/ont.il ;>pa«« availal^h* in stic:h a figure, tlicv iTt i r4 Kf,i<l,tti"fi vvotilti hv hardly notiftsihlr. Tin* coursec»f th«- Wright ntrvv \u(h(*i*s to show that in herihert wr rannotMiiiplv Int ron r rn i fd with mainutrit ton drpitndrnt upon anill l i a U n m l dii*t, hut that then* must h« larking in thts foodv*mt* rnnstttti**nt which normally r<*tictcr.s its full utilisationp r ,J!I!I*, whr r ras in starvation tlirtv is a Minplt; combuntion*»i th r liody mat«*nal without th r jHtssihility of any nubstitutc ;ttiat in why thi* rnrvt* in bi^ihcri is far less s twply graded for^ tim«*. until ttit* htn\y\ own supply of tlw requisite materialis :ill t*#nHiiintcl, w h t r r t t p m a *terper gradation in shown.InwparaWv rnnmrti*d with thin in h<*at prnduction. In»t;irvatirin« thf l>f>rly must m i r t all its need* out of i ts ownMifManrr. sinri* thr htMting material thus available consistsmistily of protein, and **in<:e protein rannot b€ adequatelytit 1I1 wt | f«r ;il! th«* purjKisis of the tmdy, them mmt be muchwnsta^r m thin prneetis, and the combustion of the wastematerials 1*M»IS tn an inrreuHt^l h<*at (Mrochiction. But as soonan the fuH tn the Inwly run* short, the heat production suddenlyt!<xlim*H. fatltnis far Iwhiw normal. In polyneuritm, the condi-tions are revet*«t!, IIi*ri% there in a supply of mere fuel,mud dtittng the inituil staRe this fuel in utilised in a fairlytinrmal fanhton ; but n% s*ion as the specific peculiarity of theAmu%i\ dmiini^hfd farulty of titilbation, comes into play,heat production falls off in proportion to thin tautened facultyfor utilisation —very rapidly* at first, unti l the body hasarenmmodated itwif to rircum*itancesf and then more slowly;until at tart 21 complete incapacity for utilising the food setsin# and heat production suddenly falln to a minimum,

The obverse of heat production is heat loss. I n starvation

152 VITAMINS

states the latter is always increased. At first the increaseis due to increased heat production ; subsequently heat lossstill remains above normal, although heat production has nowfallen below normal; finally, just before death, there is arenewed sudden rise in heat loss. In avitaminosis, heat lossruns a very different course. At first, like heat production,heat loss remains normal; then, when heat production isreduced, heat loss exhibits a sudden decline; and thence-forward it remains unchanged at a low level.

The body temperature depends upon the relationshipbetween heat production and heat loss. In starvation states,heat production is, as we have seen, increased in the r initialstages ; but since heat loss is likewise increased, the tempera-ture remains normal for a considerable period. Not untilheat production is greatly reduced, so that it is no longersufficient to compensate heat loss, does the body temperatureundergo a gradual decline ; in the final stage, when heat lossis very rapid and heat production has ceased, there is acollapse in the body temperature. In the avitaminoses,likewise, the temperature remains normal, here for the reasonthat at first heat production and heat loss are both unaffected.Subsequently, when heat production falls off, there is amarked regulative decline in heat loss, but the compensationis excessive, and a rather rapid fall in temperature results.In the final stage, when heat production ceases and heatloss continues, a sudden and fatal fall in temperature ensues.

The differences between the behaviour of the animalorganism in starvation states and in the avitaminoses, respec-tively, is manifestly due in part to differences in the adrenalinproduction. At the outset of the starvation period, heatproduction is excessive, and the body temperature musttherefore be regulated by a dilatation of the bloodvessels topermit increased heat loss, this involving no exceptionaldemand for adrenalin. Subsequently, when heat productiondeclines, the normal tendency of the body is to react byincreased production of adrenalin, in order to promote vascularcontraction and thereby reduce heat loss. By this time,however, the adrenals have been so much injured by thestarvation that the adrenalin production is inadequate. Thetemperature therefore falls, and the fall is more extensive in

FORMS OF POLYNEURITIS 153

proportion as the adrenal inadequacy is greater—until atlast a critical collapse of temperature ensues.

In the avitaminoses, also, adrenalin production is obviouslysoon impaired, this resulting in a sudden fall of body tempera-ture. However, as Bierry, Portier, and Randoin IX97 haveshown, the body uses its last reserves of vitamin (perhapssecured by the liquidation of material from other glands) tomaintain to the utmost the activity of the adrenals. Thelatter undergo hypertrophy in consequence of the increaseddemand made on their energies, but do not succeed in producingmore adrenalin than is requisite to maintain the body tempera-ture at . the lower level to which it has now fallen. Ultimatelythe adrenals can no longer function. Perhaps there is nolonger anywhere in the body vitamin-containing materialavailable for liquidation. Another possibility is tha t heatproduction has become quite insufficient. Anyhow, a criticaland fatal fall of temperature now ensues.

7. EARLIER ATTEMPTS AT EXPLANATION.

These facts have additional implications, which willperhaps enable us to gain a more intimate understanding ofthe essential nature of the disease and of the way in whichit comes into being. But before I turn to my own specula-tions concerning these problems, I must give an account ofthe views published by other observers anent the significanceand the functions of the vitamins.

First let us consider the theories of Portier and his collabo-rators. They hold that the three stages of the disease aremainly determined by the vitamin provision of the body andits influence on adrenalin production. In the initial stageithe organism still possesses a store of vitamin adequate tosupply the needs of all the glands. In the second st&ge, thevitamin content of the organism is no longer adequate, an<tthe adrenalin production is falling off, but the latter troubleis more than compensated by the hypertrophy of the adrenals"|so t ha t in this stage the body actually contains an increasedpercentage of adrenalin. Thanks to the increase in thefadrenalin content and the resulting persistently high tensionof the vascular walls, there ultimately results the frequentlyobserved sclerosis of the finest capillaries. In the third stage,

154 VITAMIN

adrrnahn produ*ti»»n i«.i« nitttth U*T< i *J«f:f r< tcatastrophic fall *»f l*»i\ f* x- j • x *• .2* * 5 « *h i - \*This explanation, a \ ir *.t in tl.< * * • 3 *,* ^ +allowance f«»r th» « h u v an *}« f «« ' f * aignor* H the inatn * au tl < i i * I 1 ^ " J M \hauifly th*f attojiL\ *m<l »!«* * i»« J *% 4*5 t < 5 3 %\tn*ivun* %v -.tt 111 I ntthntn 1* t * 5#f I ! 2 >* ' ^J1*^*

U* a iJJMf J P .n ! , iin tf

i ]

the* throry may M*JU tu »t <<unf ^ r tj « < *» , *5in j ^ Ua*« i t j ^ *L 1'*•? it

* th.it it * niii 4 \* * j 5r t *it working; hvp»fb«* 1**

vttsimtns II,IH l«'i*n mMr l»v lla*i J*t "f *5 1 -4 fthntr al trrnativf livj^4}i«-«^ Hi ft 1 ^ ' *« u i

thr ^laiul** p.itttMpatMv» in t**r

*Ih«* *f»**ml ^ n r ^ ti^ti 1 ft 4! !;•«- \4 fi«*inpart#*kr r4 thf nature *4 f*nntnt i . a*vl }** >%\*c it, .t'the prorrvM*s %A intriiii^ti.itv in^t il#* Ii in 11^ thtt 1nat ivr 1% that the \it.unmH 111*1 l*c 4r»^nt««l f * U*^ I tof horifttifu^, ** thatarc k rk ing . !i.*ussldo licit takr *!<% vrry **# ^w*l '** |»t« j * * w l * t!

y pmerely removi* thr f|iif vttr>m i«* aany answer. If IH tridtihitaUv t in t tl#< ^ l%u«l* n**by an adequate dir t , htit tlun 4**^ ntit rnj t a f l i4O* 4 p^t*iv«r*tpifton IH tnakh'd to lly within 4 i*^v tu»Mi« «4 thr ^ItnifiMttof vitamin, The w o r n ! hvp*thr \ i i 11 r u n tr». ti^lj jutthe firtt, and pr rhapi th*- thit«l hv|Mifhr%$% n m \rcane# for (apart from thr fact t l u t the m«nrlwniMit t»laction, and a im ttn* format^n,, nature . nn4 fnnrtt««ti$nc »lthe hormones, are #tilt a v a l ^ l W*k * netth<t *4 th^w* In 1^1 hiN*^telli m anything regarding th r |4n«r ^hrr<* tl»r v i tamsnttake dflfact or concerning their ni«>dc o< a<t$on.

FORMS OF POLYNEURITIS 155

while the hypotheses might explain either the symptoms ofvitamin deficiency or else the positive effects of vitamins,they cannot explain both of these.

I t is not possible to speak much more favourably of theassumption of Abderhalden,1255 who believes that the vita-mins, functioning as co-enzymes, must create conditionswhereby tissue restoration and other cell processes aredirected into normal channels. For although this theoryindicates a point of attack and conveys some ideas regardingthe mode of action, we have no evidence that catalase needsa co-enzyme to activate it. Nor does Abderhalden's theoryexplain why, in this disease, an insufficiency of catalase isformed in the muscles, or why, perhaps, catalase is not formedthere at all.

By far the most notable attempt to explain the mode ofaction of the vitamins is that made by Schaumann,73» 9°» x*2»X57» *73* 177, 219, **6,3™ and by Schaumann in conjunction withAbderhalden.8o3 As long ago as 1904, Durham 44 showed thatthe excretion of phosphates is greatly diminished in beriberi.Schaumann was the first to point out that polished rice isvery poor in phosphates as compared with unhulled or partiallyhulled rice. In the course of his further researches he foundthat poorness in phosphates was characteristic of all thenutrients inducing beriberi or experimental polyneuritis, andhe was therefore inclined for a time to regard a deficiency ofphosphates as the effective cause of the disease. Otherinvestigators, such as Fraser and Stanton,108 Aron and Hocson/1

etc., made similar observations. But it became apparent,especially in the course of Schaumann's own work, that theaddition of inorganic phosphates to a pathogenic diet hadno good effect whatever, and Schaumann was therefore com-pelled to modify his theory that a deficiency of organicphosphorus compounds was of primary importance.

These were the days when lecithin therapy was still highlyfavoured; although the discovery of phytin had furnishedlecithin with a powerful rival. In view of the scantiness ofthe chemical information possessed by most medical men, i twas not surprising that people should have believed themselvesto have discovered in these mixed-organic compounds thelong and arduously sought organic phosphorus compounds.

156 VITAMINS

But Schaumann's attempts with phytin and lecithin were noless fruitless than those with better defined i»ii<^j>hoxuscompounds. Only nucleinic acid, and especially th*1 formderived from yeast, gave positive resul ts though tht- rfirrtof these substances was far less powerful than that of extractof rice bran. When it was now discovered that Funk's vitamin**were in fact devoid of phosphorus, Schaumann had to tetmnh'lhis hypothesis again, and ho assumed that th«# vitaminsplayed a part in intermediate phosphoius metubnh*in, fum>tioning as a kind of phosphatasts. This seemed all tht? moreplausible seeing that Schaumann's own comprehensive sf mitrsof metabolism as well as those of other investigator •**«:, ru.had shown beyond dispute tha t in polynemiiir ciiNoidrrs the*phosphorus balance is strongly negative despite the m l u r t dexcretion. I t has subsequently appeared, however, that,even when Funk's vitamin is administered, and the jumvr ofvoluntary movement is restored, the phosphorus balanceremains negative, and this observation puts the la.st explanationout of court. But besides Schaumann (who not b»irjf* amedical man, had to be guided in medical matter*, by theopinions of the faculty), all the leading mediral atithoregarded the nervous paralysis an the primary lMoreover, in the nervous system and in the glands tlwu* *ouWbe detected, not only an atrophic degeneration, but alsu adisturbance of the phosphorus metabnlism whirh it W4*natural to regard as the cause of the* failure of nervous innt*tioning- From 1912 onwards, therefore, Srhaumann inrhnrtlto regard the role of the vitamins in intermediate phusptiMru**metabolism as mainly one of activation. He thnef*#re MI|{-gested for these substances the name: of M activators'* fe^tsubsequently withdrew the suggestion in di'fi*rr*ncc to thepriority of the name vitamin.

Tschirsch *o°4 was doubtless influenced by ScliaumamTftresearches in formulating the hypothesis tha t th*? ammt cifberiberi must be the incapacity of the body, in thr ubvnceof vitamins, to effect the cyclojxnesiH that is requisite fc#r theformation of the nucleoproteins. He thus regards the* vttamttiHas ring-closing ferments, without whose aid the food cannotbe utilised for the upbuilding of nuclwiprotcin*. Ajmrtfrom the fact that this theory does not provide &ny explanation

FORMS OF POLYNEURITIS 157

of the almost instantaneous restoration of mobility whichr n s u r s when animals suffering from experimental polyneuritisan* closed with vitamin, it cannot be taken as proved thatt he human organism is incompetent to effect cyclopoiesis,and that human beings would simply starve to death if themres sa ry iing compounds were not provided ready-made intheir food. Tins a t tempt at explanation must, likewise, berejected.

It is worth mentioning that in 1916 VoegtlinSS* endeav-oured to explain the action of vitamins on the theory thatthey served to neutralise the toxins resulting from an excessof rarhphyrirates in the food and the consequent intestinalfermentation. Inasmuch as Voegtlin's own work contributedpowerfully to promote a better knowledge of the mode ofact ion of the vitamins, there can be no doubt that thisauthor i ty spontaneously recognised the untcnability of hishyjw»th<*sis for we find no further mention of it in hissubsequent writings.

8. SUMMARY.

f am not a medical practitioner, and the independentviews I shall put forward in this section are therefore advocatedwi th all reserve. In my opinion, however, there are certainfar ts which may guide us in our search for the causes ofpolyneuritie disorders. I have repeatedly insisted that theni'rvtt degenerations cannot be the primary causes of theparalyses. For, first of all, the latter occur in cases where onpost-mortem examination we can detect no nerve lesions.Secondly, even in the worst cases, the nerve degeneration isnever complete, seeing that some fibres always remain ingood condition. Thirdly, the restoration of mobility is analmost instantaneous affair, so that there is absolutely not ime for the recovery of a damaged nerve. Finally, we learnfrom anatomical evidence that the general improvement isspredy, whereas nerve regeneration in the best event requiresmonths . (Cf. Vedder and Clark,**8 and Schaumann 3«>.) Fort h e same reasons, it is impossible to regard muscular degenera-t ion or atrophy as the primary cause of the symptoms. Theinstantaneous restoration of the mobility of a degeneratedmuscle is as unthinkable as the instantaneous restorationof the conductivity of a degenerated nerve ; and we have

158 VITAMINS

learned that a definite interval must, in fact, elapse beforethe muscular system is fully restored to the normal.

It is therefore necessary to assume that, degenerative changesnotwithstanding, the possibility of functioning is preservedshould it be possible, either to remove an inhibition, or elseto supply some substance that is lacking. An obvious assumptionis that the vitamins are indispensable stimuli. I t has beenshown in the foregoing that similar effects to those producedby vitamins can to some extent be produced by well-knownorganic bases, although the influence of these is not lasting.An electric current, however, has similar effects, and we arecertainly not entitled to contend that the absence of ranimalelectricity is a cause of the paralyses, or that animal elec-tricity is produced by vitamins. Similar effects are not alwaysdue to identical causes. In no science is the validity of thisprinciple more conspicuous than in physiology.

Matters will perhaps be cleared up by a consideration ofthe general determinants of muscular movement. Thismovement is a manifestation of energy, and presupposes theprior existence of that energy. Now the motive power of theanimal organism is combustion, and in animal life we cannotconceive any manifestation of energy in the absence ofcombustion. The formation of lactic acid and carbonic acid,products of combustion, during muscular movement, showsthat oxidation is an essential determinant of such movement.If, therefore, we inhibit the combustion, no movement cantake place even though the nerves and muscles are intact—unless energy be supplied from without, as for instance inthe form of electricity.

In polyneuritic disorders, the combustion in the musclesis, as we have repeatedly learned, reduced. This defectivecombustion has been experimentally shown to be mainlydue to the lack of a sufficiency of catalase. Experiment haslikewise proved that the catalase content and therewith thetissue respiration, i.e. the possibility of combustion, is restoredby the supply of vitamin. Finally, there is experimentalevidence that what happens in the muscles in polyneuritiswhen vitamin is supplied is, not so much that already existentcatalase is activated by the vitamin, but rather that theprovision of vitamin actually increases the catalase content of

FORMS O F POLYNEURITIS 159

the muscles. In a word, the vitamin must lead to the newf o r m a t i o n of catalase.

T h i s , then, is the core of my theory. Under the influenceof v i t a m i n , the catalase content is kept a t the requisite level.We* m u s t still leave open the problem whether the vitaminsplay a n act ive part in the building up of catalase as necessaryc o n s t i t u e n t s of that substance, or whether they are to ber e g a r d e d as directly operative catalase-forming ferments, orw h e t h e r (as Abderhalden suggests) they represent co-enzymesessen t i a l to the formation of catalase.

T h i s merely provides an explanation of the polyneuriticsyndroxpe . The origin of the atrophy and degeneration of themusc le s a n d nerves still remains to be explained, and herewe m u s t invoke the action of a substance of which we as yetk n o w v e r y little, the water-soluble antineuritic complettin,which fo r short I shall now call D.3**8 I t has been shownt h a t F u n k ' s vitamin, the real antineuritic principle, willrel ieve t h e paralytic manifestations, but only these, it doesnot c u r e t he atrophy and degeneration of the muscles and the^ne rves ; and death inevitably ensues in such cases event h o u g h F u n k ' s vitamin be given, unless D be also added to"the d i e t . Numerous a t tempts have been made to describetht* s y m p t o m s as no more than the results of inanition. Thereare , doub t less , plenty of grounds for such an assumption.R e c e n t l y , Simonnet *3« pointed out that both in beriberia n d i n experimental polyneuritis the diet is extremelyi l l -ba lanced , and must certainly be inadequate in more respectst h a n o n e . This authority errs as regards beriberi, for in tha td i sease , though we speak of its origination by a rice diet, wed o n o t usually imply that the patient has taken no food butrice. T h e diet may have been varied, but the mistake hasbeen t h a t the staple article of food has been polished rice.Moreove r , beriberi broke out among the European troops inMesopo tamia , and the diet of these well-fed Englishmenm u s t cer ta in ly have been a varied one. Underfeeding asr e g a r d s protein, fat, inorganic salts in general, and alsoc o m p l e t t i n s A and C, m a y therefore be excluded as a causeof b e r i b e r i , and we must seek another etiological factor. Wem u s t cer ta in ly approve Simonnet's proposal tha t in futuree x p e r i m e n t s a diet should be given that shall be fuUy adequate

160 VITAMINS

except for the absence of the antineuritic factors, for we mayhope in this way to secure clearer and more trustworthyclinical pictures. Hitherto these clinical pictures have oftenbeen confused by intercurrent disorders, especially by mani-festations of the haemorrhagic diathesis and by oedema, sothat the disorder which was the primary object of study hadbeen rendered almost unrecognisable. On the other hand anartificial diet such as Simonnet experimented with (meatthoroughly boiled and pressed, and subsequently extractedwith alcohol and ether ; Osborne's salt mixture ; agar powder ;earthnut oil; butter f a t ; quantitative filter paper [as roughage—see below p. 190]; potato starch; and distilled* water)will, indeed, be vitamin free, but is likely to contain D afterall. In fact, in the diet named, there is D in the agar powder,the fats, and the potato starch. The result was that thisdiet rapidly induced severe paralytic symptoms with tetanicspasms, but the animals' loss of weight was much smallerthan is seen in cases of beriberi, and the typical atrophicform never developed.

I t would have been much better to retain the familiarexperimental diet, supplementing it with specific substances—salts ; A, B, and C ; protein; superheated fat.

Almost at the same date as Simonnet, Karr,I293, ^94 madesimilar experiments which were invalidated by the sameerror and led to the same result. The main fault of Karr 'sexperiments was that , when giving an abundance of B, hedid not realise that he was giving D as well. I t will be neces-sary in such experiments to turn to account the recognitionof the differences between B and D, and thus to plan a dietwhich shall contain a sufficiency of B without any notableadmixture of D. I t is not, however, necessary to troublevery much about the supply of B, since experience shows thatadult experimental animals deprived of B can remain healthyfor a period far longer than that which proves fatal fromatrophy when D is lacking.

Attention has several times been drawn to the fact thatboth in experimental polyneuritis and in beriberi the atrophyis not confined to muscle and nerve; it affects the glandsmarkedly as well, leading to a suppression of the secretions.I t is very significant t ha t the pure neuritis without atrophic

FORMS O F POLYNEURITIS 161

m a n i f e s t a t i o n s experimentally induced by Simonnet andK a r r i n their respective scries of experiments, was not accom-p a n i e d b y any such signs of glandular atrophy or suppressionof s e c r e t i o n . Karr expressly reports that in his experimentala n i m a l s digestion ran a normal course. This is a plain indica-t ion t h a t the absence of I) (which is usually found in associationwi th t h e complettin B) is really responsible for the atrophicm a n i f e s t a t i o n s . Even had Simonnet's and Karr 's researchesbeen o f no other use, we should have to thank them for theclear d e m o n s t r a t i o n they have given that beriberi and experi-m e n t a l polyneuritis are not simple but complex disorders.

When Funk's vitamin is alone lucking, -paralyses withoutatrophy ensue ; when I) is alone lacking, the result is marasmuswith characteristic degenerative manifestations ; when both arelacking, the result is typical beriberi or polyneuritis, in whichthe varying quantities of the respective complettins account forthe more or less marked development of one or other syndrome.

N o w that these relationships have been cleared up, weare f a c e d with a new and important -problem. What is them o d e o f action of the complettin I) ? Since the symptomsc a n a p p e a r on a diet which is in other respects adequate, thisa t r o p h y can hardly be due to a lack of tissue-building constitu-en t s . JBesides, there is a fundamental difference between thea t r o p h y we are now considering and that which ensues in af a m i l i a r form when some well-known constituent is absentfrom t h e diet, or in simple starvation. In D deficiency, weh a v e some th ing more than atrophy due to lack of proteinor e n e r g y , for there is simultaneous degeneration. Event h o u g h we assume tha t in consequence of the want of D theu t i l i s a t i o n of new material and therewith the maintenance oft h e e x i s t i n g tissues are impaired, this hypothesis by no meanssuf f ices to explain the symptoms of degeneration. Asp r e v i o u s l y said, we have no difficulty in conceiving of atrophyw i t h o u t degeneration. But since the two appear in conjunction,t h e r e m u s t be some sort of connexion between them; and inas-m u c h a s atrophy does not per se induce degeneration, we are ledto i n f e r an inverse order of causation, and to suppose tha t thea t r o p h y is the outcome of the degeneration. The organism haslost t h e faculty of maintaining its extant substance, and hast h e r e w i t h lost the faculty of making good the used-up material.

TT

VITAMINS

Life, movement, secretion—in a word, all the manifesta-tions of life—are dependent on the using up of the materialsof the body. We must not imagine that in this process everycell, or every group of cells, throws off part of its molecularstructure, as the dried coats peel off a sprouting onion. Wemust rather assume that reactions occur within the mass sothat the fundamental substance is modified. Nor must wesuppose that these changes occur with equal intensity every-where. According to the nature of the particular vitalmanifestation, the organ or organs chiefly concerned will bevariously modified in their innermost structure. Now theessential feature of life is that whereas the spontaneousdecompositions of the inorganic world are irreparable, thosethat occur in living matter are more or less completelycompensated. In malnutrition, and even in actual starva-,tion, the wastage of the organs primarily essential to life isrepaired by the withdrawal, from less important organs, off

the materials required by the more important ones. If inthe case we are now considering, no such repair takes place, !

if the innermost structural elements do not merely atrophy,but also degenerate, we have to infer that—in contradistinctionwith the state of affairs in malnutrition or simple s t a r v a t i o n -there is a definite lack of something whose presence would renderpossible the immediate restitution of the utilised material.

We are led by these considerations to discern that the funda-mental activity of the complettin D must he a contribution to therestoration of the used-up material. One way of settling thewhole question would be to describe the complettin I) as arestitutive hormone, as the substance which makes repairpossible. But, apart from the fact that we are merely providinga new name instead of giving an explanation, we should haveto account for the remarkable fact, unparalleled in the vitalprocesses of the organism, that a hormone indispensable tothe individual is, by this supposition, not manufactured bythat individual but has to be introduced from without. Forjust as little as vitamin, can D be synthetised in the animalbody.W36 The best proof of this is tha t the xniUc of motherssuffering from latent beriberi is so lacking in these substance*that the infants fall ill sooner than the mothers, (On theother hand, such a synthesis is within the competence, notonly of the higher plants, but also of the schizomycetes and

FORMS OF POLYNEURITIS 163

the y e a s t s For instance, the intestinal microorganisms caneffect such a synthesis. Consequently, as Portier andR a n d o i n xo63 have shown, the faeces of animals sufferingfrom polyncur i t i s contains so large a quantity of vitamin tha ti t w i l l suffice to cure the animal if suitably administered.)

M o r e detailed knowledge of these processes is veryd i f f i c u l t t o acquire, for we arc concerned with the mosti n t i m a t e reactions of life, which have hitherto been completelyi g n o r e d . In the matter of nutrition and repair, modernp h y s i o l o g i s t s , and above all Jacques Loeb, have done a greatdeal o f work, but their labours have by no means sufficed toc lea r xx$> the difficulties. The main reason for their failure ist h a t t h e members of this physiological school are completelyu n d e r t h e spell of a physical chemistry. Their studies aret h e r e f o r e restricted to two special fields; the effect of theions o n the cells; and the reaction of the living colloidals u b s t a n c e of the cell upon other colloids. Obviously suchr e s e a r c h e s will not unlock all the secrets of the matter, as hasi n d e e d been proved once more by Carrers at tempts to inducea n i m a l tissues to grow outside the body. For Carrel foundt h a t s u c h growth would only take place in natural serum,in t h e na tu ra l fluids of the body.

M o r e o v e r , the process of assimilation whereby the cellb u i l d s u p the constituents of the food into its own substance,a n d t h e utilisation of this substance for the purposes of life,can b e explained neither in the terms of ionic reactions norin t h e terms of colloidal chemistry. Both these fields ofr e s e a r c h have contributed much towards the elucidation oft h e b o d i l y processes, but only a purely chemical science canm a k e s u c h processes comprehensible. Here we find our-s e l v e s i n unexplored country, lacking the guidance of evenone e s t a b l i s h e d fact.

T h e explanation of the matters we are considering encoun-te rs a d d i t i o n a l difficulties owing to the entire inadequacy ofo u r a n a t o m i c a l and physiological knowledge for this purpose.I t a p p e a r s to be a fact tha t to some extent the breaking up,r e m o v a l , and rendering innocuous of the products of vitalr e a c t i o n s is effected by the blood through oxidation, but thiss t a t e m e n t sums up all tha t we know of the matter. I t isu n c e r t a i n whether the nutrition of the tissues is achievedb y t h e blood or by the lymph, (I think there are grounds

3 6 4 VITAMINS

for giving the preference to the lymph, although the participa-tion of the blood can by no means be excluded.) Ourknowledge of this process is all the more inadequate inasmuchas the ultimate course of the finest blood capillaries and lymphcapillaries is still unknown to us. Our ignorance makes itvery difficult to study these reactions, and physiologicalscience has not yet ventured to approach this fundamentalprohlem.

For example, we do not know where the transformationof the albuminous tissue "builders into the body's own sub-stance takes place, and the probability is that there are nospecial organs for this function. I t is unquestionable thatnot merely every species of animals, but also within eachanimal every organ, has its own peculiar kind of protein ;and it seems unlikely that primarily there should come intoexistence some sort of standard protein which the individualcells can then metamorphose into their own protein. Thiswould be doing the work twice over, and would render thedigestive process superfluous. Far more likely is i t tha tthe cells themselves build up their own varieties of proteinout of the tissue-building constituents of the food, and thetheory that that is how the process takes place has beenreinforced by Carrel's success in growing the living tissues.But here we encounter a new contradiction, for this growthwas effected in serums which contained, a t most, traces ofamino-acids in addition to serum albumin. We must nottherefore reject the supposition that the cells of the organshave at least some power of transforming an extraneousprotein into their own protein. The rapid disappearance ofthe amino-acids from the fluids of the body after meals iscontributory evidence in favour of this view.

If we are in search of explanations of the inner mechanismof the action of the water-soluble ajitineuritic D, the.foregoingtheory will seem quite inadequate. There are three factsto bear in mind: the cause of the atrophy or degenerationis, the lack of a certain substance; this substance is notsynthetisable in the animal organism, and it is renderedinactive by heating, especially under pressure in a moistmedium; finally, the locality where the substance takes4effect must be in the cells.

Starting from the last consideration, we can think of

FORMS OF POLYNEURITIS 165

three ways in which the absence of a substance might hinderthe rebuilding of tissue. First we might assume that theproper mode of action of the substance in the cell is to promotethe synthesis of the cell-substance itself. Secondly we mightassume that when the cell is intact and the food is otherwiseadequate, the function, of the missing substance is to promotethe linldng of the nutrients to the cell-substance. The thirdpossibility is tha t through the absence of the substance underconsideration, the mixture of nutrients has somehow beenrendered inadequate.

To "begin with, let us consider the first of these assumptions.The sjsnthesis of the cell-substance proper is achieved in theanimal organism with very modest adjuvants—so modesttha t the process might seem hardly possible. During synthesisin the plant cell, hydration plays a leading part, the additionof molecules of water, or the elimination of groups of atomsby the action of hydrogen. In the organism of higher animals,not a single instance of the kind has been proved to occur.(There are cases of so-called reduction, as when aldehydesare transformed into alcohols with unsatisfied affinities.But these reactions depend upon the addition of water to acompound and its subsequent detachment; they do notdepend upon the action of hydrogen.) Nor is there known inthe organism of higher animals any instance of the synthesisof carbon chains. Animals obviously lack the power oflinking a carbon atom to a carbon atom, of effecting whatchemists term a pure condensation. The only condensationsthe animal organism can achieve are those which take theform of couplings in which carbon is linked to nitrogen oroxygen with the splitting off of ammonia or water, or some-times with the splitting ofi of salts—the process wherebyethers, esters, or peptids are formed. On the other hand,the organism is also competent t o break up existing compoundsby the introduction of a water group or an ammonia groupof elements. By these simple reactions, b y the alternatingaddition or subtration of water or ammonia, the most complexproteins can be built up by the animal organism, providedtha t the necessary carbon chains and amines are suppliedin the food.

In the light of the first hypothesis, therefore, we supposethe mode of action of D in the animal cell to be such tha t

i66 VITAMINS

this substance, behaving as an enzyme, either promotescombination or else hydrolytic or aminolytic decomposition.We may, of course, suppose that there is an indirect actionlike that of a co-enzyme ; but inasmuch as the basic conceptionis still purely hypothetical, this supposition would involvea superfluous complication. Apart from that, there are goodgrounds for questioning the accuracy of the whole assumption.First of all, it is hardly conceivable that the animal cell (whichfundamentally resembles the plant cell and has come to differfrom the latter only through adaptation to a different environ-ment) should be so dependent upon this environment andupon all the alien factors outside the organism as^ to beincompetent for the spontaneous fulfilment of the very func-tions by which as a living being it is distinguished from theinorganic world—so that it is compelled to secure theabsolutely indispensable enzyme from external sources. Anadditional reason against any such assumption is that whenthe food supply is completely cut off, the function we areconsidering can still be carried out, so that in the organs ofthe most vital necessity the processes of assimilation continueeven though the organism as a whole is foredoomed to deathfrom a lack of the intake of energy. Doubtless the lastconsideration has no demonstrative force, seeing that deathfrom starvation is a comparatively rapid affair, whereas inpolyneuritic disorders the lack of certain substances has totake effect for a long time before the illness begins. There is,however, a third reason for rejecting the enzyme theory asvery improbable, for all the organic enzymes hitherto knownare comparatively thermolabile. The complettin D, in adry medium, can resist an hour's heating a t 1200 C, anexposure which destroys all known organic enzymes.

The second possibility is that there is lacking some sortof intermediate link which, if present, would couple thesubstances derived from the food to the cell-substance proper.If the suggestion is that we have to do here with somethinglike the amboceptors of serology, i t may be incontinentlyrejected. For in that case we should have to assume tha tthe different substances in the cell all constitute a chemicalaggregate which is as it were eaten away at one end by thevital reactions, its integrity being then restored by the linkingon of substances derived from the food. But the supposition

FORMS OF POLYNEURITIS 167

is certainly tenable if we presume tha t some intermediarygroup may be missing from the food, a group which if presentwould have enabled the substances in the food to be builtup in to an aggregate identical with that of the cell-substanceitself. If tha t is the way the second supposition is to beinterpreted, we can pass on immediately to the third theory,according to which the missing link is itself a constituent ofthe food.

The vitally essential requirements of the food would appearto be as follows. I t must contain a sufficiency of carbonchains of definite but varying lengths. In part these mustbe amjjiised, and in part must contain certain rings. Further ,these substances must be sufficiently far reduced. Finally,there must be an adequate supply of groups with unsatisfiedaffinities, so tha t the necessary couplings may be possible.The first four requisites are deducible from the proved factst h a t the organism of higher animals is incompetent tosynthetise carbon chains or to effect ring closure (except inso far as this is possible by the simple formation of lactone);t h a t only in the rarest cases can it achieve aminisation ; andt h a t i t is quite incompetent to effect hydration. The fifthrequisite is obvious, seeing that the new substance requiredby t h e organism has to be built up by couplings.

T o decide where in this instance the defect may lie, wemus t further make allowance for the fact that although thesubstance in question is generally believed to be fairly thermo-stable it is certainly damaged by prolonged heating. Underthe conditions tha t obtain we may exclude the possibility ofa decomposition of a carbon compound by over-heating, ort h e decomposition of the possible ring-closing substances.I t is, however, perfectly conceivable that sensitive aminescan be saponified by heat, especially in the presence of water,the amine group being replaced by a hydroxyl g roup ; andAbderhalden's researches have shown that the hydroxidescannot replace the amines of the food—cannot be re-aminised.This possibility must, therefore, be borne in mind ; b u t thetheory is rather improbable, seeing tha t the amines hithertoknown to be present in the food and in our organism are notvery sensitive to heat. Among the synthetic amines, thereare certainly many in which, owing to peculiar structuralconditions, the amine group is readily detachable, but no

i6ft VITAMIN'S

such substances are known amotiK thr natural auun*the possibility must not hr .th<t'lutf*I\ <)i.fiu «•!, ha it j%known that thtr vvatrr in wlmh nit •*! ha* b* » n l*<•?!*•! t *-*iit,tin %more ammonia than \va, cl« in«»n tiahlf m tlit ni«at lln»question arises, however, vihefh*1* flu j-httinj* %*H i* i*«»tcomparable to that which <»mir. a*, a j*m«Jv |*h\ i«'l<»i*ir.ilaccompaniment of digestion vwthout anv b t .mnr **n nufitti**ii4

as when earbamides are tianvfonin t\ mitt th«f t^n* |**»ii4ii?rammonium compounch.

There is a srroiul gnmp of fompur.tfivi Iv nn t.i}»J* -ulistances in natural fooris, ruinptemn what i* kn^^n 4* th«sulphhydril group. Hir^ hsti-m * ^ ha% l i iaun »itt*nij«*ji tr*these. In the hydmlysU of pioftsn. in th«" la!»<44i^n ucfind as the primary rrjuvM-ntativr of th«* ^nlj4jni < <*}s«)«*uh«isrystin» which is an anhvdnd** *4 th« -ulphh\ <li.it* *s ^rm,In our discussion of the bilingual \,tln^ i4 tl*«- j4 ' i!»m, w<*learned that these Mib^tainf% a?i* alrohn*Jv « *tifi*l to Iilr,(lystin is a very unstable suh*4aiK<% \W ai r *iitiU<d to 4%*kwhether cystein, tcK», mav not IM* of #*r* t! i!!4}*< if m»r fr-r thrupbuilding rif proteins, sn ing thai if 1. rv* n m<*tr \m laM**than the anhydride. A j«>v-»ibl«« <*bj«Mioti t*t MKJJ 4 %i*w IHthat a sulphur free diel i , ruid«*ti>i .»«l«qtu*« !*v tti«- addift^nof cystin ; hut th«i'e is nn u%i^on why v%< Ji^nSd 11*4that in the body this anhydride may tak** 113* \% it* r .m*Jdecomposition into oxy ;tinim> pmjaot^* , 1*} ,%n4so that the really art ivr hnriv J* thr siiljihlivdf.a*" Atrate, we know that in th*- ftn#cl# rystm r.m U** tr|«J^«-«l bycystein ; and it is rertaiu that wh« 11 < ith« r r4 th** \til^t.in« r iis heated in the pn>wnn* of wati-r, th»- ^iljtliut r. *j«iii *4f,Thereby, both cystin and <\st«t!i are * l*\ t*#ii%Iv i^?i*l^ti^lvaluelcsH for n u t n t t w purjK^i^, iitasmurh a% vui|thh\dr.ittoncannot be effeited in tin* anifn<i! IKKIV. HI*- l ^ t llwl t t indecompositiem is not m n H y po^siJJr m th r Mr<"Uiir4aiirrs weare considering, but df^-n actually u n i t , t% prnvr<l by thefact that when tins of prrvrvi*! mmt nrr #ipn*4 4 tmlydefinite odour of MilphiuvUi't! hy«koi»*-ii JH t*ften |^rcr|ttit»ir,During the war, the ^rnhvat iou of tun ic ! m«%tt w.i** %<* r»$th-lessly conducted th;it rumphmil-* of thi< si«t«ll l^ tucommon.

Besides the Milphur group, wi* h.ivi* r«Mw,n l*t n |that the food contains other group* of MslMancc* %ifli

FORMS OF POLYNEURITIS 169

readily modifiable composition (for instance, bodies with analdehyde-like structure), bu t our knowledge of these is toovague to justify definite statements concerning them. Weare, however, certain that the proteins, and especially thenucleoproteins, contain thermolabile mixed-organic com-pounds. Thus it is supposed that part, at least, of the phos-phoric acid in the nucleoproteins must be present in theform of metaphosphoric-acid compounds; and on prolongedboiling in water these, even when combined with bases toform metaphosphates, are more or less rapidly transformedinto orthophosphates. This may be taken as a partialconfirmation of Schaumann's views concerning the indispensa-bility of certain organic phosphorus compounds, for the animalorganism is unquestionably competent to change the lowerstages of oxidation of phosphorus, such as metaphosphatesand pyrophosphates, into orthophosphates, but cannot effecta reversal of the process.

Simple prolonged heating of foodstuffs, especially at ahigh temperature or under pressure, may therefore be pre-sumed capable of bringing about any one of three changescompetent to render inadequate an otherwise adequatenutrient, because the animal organism cannot reverse thetransformation. These are : (1) the disaminisation of vitallyimportant amine compounds ; (2) the decomposition of similarsulphur compounds (and perhaps of substances belonging toother unstable groups) ; (3) the metamorphosis of meta-phosphates and pyrophosphates into orthophosphates. Reac-tions (1) and (2) will make it impossible for the foodstuffs tobe assimilated to form cell-substance, for the unstable groupsin the food mixture will have been destroyed. In the caseof reaction (3) the unfavourable effect is twofold: in thefirst place the food will have been deprived of the metaphos-phoric and pyrophosphoric radicals, which are essential tonutrition; and secondly the aid to the process of couplingwhich would have been furnished by these phosphorusderivatives, will now be lacking.

In the second chapter we learned that the lower-gradeamino-acids are apparently of no vital importance, seeing thatthey can be formed within the body out of higher compoundsby ample oxidation. When, therefore, we think of disaminisa-tion as a pathogenic influence, it is only the amino-acids of

x7o VITAMINS

high molecular weight that come into the question, hutare present solely in ccmipnrativrlv • mall quantities in j»i«*j»hv-lactic or curative !)• containing extra* t%. Hut tin*f ** is i*vnlrnrrtelling against the theory that dis.unimvation hv h t . i tmr isof much importance in this connexion. I'm «r*t.imr, in thesufferers from beriberi in Mesopotamia, l\n- m«at rationshad been lavish. If, theirfor«\ we arr to *« rar*l lh< I n k ofcertain axnino-acids as the essential cati.r of th** m.ilmitutf<*n,we mast suppose that tht* meat must h a w IIM » rjmtrtegrated by the process of sterilisation a f,u m«*«- thordisintegration than can br efiertetl in tin* cht tnual KuWduring artificial hydrolysi*. I therrf*»rr con.i«l«r tti^tdisaminisatum factor may be dismissed fi»*m th* k

Again, complete c!isinte|;niti«m of the vutphutis hardly conceivable evrn in uhra-st*nh ^ t in* at, s*» thatthis assumption ha» little probability m if* favour.

With regard to the* third hyjjothevt*. «n tin* *A\m han4#

the experiments of Franris and TrowlindK**111 .u*<l tliosr *ifTrowbridge and Stanh-y'M have shown that *Um nir.if IHboiled even for a comparatively brief period, tir^rttmare transformed into inorganic I consider that $11with the appearance of btrihrri m jn*rsnn% on athis is the factor we have rliiHly to tcm^idrf atrounial i l r furthe causation of the atrophy and dr^rtirtafi**n of mn^l^$

nerves, and glandular tissues. 'Ihtis %%-v toinr back t» tin*early view of Schaumann, that th«* laik n\ oicompoundn mast play a leading \\A\\ \n tlirneuritic disorders. If dosage with ** or^tnir pln*%}iti*iir%failed to do any good, thi.n was !)tr»iiM* thr ph«*^j4i4triiwere not those: vitally essential |4iosph;iti^ normallyin the food. The phosphorus tompounth n ^ 4 in th* jments have for the most part \m*n mm*&»m%mu c*tm§*r#ymKsimple ester-like combination?! of ordinaryacid, not containing the metaphtiHphatr* mid pthat are indispensable to the animal orgnnium.

This must not be interpreted as an amerlkm thut rm»ta-phosphates or pyrophosphatc*s would be effective m nuch,for it is quite possible that what counts m theif tticido ofcombination in organic matter. No dmabt whtti we tiydfulyitorganic substances containing phmphmi» v we find thesephosphates; but it does not follow that the animal

FORMS OF POLYNEURITIS 171

is competent to produce them. We know, indeed, that whendigestive enzyme acts on the nucleoproteins, phosphoric acidis split off provided the action is continued long enough;however, the latest investigations point to the conclusionthat in natural digestion no such complete splitting off takesplace, bu t that larger and more complex compounds areabsorbed from the alimentary canal.

Until further study has supplied us with better lights, weare entitled to accept as a working hypothesis that in theseillnesses the repair of tissue waste has been rendered impossibleby the lack of certain organic phosphorus compounds in thefood. JThis lack is in some cases due to the direct removalof certain ingredients, as in the " polishing " of rice, or inthe boiling of food and the subsequent throwing away of thewater used for the purpose ; and in some cases it is due tothe destruction of thermolabile substances by excessive orunduly prolonged heating. Hence the atrophic changes inthe affected organs, for continued work without the replace-ment of the used-up material must in the long run infalliblycause degeneration. An additional factor is undoubtedlythe lack of catalase, owing to which the catabolic changesmust run an abnormal course. A further source of troubleis tha t the medium in which tissue change has to be effectedis rendered unfavourable, on the one hand by the presenceof these products of abnormal catabolism, and on the otherhand by a deficiency of inorganic constituents.

An objection which may be put forward against the fore-going theory is tha t in starvation states, when the supplyof the same substances is likewise absent, though atrophyensues, there is no degeneration. We must, however, rememberthat in starvation the course is far more rapid, and that inpolyneuritic disorders the period of incubation is oftenconsiderably longer than is requisite in starvation for a fatalresult. I t has, moreover, been proved that during starva-tion the most vital organs are nourished at the expense ofthe others, in order that the former may be kept suppliedwith adequate nutriment. In starvation, therefore, the lessimportant organs atrophy, and will at most exhibit degenera-tive phenomena towards the very last, whereas during theprolonged incubation of polyneuritis there is plenty of timefor degeneration to ensue

(HAI 1 IKK I IVh

T H E CONDITIONS OF G K O W I I !

1. iMKCJlirc 1<»KV.

THK old schematisation of tlu* tlm*r\ *4 nwtuti<«n, with i nundue stressing of thr iinpojt»uur <4 thr tij>j H *4 }*tntvmand energy, wrought m m h hititn, ,ind IJ*»\\ !<«?«• IA.I th« h.tiinso manifest as in tin* domain of the f*tdm?: *4 * InMur* wutt*«rit to recall how autliontjt s in tht-trtj«'4 iiinmniii it** nut*.* «-4demand for food drp^mit-nt up«n i;r«*wth, \ i i t r * Miuuit tuestimate childicn's mr*i fr i ntitinu* nt •« j'f««j^*i!if4>.iJ tosize ami wdght . S i tntiriumml WA% \h*> .*j»j»|j»*iti**n *f tin*principle tfiat we an* i«\illv <*ntitUcl t«# \\on<J*r th.#t ihrnutritive requirementh of infant in .intr- dunni: ill** fiistweeks (?f life weir not MIJ*JIUM it !** t*«* *** itKf*#! t<* *; f

M ^4 ffn:reqtiirements of thf adult, A KMHI t iunv \« . t i . afc* { {Mout that growth nff«*^»ati!y thttunih .t f.«r it^4*- *ir|ivrover# and that for thi** reason tin* initntivf ir<juir*iiifitfHduring growth nnr.t !«• mrtirn|Mr«iMy #*#« »4t« r %h*n t h ^ ^ c#ladults. I showed fmtlicr tha0 tli4iik% tu thr* }*r-d4nliywhich ignored this nrnMtK ration, thr a tills n} all tin*investigations rcgauiing tlu* mitntt^n <4 th«* |K«|m!atiun ofthe United States (invt^tigattons wliirh IMV«- nrA ttunymillions of dollars) h a w k r n Wfirthlrss. Diningdecade there has h r m a change for thr l#H!*i\first, it would sc*em, only on tht* c4h« r side r4 thr AtLintir,Thus in K)20 M, A. Brown *«** dc^rtared that thr nuttilivcrrequirements of the growing crganisti) had htthf*ttogreatly undt'restimatc*d. I)i%pitr theory, in pr#tf tict%children are not thriving, thosf* n<s\*mh%UU$ for thrir car**always ready to try and enforce improvement by angant supply of nutriment, chiefly in the farm of

T H E CONDITIONS OF GROWTH 173

but sometirfoes in tha t of carbohydrate or fat. Witness theinnumerable proprietary preparations for the feeding ofchildren with which the market has been flooded for decades.The very multiplicity of these preparations is the best proofthat most of them are ineffective, and tha t those whorecommend and use them are on the wrong road. The troubleis that, as Terrien I2 lS phrases it, far too much faith has beenput in the so-called dietetic test. The mere fact tha t by anexcessive supply of nutriment it is possible to cause an increasein weight, by no means signifies that the development of thegrowing organism has necessarily been redirected into theright channels. To justify a conviction tha t such an improve-ment has occurred, we must ascertain by detailed and accurateobservation t h a t absorption and excretion are properlyrelated each to the other, and that the increase in weightis not due to a morbid deposit of fat or a morbid retentionof water in the tissues.

Here prolonged observation is requisite, and the medicalpractitioner is seldom able to undertake anything of thekind. The patient is brought to see the doctor once or twiceat the ordinary hours of consultation, and tha t is alL Theremay or may not be improvement. Unless improvement isimmediate and obvious, the parents are apt to growimpatient and to consult another physician, who will havea different method. While each adviser, guided simply bythe increase in weight, may be convinced that his prescriptionshave been helpful, in the unfortunate little patient gravedisorders of health are gradually developing, and thespecialist whose advice is ultimately sought may be unableto ascertain their direct cause.

The disastrous results of the present methods of childfeeding in our large towns should suffice to convince anyonetha t the period of observation should be much longer thanis now customary. If we are to draw sound conclusions asto the value of any particular diet, it is not enough tha t weshould be able to show tha t one individual apparently thrivesupon it. Osborne ia24 is right in maintaining tha t in manycases the effects of errors of nutrition do not become notice-able for three or four generations, and the assertion has beenendorsed by numerous other investigators. How many

i 7 4 VITAMINS

instances of so-called degeneration, of anatomical hindrances tochildbirth, of incapacity for procreation, conception, lactation,etc., are referable to dietetic errors in earlier generations !

' it is obvious that the life of the individual human beingis too short to enable any one of us to make a sufficiency ofobservations in the case of the human young. On the otherhand, we must carefully avoid a premature application tohuman conditions of the results of experiments on animals.But when it is possible to trace a close parallelism in theserespects between human beings and the lower animals, thetransference of conclusions is justified. Above all, it is justi-fied when the same causes produce the same effectsrin themost diverse classes of animals, as in birds, rodents, ruminants,omnivora, and camivora, and when it is possible to prove thatin a comparatively short time these causes produce the sameeffects in human beings. Then we may apply to humandietetics what we have learned from experiments on animals.We saw in the last chapter how valuable this method hasbeen in the case of the polyneuritic disorders, notwithstandingthe fact that we may be disinclined to regard the experimentalpolyneuritis of birds as perfectly identical with beriberi inhuman beings. From this outlook, the investigations of thelast decade, and especially those of very recent years,although they have been carried out on animals, are of over-whelming importance in their application to dietetics in thecase of adult human beings no less than in that of children^

2. IMPORTANCE OF PROTEIN.

In the second chapter a detailed account of the importanceof protein was given. Most of the experiments upon whichthat account was based were made and confirmed upon growingorganisms, and as far as generalities are concerned it willsuffice to refer to what has previously been said. All thatI need add here is that, thanks to the dominant tendency tooverestimate the importance of protein, substances shown bya cursory chemical examination to contain a considerablepercentage of crude protein are often esteemed far morehighly than their merits warrant. Let me recall the wartimeattempts in Germany to supply a richly albuminous nutrientderived from yeast. To make " nutritive y e a s t " (as it was

T H E CONDITIONS OF GROWTH 175

pompously styled) money was spent by the million, largequantities of sugar being wasted in the process—thoughsugar was exceedingly scarce and was urgently required forthe feeding of the people. This sugar was literally thrownaway, for physiological experiments on nutrition have provedthat the crude protein which " nutritive y e a s t " certainlydoes contain in very large quantities, partly consists of freeamino-acids and is partly of low biological value, so thatordinary potato protein is a far better nutrient. (Cf. Funk,Lyle, and McCaskey.567) In brief experiments on humanbeings, Wintz 53<> did, indeed, find that when the rest of theproteinmin the diet wees high-grade, as much as 30 to 40 % ofthe protein could be given in the form of yeast protein andeffectively utilised ; b u t the exhaustive researches of Hawk,Smith, and Holder 87* have shown that in ordinary circum-stances the amount of " nutritive y e a s t " protein in the dietcannot usefully exceed from 10 to 30 %. Moreover, the useof yeast protein is restricted by the fact that not more thaaone or two grammes can be tolerated. When as much asfour grammes are given, diarrhoea sets in.

I n like manner the crude protein of the pulses thatordinarily ripen in Germany is far too highly esteemed. Inm y own experiments,3*9, 6r4, 785 the protein requirement ofan adult human being could not be tolerably well suppliedb y a smaller quanti ty than ten pounds of haricot beans daily.McCollum, Simmonds, and Pitz,6*5 and McCollum, Simmonds,a n d Parsons,6^ report that the protein of ripe peas, beans,a n d lupines is quite inadequate to maintain growth.

I t is essential to remember that many varieties of proteint h a t are able in an emergency to keep an adult going (thewhole rye grain, for instance 896), are incompetent to providefor normal reproduction, or to ensure a proper secretion ofmilk. Consequently, when the diet is ill-balanced, and whenthese sorts of protein predominate, the offspring may sufferseriously even though the parents may seem to be doing wellon such a diet.

The following varieties of protein are known to be quiteinadequate to maintain growth: the aggregate protein frombeans, peas, and lupines 645> «9*> *96; phaseolin,335. 423 legumin,a n d vignin (which are able at most to keep up the body-

176 YITAMINS

weight22^ 423) ; rye,*96 wheat,5*5, 579, $*, 801, 896 barley,74°, 896oats,598,635, 896 rice,8?6 maize,8^ soy beans,^6 ze in^s , 4*3 conglu-tin,235* 423 hordein (can only maintain weight 225, 42-3), gliadin(can only maintain weight 3-5, 246,423. 55°), carrots,784 gela-tin,2^* 423 bananas.775,968

It is true that in certain parts of the before-mentionednutrients we find varieties of protein which are able tofunction as efficient growth-factors, such as edestin ("badly ! 541)excelsin,225» 423 maize glutelin,235, 423 and the protein of thewheat germ.5°7 But these adequate proteins are not presentin quantities sufficient to supply the needs of the growingorganism. Since, however, the various proteins differogreatlyin composition, it is sometimes possible to induce satisfactorygrowth by a mixture of foodstuffs each of which, is separatelyinadequate. It is important that the ingredients of such amixture should not belong to the same class of foodstuffs,for within any one class the proteins will usually he found tohave the same general composition, and therefore to presentidentical defects. The leading defect, as a role, is aninsufficiency of certain ring compounds—such, ainino-acidsas tryptophan or tryosin, and above all an insufficiency oflysin and cystin. Hence the cereals, which are poorly fur-nished with, lysin, are per se quite inadequate, b u t can berendered adequate as growth-factors by the addition ofgelatin, since this substance contains 6 % of lysin. 598» 6a5

There is not a very large choice of really adequatenutrients. Among seeds, the only ones we know t o beadequate are cotton seeds, for cottonseed meal, when nottoo finely sifted, suffices to maintain growth.4939» 5*4, 55°> 654Furthermore, cottonseed globulin is adequate, as is alsopumpMnseed globulin.^, 423 Potato protein,567 too, isadequate; my own experiments showed this protein to havean unexpectedly high biological value. Eggs ,3^ 745 and alsothe separate proteins they contain (ovalbxirnin and vitellin),are adequate growth-factors.*35> 4*3 In m y own experiments,the adequate protein of milk was found to resemble t h eadequate protein of egg in possessing the very highest biologicalvalue.7^5 As regards lactalbumin, its high biological valuehas also been proved by experiments on animals,235, 4*3, 54*although Chick and Dalydl have shown I378 tha t b y stipple-

T H E CONDITIONS OF GROWTH i 7 7

menting lactalbumin with small quantities of cystin a furtherincrement of growth can be secured. Opinions differ asregards casein. In experiments of only 30 days' duration,Osborne and Mendel «5. 423 found that casein could maintainnormal growth in mice ; but subsequently they reportedtha t it was only two-thirds as effective as~ lactalbumin 5#« ;by the addition of small quantities of cystin, casein couldbe rendered as good a growth-factor as lactalbumin. Thismay explain Hopkins' observation,»* that casein was notfully adequate, but could be rendered adequate by supple-menting it with very small quantities of milk—quantities sosmall a3 to increase the amount of dry substance in the foodby only 4 %. Still, we must not reject the possibility thatin Hopkins' experiments the mixture of salts employed maynot have been fully adequate, and that the beneficial effectof the addition of milk may have been due to the salts in themilk rather than to the small quantities of lactalbumin itcontained. Finally, Osborne and Mendel have drawn atten-tion to the fact that what is called " protein-free milk *' reallycontains small quantities of cystin. This may account bothfor the improvement in the efficiency of casein noted in Hopkins*experiments when rnilk was added, and for the great superiorityof natural milk to isolated lactalbumin or casein,

I must not omit to mention the opinion of many investi-gators that, after a certain age, milk is unsuitable as the solesource of protein. Freise1006 agrees with Mattill andConklinIj85 in referring this unsuitability to the fact thatmilk is not a sufficiently concentrated food, and they havesecured far better results when fresh milk has been to a largeextent replaced by dried milk. But these same experimentsreally show that the reputed inadequacy is not due to anydefect in the composition of milk protein, but obviously tothe modified requirements of the adxilt organism in the matterof inorganic constituents.

I t has been shown in the foregoing that inadequate proteinscan sometimes be rendered adequate by supplementing themwith other proteins which are likewise inadequate when usedexclusively. Obviously, then, an inadequate protein can bestill more easily supplemented by an adequate protein. Forinstance, maize may be converted into an adequate growth-

I ? 8 VITAMINS

factor by adding blood 34*, s™ or milk "43; maize gluten, bylactalbumin or cottonseed meal55o; cereals, by gluten, casein,yolk of egg, or milk w ; maize by lactalbumin 6 l 3 ; rice,454or seed protein in general,579 or bananas,775 or cajrots,7*4 etc.,by casein. The amount of the supplementary protein requiredis comparatively small, and Osborne and Mendel ^3 drawspecial attention to the fact that it is far less than would "beneeded if the supplementary protein had to function as thesole source of protein.

In the second chapter we learned tha t the minimalquantities of protein needed to maintain weight have hi therto,as a rule, been overestimated. The statement is lessr applic-able to the period that immediately follows birth, for a t t ha ttime, owing to the demands of growth, comparatively largequantities of protein are required. Still, the differencebetween the minimal amount needed to maintain weight andthe optimal requirement for growth is not very large. McCol-lum and Davis 435 report that in the case of young ra ts forthe maintenance of weight the minimum proportion of milkprotein needed in the food is 3 % ; that, as the proportion ofinilJc protein is increased, growth proceeds more rapidlyuntil the amount of milk protein in the food reaches 8 % ;this is the optimum, for further increments of protein do notadvantage growth in any way. Several years earlier, Osborneand Mendel a25 had come to the same conclusion.

If the quantity of protein is kept near the rniuimuin, orat any rate well below the optimum, an increase in fats orin carbohydrates, even though considerable, does not exercisea favourable influence on growth.^1 This observation con-flicts with the generally received opinion, "but it accordsperfectly with the demands of the law of the minimnrn, Whenthe amount of protein in the diet is reduced, the experimentsof Richardson and Green *54 show that the first effect is t h a tthe rate of growth falls off, and tha t when the protein israhiced to the minimum that will maintain weight, growthis completely arrested. If, now, the amount of protein inthe diet is yet further reduced, loss of weight ensues.

Of course the level of both the minimum and the optimumis mainly determined "by the nature of the protein used asfood. In addition, however, the relationship between the

T H E CONDITIONS OF GROWTH 179

protein and the total supply of energy plays a notable part.8*?Though, as already said, assuming that a definite amount ofprotein is being given, even an immoderate increase in thesupply of energy in the food fails to exert any influence ongrowth, Bierry 833 is right in insisting that a minimal supplyof protein carries with it the need for a minimal supply bothof fat and of carbohydrate.

3. IMPORTANCE OF INORGANIC SUBSTANCES.

Nevertheless, a diet containing adequate amounts ofprotein, fat, and carbohydrate, is still far from being competenteven t a maintain the body-weight, let alone maintain normalgrowth. In Chapter Three the importance of the inorganicconstituents of the food has already been discussed. HereI need merely point out that i t is not enough for the foodsimply to contain inorganic sa l t s ; what is indispensable toan adequate diet is that the supply of inorganic constituents,and the varying quantities of the respective salts, should beduly related to the age of the individual under consideration,to Ms bodily and mental condition, to the nature of the nutri-ment he has hitherto "been receiving, and to the present supplyof food. We have learned with regard to the inorganic ingredi-ents, tha t not merely must there be a sufficient minimumof each, but tha t they are mutually interdependent, so thatthe various minima are not constants (as has hitherto beengenerally assumed "by dietetic experts). The supply of theinorganic constituents of the diet must therefore be adaptedto the supply of the respective organic constituents; andabove all to that of the protein in the diet, for protein containsan excess of sulphur and phosphorus, which in the healthyorganism are oxidised to form the corresponding acids, requiringfor their excretion a suitable supply of "bases in the food.The conditions tha t regulate the bodily requirements in respectof protein axe already complicated enough; but it followstha t the conditions tha t regulate the bodily requirements inrespect of inorganic constituents must be no less intricate.

I t must be remembered, too, that, in the groining organism,metalxrtism is necessarily far more active than in the adultorganism,, and t h a t the increased turnover in the formercreates a fax greater demand for inorganic nutrients. There

!8o VITAMINS

are two substances in particular of which the adult organismhas comparatively little need, whereas in the growing organismthe demand for them is exceedingly active. I refer to i r onand calcium. As far as sucklings are concerned, nature a t t endsliberally to the matter : for at the beginning- of its ear th lypilgrimage the immature being receives an ample provisionof iron from the maternal store; and milk is extraordinarilyrich in calcium salts. But when the sources of milk run d r y ,the prospects of an adequate supply of calcium are great lyrestricted.

It is a good thing, therefore, that , by the very fact ofgrowth, the growing organism is enabled to utilise t h ecalcium salts of the food in a way impossible to adults. T h eadult has to devote a large proportion of the calcium suppliedin the food (and what is said here of calcium, applies on t h ewhole to magnesium as well) to promoting the excretion ofthe excess of phosphoric acid contained in the diet. In t h esuckling, on the other hand, there is an active demand forpurely inorganic phosphoric acid no less than for calcium,seeing that the former is needed as well as the latter for t h ebuilding up of the osseous system. In the adult organism,large quantities of tricalcium phosphate are excreted a sexcess of ballast by the mucous membrane of the large intes-tine, and are eliminated with the faeces ; but in the growingorganism they are built up into the substance of the bones.Here is a characteristic difference between the metabolismsof the respective ages.

In the third chapter we learned that, in respect of inorganicingredients, foodstuffs can be divided into two main groups,respectively containing an excess of bases and an excess ofacids. Apart from the artificialities introduced by civilisationand by its dealings with the cultivated plants, the distinction Isa sharp one and is of fundamental importance. Furthermore,we saw that within each of these main groups the differentclasses of foodstuffs have their own peculiarities. For example,the proteins of most seeds, and especially those of the cereals,are especially characterised by inadequacy due to a lack ofcystin and lysin. In like manner, i t is a common character-istic of seeds, not only to contain an excess of acid, but alsoto exhibit a deficiency of calcium. For lime is almost always

T H E CONDITIONS OF GROWTH 181

present in the soil, so that seeds need not contain any morecalcium than is requisite to provide for the growth "of thefirst rootlet. In growing animal organisms, on the otherhand, the need for calcium is very great. Cereals, consequently,quite apart from the fact that they contain an excess of acid,are about the most unsuitable food we can force upon the growinganimal organism. The best proof of this is that evengraminivorous birds collect insects to nourish their young.The fledglings of the most strictly vegetarian birds arecarnivora!

I am merely repeating here what I have said time andagain gisewhere, but it will be well for me to show how exten-sively recent study of the determinants of growth proves thatwe are concerned with something more solid than ingeniousspeculations of my own. Enough to refer to especially import-ant and characteristic researches. Funk,527 McCollum,Sirnrnonds, and Pitz,6*5 and Hess and TJnger,75<> state thatthe supply of inorganic salts in oats (whether the whole grainor the meal) is inadequate for the upbringing of young animals.Hart, Halpin, and Steenbock655 inform us that wheat cannotmaintain growth unless supplemented with basic sodium andcalcium salts; and according to McCollurn, Sirnrnonds, andPitz,5°7 the germ of the wheat grain is Likewise inadequate asa growth-factor. The latter make the same report regardingrice ; and McCollum and Davis 454 state that rice is deficientin bases. The mineral content of barley is quite insufficientfor the needs of the growing animal organism, and this grainmust be supplemented by a complete mixture of nutritivesalts.740 Various reports are available as concerns the supple-mental need for inorganic salts in animals fed on maize.McCollum, Simmonds, and Pitz,57* Hogan,634 Hart, Halpin,and Steenbock,655 and OsTxoie, Mendel, and Wakeman,1280

all lay stress on the deficiency of calcium in maize, saying thatthere is not even enough to supply the needs of the adultpig ; and Hogan 5^ further insists that , for the promotion ofgrowth, a. maize diet must be supplemented by sodium andchlorine in addition to calcium. McCollum, Simmonds, andParsons,6*1 and Hart and Steenbock,956 make the generalstatement tha t for the maintenance of growth the cerealsmust be supplemented by sodium, calcium, iodine, and perhaps

VITAMINS

chlorine as well; and Hart, and McCollum w expressly declarethat all the cereals contain an excess of acid, and that a cerealdiet therefore requires the addition of inorganic bases.

Cotton seeds are an exception to the general run of seeds,for they contain a protein that is fairly competent to maintaingrowth. Richardson and Green 5*4 found, however, t h a tthese seeds likewise are inadequately furnished with calciumand other bases. According to McCollum, Simrnonds, andParsons,^1 haricot beans are not able to maintain growthunless their protein and complettins are supplemented by theaddition of calcium carbonate and sodium chloride ; andMcCollum, Sinunonds, and Pitz 645 state that the pulses* gener-ally are inadequately supplied with sodium and calcium.McCollum and Davis 431 report that seeds as a class are lackingin inorganic nutrients, and must be supplemented by mixturesof inorganic salts.

Bananas, again, are too poor in calcium to be adequategrowth-factors.775. 780' 980 Roots and tubers are often grea t lydeficient in calcium, and sometimes deficient in sodium.According to McCollum, Sirnmonds, and Parsons,777 this isespecially true of potatoes; and according to Denton a n dKohniann,784 of carrots.

Various authors emphasise the difference, from the nu t r i -tional outlook, between the green parts of plants and t h eseeds. Whereas the seeds contain an excess of acids, t h eleaves contain an excess of bases; and whereas all seeds a r edeficient in calcium and sodium, leaves are often richly suppliedwith these bases. McCollum and Davis 43r have shown intheir experiments that omnivora (such as pigs and rats) fedCHI grain can rear their young provided that the grain isadequately supplemented with green fodder. McColhim,Simmonds, and Pitz,645 even in experiments on birds, supple-ment grain feeding by giving leaves rich in sodium a n dpotassium; and they point out that under natural conditionsthe graminivora do not live exclusively on grain, but ha^vea great liking for young and tender greenstuff—for instance,they nip off and swallow whole the fresh shoots of newlygerminated plants. In view of these facts it is rather remark-able to find McColhiin (McCollum and Davis 440) maintainingthat the alkalinity or acidity of the food has no inflaence o n

T H E CONDITIONS OF GROWTH 183

nutrition. This strange assertion is explicable on the groundthat for the estimation of the base-acid ratio McCollumemployed the obsolete and fallacious method of titration ofash alkalinity. The method will often disclose ash with analkaline reaction in foods which a more accurate analysisshows to contain a marked excess of acid; during the processof conversion to ash, the greater part of the sulphur andchlorine often disappears. This is why McCollum and Mscollaborators, in preparing their artificial mixtures of salts,have paid insufficient attention to the supply of bases, sothat their mixtures are inadequate in that respect. Owingto t h a fact tha t their mixtures do not contain a sufficientexcess of alkali, their successes in the upbringing of younganimals cannot be compared with, those of Osborne and hispupils, who used mixtures of inorganic salts containing amore notable excess of alkalies. Thus a single defect inanalytical technique can introduce the greatest confusioninto the results!

4- IMPORTANCE OF THE METHODS OF PREPAEIKG F O O D .

I t is necessary to insist once more that nutrients maynot only "be primarily inadequate in respect of their contentof inorganic salts ; they may be primarily adequate, butmay be rendered inadequate by the method of preparingthe food. For example, the cereals already have a pooreqxdpment of inorganic sal ts ; if now, in preparing pap forchildren, only the finest sorts of meal be employed, we areusing a substance from which the greater part of the saltshas been discarded, so that such a food may be directlypathogenic. Again, the common practice of throwing awaythe water in which food has been boiled, leads in manyinstances to a dangerous impoverishment in the inorganicconstituents of the diet. (Vide supra, pp. 73, 125, and 171.)Furthermore, measures that might be supposed to have noeffect of this kind, such as the sterilisation of milk, may incertain circumstances bring about important changes inthe mineral content of a foodstuff. We have already learnedt h a t when milk is sterilised by heat, the calcium-magnesium-caibonophosphate it contains (a salt indispensable to theupbuilding of the bones) breaks up into its constituent salts,

154 VITAMINS

and that three of these, namely calcium phosphate, mag-nesium phosphate, and calcium carbonate, are quite insoluble.Not merely does there result an impairment of the physiolo-gical working of the substances in question; but further,as McCollum and Parsons 1300 have shown, a partial coagula-tion of the milk protein ensues during the sterilisation. Thecoagulated portion is precipitated with the salts, and clingsfirmly to the wall of the container. Thus the simple sterili-sation of milk, as for example in a Soxhlet apparatus, leadsto a physiologically important reduction in the bone-formingsalts of the milk.

The author is, therefore, in full accord with Osbqrne,1"*who insists, that the urgent interest and novelty of th& com-plettm problem must not lead us to forget the decisive importanceof tht inorganic salts.

5. THE FAT-SOLUBLE CO:MPLETTIN A.

It has been proved that normal growth cannot be securedby the most sedulous attention to the four great classes offootstufis hitherto recognised. An adequate supply of pro-teins, fats, carbohydrates, and inorganic salts, is far fromsufficing in this respect. The priority here must certainlybe given to G. Lunin,3 who showed as long ago as 1881that substances of a hitherto unknown character, essentialto growth, were apparently present in milk. The state-ment was confirmed in 1912 by F. G. Hopkins.203 Almostsimultaneously, Osborne and Mendel 2~5 drew attention tothe same fact, and investigators generally now became awarethat water-soluble growth-factors must be important ingre-dients of food. As early as 1909, W. Stepp93 recorded thepioneer observation that nutrients which have been extractedwith alcohol and ether cannot maintain life in mice; butthat if the alcoholic extract has been made in the cold, itsreaddition to the nutrients renders them adequate oncemore. In this connection, physiologists were a t first inclinedto think of the lipoids, some of which are soluble in alcohol.

In the following year, however, Osborne and Mendel 3°5showed that the factor under consideration was not universallypresent in fats. For instance, normal growth does not takeplace in animals fed on an artificial diet in which the sole

T H E CONDITIONS OF GROWTH 185

fat is lard or dripping ; but if a little butter be added tothe diet, or if butter be substituted for the lard or dripping,normal growth is resumed. In these experiments it was alsoproved that the fat-soluble growth-factor must be an ingre-dient of those portions of the butter fat that have a com-paratively low melting-point. When the butter was meltedat a moderate temperature and centrifuged, the growth-factor was concentrated in the clear butyric oil. Inasmuchas this butyric oil is practically free from nitrogen and phos-phorus, it was manifest tha t the growth-factor could notbelong to the lipoid class.

Much interest was aroused by this discovery, and numerousinvestigators now attempted to elucidate the nature andmode of action of the complettin A. Since the effects ofthis substance are not confined to the promotion of growth,it will be necessary to devote a special chapter to the fat-soluble complettin A, and for the nonce we need concernourselves only with its function as growth-factor.

The researches of McCollum and Davis, 453,454 and thoseof Drumrnond, 499 and others, speedily showed tha t thiscomplettin A is in fact indispensable to growth. The presenceof the substance in butter was confirmed by McCollum andDavis, also by Aron,44$ and by Langstein and Edelstein.73°,78oCodliver oil, and fish oil generally, contain it in abundance %)6;so does the body-fat of beeves, whereas the storage fat con-tains very little.^34 Among the vegetable oils, linseed o i l 6 ^is extremely poor in this constituent; and olive oil andrape-seed oil 730, 7&>, 896 contain but little. Cocoanut oil, andthe palrnin or vegetable margarine made from it, are veryill-supplied with the growth-factor 7?°» 7%° ; whereas animalmargarine manufactured from oleomargarine or olein con-tains a fair amount, though not nearly so much as realbutter . On the other hand, the stearin residues obtainedby pressure as a by-product in the manufacture of animalmargarine is devoid of the complettin A.424 Seeds containvery little, and are therefore inadequate foods in this respect;millet, hemp seeds, 636» 682» fy* and cotton seeds,534,654 areexceptions. Among the cereals, oatmeal (which has of latebeen so widely recommended as a food for children!) isparticularly poor in A, aad is therefore incompetent to pro-

186 VITAMINS

mote growth.^5. 750 Maize,?68 rice,454,5°7 and bar ley^ 0 arenot much better ; nor is wheat, this statement applying "bothto the whole gTain and to the gercn.5°7> 515 Whereas thecereals in general contain too little A,w some of the pulsesare adequately supplied ; the soy bean is notably rich in thissubstance.^ Bananas have too little 775; so have potatoes.777

The discovery was soon made that the A content of afat is greater in proportion as the fat is of a richer yellowtint. Then it became apparent that this is likewise true ofroot crops; whereas potatoes, which are colourless, containvery little A, carrots, and in especial the more richly colouredvarieties, contain an ample supply. More careful researchesshowed, however, that the association of a high lipochrornecontent with a high A content is merely fortuitous; nutri-ents containing much lipochrome may sometimes containlittle A, and conversely nutrients containing little lipochromemay contain much A. Further investigations disclosed thefact that fat-soluble A may be present in a foodstuff thatcontains no fat at all, or practically none. Green leaves,for instance, which (except for their minimal supply of leaf-wax) are almost devoid of fat, frequently contain consider-able quantities of A—more than most fats contain.

Melianby 1J35 is, indeed, disposed to consider that theimportance of A as a growth-factor is inconsiderable, for inhis experiments, in which dogs were given a diet containingvery little of this complettin, growth seemed to he inde-pendent of the A content of the food. He quotes as con-tributory evidence the experiments of Hess and Unger, inwhich the growth of children fed on dried skim-mili, sugar,cottonseed oil, autolysed yeast, orange juice, and flour, wasperfectly normal—for Melianby holds that this diet waspractically devoid of A. But neither Mellanby's own experi-ments on dogs, nor those of Hess and Unger on children, areconclusive as to the indispensability of A as growth-factor,seeing that the assumption that the complettin A is metwith only in animal fats is absolutely erroneous. Laterinvestigations have shown that skim-milk, and also Osborne'sprotein-free milk, contain notable quantities of A. Eventhe casein of commence manufajCtured from skim-milk, andthe lactose of commerce prepared from whey, often contain A,

T H E CONDITIONS OF GROWTH 187

sometimes in considerable amount. If we further bear inmind that cottonseed oil, autolysed yeast, cereals, and, inespecial, orange juice, all contain a fair proportion of A, weshall readily understand how, in the diets specified by Mel-lanhy, the summation of the small quantities of A in thevarious nutrients can easily have produced a total fullyadequate to maintain normal growth.

Before leaving the complettin A, it will be as well tom a l e perfectly clear that A is not identical with either thelipochromes or the lipoids. The investigations of Palmerand Kempster959> 9s0* 961 have shown that the substancesbelonging to these categories have no effect on growth. Inaddition, we must note that the complettin A exhibits anotable degree of thermostability. I t does not seem to beany the worse for prolonged boiling (in milk), or even forprolonged heating to over 1200 C. (in butter). I t is, how-ever, very sensitive to the oxygen of the air. I ts efficacyis seriously impaired when butter containing it is broughtto a temperature of 100c C. and vigorously stirred; whileif air is forced through the melted butter, the complettin israpidly destroyed.

6. T H E GROWTH-COMPLETTIN WATER-SOLUBLE B.

a. Historical.The part played by the complettin A as a growth-factor

has not yet been fully elucidated, although it is known thatA certainly does function in that capacity. I t is much thesame with the water-soluble growth-factor, the complettin B .True, that the previously quoted observations of Hopkinsand Funk refer mainly to the complettin A ; and Funk'soriginal assumption was that a diet containing both A andvitamin was fully adequate for the maintenance of growth.Bu t this acute observer soon realised that in addition tovitqpnin there must be other water-soluble substances offundamental importance. More especially he learned fromthe experiments he published in 1913 and 1914 that ade-quate growth could not be secured by an artificial diet richin vitamin "unless it also contained the second water-solublegrowth-factor^1*. 3*3, 334, 3^ His researches were soon con-firmed by other investigators, and McCollum and Davis 45& 454

i88 VITAMINS

expressly declared that a special water-soluble growthfactor must be indispensable in addition to Funk's vitaminand the fat-soluble factor A. Dmmmond,499 and at an earlierdate Osborne and Mendel,--5 found that milk containedwater-soluble growth-factor in the absence of which normalgrowth was impossible; and Drumrnond secured similarresults with the lactose of commerce. We may parentheti-cally remark that Funk 3** assumed that this growth-factorhad in the adult organism to be destroyed by some sort ofspecific reaction; he held that the formation of malignanttumours must be due to a failure to effect a sufficientdestruction of the water-soluble growth-complettin In theadult organism. This complettin, he imagined, becomingconcentrated in some part of the body which, for one causeor another, was peculiarly predisposed to such a concentration,gave rise to a crude and uncontrolled proliferation of thetissue cells.

McCollurn and Simmonds661 made interesting andexhaustive researches on growing animals whereby the appli-cability of the law of the minimum to the growth-com-plettins was demonstrated. From these experiments itappeared that when the food contained only A or only B,even in marked excess, the animals speedily perished. EitherA or B might be given in quantities just sufficient to main-tain weight, hut this could not keep the animal alive forlong. It soon became weak and succumbed to prostration.If A or B were given to satisfy the minimal requirement,and the other complettin were provided in excess, weightcould be maintained, but the animal died just as quicklyas if both A and B had been reduced to the minimumrequisite to maintain weight. If both A and B are given inquantities exceeding the minimum requisite to maintainweight, growth now takes place, becoming more active asthe dose is increased up to a certain point. But the opti-mum requisite to promote growth is not very much largerthan the minimum requisite to maintain weight. McCollumand Simmonds believe that i t is easier to keep the animalsin good condition even if very small quantities of A and Bare given, than to keep them in good condition when anyother factor of the diet is seriously reduced.

T H E CONDITIONS OF GROWTH 189

AronI045 showed that extract of carrots contains largequantities of B, but is inadequate as a growth-factor unlesssupplemented with A, which can he best done by addinga high-grade fat. Delf,"^ who found that the expressedjuices of green vegetables are rich in B, proved tha t thesejuices are not adequate growth-factors unless supplementedwith A. She was able to demonstrate that when the dosageof B rises above the minimum, the growth-curve exhibits arapid rise. But the optimal effect is soon attained, andbeyond this point a farther increase in the dosage of B hasno influence on growth. Aron, and also Erich Miiller andother specialists in the diseases of children, observed thatin children that were supposed to be thriving, to supplementthe diet by fresh vegetables, extract of green vegetables,extract of carrots, or extract of bran, could alwaj'S bringabout a further increment of growth. These observationsshow how defective the nutrition of our children must bein contemporary life, even under what appear to be favour-able conditions.

Obviously, experiments of this kind must be subjectedto a very rigid criticism, especially as regards the generalenvironment of the experimental animals. In earlier days,before experience of these matters had been gained, experi-menters were seldom able to breed healthy animals for severalgenerations in succession. As late as 1916, J . C. Drum-moad498 (whose statement was confirmed by noted Germaninvestigators) declared that i t was impossible to bring upchickens properly under laboratory conditions, especiallywhen the birds were fed on sterilised food. The belief gainedground that the activity of t i e intestinal bacterial floramust be essential to the life of the higher animals. Butfurther study of the conditions of life and growth in variousspecies of annuals has shown that this assumption was erro-neous. The ill success of the earlier experiments was mainlydue to a destruction of the complettins in the animal's foodby excessive sterilisation—by overheating. But, apart fromthis question of the food, many of the environing conditionsare of vital importance. The animals must have room tomove about natural ly; the food-containers must "be pro-tected from defilement, and yet must be readily accessible;

igo VITAMINS

there mast be a sufficiency of light and fresh air, etc. Normust psychical influences be neglected; the animals mustenjoy the pleasures of society, and must not be needlesslydisturbed. Merely taking them out of the cages frequently,in order to weigh them, may have an unfavourable effecton the growth-curve. Robertson and Ray483 have paidspecial attention to such matters in experiments on mice,with excellent results.

One factor of great importance is the supply of a suffi-ciency of indigestible material to give bulk to the faeces—material now termed "roughage." Aron44^ drew attentionto this in connection with nutritive experiments one rats ;McCollum and Davis,43* and McCollurn, Simmonds,and Pitz,5°7 in the case of omnivora; and Hart, Miller, andMcCollum,5x5 in the case of pigs and rats. Osborne andMendel,6*3 and Hart, Halpin, and Steenbock,3260 were ableto show that the debility of fowls fed under laboratory con-ditions could be completely cured by giving them a suffi-ciency of roughage. The best material for this purpose,better than charcoal or sand, is a chemically pure filter paper.Considerable quantities of this material are requisi te; ahen needs about two-thirds of a square metre of thick filterpaper every day.

Difficulties arose, at the outset, in preparing" complettin-free proteins, and indeed in the composition of t he diet ingeneral. The first really decisive successes are recorded in apaper by Osborne, Mendel, and Wakeman 1O98 published in1920, when the physical and chemical properties of the com-plettins were fairly well understood. In a subsequent paper3

x33*Osbome and Mendel amplify their reports, mat ing specialreference to the preparation and administration of the indi-vidual complettins; but these prescriptions are less satis-factory than could be wished, for the authors do not drawan adequate distinction between the various water-solublecomplettims.

I t is worth repeating here that , even when the otherenvironing conditions are all that could be desired, thevalidity of the results may be seriously endangered by theuse of too small a number of animals. In this respect, like-wise, Robertson and Ray's experiments on mice 4*4 deserve

T H E CONDITIONS OF GROWTH 191

the closest attention. These observers have recorded theaverage development of mice during the different stages oftheir life. Obviously a knowledge of such details in thecase of experimental animals is of decisive importance inour appraisement of the results.

In conclusion, it is well to note that the tastes acquired"by animals during the natural conditions of existence in thefree state—their instincts, if you like to use the term—helpto safeguard them against mistakes. Osbome and Mendel 739record the observation that rats given a free choice betweentwo food mixtures which appeared to be identical in respectof tas^e and physical qualities in general, instinctively pre-ferred the mixture which was adequate; some of the animalsthat seemed to like a change of diet, and would not at firstconfine themselves to one or the other, concentrated theirattention on the adequate diet as soon as growth began tobe deficient.

i . Occurrence of B.

Whereas the complettin A is not very widely diffused,the complettin B is present in a large number of foodstuffs.The following whole grains and other seeds contain con-siderable amounts : oats,635 maize,578 wheat,579 barley,74*malted grain,7& beans,636 soy beans,65?> *65 earth-mits,68r

pulses generally,^45 cotton seeds.654 Cajori I366 reports tha tto maintain growth in rats, 0*5 gramme of chestnuts, walnuts,or hickory nuts, 2 grammes of pine kernels, hazel nuts, orPara nuts, and nearly 3 grammes of almonds, were requisite.According to McCollum and Simmonds,683 seeds in generalcontain large quantities of B, the husks and the brans beingespecially rich in this substance,448, 730, 7&, 781, 896 which caneasily be extracted therefrom. McCollum, Simmonds, andPitz,5°7 and Osborne and Mendel,873 state that the germscontain eyen more B than the bran or husk ; bu t the cerealsare least favoured in this respect. Bananas, according toSugiura and Benedict,775 and according to Langstein andEdelstein,7&> are so poorly supplied as to be an inadequatefood ; but the insufficiency manifested in these experimentsmay be referable to other causes. Aron 7*x insists that freshfruits contain plenty of B. Plums, pears, and apples,"47axe not conspicuous in this respect; but cocoanut cake *7*

I 9 2 VITAMINS

oranges,n53 and lemons,11*? contain large quantities ; andaccording to Osbome and Mendel orange juice is as effectivein this respect as fresh milk.

All observers are agreed 73°. 780, W in describing cabbageas peculiarly rich in B ; so axe green vegetables in general.:*1

According to Osborne and Mendel,^1 1 gramme of the driedsubstance of lucerne or spinach contains as much B as do2 grammes of wheat, soy beans, eggs, or milk ; white cabbage,clover, and timothy grass are about equal to spinach.According to Steenbock, Gross, and Sell,IO53 and accordingto Osborne and Mendel,10?8 among the last-named, clover isthe richest in B. Lucerne contains nearly as muoh, butthe amount in spinach, tomatoes, cabbage, kohlrabi, carrots,and potatoes, is only half as great, and tha t in beetroots iseven less—all measured in the dried state. The dried sub-stance of 16 cc. of milk has the same efficacy as x grammeof dried spinach. According to Osbome and Mendel,937 con-firmed by Whipple,I287 onions are fairly rich in B . So areturnips, mangel-wurzels, the leaves of the same, and toma-toes, very rich in B 937; and according to Steenbock, Gross,and Sell,9$i in an artificial diet, 15 % of carrots, swedes, orthe rhizomes of Arum macula turn (lords and ladies), willsuffice to maintain normal growth ; when sweet potatoeswere used instead of the carrots, etc., 20 % was requisite;of sugar beet or of mangel-wurzel, even more was needed.Lecoq I07* formulates what he regards as a general rule whenhe says that all the active tissues contain large quantitiesof B, whereas the storage tissues are comparatively ill-sup-plied with this substance. This is in conformity with theobservation that wheatmeal 873 is rather poor in B ; andthat polished rice 454 and the finest cottonseed meal5>4 con-tain so little that they are unable to promote normal growth.It is not surprising that, according to Oslorne and Mendel,?37grass should contain much more B than mature hay con-tains, for the latter is already on the downward path towardsdeath a t the time of reaping". McCoIlum, Simrnonds, andPitz6a5 stress the fact that all natural fodders, which havenot yet "been subjected to artificial methods of preparation,are rich in B. We have seen, however, (and Steenbock, Gross,and Sell s81 are emphatic in asserting) that the quantity of

T H E CONDITIONS OF GROWTH 193

B in any natural nutrient cannot be regarded as a constant,for i t varies according to circumstances.

The lower plants, likewise, are rich in B . Abder-halden 896 has shown that fresh yeast contains large quan-tities ; and Langstein and Edelstein 73°. 780 tell us that t herichness in B is maintained by yeast in the dry state. Paciniand Russel7°3 demonstrated that an extract of typhoidbacilli, and the culture medium in which these organismshad been grown, were rich in B ; this throws a new lightupon the frequently observed fact tha t after typhoid feverin children a rapid increase in stature is ap t t o occur.

Butcher's meat would seem, according to Osborne andMendel,663 t o be very poor in B ; but meat extract is ra thermore literally supplied. Drummond 6 ^ makes the samereport as regards the muscular tissue of stock-fish, herring,and preserved salmon. The aggregate herring seems t obe better supplied, and Drummond supposes tha t the differ-ence is due to a concentration of B in the reproductive a n dother glands. But the same authority reports tha t in mam-mals the testicles, the ovaries, the pituitary body, the thyroid,and the thyrnus, are very badly supplied with B ; and t h a tin rapidly growing tissues, such as those of the foetus a n dof tumours, no B can be found. On the other hand t h epancreas,564 the liver, the heart, and the brain contain an.abundance of water-soluble B.662> 1™

Of exceptional interest, of course, is i t to ascertain t h eB content of milk, the natural food of the growing organism.Both human milk 7Sl and cow's milk 737 appear to be ra therpoor in this growth-complettin. For rats, 16 cc. of milk a rerequisite to secure normal growth; when the allowance w a slimited to 15 c c , a supplement of 0-2 gramme of dried yeastinduced a marked and sudden increase in growth. As faras the promotion of growth is concerned, it does not ma t t e rwhether we give full milk, slrim-milk, or Oshorne's protein-free milk; approximately the same quanti ty of each ofthese is requisite. I n the case of dried milk, the dosagemust be about 50 % higher.737 Be it noted tha t the l as tstatement applies to the dried milk of transatlantic manu-facture, which is much more sensfbly prepared than the Germanbrands. German dried milk probably contains very little B .

194 VITAMINS

Since B, like D and the vitamins, is apt to be carrieddown as a precipitate with other substances, considerablequantities of B are often found in the casein and lactose ofcommerce.499* 579 If, therefore, these substances are beingused in experiments on growth, they must first be carefullypurified.

But the B content of milk, like the B content of othernatural nutrients, is far from being a constant. Theinvestigations of Osborne and Mendel,1^1 Hopkins,I3I4 andothers have shown that the amount of B and also theamount of A in the milk vary according to the season andaccording to the nature of the fodder. The amount islargest during spring and summer, and when the animalsare pastured or are given green fodder; in autumn andwinter, and when the animals are stall-fed or are given dryfodder, the B content falls off.

c. Quantitative Estimation of B.

Williams,9*3 and almost simultaneously Abderhalden andKoehler,95* observed that the growth of yeast is notablystimulated by the addition of extracts " rich in vitamin/'Bachmann I229 and Williams "45 independently proposed,almost at the same date, to make use of this fact for thequantitative determination of the amount of B in variousnutrients and extracts; the method received the endorse-ment of noted investigators,1*0^ "84,1297 ^ a has been modi-fied in several directions for the avoidance of irregularities.Bachmann 958 had himself pointed out that the growth ofdifferent stocks of yeast was very variously affected by suchadditions of vitamin-containing extracts; and Emmet andStockholm I2°3 observed that the reaction was inconstantwhen only one stock of yeast was under observation. More-over, JUuni&re IJ*7 noted that the addition of well-definedorganic or inorganic substances often produced better resultsthan extracts rich in B ; and also that extracts that werecertainly devoid of complettin had, none the less, a powerfuleffect. Quite recently, Fulmer, Nelson, and Sherwood,3^*have fully confirmed Lumi&re's observations ; and McDonaldland McCollum I358 have drawn renewed attention to thefamiliar fact that a vigorous growth of yeast can be secured

T H E CONDITIONS OF GROWTH 195

in nutritive solutions containing little else than inorganicsubstances, and certainly no B. We must assume, there-fore, that the stimulus to the growth of yeast provided byvarious extracts is little, if at all, dependent upon the presenceof B. I t follows tha t the deductions drawn b y variousauthorities,1286' Iz87> ^98, 137* upon the basis of such experi-ments concerning the B content of the most diverse nutrientsand animal organs, are entirely fallacious. Those who wishto ascertain the quantity of B in any nutrient or organ must,therefore, have recourse, as of old, to the tedious and costlymethod of experiment on animals; but the results obtainedby this method are trustworthy.

d. Properties of the Oomplettin B.

The growth-complettin B (which Abderhalden, in defianceof the fact that it contains no nitrogen, speaks of as " nutra-min" ) is, by universal agreement, readily soluble inwater,448, 453, 454, 499, 654, 682, 730, 780, 1076, etc. a n ( j therefore is

completely removed from vegetable food by the customarypractice of throwing away the water in which the vegetableshave been boiled.784 In contradistinction to A, i t appearsto be insoluble in fat 453> 454; but like A it is soluble inalcohol in a moderate degree of c o n c e n t r a t i o n s 1O76 Thelatter statement appears to conflict with a report by Loeband Northrop 569 to the effect that the efficacy of the sub-stance as a growth-factor is " permanently i n j u r e d " byalcohol. The growth-promoting substances are insoluble inacetone, ether, and benzin ™76; but strangely enough can,according to McCollum and Simmonds,67<> be redissolved outof the alcoholic extract by benzin or by acetone after pre-cipitation with dextrin and subsequent drying. No lessstrange is the observation of Robertson and Ray, I296 tha tthe growth-factor can be extracted from brain substanceby acetone, and it seems questionable whether what reallyhappens in this instance may not be merely the removal ofan admixture of A by fat-solvents.

When we at tempt to study the properties of the com-plettin B, we have to reckon with a very disturbing factor,namely that most authorities have failed to draw any dis-tinction between B and D, this often leading to serious con-

196 VITAMINS

tradictions. For example, nearly all subsequent investi-gators have confirmed the observation of McCollum andSimmonds 67° tha t this complettin is unaffected by hydro-chloric acid, nitric acid, and sulphuric acid. But these sametwo American authorities, in the same paper, describe thecomplettin B as sensitive to alkalies—a statement which con-flicts with the reports of most other observers. Accordingto Byfield, Daniels, and Loughlin,1^ the growth-factor inoranges will resist, not merely alkalinisation, but subsequentboiling for five minutes ; while Whipple ia87 assures us thatin cabbage i t will tolerate boiling for several hours, even ina solution containing o-i % of hydrochloric acid or e cor-responding amount of sodium bicarbonate. In like manner,a considerable heating of animal substances such as meat,during which ammonia is always formed, has no influenceupon the water-soluble growth-complettin.

Speaking generally, this complettin, in contradistinctionto complettin D, seems to be fairly insensitive to heat. Anhour 's boiling of meat, and even an hour's sterilisation ofmeat at 1150 C.,8^ leaves B unaffected—though Richet%3declares tha t an hour's boiling renders meat incompetent tomaintain growth in the dog. As regards this last observa-tion, however, the destruction of the complettin does notseem to be the cause of the failure of growth, for the dogwas given nothing bu t meat, which is per se an unsuitablediet for a growing animal. According to the same authority,an equivalent amount of meat and bread can be heated toioo° without the process interfering in any way with thegrowth of a dog nourished on this mixture. The observationconfirms the foregoing criticism of the previous one. Thegrowth-complettin in brain tissue will tolerate three-quartersof an hour's heating at 1300 C.,8^ but is somewhat damagedby an hour's heating at 1350. In beans it is unimpaired byboiling,^1 and will even tolerate boiling for six hours.499The boiling of heart, liver, b r a i n y m i l k , ^ tomatoes,899potatoes,773 and carrots,784 has no effect upon the growth-promoting qualities of these nutrients. In polished rice, thecomplettin B is unaffected by ordinary boiling, but is some-what damaged by one-and-a-half hour's heating at a tempera-ture of 1340 C.970

T H E CONDITIONS OF GROWTH 197

The drying of milk969 and the pasteurisation of this^ 1 have no influence; and prolonged heating at a very

high temperature is requisite to destroy the traces of B inthe casein of commerce.56a Orange juice can be boiled untilit becomes dry from evaporation "47 without destroying thecomplettin; and the drying of carrots, potatoes, cabbage,turnips,984 sliced potatoes,773 or vegetables in general, a t atemperature of from 500 to 6o° C.,IO98 does not seem toweaken the growth-complettin in any way. Sliced potatoeshave to be autoclaved for several hours at a temperatureof 1200 C. to produce a markedly injurious effect upon thiscompfettin. In ordinary dried yeast, the growth-complettinis still fully efficacious. Even several hours' heating at1050 C. had no effect upon it.568, ^s8

As we learned in Chapter Four, some authorities believethat the antineuritic D and the water-soluble growth-com-plettin B are identical, and others consider that this identitymay be assumed with considerable probability 6l9, "53* "94;but the respective reactions of these two substances toalkalies and to heat exclude the possibility of their beingidentical.979>x*w I t is proper, however, to point out that ,in experiments of this kind, trustworthy results can onlybe secured when steps are taken to ensure that during theheating process the temperature which is supposed to beoperative shall be reached in the interior of the substanceunder treatment as well as upon its surface. During thecustomary process of sterilising masses of an experimentaldiet at a presumed temperature of n o ° , 1200 C , or more,the temperature in the interior of the mass will only rise(as in the baking of bread) to about 700 C. Portier andRandom 935 have drawn attention to this source of fallacy,and have suggested a practical method whereby the errorcan be avoided. The experimental food is divided into smallportions which are placed in muslin bags tha t hang freely inthe interior of the sterilisation chamber; this will ensurethat the whole substance shall be raised to the desired tempe-rature. The experimenter must, however, be careful toplace a saucer beneath each of the bags, to catch drippings,and these must be remixed with the food after the sterilisa-tion, for otherwise grave errors may ensue.

198 VITAMINS

Sugiura and Benedict 967 found that the growth-com-plettin B was rapidly destroyed by exposure to radiumemanation.

According to Eddy,564 the growth-vitamin is precipitatedby phospho-tungstic acid in an acid solution, and Funk, aswe have seen above, was originally of the same opinion.In a subsequently published paper (Funk and Macallum 563) heinclines rather to the view that when the vitamins are beingisolated by the phospho-tungstic-acid process, this substanceis accidentally entangled in the precipitate. In this con-nexion, Drummond6 l9 has pointed out that any precipitateformed in a solution containing the growth-complettin^ tendsto carry down the complettin with it .

We are led to infer that the growth-complettin mustexist mainly in the form of a colloidal solution. The sup-position is confirmed by the fact that the complettin, likeso many other colloids, is absorbed by alumina.564> 1043, "53

e. Physiological Effects of the Growth-complettin B.

One of the most striking symptoms in animals sufferingfrom B deficiency is the almost invariable onset of gastro-intestinal disorder, IO56> I239 which appears in adults as wellas in growing animals.1^ Experimenters were at firstinclined to believe that the absence of the growth-complettinled to the formation of toxins within the alimentary canal ;these were supposed to be absorbed by the organism. Thetheory was that the action of B was analogous to the actionof the vitamins 563—it was presumed to neutralise thesetoxins or counteract their effects.5x5, "4* I have alreadypointed out that earlier investigators were prone to attributethe ill-success of experiments, with sterilised diets to theabsence of beneficial microbes.783 I t was natural, therefore,to assume that the growth-complettin had a favourableinfluence on the intestinal flora.I046 Open to the same inter-pretation were the repeated observations IO55»JI1^ «95> etc"tha t when the complettin B was deficient in the food theanimals suffered far more from prostration and were moreliable to infections of all kinds than the Controls, whichreceived an ample supply of B.

The general symptoms, however, were also accordant

THE CONDITIONS OF GROWTH 199

with the assumption that the growth-complettin might "inone way or another exert a direct influence on metabolism.IZ24But when Aron I*I3 assumed that this influence might beexerted by the stimulation of peristalsis, he overlooked thefact that the B-containing extracts contained numerousother substances which had long been known to exert astimulating influence on peristalsis. (Cf. Plant 129l.)

The increased power of resistance to infection on a dietcontaining an ample supply of B must, however, be deter-mined by other factors than those which account for naturalimmunity in the ordinary sense of the term, for ZilvaWreported that in guineapigs a lack of B had no effect on theamount of agglutinin and amboceptors in the blood; andthat when the animals of one group were allowed free choiceof food for six months, while the animals of another groupwere placed upon a restricted diet for the same period, nodifference in the complement activity of the blood could bedetected in the two cases. Obviously, the increased powerof resistance when the diet contains a sufficiency of B mustbe the outcome of the general improvement in the nutrition,which enables the animals to resist noxious influences moreefficiently than when they have become weak and sicklyeither from natural causes or through a diet artificiallyrendered inadequate.

Drummond687 has published an observation which hasnot been confirmed by any other investigator, tha t whenthere was a lack of B in the diet the animals suffered fromkreatinuria. This symptom must have been due to a generallack of bases rather than specifically to the lack of B, for,as I have repeatedly shown, a lack of bases almost alwaysleads to an increased excretion of kreatin.

But the foregoing assumptions do not touch the cardinalpoint in the mode of action of the water-soluble growth-complettin. We have already learned that Funk was ledin the first instance to assume the existence of this com-plettin by the striking observation that its absence from thefood made the maintenance of weight impossible in adultanimals, and the maintenance of normal growth impossiblein immature animals. The first signs of a lack of B in thediet«*4 consist of arrest of growth, loss of weight, general

200 VITAMINS

debility, and loss of appetite which may culminate in theabsolute refusal of food. Nervous disturbances have some-times been observed shortly before death. (Cf. Drum-mond687.) They must probably be ascribed to the use of adiet deficient in D as well as in B ; in that case they wouldbe dependent upon the absence of the water-soluble anti-neuritic principle and not upon the lack of B.

The most remarkable point about the effect of B is, justas in the case of vitamin or of D, that very minute quantitiescan be shown to have an influence.10^8, Io6° When we findthat the addition of as little as half a gramme of driedclover or spinach to the diet can render it competent to inducenormal growth, we realise that the quantity of complettinrequisite must be extraordinarily small.

When discussing the efficacy of A, we learned that bothfor this and for B the law of the minimum is valid. Drum-mond 687 points out that, within certain limits, the extent ofgrowth is proportional to the amount of B in the food. Thefirst result of the addition of B is shown in an increase ofweight, this occurring also in adult and healthy animals I2*4;subsequently, in immature animals, vigorous growth speedilyensues. Simultaneously there is an improvement in thegeneral appearance; if the tint of the skin has beenmorbid, a healthy colour is restored; in hairy animals, thecoat becomes thick and glossy once more.1*^, 1268 £ u t w e

must bear in mind the possibility that the latter pheno-menon may be the outcome of the simultaneous administra-tion of D.

FigueiraI046 noted that in sucklings extracts of wheatbran, when given in large quantities, were apt to inducediarrhoea. We have no reason to suppose that this symptomis due to the growth-complettin, for Abderhalden and Schiffi-mann **73 have shown that B in watery extracts is absolutelynon-toxic both in frogs and in mammals. Alcoholic extractsof bran gave rise to accessory symptoms, and especially totonic contraction of the bloodvessels, which were not notedwhen watery extracts were administered.

The growth-complettin, however, has certain bad effects.As Funk pointed out, it may not merely affect the bodyand the organs favourably, but may also promote the growth

T H E CONDITIONS OF GROWTH 201

of tumours should these exist. Conversely, Hopkins hasproved tha t in animals fed on a B-free diet, tumours grewto only about one-fourth the size attained by similar tumoursin controls. Copeman, who reports these experiments,deduces from them a method for the t reatment of cancer,and declares t ha t he has secured good results by prescribinga diet poor in # A Mackenzie,1^ in answer to this sugges-tion,, has pointed out t h a t Drummond's experiments havedemonstrated the impossibility of starving the tumourwithout starving the host.

# 7. BEHAVIOUR OF THE ENDOCRINE GLANDS.

McCarrison I24° has shown tha t the endocrine glandsshare in the general malnutrition. Nearly all of them undergoa t r o p h y ; bu t the adrenals are an exception, for when thereis a deficiency of B they undergo hypertrophy just as theydo when there is a deficiency of vitamin. The requirementof the endocrine glands in respect of B seems to be small,just like tha t of other organs ; bu t their needs are so vitaltha t they have the preference over the rest of the body asregards the utilisation of B. This is proved by an interest-ing experiment made b y Stewart.1*01 H e gave white ratsso spare a diet for a period ranging from eleven to twenty-two days after their birth, tha t they did not put on weighta t all from the t ime of bir th. Nevertheless, the animals grewconsiderably in l eng th ; and the head increased in weightb y about 45 % at the expense of the t runk and the extre-mities. Simultaneously, the increase in weight in the visceraamounted to 46 %, tha t of the skin to 25 %, and tha t ofthe muscles and bones taken together to only about 6 %.The most remarkable point was the behaviour of certainspecial organs. As compared with conditions in the new-born animal, the liver had fallen off by 23 % and the thymusb y 49 %, whilst the thyroid, the ovaries, the lungs, and theadrenals, remained of the same weight as a t birth. Someof t h e other organs had increased in weight, the increasein certain cases being enormous: the pineal gland washeavier by 21 % ; the heart, by 26 % ; the pituitary body,b y 29 % ; the^ stomach and intestines, by 40 % ; t he spleen,by 33 % I the spinal cord, by 83 % ; the kidneys, by 90 % ;

202 VITAMINS

the brain, by 125 % ; the eyes, by 146 % ; the epididymesby 225 % ; the testicles, by 374 %.

This led Funk, as early as 1913, to the assumption thatthe action of the growth-complettin cannot be a direct one,but must be effected indirectly by a stimulation of theactivity of the endocrine glands. Abderhalden 953 takes thesame view. He regards the complettins as stimulants, eachof which has a specific action upon certain groups of cells;in one case, upon those of the digestive glands; in another,upon nerve cells; in another, upon the cells of the endocrineglands; in another, upon the involuntary muscle of theintestine; and so on. <%

It has, in fact, long been known that there are intimaterelationships between growth and the activity of variousglands. For instance, the reproductive glands, prior to thedevelopment of their reproductive functions proper, appearto form internal secretions which promote growth. Weknow of the thyroid secretion that it has a special influencein promoting growth; on the other hand, hypothyroidismin youth leads to an impairment of the whole bodily develop-ment and to the most various disproportions and malforma-tions. Very instructive in this respect are some of Abder-halden's dietetic experiments, notably those on tadpoles.

Especially important, in this connection, is the activityof the pituitary body; this statement concerns the internalsecretion of the anterior lobe, for that of the posterior lobehas no influence on growth. Consequently, HOchst's hypo-physin ia96 has quite a different effect from the tethelin firstprepared by Robertson and Ray from the anterior lobe.Tethelin is a well-defined chemical entity, having the com-position of a j8-imid-azolyl-ethyl-amine; and its mode ofaction has been elaborately studied by Robertson and Rayin masterly fashion.485, 486,487, 548. 862,863,864,865,1141

The most characteristic feature of the action of tethelinis that it stimulates the growth of the mote active cells, andtends to inhibit the growth of connective tissue. Therebythe youth of the tissues is preserved, and a powerful influenceis exercised upon tha, onset and the duration of sexualmaturity and sexual functioning. The effects of tethelinvary ^greatly/ according to the length of time for^which it

T H E CONDITIONS OF GROWTH 203

is given, and according to the phase of life during which i tis administered. When given continuously from bir thonwards, it induces gigantism, but the giants thus producedhave a short life. On the other hand, when tethelin is givenonly during early youth and then discontinued, i t leads toincreased growth, and the effect upon growth lasts beyondthe period of administration; but the prolongation of thestage of youth thus determined leads, further, to a generalprolongation of life. Generally speaking, these results havebeen confirmed by Marinus ,^ and by Abderhalden andBrammertz *376; in so far as there are differences betweenAbderhalden and Brammertz's results and those of Robertsonand Ray, we have to remember that the experiments of thelatter were performed on mammals, and those of t he formeron tadpoles. Almost simultaneously with the first experi-ments of Robertson and Ray, Clark 446 made investigationsinto the effect of the anterior lobe of the pi tui tary body onfowls. Not only did he note an enhanced growth in thebirds, but he believed that their laying was favourablyinfluenced. More recently, Simpson "93 has experimentedon the same lines, and declares that tethelin has no favour-able effect upon laying. Larson ^4 found that in thyroidecto-mised animals, tethelin had a favourable influence upon thegeneral condition and increased the duration of life in theanimals that had been subjected to this operation.

According to Popielski,^** tethelin, or ra ther /J-imid-azolyl-ethyl-amine, does not exist ready-made in t he tissues,and is certainly not found in the anterior lobe of thepituitary body. On the other hand, he has found this sub-stance in the stomach, and he assumes tha t i t mus t be adecomposition product formed during the isolation of thereal active body. However this may be, there can be nodoubt that neither tethelin, nor the natural secretion of theanterior lobe of the pituitary body, represents t h e growth-complettin of which we are in search, for the effects of thesesubstances differ too much from those, of t he growth-complettin. Moreover, when the milk of a lactat ing animalis deficient in B, and the growth of t h e sucklings is conse-quently below par, we cannot improve growth b y addingportions of the anterior lobe of the pituitary t3fody to the

204 VITAMINS

maternal diet, whereas such improvement in growth promptlyfollows the administration of B to the mother.657

According to Robertson and Ray,11** cholin has a similareffect to tethelin upon subsequent growth; but cholin iseven more destructive to life, for large quantities of cholinhave to be administered. These are stored up in variousorgans and exercise a noxious influence. The effect ofnumerous other substances on growth has been studied. I thas been found tha t hydrocithin 399 has a favourable effecton growth; and, on the other hand, tha t cholesterin 353, 53°, 53*and lecithin 355.53° tend rather to retard growth. No sub-stance with a genuinely analogous influence to that of B hashitherto been discovered. The nature of B and i ts modeof action still remain to be elucidated, bu t there is one morepoint to which I must refer before leaving this subject.

B appears to have a peculiarly powerful influence uponthe growth and the activities of the endocrine glands, forthese glands (with the exception of the adrenals) atrophywhen B is deficient. Now we have to remember that growthis the resultant of the interaction between the secretions ofcertain glands—some of which are known to act in this way,while the effect of other endocrine glands on growth perhapsstill remains to be discovered. There are, therefore, con-siderable grounds for accepting a hypothesis put forwardby Funk. He supposes that B cannot be synthetised inthe body, and is therefore not (as we have found the com-plettin D to be) directly indispensable. B, suggests Funk,must be indirectly effective, by keeping the endocrine glandsin good order and by stimulating their activity. Additionalsupport to the hypothesis may be furnished by the observa-tion that—though, in general, the growth of sucklings isdependent upon an adequate supply of B to the mother—in the absence of this, normal growth can be secured by thedirect administration of B to the sucklings.

8. IMPORTANCE OF THE NUTRITION OF THE MOTHER.

The proper feeding of the mother from the first momentshe conceives is of decisive importance to the growth of theoffspring. The mother's diet even before she conceives isnot without influence in this respect. We have, of course,

T H E CONDITIONS OF GROWTH 205

to reckon with a factor competent, in a measure, to correcteven grave errors in the maternal diet—a factor but forwhich the animals we are pleased to term civilised humanbeings would long ere this have died out. I refer to themarvellous energy displayed by growing animal organismsin securing, even in the most unfavourable circumstances,the nutrients requisite for maintaining life and promotinggrowth. To a degree, moreover, a like energy is displayedby the mammary glands, the maternal organs which aremainly responsible for the wellbeing of the offspring duringthe period tha t immediately follows birth.

As regards the importance of diet even before concep-tion, this has been clearly proved by the researches ofZuntz,861 who found that an exclusive diet of protein andfat, or an exclusive diet of protein and carbohydrate, ledin both sexes to grave impairment of the reproductive faculty.The animals conceived less frequently, and had smallerlitters, although the individual offspring were normal insize, structure, and weight. Zuntz also found—as R6se fy> 7°had found more than ten years earlier—that a long-lastingdeprivation of calcium has likewise a deleterious effect uponthe reproductive powers, but that in this case the wholedevelopment of the offspring is seriously affected. In thisconnexion, I must refer once more to Urbeanu's researches,which showed that when the supply of calcium to fowls wasrestricted to an amount that seemed just sufficient for themaintenance of the maternal organism, sterility becameapparent after three or four generations. McCollum andhis collaborators, too, and also Osborne and Mendel, havefrequently drawn attention to the importance of a properdiet to the integrity of the reproductive powers; and moreespecially do they stress the fact that the thriving of a singlegeneration affords no guarantee that the diet is a satisfactoryone. In many cases, the effects of an inadequate or an ill-balanced diet do not become apparent for several genera-tions. Only then do we find that the animals conceive morerarely, and that the offspring appear more and more weakly,until ultimately complete sterility, or failure of the lactealsecretion, ensues.

If the mother's diet, though containing a sufficiency of

206 VITAMINS

proteins, contains these in a form which is not fully adequatefor promoting growth in the offspring, the maternal organismsupplies the foetus with what is lacking by drawing uponthe maternal store. Even inanition in the mother will notprevent reproduction, and the structure of the offspringseems perfectly normal, but Zuntz 861 states that the weightis below the average.

Insufficiency of the maternal diet in respect of proteinhas no effect upon the composition of the milk 2*6> 56r;Behre "56 and Stern "57 report that the inadequacy of fodderduring the war had no notable effect on the composition ofcow's milk. All authorities are, however, agreed that thequantity of milk falls off when the diet is insufficient.*"1

The long-continued malnutrition of nursing mothers thatprevailed throughout Central Europe during the war, ledto a reduction in the lacteal secretion. Ultimately, defectivenutrition leads to a degeneration of the mammary glands,and changes in the composition of the milk then ensue.X(>4*On the other hand, McCoUum and Simmondsxoa6 reportthat when the maternal diet is exceptionally high-grade,the secretion of milk is abundant, and the growth of theoffspring is extremely active.

The faculty of the lacteal glands which enables them toextract from the maternal organism whatever is requisitefor the production of normal milk, renders the mother'smilk the best nutrient for the offspring during the earlyphase of life. Happily a conviction of this truth has gainedground in Germany of late, not only among doctors andgovernmental authorities, but also among women through-out the population. Bergmann835 insists that even whenthe mother's milk is somewhat lacking in quantity, a breast-fed infant will tlyive better than a baby sufficiently fed byhand.

The inorganic salts requisite for the formation of normalmilk are likewise extracted with great energy from thematernal organism.1026 Carl RQse,6^ 7° who experimentedfor a considerable period on goats, could not find thatextensive variations in the diet produced any changes iathe composition of the milk of these animals. But th©mother cannot pitmde what she herself does not possess,

THE CONDITIONS OF GROWTH 207

and ultimately therefore, when there is a persistent lack ofinorganic salts in the maternal diet, the composition of themilk suffers. According to Hart and Steenbock95* therethen ensues grave debility in the sucklings.

The mammary glands also have the power of concen-trating into the milk the growth-complettins A and B thatare stored in the maternal organism, so that when thesesubstances are deficient in the mother's diet, the milk willcontinue for a time to contain enough to promote normalgrowth i n the offspring.1026 Still, the influence of the maternaldiet is marked in the case of both these complettins. Refer-ence h a s already been made to the fact that in cows theamount both of A and B in the milk varies with the seasonand the fodder J33<>; the milk is only adequate for the main-tenance of growth in the offspring when the maternal dietis itself adequate in this respect. Even in cases when thegrowth of the offspring is apparently taking place in normalfashion, we may find that the provision of an extra supplyof B for the mother will be followed by a notable accelera-tion of growth in the sucklings.561

During weaning, and even later—when the young animalshave become habituated to an independent diet, the mother'smilk m a y continue to serve as a corrective for deficienciesin the diet.1026 If any further emphasis of the importanceof breast-feeding were requisite, and if anything could serveto persuade neglectful mothers to fulfil their duties in thisrespect, a general diffusion of knowledge concerning thework done during the last ten years upon this topic of thefactors of growth would suffice. In Saxony, the State hasrecently instituted a special department for hygienic enlighten-ment, and it is eminently desirable that this new departmentshould pay special attention to the spread of a knowledgeof the foregoing facts.

9. EFFECT OF THE INHIBITION OF GROWTH UPON

SUBSEQUENT GROWTH.

Another remarkable phenomenon must be consideredbefore dismissing the subject of growth. As long ago as1912, Osborne and Mendel **5 pointed out that when (for

208 VITAMINS

one reason or another) the diet had been such as to checknatural growth for a considerable period, normal growthwas resumed as soon as the error in diet had been remedied.Among dietetic defects leading to an arrest of growth, theseauthorities allude to the following: 370 an insufficient supplyof protein, or the lack of certain nitrogenous tissue builders;the lack of A or B ; the lack of certain inorganic nutrients,or an improper ratio of these in the diet. In such circum-stances, the inhibition of growth may be protracted farbeyond the normal period of growth, and yet growth mayeven then be resumed when the noxious influence ceases tobe operative.370,465 Thereby, the total duration of life maybe considerably increased, and the animal may in the endattain its normal size.

Growth which is resumed after such an arrest proceedsat a more rapid pace than usual, attaining for a time amagnitude which is due to an excess of compensation. (Cf.Osborne and Mendel *25> $*; Thompson and Mendel 7*5.)

Northrop660 has published some interesting researcheswhich corroborate the work of Osborne and Mendel. Hefound that such a temporary arrest and subsequent resump-tion of growth were actually followed by an abnormal pro-longation of life—in the larvae of flies, for instance. Butthe prolongation affected only the phase of life subjected tothe experimental modification. Thus, in these particularexperiments, it was the larval period of life which was pro-longed, whilst the life of the pupa and of the imago remainedof average duration. I t would seem, therefore, as if fromthis point of view the different stages represented differentindividuals.

In their first publication on the subject, Osborne andMendel insisted tha t a restitution to the normal or an excessof compensation was only possible when the weight of theanimal had at least been maintained during the period inwhich growth was suspended. Whenever the diet had beenso inadequate as to cause loss of weight, the subsequentgrowth was inevitably impaired. Jackson and Stewart,IO59who have substantially confirmed Osborne and Mendel'sobservations, nevertheless insist tha t when undernutritionhas led to a temporary arrest of growth, the growth tha t

T H E CONDITIONS OF GROWTH 209

ensues after the defects in the diet have been made goodis not fully adequate, so that throughout life the animalsexhibit stigmata due to malnutrition during the develop-mental period.

An excellent idea of how important a satisfactory dietis to the wellbeing of children can be derived from a reportmade by K. B. Rich "41 concerning the work of the educa-tional authorities in the Chicago elementary schools. Investigation showed that the treatment of tonsillar hypertrophies,carious teeth, adenoids, and fiat-foot, was almost ineffective,although great expectations had been formed. What proveddecisive for physical wellbeing was cleanliness, light, freshair, exercise, and, above all, attention to diet. When theseenvironing conditions were improved, there was a concurrentincrease in weight and stature.

10. SUMMARY.

We may sum up in a single sentence what has gone beforeby saying that normal growth is preeminently dependentupon a rationally composed diet. Children must be given asufficiency of food, and the protein must be as high-gradeas possible. From this point of view, potatoes and milkare the bes t ; cereals are less suitable, unless the inadequacyof their proteins is made good by giving milk in addition.The diet must also contain a sufficiency of complettins: Acan most advantageously be provided in the form of milk,butter, or spinach; fresh vegetables and fruit in abundanceare a satisfactory source of B. The diet should containfrom five to seven times as much of vegetables, potatoes,and salt-rich fruit (apples and pears are poor in this respect),as of meat, eggs, or cereal products—for otherwise an ade-quate excess of bases cannot be guaranteed. Care must betaken that the nutrients shall contain enough sodium andcalcium, the latter being especially important. The sodiumcontent must be at least one-fifth of the potassium content,and the calcium content must be not less than five timesas great as the magnesium content. The latter requisiteis sometimes difficult to fulfil; in regions where the wateris poor in lime, it will be indispensable to give about three-quarters of a pint of milk daily.

210 VITAMINS

Before I close this chapter, I must say a few words aboutthe feeding of children in Germany and Austria during thewar. The conflict brought tragedies enough in its train,but the matter we have now to consider was one of the mosttragical of all. It has been proved that, in German Austriaand in Germany, approximately one million children perisheddirectly or indirectly from wartime feeding, and that almostall the children who survived were more or less seriouslyinjured by the inadequacy of the diet. Perhaps the worstfeature of the case is that the blame for what happened canonly be indirectly ascribed to the blockade, for the chieffactor was the stupidity of the German dietetic experts andof the government that acted on their advice. I repeatedlydrew attention, both by word of mouth and in writing, tosome of the grave errors that were being committed; butmy remonstrances had no effect, and it is but a poor andbelated satisfaction that the results of the British, American,and international commissions of enquiry have shown mycriticisms to have been fully justified.

Consider, first, the most outrageous of all the errors ofwartime feeding—the crazy, the utterly inexcusable, slaughter-ing of milch-cows in order to secure a few paltry pounds ofmeat. To attain this lamentable result, and to stop themouths of clamorous flesh-eaters, our precious herds weredestroyed. In the most short-sighted fashion, milkers werebutchered each of which within a single year could haveproduced its own weight of invaluable nutrients in the formof milk, and no one stopped to think that thereby i t wasbeing made impossible either to breed for the future supplyof meat or to provide for the subsequent victualling of thepeople with butter (rich in A) and with milk (rich in A, B,C, and inorganic salts). (Cf. Mason1011.) Almost as badwas the potato control, whereby the price of one of our mostimportant articles of diet was fixed at a figure at which itdid not pay the farmers to grow the tuber. But, apart fromthese two errors, which are at least easy to explain, I haveto think of two others which can only be described ascriminal: the removal of the germ from cereal products;and the steaming or scalding of vegetables for conserves.

It has long be£n known that the highest-grade protein

THE CONDITIONS OF GROWTH 211

in every grain, and nearly all the fat of the grain, are con-centrated in the germ. Nevertheless, there was no hesita-tion about extracting the germ of the grain in the milkingprocess in order to use the fat thus secured for the feedingof the already over-rationed munition workers. It was sup-posed that the germs, after the removal of the fat, were tofind their way back to the community-at-large in the formof meal for breakfast use. I have never been able to learnwhat really became of them. In actual fact, throughoutthe war, we received at Weisser Hirsch on two occasionsonly a ration of a germ-containing meal, each person havingabout enough to make a small cup of gruel. One excusegiven for the removal of the germ was that the keepingqualities of the flour were thereby improved—but thesekeeping qualities were of very little importance, seeing thatwe were all forced by hunger to eat our rations with theleast possible delay. Besides, the statement is untrue. Thewhole procedure was a robbery of the energies of the Germannation and a crime against our growing youth.

Even more serious, if possible, was the second error, thebleaching of vegetables before they were dried. In a subse-quent chapter, this will come up again for fuller considera-tion, and it will suffice to say here that the mere steamingof vegetables for five minutes dissolves out so large a pro-portion of the inorganic bases that the residue contains anexcess of acids. Simultaneously, the vitally important com-plettins are almost entirely dissolved out of the vegetables.

Chick "37 and Dalyell ,1^ and also Block Ia8* (a Germaninvestigator), in their studies of wartime diets in Germany,insist that the worst feature was the impoverishment of thefood in respect of A, B, and C. British doctors and physi-ologists IO55 are unanimous in the opinion that the maincause of this defect was the method of preparing vegetables.The before-mentioned authorities record a number of strikinginstances in which severe attacks of scurvy in children werepromptly relieved by the addition to the diet of carrot juiceor raw spinach, or in some instances of butter or of codliver 6il.

Among German medical practitioners, there are somewho have long been aware of these facts, and have turnedtheir knowledge to practicalfaccount. Above all, I must

212 VITAMINS

refer to the work of Erich Muller and his collaborators, andto that of Aron, who, in the circles entrusted to their care,were able to secure admirable results with the scantiest ofmeans. Block, too, showed that in severe cases of mal-nutrition in children, the addition of fresh vegetable juiceto a milk and vegetable diet gives excellent results.

These views of mine, which to some extent had beenadvocated earlier by Lahmann, are now being widelytrumpeted as a brilliant foreign discovery. I t may be hoped,therefore, that even the Germans will at length break theshackles of tradition; and that, even in Germany, a currentof fresh air will invigorate the science of dietetics.

ADDENDUM TO CHAPTER F O U R : SPRUE.

a. Clinical Picture.

Among European residents in the tropics, especially inthe East Indies and in the Sunda Islands, there frequentlyoccurs a remarkable disease known as sprue or psilosis. I thas not hitherto found a satisfactory place in the nosology.In the account I propose to give of this disorder, I am guidedchiefly by the description given by Brugsch and Kraus,Handbuch der allgemeinen Therapie, section on TropicalDiseases. The illness begins with slight gastro-intestinaldisturbances, which have nothing characteristic about them,and come and go. From time to time, isolated patches ofinflammation appear on the tongue, to disappear again com-pletely. In the course of years, the attacks grow more fre-quent, and the inflammatory manifestations on the tonguebecome more severe and last longer. When the disease isfully established, the inflammatory foci on the tongue gradu-ally spread until they coalesce. The lingual epithelium dis-appears, and on the inflamed surface can be detected verysmall suppurating vesicles or extremely sensitive circum-scribed minute ulcers. Thus in course of time the surfaceof the tongue is to an increasing extent denuded of epithe-lium ; the mucous membrane is dry and fissured; thepapillary body has vanished, the papillae being replaced byovergrowths of connective tissue. The whole musculature ofthe tongue has atrophied, so that the organ has become

T H E CONDITIONS OF GROWTH 213

extremely small , deeply furrowed, and thin. The gums andthe rest of t h e buccal mucous membrane may be sympa-thetically affected with inflammation; the suffering may befurther increased by salivation, or the secretion of a tena-cious mucus, o r sometimes by dryness of the mouth. Thesense of taste is greatly impaired; the saliva has becomeacid, and the sulphocyanate may have completely / disap-peared from t h e secretion.

Inflammations of the rest of the upper part of the ali-mentary t rac t complicate the clinical picture, leading todifficulty in swallowing, pain on swallowing, a sense of full-ness, flatulence and eructation, heartburn, and, in exceptionalcases, vomiting. Although in the early stage of the affectionthe appetite i s often excessive, it subsequently falls off, withthe onset of achlorhydria. Burning thirst is common; theabdomen is i n a state of flaccid distension. Borborygmi,and the rapid onward movement of the intestinal contents,show that excessive fermentation is going on. Colic is,however, present only in acute exacerbations of the disease*

The bowels act especially during the morning hours,and the evacuations may number ten or more, though theyare sometimes suppressed for a while. The stools are gene-rally of the consistency of pap, foamy, yellowish white incolour ranging to grey or greenish, though there is no signof jaundice. Their reaction is acid. They contain an excessof fat, but n o mucus or blood.

At a comparatively early stage the liver is reduced insize, but this m a y be no more than an outcome of the generalatrophy. T h e r e are no special symptoms showing anyinvolvement of the respiratory, circulatory, or urinary system.The urine sometimes contains an excess of bile-pigments;and when t h e stools are suppressed, indigo can be detectedin the urine.

There is extreme emaciation; the skin becomes flaccidand wrinkled ; ultimately death occurs in a condition ofcachexia in which the patient has come to look almost likea mummy.

b. Pathological Anatomy.

Generally speaking the blood seems normal in sprue ;but in severe cases, owing to the malnutrition, intense

214 VITAMINS

anaemia ultimately sets in, so that the haemoglobin richnessof the blood may fall to 40 % of the normal, or even lower.In the worst cases, the blood may come to resemble that ofpatients with progressive pernicious anaemia. But, apartfrom these extreme instances, the characteristics of the bloodare those resulting from chronic toxaemia and from a plasticinhibition of haematopoiesis.

The pathological anatomy of this disease does not furnishany etiological explanation, for the pathological changesare no more than the results of the abnormal fermentationsin the intestine. In the ileum there is a flaccid distention;the villi of the mucous membrane have atrophied and almostdisappeared; thus the wall of the gut may be transparentand as thin as paper, unless thickened by oedematous infiltra-tion. There are numerous punctiform ecchymoses, some-times larger extravasations of blood, and bile-stained patches;these changes give the bowel a remarkable motley aspect.The oesophagus and the stomach are always affected, thecoats being in most cases thickened, inflamed and infiltrated,or selerosed. The mucous membrane is wrinkled, thickened,here and there atrophic, and often flecked with haemorrhages.The mesenteric glands are enlarged and strongly pig-,mented; or, in some cases, atrophied and cirrhotic. Theirritation of the bowel may spread to the peritoneum, leadingto local peritonitis and the formation of adhesions. Thereare no marked changes in the bone-marrow, which is, how-ever, greatly lacking in fat. The other organs all manifestthe effects of the general atrophy.

c. Prognosis.

In advanced cases, the prognosis is unfavourable, andeven in the early stages it is dubious. A cure will in anyevent take a very long time, and will demand, during thisperiod and afterwards, from a seriously debilitated sufferer,the display of a great deal of patience, tenacity, andenergy. In slighter cases which come under treatment atan early stage, the conscientious carrying out of the pre-scribed course of treatment may affect a c u r e ; butrelapses will only be avoided by extreme caution on thepatient's part.

T H E CONDITIONS OF GROWTH 215

d. Treatment.

Rest in bed is needed only in severe cases. The mainthing is to promote improved nutrition, by checking fer-mentation through reduction of the carbohydrates in thediet, and by lessening the putrefaction of nitrogenous sub-stances within the bowel by restricting the supply of pro-tein—thus securing a better utilisation and absorption ofthe food. Fat is very badly borne. A milk diet is generallythe best, the milk being given unboiled, and it must not betoo rich in cream. We shall do well to dilute the milk withVichy water ; if it is not borne even then, the effect shouldbe tried of using an even more strongly alkaline water, suchas Ems, for the dilution. Remarkable results sometimesfollow the giving of fresh raw fruit, especially strawberries,but also bilberries and gooseberries. By degrees at temptsmay be made to increase the amount of protein in the food.Potatoes are well borne. When medical experts in tropicaldiseases assure us tha t vegetables cannot be tolerated, andmost often be withheld for many years, we presume thatwe are once more encountering the fallacy which has nowhappily become obsolete as regards the treatment of gastricand intestinal disorders in general. But it is certainly ofthe utmost importance tha t anyone who has suffered fromsprue should for years to come shun strongly-spiced, rich,or fatty articles of d ie t ; a single indiscretion of this kindmay prejudice the whole course of treatment.

e. Etiology.

As I have already shown, medical science is gropingin the dark where the question of the etiology of sprue isconcerned. I t is certainly presumptuous for a person likemyself, not being a practitioner of medicine, to express anopinion on the m a t t e r ; but I feel nevertheless tha t myknowledge of the way Europeans feed in India, in conjunc-tion with my special experience of modern theories of nutri-tion, will perhaps enable me to give some pointers.

First of all it must be remembered that , as far as dietis concerned, European life in India is about as unnaturalas can possibly be conceived. The British have taken with

216 VITAMINS

them to the east their national preference for a meat diet,and have wedded it to the indigens' taste for highly seasonedrice. The burning thirst induced by such a diet is slakedby vast quantities of iced and usually sweetened drinks(alternating with tea), which are frequently loaded withlarge doses of alcohol.

Naturally this regimen is extremely injurious to thegastro-intestinal tract. In the United States, too, iceddrinks are greatly in vogue, and we are informed that thepractice of consuming these beverages is found to be mostunwholesome, giving rise in the first instance to acute dis-turbances, and subsequently in many cases to grave chronicdisorders. The excessive stimulation of the mucous mem-brane is aggravated in India by pungent curry, and usuallyin addition by tobacco and alcohol. How can we expectthe unfortunate mucosa to tolerate all this without inflam-imatory reaction ? Now, we know that gastric disordersfrequently affect the condition of the buccal mucous mem-brane, which becomes thickened or inflamed, often withthe formation of aphthous ulcers.

The wonder really is that cancer is not more frequentin tongues that are so much maltreated. Perhaps the reasonis that , as previously explained, for the development ofmalignant tumours there is needed an abundant supply ofB—this substance being so thoroughly utilised that thetumours are themselves free from B. In actual fact, thediet of Europeans in India, where fruit is scarce, is extremelypoor in B ; and this scarcity may account for many of thesymptoms of sprue. First of all it may account for thereadiness with which the buccal mucous membrane—whichin general is so resistant and has such remarkable powersof regeneration—becomes inflamed and ultimately atrophies;and the same remark applies to the mucous membranethroughout the gastro-intestinal tract. We may supposetha t the deficiency of B leads, not merely to a lowering ofthe capacity for resistance, but also to a grave impairmentof regenerative power, so that inflammation tha t has onceoriginated tends to persist indefinitely.

There can be no doubt, moreover, that the excess ofacids in the food plays a notable part in the etiology; the

T H E CONDITIONS OF GROWTH 217

acidity of the saliva suffices to prove this. As to the partplayed by the metabolism of inorganic salts in the causationof sprue, nothing definite can be said in the absence ofdetailed investigations. I t is noteworthy, however, thatthe nutrients recommended for the treatment are all charac-terised by excess of bases and richness in calcium. Theeffect of fruits in th is respect must be conspicuous, for weshould have anticipated tha t the skins and pips of the fruitsfound helpful would have irritated the bowel quite as muchas any vegetables.

The fact tha t vegetables are not well borne is, of course,partly explicable b y the irritant effect of the indigestibleresidues. But there are many vegetables which are fairlywell borne in sprue—for instance, young spinach and youngcarrots, both of which resemble potatoes in leaving com-paratively little i rr i tant residue. I t is, therefore, not easyto understand why potatoes should be so much better tole-ra ted than vegetables in general. The difficulty is all thegreater seeing tha t vegetables in general are pooF in carbo-hydrates, whereas potatoes consist so largely of carbohy-drates, and yet one of the main points in the treatment ofsprue is to restrict the supply of carbohydrates. May notthe explanation of this apparent contradiction be found inthe fact tha t most of t he other sources of carbohydrate arecereals, which contain a notable excess of acids, whereaspotatoes are rich in bases ? We shall be the more inclinedto accept the explanation when we remember that by thecustomary methods of what is regarded as refined cookery,vegetables are robbed of their excess of bases, and tha t thism a y be the main reason why they are badly borne in sprue.

Such a theory is supported by another consideration.Milk contains only a slight excess of bases; and yet (at anyra te in the early stages of sprue) i t is not well borne unlessits excess of bases is increased by dilution with mineralwaters containing liberal amounts of bicarbonates, i.e. ofalkaline salts.

The favourable effect of fruits can perhaps be explainedb y their C content, seeing tha t milk is rather poor in C.Perhaps the frequency of haemorrhages in sprue is referablet o C deficiency, and i t may be tha t closer examination

218 VITAMINS

(especially in post-mortems, when attention has been directedto the point) will show further signs of masked scurvy. Imake the suggestion with all reserve. In any case, fntitsmay furnish a welcome augmentation of the calcium supply,for the calcium content of milk seems to be inadequate inthe long run for adult human beings.

As far as the widespread atrophy of the organs is con-cerned, the main cause of this is doubtless the generalfailure of nutrition consequent on the digestive disturbances.But when there is defective nutrition because the diet isquantitatively inadequate though qualitatively adequate,we find general atrophy differing from that characteristic ofthe deficiency diseases in that the glands continue to func-tion. In the acomplettinoses, on the other hand, impair-ment of glandular functioning makes itself apparent a t avery early stage. We have seen tha t this is especiallycharacteristic of a lack of vitamin, of B, and of D ; and theearly onset of slight acidity in sprue suggests an inadequacyof the diet in one of these respects. A survey of t h e fore-going considerations enables us to infer that the lack is notone of vitamin or of the antineuritic D, but t h a t B isprobably lacking.

I t would be of equal value to suffering humani ty and toscientific medicine if the problem of sprue were to be recon-sideredjwith the aid of the modern methods of dieteticphysiology.

CHAPTER SIX

T H E FAT-SOLUBLE COMPLETTIN A

i . HISTORY ; ITS ISOLATION,

IN" the previous chapter, when discussing the determinantsof growth, it was necessary to consider some of the peculi-arities of the complettin A in order to fill in our picture ofthe growth-factors. But the efiects of the complettin Aon the animal organism are not restricted to a favouringin growth; they are so multiform that a special chaptermust be devoted to the fat-soluble complettin A.

The starting point in the study of the fat-soluble com-plettin was the paper published by Wilhelm Stepp,93 a pro-fessor a t Giessen, in the year 1909. He observed tha t adiet which had previously been quite adequate, proved afterextraction with ether and subsequently with alcohol incom-petent t o maintain growth in mice and to keep the animalsalive. If the solvents had been used hot, the readditionof the ether extract and of the alcohol extract did not makethe diet adequate. If, however, the alcohol extract hadbeen made with cold alcohol, the return of this extractrestored adequacy to the diet.

The report seems to have been overlooked, for otherwisei t would surely have led to further and more detailed investi-gations. A second report by Stepp,234 published in the year1912, also failed for the time to at tract attention. In thisinstance Stepp showed tha t the active substances were notvery resistant t o h e a t ; they were completely destroyed bytwo days' boiling of an alcoholic solution, or by boiling thewhole food in alcohol for forty-eight hours, or by prolongedboiling in water. At tha t date, Stepp was inclined to regaspithem as lipoids. When a food had been rendered inade-

219

220 VITAMINS

quate by such treatment, its adequacy could be restored bythe addition of an extract made with cold alcohol from otherportions of food. I t was manifest, therefore, t h a t theorganism of the mouse was incompetent to synthetise thesesubstances, and this led Stepp to infer that the lipoids wereabsolutely essential constituents of food. Two years later,Stepp supplemented his work with a report 396 showing thatthe denatured food could not be rendered adequate b y theaddition of pure fats. But the addition of various lipoidcompounds was likewise found ineffective in this respect.An alcohol and ether extract of yolk of egg was, however,extremely active, so that Stepp continued to regard a com-bination of vitamins with certain lipoids as the active prin-ciple. The view seemed to him to be confirmed when hewas able to prove 5*6 that the denaturation was effectedmainly if not exclusively by the alcohol extraction and notby the ether extraction; and to show that the denaturedfood would be rendered adequate by an acetone extract ofyolk of egg, and much better by an alcoholic extract of yolkof egg made subsequent to extraction with acetone. Insome instances, the acetone extract was inactive whereasthe alcoholic extract was effective. Vitamins alone, andvarious lipoid compounds, were ineffective; the combinationof vitamins and brain lipoids was effective in certain instances.

The investigation did not enter the right t r a ck untilHopkins and Neville *67 noted in 1913 that the artificial dietemployed by Osborne and Mendel could only maintainweight in mice for a limited period, but that when 2 cc. offresh milk were added to the food (a supplement whichincreased the total dried substance by only 4 %) t h e miceremained perfectly well-nourished. This observation wasconfirmed by Osborne and Mendel.*95 They found t h a t onthe artificial diet, as originally supplied, rats could be keptgoing for a considerable period, even with increase of weightand a moderate amount of growth; but ultimately growthceased, the weight fell off, and the animals perished. If,however, during the critical period a little milk or bu t te rwere added to the experimental diet, the ra t s quicklyrecovered, and normal development ensued.

Shortly afterwards, Osborne and Mendel 305 supplemented

T H E FAT-SOLUBLE COMPLETTIN A 221

their previous observations by finding that fat-free milk,and also the salts contained in the water of butter, werequite ineffective ; bu t tha t perfectly pure butter fat, obtainedentirely free from nitrogen and phosphorus by melting andcentrifuging the butter , was a very active growth-factor,greatly superior to lard. This report was promptly con-firmed by McCollum and Davis 386; and Osborne andMendel 350 were able to detect the active principles in thefat of yolk of egg and in codliver oil, but could not findit in almond oil.

Opposed to these reports was one made by D e z a n i ^who found tha t he could keep his experimental animalsalive and in good condition on a lipoid-free diet, providedonly tha t the diet were sufficiently varied. He contendedtha t what was wrong with Stepp's experiments was tha tt he monotony of the diet had induced loss of appetite inthe animals subjected to experiment. We know to-day tha tDezani's inferences were fallacious to some extent, inasmuchas his experimental diet, though free from lipoids, was notfree from the complettin A. Almost simultaneously withthe Italian's paper there came from two widely divergentsources confirmations of Stepp's observations. Kawashina,4*7and McArthur and L u c k e t t w who reported along almostprecisely the same lines, were able to show that the variouslecithins, other lipoids, cholesterins, and fats, are not essen-tial to life in mice [this is true, provided that the supply ofprotein is adequate] ; bu t that , on the other hand, a dietconsisting of casein, starch, lactose, lard, and milk salts,incompetent per se to maintain life in mice, could berendered fully adequate by *the addition of a substance presentin yolk of egg and soluble in alcohol and ether.

An investigation made by Funk and Macallum 374 showedtha t the life-sustaining substance could not be identicalwith butter fat, for the addition of a thoroughly purifiedsuperheated bu t te r fat could not render adequate a dietlacking only in the one factor under consideration, whereasthe alcoholic extract made from the original butter was per-fectly competent to render the diet adequate. Halliburton 73*therefore considers tha t the reason why fats are indispensableto life is that they contain this growth-complettin.

222 VITAMINS

Nevertheless, as we learned above, a large number ofother investigations had shown tha t there is another factor,the water-soluble complettin B, no less indispensable forthe maintenance of life and growth. Since there is little ofthis complettin in fats, or none a t all, it was natural to sup-pose that green vegetables, etc., were to be looked uponexclusively as the providers of B, and tha t A was presentonly in fats. Hence the two substances have been fre-quently confounded (cf. 714). But it soon became apparenttha t certain nutrients that were unquestionably rich in B,could only maintain growth when supplemented with A ;and that others, such as green leaves, though free from fat,were adequate growth-factors without any addition of A.»35

By a large number of investigations it has now beenproved beyond dispute tha t for the maintenance of body-weight and for the promotion of normal growth both A andB are essential.453,454,874, «84,1045 More especially has thisbeen demonstrated by the work of McCollum and Sim-monds,66l> 664 who simultaneously showed tha t both thegrowth-complettins were subject to the law of the minimum.

2. OCCURRENCE.

The occurrence of A was first definitely proved in rnilk,and its presence in this fluid has subsequently been con-firmed by numerous investigations.**^ **7. *9S> 305* 3**# ?8|» n%9With the separation of the cream, the greater part of the Afactor passes away into this *95> y>$. 35°, 3 , w. 7%*, *M* ; andwhen the cream is made into butter, the A is chiefly storedin the more fluid portion, the so-called butyric oil 3°5» 4*4, 477;but considerable quantities of A remain in the skim-milk,and when the casein is precipitated they are included in theprecipitate. Both the casein of commerce, and also chee$e,7Mtherefore invariably contain A, though in small quantities,so that neither casein nor cheese must form a componentof an A-free diet. Yolk of egg, the first source of nutrimentfor the growing bird embryo, is very rich in A, for the fatof egg-yolk contains A in a concentrated form*35»« 5*6* 7**>i«9,1x46 j n the normal body-fat of animals, in beef fat forinstance,4*4,618,75a there are also large quantities of A,which, as in the case of butter, are stored in the ingredients

THE FAT-SOLUBLE COMPLETTIN A 223

o f the fat that have a comparatively low melting-point (theso-called oleomargarine or olein 434, 618, 752) - whereas thestearin of animal fat, just like the part of the butter whichl i a s a high melting-point, is practically free from A.4*4 Con-sequently animal margarine, which is manufactured fromoleomargarine or olein, is comparatively rich in A,61®* J3*9

In contradistinction to the normal body-fat, the storagef a t of animals contains very little A.75*. XM3 For this reason,lard is very poor in A ; 305* 374,386, 434. 453, 454, i%*, 13*7 but it isnot, as was at one time believed, completely free fromA.IX4^ 13*6

The fat of fish, like the fat of mammals, is rich in A, sothat fish oils in general contain an abundance of thiscomplettin.6^

Passing to consider the individual organs, we find thatthe pancreas, the thymus, and the adrenals, contain com-paratively little A 9™; whereas the kidneys contain more,the heart still more,43^ and the liver most of all. Conse-quently the oil expressed from pig's liver is as vigorous inits growth-promoting qualities as butter 7<>*; and at anearly stage in this investigation codliver oil was recognisedas preeminent among fats for its richness in A.35°, 374, 634, 781, 1146

In contradistinction with eggs, the seeds of plants usuallycontain too little A to ensure the maintenance of normalgrowth. In especial this has been proved as regards oats,6*5, 7*4wheat 436,515, 68a, ?I4> barley 74©, rye 7*4, and maize 4361 57», 658,***, 714. According to Steenbock, Boutwell, Gross, andSell,I0*7 yellow maize is an exception, for 88 % of this inthe food suffices to maintain growth in young rats. McCollumand his collaborators^8 however, found that the A contentof yellow maize was inadequate to promote growth in pigs;but normal growth could be ensured in these animals if themaize were supplemented by an alcoholic extract fromanother portion of the same maize, this increasing the Acontent a little. Speaking generally, the cereals are inade-quate 490.68a j the germ contains a good deal more A thanthe endosperm and the bran,43^ 490 but not nearly enough.5°7Beans are very poorly supplied with A,63*, 658 this statementapplying to soy beans 659,*65 a n <i earth-nuts6**. "*9; butthere are certain pulses that contain fairly adequate quan-

224 VITAMINS

tities>«5 Brazil nuts, butternuts, Barcelona nuts, walnuts,and almonds, un* all \unn m A ; in like manuei, almondoil,3S« olive oil,7H| nut uill*

n «cK«*aimt oil,*'* and ccuo«mutcake, an: incompetent to in.iint.iin growth.*;* ( ottuit herdsare poor in A S - J * 7 M ; ami MJ, then Urn*, is cottonseedojl/*jK, 1146 Since tottonsu' i l oil and couMnut oil are thechief constituents of vegetable iuatf{.inne*, tht*e hkewi.searc inadequate as ^icAvth f.u tuis/*** Un *!'*' other hand,linseed, millet, ami hemp set cLs*'* ate iepr*ittd tu be fairlyrich in A, although the quanti ty is inadequate?* <« ***

Fiuit would appear in general to be v u y poorly Mjppliedwith the fut-sohible ^niwth-tf^niplettm. kspc-nuUy is thin re-ported of bananas,?:^ oranges,11^ lemons and graj»e (imt.'M?

In respect of A content, sn-ds rontiast w t h leaveswhich arc, generally speaking, lirh m A.?1*. t«»n, n»i Thiw,

^ whitu cabba^e.i'/^ M« ami e q u a l l y gnen cal>spinach, (lover, and timothy j*r«»ss/j* are

as very rich, (hun t i t a t ivc iltid an* gjvnt by SGross, and Sell,tf»M whu tell n* that 5 % of lu*i »u% clover,spinach, an<l aitichoke leave,, or in % of white let tun*, inthe food, will suthte to en stair ntinnal growth and repioduc*tion in xats ; but evi:n 15 % ui white cabbage piuves mack-quate, Osborne ancl Mendd «u* fuumt that ty?natm*s weremore active than an erjual wnght ui but ter fat, and thatclover, lucerne, glass, and spinach were no Itv* active* Driedwhite cabbage was less active.

As regards rtiot crop-, j*oUtm<N> proved qutlr inatU*t)uatein this respea m* hi< ***** *M* ; but the swtnt ]n4atci, theAmerican rival of the jxitato, was just as artivi: an theextremely active carrut v*« Aao id ing tu Ztlva/1** carrotsare richer than white c.ibbai;**; but StttttUfck, tiru\%§ andSell found that turnips, niang<I*wtim*h# mgm hrrU, Artirnmaculatum (IOICK and ladirs), paiM4i|»# Hud €omiii«^n beetrootwere quite i

j , fottl'M'.TTlN A AKI>

We see, thcti# that although the complettm A t*in fat, the aunnount of t h b siikstanci: in v^nouji nutrients isby no means proportional to their m l w r * in fat^ At i nearly itage in these invoi iga t iont , the opinion gained ground

T H E FAT-SOLUBLE COMPLETTIN A 225

t h a t the re was a definite ratio between the A content andt h e lipochrome content of food, the belief being tha t then u t r i e n t s richest in lipochrome were also richest in A.I0*7Carro t s , which are among the most highly coloured of ther o o t crops, are especially rich in both A and lipo-chrome.784, 98l> K»7 The careful investigations of Rosenheima n d Drummond "3* have shown, however, that althought h e r e is a general parallelism in the A content and thel ipochrome content of nutrients, the parallelism is notinvar iab ly sustained:—

Foodstuff.

Milk Fat . .Yolk of EggCodliver OilWhale Oil . .Beef Fat . .Kidney FatMaizeWheat GermCabbageSpinach.CarrotsChicken FatLiverHerringsCottonseed OilCodLardCocoanut OilHardened Fats .

LipochromeContent.

4 - 4 - 4 -4 - 4 - 4 -4 - 4 - 4 -

4- 4-

4-4-

4- 4-+ 4-4- 4-

4" 4*4* 4"

A Content.

4 - 4 - 4 -4 - 4 - 4 -4 - 4 - 4 -

4- 4-

4- +4-

4- 4-4" +

-j-4- 4-4- 4-4- 4-

———

T h e hardening of fats seems to destroy the growth-com-p l e t t i n A ; and when fat is extracted with benzin or withe ther , most of the complettin is removed by the process.11^

J u s t as in the case of water-soluble B, so also in the caseof fat-soluble A, the richness of the natural nutrients isincons tant . I n especial, this has been proved as regardsmi lk and but ter by Steenbock, Boutwell, and Kent.75* Theseauthor i t ies suppose tha t the chief cause of the variationsm u s t be the different feeding of the cows, bu t i t appearst h a t the same fodder will contain different amounts of Aa t different times. Consequently, in the case of fat-solubleA as in tha t of water-soluble B, we have to reckon with

15

2 2 6 VITAMINS

seasonal variations in the richness of the pastures. F u r t h e rmore, as we are about to learn, when dried fodder is inquestion, prolonged storage of the fodder is at tended wi th adecline in the A content.

4. RELATIONSHIP TO OTHER COMPLETTXNS.

Among the descriptions of the properties of t he com-plettin A we find several inconsistencies, which might leadus to suppose t h a t we really had to deal with different sub-stances in the different nutrients. A more careful examina-tion shows, however, tha t the inconsistencies are main lydue to the great comprehensiveness of the researches con-cerned with the complettin A, and that in some of thesethere has been confusion with the other complett ins—moreespecially with the complettin B. In the early stages ofthe investigation, the inclination was to regard A as a lipoid,and we have already learned that this was Stcpp's originalopinion.526 But Osborne and Mendel 3°5 have proved (cf.also 7J4,875,1308) tha t the substance must be free from nitrogenand phosphorus, or tha t if it contains either or both, it mus tdo so in quantities t h a t are almost incredibly minute ; obvi-ously, therefore, i t cannot be a lipoid. As regards o the ringredients of the fats, subsequent investigations 7*1* •?$• *J*have shown beyond dispute that A is not glycerine, t h a t i tis not a saturated or unsaturated fatty acid, and t h a t itis not an undecomposed f a t ; nor can the various sterins b eaccounted possible incorporators of the A influence, i n t h eforegoing chapter (p. 204), we learned, indeed, tha t the s te r inshad the opposite effect to A, inasmuch as they interferedwith growth, especially when given in excess. Funk 375 w a sat first inclined to believe that A must be a base having asimilar action to tha t of the vitamins. But Stepp has givenadequate prc>of,5*7 first of all tha t A contains no ni t rogen,and secondly tha t i ts mode of action is quite different fromthose of the v i tamins ; Funk and Macallum have confirmedthis view>4 The researches of Rosenheim and Drum-mond«3* have shown that A, despite i ts kinship wi th t h elipochromes, is not itself a lipochrome; and this h a s b®eaconfirmed by numerous authorities^,959* $&>, 9&*> 1*70, *i*3 I tremained to be demonstrated tha t A and E were d is t inc t .

T H E FAT-SOLUBLE COMPLETTIN A 227

The distinction is, in fart, obvious, for we know of substances(like butyric oil) which contain A and hardly any H ; andof others (turnips, potatoes) which contain B and no A.Furthermore we find that A without B or H without A doesnot suffice to render a diet adequa te ; also, tha t the effectsof the two differ greatly in certain respects -for instance,A prevents and cures* xerophthalmia and osteomalacia,whereas B does not. Finally, the question has to be mootedwhether A might not l>e identical with the antiscorbuticcomplettin C. Apart , however, from the consideration tha tthe effects of A and C are entirely different, direct proofthat the two substances are distinct has been furnished byGivens and Cohen,7*i Harden and Zilva,*»s and Mellanby.11**We are therefore constrained to admit that the romplett in Ais a distinct substance, not identical with any of the otherrecognised growth-promoting or life-sustaining substances.We shall now proceed to consider tin* properties of A,excluding reference to any properties that might be asciibedto confusion with other substances, or to impurities.

5. PftOPl-KTIKS OF THM OOMMJiTTIN A,

In 1009, Stepp** drew attention to the solubility of thiscomplettin in alcohol, ami the fact lias been confirmed byall subsequent investigators,ft** «f* ***< w* *»*• 7M* ***h 1150 Itis but slightly soluble in water#?M and cannot be extractedfrom fat by water.11?$ I t is, however, soluble, (though notvery readily) in the* ordinary fat solvents acetone,*** benzol,chloroform,1 M» ami cither,**?, w* ***• v%, 114* but cannot \mcompletely extracted by these* menstrua. When, however, Ais first extracted with alcohol, and the extract is evaporateddown, the complettin cm then be fully extracted from theresidue with ether. Thin provides a good method of purift*cation. For example, green vegetables, having been driedand pulverised, are treated with brnzin or with cither toextract tha f a t ; the complettin h then extracted withalcohol; when thit alcohol hm been evaporated off, theresidue is extracted with e t h e r ; when the ether ha* beenevaporated, the complettin i% left in a fairly pure atate. Fordietetic experiments it can then be dissolved in olive oilwhich has been previously freed from A, (Cf, Zilva, 1150*)

2 2 8 VITAMINS

Speaking generally, however, the complettin A (though speci-fically termed "fat-soluble") is not readily dissolved byfats, and cannot be extracted from vegetable nutrients byvegetable oils or by lard.7*4, "4*

Funk and Macallum374 began by isolating A by themethod then in vogue for the isolation of vitamin, namelyby extraction with 0 - 5 % hydrochloric acid; but obviouslyall they could get in this way were specimens of A contain-ing vitamin as impurity—this being, indeed, manifest fromthe other data of the investigation. Drummond 875 declares,moreover, that A is almost insoluble in hydrochloric acid.The non-identity of A with vitamins, with B and with D,and above all with C, is best shown by the reaction of therespective substances to alkalies. Whereas the other com-plettins all appear to be more or less sensitive to the actionof alkalies, A is apparently unaffected by them. Steenbock,Boutwell, Gross, and Sell IX4* actually declare that fats con-taining A can be fully saponified by 6 % alcoholic solutionof potash without the A being notably affected, even thoughthe action of the alkali has been continued for several days.Drummond,875 however, tells us that there is a certain lossof A in this process, perhaps due to oxidation—see p. 229.By shaking up the soap solution with ether and evaporatingoff the ether, an extremely effective residue was obtained.This could be further purified by dissolving it in a mixtureof alcohol and petroleum ether (naphtha), and then addingwater, shaking up, and allowing the solution to separate-into layers. The A, together with the carotin, passed intothe naphtha stratum, whereas the alcoholic xanthophyllsolution contained no more than traces of it . This reportsuggests that the obtaining of A in a pure state ought to bepossible, and it could be wished that with this end in viewthe physiologists would seek the aid of a competent chemist.

As regards thermostability, the complettin A differsgreatly from the complettins hitherto considered, and alsofrom C. Nevertheless, as Osborne and Mendel 702 andRamsden7i4 insist, the power of resisting heat is greatlyinfluenced by the conditions under which the heat is applied,one of these conditions being the nature of the menstruum.Thus Mendel I223 reports that A in butyric oil is less resistant

T H E FAT-SOLUBLE COMPLETTIN A 229

to heat than A in aggregate butter. In butter, A will resistlong-continued steaming^w, 113* fifteen hours' heating at95° C-,lliz and even four hours' heating at 1200 C.IO34; buti t is destroyed by longer heating at these high tempera-tures.396, 427 Yet Steenbock, Boutwell, and Kent 75* foundtha t when butter was shaken up with hot water for a longtime, the A it contained was seriously injured; and theyconsidered that the injury was due to the effect of heat.Stepp 334 reported tha t two days' boiling of the active lipoids,or of the aggregate food, in alcohol, or more prolonged boil-ing in water, destroyed the activity of the substance.

According to Delf,8°6 the growth-complettin A in greencabbage resists ordinary boiling, but it is somewhat impairedby keeping the dried cabbage for from one to two hours ata temperature ranging from ioo° to 1200 C , and is veryseriously injured by two hours' dry heating at 1300 C. Onthe other hand, Steenbock and his collaborators IO54 informus tha t the A in green cabbage is not affected by threehours' heating in the autoclave under fifteen pounds pressure.

The contradictory character of the foregoing reports ismainly explicable by the supposition tha t the complettin Ais readily oxidisable. According to Drummond,875 when thefood containing A is heated in thin layers to ioo° C , the Ais destroyed within an hour, whereas several weeks' exposureto a temperature of 370 C. is requisite to effect destruction.Subsequently, Drummond and Coward X3*4 gave direct con-firmation of the hypothesis tha t the cause of the destructionmust be oxidation by atmospheric oxygen. This, likewise,is the plain inference from the experiments of Hopkins, IO34who found tha t four hours' heating of butter at 1200 C. hadno deleterious effect upon the A it contained, whereas the Awas completely destroyed within the same period at thistemperature when air was forced through butter all the while.I n a subsequent and extensive series of experiments,^^Hopkins confirmed the theory that A is readily oxidisable.According to Zilva,x3*5 ozone, even in the dark, speedilyrenders A completely inactive; and ultraviolet light willquickly destroy A in codliver oil when air or ozone is present,but has no effect when the oil is in a carbonic-acid atmo-sphere. The sensitiveness of A to light was pointed out in

23o VITAMINS

1918 by Ramsden,7I4 who did not, however, recognise thereal bearing of his own observation.

We may, therefore, assume that when air is excluded,or when a nutrient is heated in compact masses, the com-plettin A will tolerate even prolonged heating a t I2O°C.under atmospheric pressure or under greater pressure. Butwhen air has free access (either because the nutrient is heatedin thin layers, or because it has been pulverised, or becauseit is in dilute solution, or because air is directly conductedthrough it), A is speedily destroyed by a high temperature.This explains why it is that when lactalbumin 898 o r casein I I68

is heated at 1200 for a long time in thin layers, the traces of Athese substances contain are destroyed, and yet t ha t but ter canbe exposed to the same conditions without appreciable loss of A.

We can also understand why the drying of vegetables,especially when the drying is effected in the customarymanner at a moderate temperature,1^*, 13** i s harmless tothe A they contain, and that the dried material can safelybe stored in large masses with the exclusion of a i r ; butthat when the A-containing substances are preserved in thepowdered state, and especially in open vessels, the com-plettin A is soon destroyed.80? This explains, likewise, whybutter can be preserved in bulk for years without the lossof efficiency of the A it contains, whereas butyr ic oil nolonger contains any effective A after a year's storage.477Delf and Skelton *>7 describe the drying of vegetables as anundesirable method of preserving t h e m ; but the foregoingconsiderations will show that, as far as the A content is con-cerned, this is true only if the dried vegetables are freelyexposed to the action of the air.

6. PHYSIOLOGICAL ACTION OF THE FAT-SOLUBLE

COMPLETTIN A.

When there is a deficiency of A in the food, jus t as whenthere is a deficiency of B, the first effect is an arrest ofgrowth (in young animals); then comes a rap id loss ofweight, often attended with grave debility,821* IX33 and theappetite falls off. The general debility and the lowering ofthe resistance to infections is even more marked when thereis a lack of A than when there is a lack of B. The power

THE FAT-SOLUBLE COMPLETTIN A 231

of A to enhance the resistance of the organism to microbicinfection is extremely characteristic of this complettin.8?6*920, 1116 The difference between breast-fed and bottle-fedinfants as regards resistance to infection is well known;Aron refers this to the high A content of the natural milk.The same authorityI1I7> suggests that the extreme prevalenceof influenza during the last years of the war, and the malig-nancy of the disease at this epoch, may have been due tothe general lack of A in the diet, and to the consequentweakening of the constitution.

When there is a deficiency of A in the diet, just as whenthere is a deficiency of B, no change can be detected in theserological cons tan ts .^ We must therefore look to a directloss of efficiency in the organism or its cells to account forthe diminished powers of resistance. No doubt one of theeffects of wartime feeding was the widely noted diminutionof the haemoglobin richness of the blood ; bu t war feedingwas defective in so many respects that we are hardly justifiedin laying the blame upon one defect in particular. Stepp 884certainly found tha t in dogs fed on an A-free diet there wasa marked decline in the haemoglobin richness of the blood,although the number of the erythrocytes remained normal.Dalyell,IO55 in a Viennese child suffering from grave mal-nutrition, found that the provision of A in the diet was fol-lowed within two-and-a-half months by an increase in thehaemoglobin richness of the blood from 38 % to 70 %.

The effects of A and B in respect of growth are of coursemanifest only in growing animals, and in like manner theeffects upon body-weight are far more manifest in youngthan in adult animals—more manifest in proportion to theactivity with which growth should be proceeding.459 Wefind also that the effect of A deficiency in reducing resistanceto infections is less marked in adul tsJ^ Nevertheless, A isessential to adults for the maintenance of body-weight anda good general condition.^*

7. A IN RELATION TO XEROPHTHALMIA AND TOKERATOMALACIA RESPECTIVELY.

The lowering of resistance to infection gives rise, especi-ally in youth, to an aifection of the eyes which may be

232 VITAMINS

regarded as pathognomonic of A deficiency. This diseaseis known as xerophthalmia, which usually passes on rapidlyinto keratomalacia. Of all the tissues of the animal body,the cornea is perhaps the most completely removed fromthe direct influence of the blood stream, and it is thereforeonly to be expected that any important change in the bodilyjuices should speedily produce effects upon the cornea. Thelack of A in the food gives rise to a' general dryness of theskin, and it has similar effects upon the cornea. The morbidstate thereby induced makes it easy for all kinds of microbesto invade the tissues of the eye, producing changes whichmay culminate in blindness. The occurrence of xerophthalmiain A deficiency was first noticed by Freise, Goldschmidt,and Frank 459 in rats fed on food which had been extractedwith alcohol. The observation was confirmed by Bulley,821

Hopkins,1066 and Nelson and Lamb.JI43 The primary causeof the disease is not the infection of the cornea, but the dry-ing of the cornea through the lack of A, which prepares theground for microbic invasion. Bulley has repeatedly endea-voured to infect with material from cases of keratomalaciathe eyes of rats fed on a diet rich in A, but has never suc-ceeded. Or rather, among 250 young rats on an adequatediet, 5 only became affected with xerophthalmia, and inthese instances there was reason to suppose that the extremeuncleanliness of the animals was the cause of the infection.On the other hand, rats fed on a diet devoid of A almostinvariably became affected with xerophthalmia or kerato-malacia.

Among diets especially prone to induce these diseases ofthe eye, the following ill-balanced diets are mentioned:potato d i e t 8 l 2 ; nuts poor in A Il69 ; cereals 682» 796;—evenwhen supplemented with buttermilk, skim-milk, or vegetablemarga r ine s Millet and hemp seeds are said by McCollumand Simmonds683 to prevent the onset of xerophthalmia;but according to Auer,81* attacks may occur when millet isbeing given. We may assume tha t in millet, as in othernatural foods, the quantity of A is variable; and since thereis at the best but a narrow margin of sufficiency in thisgrain, the amount may fall below the necessary minimum.The same considerations apply to skim-milk, which will

THE FAT-SOLUBLE COMPLETTIN A 233

contain very little A if the removal of the cream has beenthorough. This explains the discrepancy between the obser-vations of Bloch,9*o who found that a diet of buttermilk orskim-milk may induce keratomalacia in children, and thoseof Freise, Goldschmidt, and Frank,459 according to whombuttermilk and skim-milk will cure the disease.

When the diet is rich in A (when, that is to say, it con-tains plenty of butter, cream, full milk, eggs,92o or codliveroilI057), this affection of the eyes is rarely encountered, andthen only as a result of general debility and deficient atten-tion to cleanliness. Perhaps these exceptional instancesmay also be referred to a deficiency of inorganic salts in thediet, for McCollum and Simmonds68* draw special attentionto the fact that , while A can prevent or cure the disease, itcan only do so when the diet contains an ample supply ofsodium and potassium.

For the cure of xerophthalmia or keratomalacia, extractsrich in A,I243 and natural nutrients rich in A, such asbutter,682* 9*°> IO55 cream, full milk, eggs,9*> and codliveroil,9*°, r°55 will be found valuable; the same substances areefficacious as prophylactics.682* 7*4. 812, 821, 1343, 131*

8. A IN RELATION TO OSTEOMALACIA.

Like the cornea, the cartilages and the osteogenic tissuesare poorly supplied with blood, and they too therefore areespecially apt to suffer when A is lacking in the diet.IO55 Inexperiments on animals, changes in the bones are less con-spicuous than changes in the cornea, so that reports uponbone disorders are rare. According to the experimentsmade by Mellanby IO55 in the years 1918 and 1919, youngdogs supplied with a diet poor in A but otherwise adequatebecome " r ickety" ; but the author's descriptions suggestrather the onset of a rachitis tarda, which may be regardedas identical with osteomalacia. According to Barnes andH u m e ^ the chief characteristic of this disease is a rare-faction of the osteoid tissue, which in the neighbourhood ofthe epiphyses may be reduced to the thinness of paper ;the spongy tissue may more or less completely disappear,but the chemical composition of the bone is not affected.In true rickets, on the other hand, there is softening of the

234 VITAMINS

bone tissue with a predominant loss of calcium salts, so thatthe bone-ash in cases of rickets exhibits an abnormal prepon-derance of magnesium salts.

Weiser,347 feeding pigs on an exclusive diet of maize,noted the onset of " ricket-like " diseases of the bones, andhe considered that rickets was actually present. I t is truethat in the experimental animals there could be detectedin the canial bones, the ribs, and the vertebrae, a moderateincrease in the proportion of magnesium, and that this obser-vation might be taken as confirming the rickets theoryBut in rickets the most pronounced changes occur in thebones of the extremities, and in the experimental animalsthese bones contained a normal percentage of magnesium—or in some instances even a little less than normal. Wecan, therefore, confidently infer that the disease was notrickets, but osteomalacia.

Scheunert, Schattke, and Lotzsch l S l reported the onsetof a similar disease in horses fed on hay of abnormal com-position. They considered that the unusually low propor-tion of lime and phosphorus in the hay was the pathogenicfactor, and we know that in abnormal vegetable productsthe A content may be too low. Scheunert Io88 has recentlyreported another case in which osteomalacia occurred inhorses fed for ten years in the same stable. In this instance,the fodder was normal as regards richness in inorganic salts,and the only obvious defect in the diet was that the drinkingwater was very poor in calcium. Scheunert thinks tha t theillness was due to an infection of the stables and the drinkingwater with a diplococcus which gave rise to digestive dis-orders in the horses, resulting in a general modification ofthe intestinal flora and in the abundant formation of lacticacid in the intestine. Both these instances are extremelyinteresting in more ways than one, and I shall return totheir consideration shortly.

During the later years of the war, osteomalacia and otherforms of osteopathy were frequent, and in the large townssometimes assumed epidemic proportions. This tends toconfirm the opinion tha t the complettin A is essential tothe normal metabolism of the bones. I t has been widelybelieved that the cause of these troubles must have been

T H E FAT-SOLUBLE COMPLETTIN A 235

some lack in the diet, especially a lack of calcium and phos-phoruses, 9<>5, 1031, 1078, 1290,1306 fcut other authorities havespoken of a " lack of vitamin." 933,1078 The latter assump-tion is confirmed by the following considerations. First ofall, the bone disorders were frequently associated with signsof disorder of the endocrine glands, such as amenorrhoea inadult women and a failure of menstruation to begin in girls atthe age of puberty (cf. Blencke IO78), and by nervous symptoms,such as tetany and other spasmodic troubles.1^, 1165 Inthe second place, the diseases were curable by a diet richin A, and especially by the administration of codliver oil933, 1078 or of phosphorated codliver oil.933,96s, J3<>6

9. A IN RELATION TO RlCKETS.

Obviously, the onset of such bone diseases when thediet is lacking in A, in conjunction with the specific anti-rachitic effect of codliver oil (a substance rich in A), hasgiven rise to the view that rickets is caused by a deficiencyof A in the food. Osborne and Mendel 35° (see also Aron 781),who were the first to discover that codliver oil contains A>

promptly thereon gave expression to the opinion that thetherapeutic value of codliver oil in rachitic disorders mustbe due to the A it contained. The suggestion received addi-tional support when it was found that osteomalacia wasprone to arise when the diet was deficient in A. But thehypothesis has never secured unconditional acceptance amongexperts, R6hmann47* considers that the main cause ofrickets is, either a lack of calcium in the food, or inadequateabsorption of calcium by the intestine, " with the possiblecollaboration of " a disturbance of the honnonic secretionsthat control the formation of bone. McCollum, Simmonds,and Parsons,^1 and also Dalyell,I338 while admitting tha t thelack of A has some causative influence in the production ofrickets, nevertheless regard this influence as subsidiary,and stress the importance of other errors of nutrition (not-ably, the lack of B, C, calcium salts, and phosphorus), toge-ther with the significance of the general conditions of lifeand tha t of the care of the body. As regards the diseasesof bone that occurred in Mellanby's dogs,IO55 it is evidenceagainst the presumption that they were rachitic, tha t a cure

236 VITAMINS

ensued when butter or full milk was added to the animals 'diet for in children suffering from rickets, the administra-tion of full milk in the absence of codliver oil is apt t o makematters worse.

At first, misunderstanding arose in these investigationsthrough the reiterated confusion between A and B inplants.IJ35 But the further research went, the m o r e wasdoubt cast upon the accuracy of such views. I n 1920Mendel himself said that he considered it dubious whetherA really had anything to do with the causation or c u r e ofrickets I 2 2 3 ; and Mackay, an authority on the diseases ofchildhood, has expressed the same view.3^*8 I t is a familiarand indisputable fact that codliver oil has a specific effect bothin the prevention and in the cure of rickets.IO35> 1057, I369* e tcBut it is probable that the value of codliver oil maydepend upon factors of an unknown nature, factors whichhave no connection with the A content of the oil. Borderingon the absurd is a statement by Hamshire and Hawker 9J4 tothe effect that rickets can be cured by a proprietary prepara-tion " r i ch in vitamins," known as "University C r e a m / 'and consisting of beef suet, olive oil or earth-nut oil, syrup,benzoic acid, and decoction of Irish moss.

In 1920, the British Medical Association held " A Discus-sion on the present Position of Vitamins in clinical Medi-cine," I05S which served to clear up the problem a good deal.Whilst Hopkins expressed the opinion that the fat-solublefactor, though not (by its absence) the sole cause of r ickets ,was certainly an important etiological factor, and whilstHess looked upon Mellanby's discovery as very impor tant ,Hess himself insisted that a number of other factors bothorganic and inorganic must play a part in the pathogenesisof this disease. Many mistakes had arisen from confoundingslight cases of scurvy and other affections with incipientrickets. Still insisted upon the indispensability of t h e fat-soluble complettin, but reported tha t milk which h a d beensterilised by the addition of hydrogen peroxide and w a n n i n g—being thereby freed from A—induced in children notrickets but scurvy. Mann likewise regarded rickets a s theoutcome of a complex of causes, the chief of which w a s adearth of fat in the diet. (Why then do infants fed o n full

T H E FAT-SOLUBLE COMPLETTIN A 237

milk become rickety ?) Pritchard spoke of numerous factorsas contributing to the causation of r ickets: defect or excessof one or other constituent of the d ie t ; lack of fresh air orbodily exercise; chronic infections, especially of the gastro-intestinal tract. All of these combined to increase the needof the organism for calcium, so that the supply to the grow-ing cartilages was insufficient.

To anyone thoroughly well acquainted with the condi-tions under which rickets arises, these views are obviouslyfull of contradictions. First of all it has repeatedly beenshown that human nurselings often become affected withrickets even though their food contains plenty of A. Again,it has long been known that in cases of incipient rickets,the presence of a superabundance of calcium in the fooddoes no good unless codliver oil be simultaneously admi-nistered. Finally, even though the diet is persistently poorin calcium, codliver oil can cure rickets, although the cureis certainly expedited by the simultaneous administration ofcalcium salts, and especially of soluble tricalcium phosphate.All these circumstances have been expounded in masterlyfashion in the writings of Herbst and of Schloss. In especial,the last-named author, whose premature death during thewar is profoundly to be regretted, has given an extraordi-narily clear and vivid picture of the disease. He describesrickets as a constitutional affection of the osteogenic tissue,whereby not merely is the growth of the bones hindered,but, further, the deposit of calcium salts in the osteogenictissue is interfered with by a reduction in the affinity ofthis tissue for calcium salts. The specific effect of cod-liver oil consists in a stimulation of the affinity until i tattains a normal or even a supernormal level, so tha t theosteogenic tissue is rendered competent to assimilate withthe utmost energy the available calcium, even though thisbe presented in very small quantities.

These epoch-making writings of Herbst and Schloss,which for the most part appeared during the war, have notreceived sufficient attention from British medical authorities,who are rather inclined towards conservatism. But whilethe failure of the British in this respect is excusable, I findit impossible to excuse the German faculty for its neglect

2 3 8 VITAMINS

of these remarkable contributions of Schloss and Herbs t .I t seems to me characteristic of the mentality of my country-men that, while uncritically accepting foreign opinions, t h e yshould ignore the best productions of German science. I twould seem as if there were justice in the contention t h a tthere is an ebb in German science, and that the leadershiphas now passed to the Americans. A tragical outcome ofthe war, and perhaps for the German nation the worst ofall its outcomes!

To summarise the present position of our knowledge, i tis certain that some sort of inadequacy in the diet must b ea predisposing cause of rickets and a contributory factor i nmaintaining the disease. On the other hand, it is provedthat neither a liberal supply of A, nor a superabundance ofcalcium salts, nor both combined, can avail prophylacticallyor therapeutically unless codliver oil (which must not b etoo highly refined) be used as the vehicle for A. I t wouldseem, therefore, tha t the richness of codliver oil in A is amere accessory to the antirachitic action of this specific.The effect of codliver oil in rickets may be fortified by t h erichness of the oil in A, but must have other essential causes.In fine, the only certain prophylactic is breast-feeding by amother able to supply good milk.

10. A IN RELATION TO PELLAGRA.

No less uncritical than the contention that a lack of Ain the diet is the main cause of rickets, is the assumption ofMcCollum and his collaborators^1 tha t A deficiency is acause of pellagra. In Chapter Nine we shall show that t h i sassumption is untenable.

I I . A IN RELATION TO MALNUTRITIONAL OEDEMA.

Equally unsound is the contention of Hopkins that Adeficiency is important as an etiological factor in the produc-tion of malnutritional oedema. Chick "37 is also inclined t oregard a lack of A in the diet as one of the causes of mal -nutritional oedema; and according to McCarrisonIJ4<> t h enormal action of A is to keep down the adrenalin content.When the fat-soluble factor is deficient in the diet, t h eadrenals hypertrophy, and there ensues an excessive produc-

T H E FAT-SOLUBLE COMPLETTIN A 239

tion of adrenalin, leading to oedema. We discussed this theoryon p . 145, and showed there that it involved an inverted viewof the facts, and tha t McCarrison had withdrawn his con-ten t ion . 1 ^ Nevertheless, it is possible that a lack of A inthe diet may be a contributory cause of malnutritionaloedema. To this matter we shall return.

12. ACTION UPON THE ENDOCRINE GLANDS.

Though it seems probable that as regards the osteopathies,as regards the causation of osteomalacia and rickets, theimportance of the fat-soluble complettin has been consider-ably overestimated, its influence upon body-weight andgrowth has been definitely proved. This influence is fullyconsidered in Chapter Five, and all that is now requisite isto present a few important facts which are essential to thebetter understanding of the effects of A in the organism.We have seen tha t in growing animals and human beings,when there is a deficiency of A in the diet an arrest of growthensues; then comes a decline in body-weight, gradual atfirst, and subsequently rap id ; there is profound debility,which often proves fatal unless a speedier death should haveresulted from some intercurrent disease due to the lessenedresistance to infection and other noxious influences. Aconspicuous effect of A deficiency is a general atrophy ofthe endocrine glands, the only exception being the adrenals,which hypertrophy just as they do when there is a deficiencyof Funk's vitamin.876 The researches of Verzdr and Bogel IJ7°have shown that , like B and D, A is absolutely non-toxicalike in cold-blooded animals and in mammals, and that indogs affected with diabetes from operations on the pancreasneither the size of the pupils nor the excretion of sugar isaffected by their administration. But A differs from Band D in that i t has no effect upon the secretion of theglands. Consequently the atrophy of the endocrine glandsin A deficiency must be due to an interference with thenormal nutrition of these organs. The reduction in theirsecretion is merely an indirect consequence of the atrophy.

Verzdr and Bogel report, in addition, the interesting factt h a t A is a vasodilator, that it has an action antagonisticto tha t of adrenalin. All the more striking is it, then, that

240 VITAMINS

the adrenals should undergo hypertrophy when there is alack of A, for there would not seem to be any direct occasionfor a surplus production of adrenalin. The lack of A mustenhance the effect of the adrenalin, and the hypertrophy ofthe adrenals must be regarded as a direct consequence ofthe A deficiency—but the way in which this effect is producedis still to seek.

According to Drummond, the deposit of fat occurs inanimals quite normally when A is lacking, and the milk oflactating animals remains perfectly normal in respect of fatcontent 87$; but a sufficiency of milk for the growth andthe normal development of the offspring can only be secretedby the mother when her food contains an adequate supplyof A. The lacteal glands cannot themselves manufactureA ; but, just as they are able to call upon the maternalorganism, even at the cost of its own health, to supply allthe other necessary constituents of normal milk, so are theyin a position, when there is a lack of A in the diet, to com-mandeer whatever quantities of A may be circulating in thematernal blood and to secrete them in the milk. Accordingto McCollum and Simmonds,10*6 only when the lack of A inthe maternal diet has been long continued does there arise adeficiency of A in the milk, and the effects of this arepromptly manifested in the sucklings by an arrest of growth,by debility, and by a proneness to xerophthalmia.

The facts just recorded indicate clearly tha t the fat-soluble complettin A cannot be synthetised in the animalbody, and that the animal organism's need for this substancecan be satisfied in no other way than by its provision ready-made in the food.234, 56l> 10*t, XI7° The ultimate source ofthe fat-soluble complettin is, therefore, the vegetable kingdom.The main supply would appear to be derived from thegreen and growing parts tof plants, but in exceptionalinstances it is found in the stored-up fat.

The various yeasts and microorganisms are able to syn-thetise A for their own needs, and are therefore independentof supplies from without. Very interesting, therefore, isthe statement of Willaman IO43 (if correct), that certain fungi,and notably Sclerotinia cinerea, appear to need a supply ofA, being otherwise incompetent t o form spores. We must

T H E FAT-SOLUBLE COMPLETTIN A 241

assume that , just as in the case of animals (which are allparasitic upon the plant world), the parasitic mode of lifeof these fungi has led to a degeneration of the parasites inthis respect, so tha t they are no longer competent to satisfytheir need for A by independent production, and are com-pelled to draw upon the stores of the host.

In conclusion let me emphasise the fact that the effectof A is of course subject to the law of the minimum to thisextent, tha t when some other essential constituent of thediet is wholly lacking or is supplied in inadequate quantities,even the most liberal provision of A can have no effect. Asregards proteins, fats, and carbohydrates, and as regardsthe other complettins, the fact will be obvious to everyone.But people are so apt to overlook the importance of inor-ganic salts tha t I find it necessary to insist once more thatan adequate supply of these substances (adequate bothqualitatively and quantitatively) is an indispensable prere-quisite to the effective action of A. We have already seen 68a

tha t on a cereal diet a supplement of A remains withouteffect unless the inorganic content of the diet be likewisesupplemented by the addition of sodium and calcium untilthere is an excess of bases. In like manner, McCoUum andhis collaborators have shown I026 that , even when there isplenty of A in the diet, the maternal organism cannotsecrete sufficient milk, and therefore that the progeny cannotthrive, unless the mother's food likewise contain an adequateamount of inorganic salts in due proportions. Aulde 12S9 hasalso shown tha t a lack of calcium, when complettins are sup-plied, induces the same changes in the glands as those seenwhen the diet contains plenty of calcium but is deficient incomplettins. Similarly, although there be abundant A inthe diet, if calcium be deficient there will arise affections ofthe eye such as are witnessed when A is deficient; and incases of xerophthalmia, the administration of calcium inaddition to A will cure more quickly than will the admini-stration of A alone. The only possible interpretation ofthese facts is tha t the complettins cannot do their work inthe absence of the necessary inorganic salts.

16

CHAPTER SEVEN

T H E ANTISCORBUTIC COMPLETTIN C

i . HISTORICAL.

ALTHOUGH the nature of scurvy was not elucidated untilduring the last decade, this disease is one of the oldestscourges affecting mankind in northern latitudes. An exami-nation of skeletons dating from neolithic times, from thebronze age, and from the iron age, has shown that in Swedenduring those times scurvy must have been devastating inits prevalence, whereas rickets seems to have been almostunknown. During the long winters of those northern regions,when smoked or dried meat and fish constituted the s taplediet, it was inevitable that scurvy should be prevalent. A tthe present day, the Eskimos of North America live underconditions similar to those which prevailed in Scandinaviaduring the stone age—at any rate, during the paleolithic era,the greater part of Sweden was covered by an ice-sheet.Now, in summer the Eskimos, who live almost exclusivelyon flesh and fat, often suffer from a mild form of thehaemorrhagic diathesis, being affected with bleeding fromthe gums, nosebleed, haemorrhages from the other mucousmembranes, and severe extravasations of blood in the sub-cutaneous tissues upon comparatively slight provocation,while in winter, under the combined influence of famineand unsuitable diet, typical scurvy is apt to arise, sometimescarrying off entire tribes. Among the indigens of Nor th -Western Asia, who are at an even lower level of culture t hanthe Eskimos, and among the Ainos of Northern J a p a n ,similar conditions prevail. The rise of large urban com-munities in Northern and Central Europe, populations hemmedin by the walls and moats of the fortifications, gave occasion

24*

T H E ANTISCORBUTIC COMPLETTIN C 243

for long-continued epidemics of scurvy. The town-dwellerswere dependent for their food-supply upon the peasants ofthe immediate neighbourhood; and when there was anyarrest of the provision from this source, scurvy promptlymade its appearance in the cities. This was the rule as lateas the beginning of the nineteenth century. An examinationof the death registers of the old cities shows tha t scurvytook its place beside consumption and apoplexy as one ofthe most common causes of death.

When sea voyages grew longer, so that ships were monthswithout communication with the land, scurvy became afrequent and dreaded guest on board. The whalers, inespecial, who sometimes spent years in the far north underthe most unfavourable conditions, working very hard on anunsuitable diet, suffered greatly from the disease. So didthe men of the navies, who were closely herded together,and were fed almost exclusively upon badly preserved food.I t was natural, therefore, that upon ships the specific valueof the various sorts of lime and lemon as preventives ofscurvy should first have become known; and as early asthe sixteenth century, the antiscorbutic effect of fresh vege-tables was familiar. But it was not until the year 1796 tha tthe provision of lemons as a means for the prevention ofscurvy was made compulsory in the British navy.

We see, then, that it was no chance matter tha t theimpulse to the scientific study of this disease should haveoriginated in the north, and that the pioneer investigationsshould have been made in a land whose population has forthousands of years furnished so large a proportion of sea-faring men. In the year 1905, the Swedish physicianEkelof 47 expressed the opinion that the disastrous effect ofpreserved nutrients must depend upon the generation ofautolytic poisons within them. A little later, a similar ideawas promulgated in Germany by M. Schubert.51 Shortlybefore this, writing in the Swedish medical journal " Hygiea/ 'the Norwegian Schmidt-Nielsens© had amended the theorywith the suggestion that what happened during preservationwas not the formation of toxins, but the destruction ofimportant substances—enzymes, perhaps, or antibodies suchas were then becoming known in connection with the theory

244 VITAMINS

of immunity. Within the next year or two came the publi-cation by two Norwegians of the most important studiesincorporating the results of modern research into the natureof scurvy. In an extended series of experimental investi-gations, Hoist and Frolich have attempted, with the aid ofmodern physiological and chemical methods, to throw lightupon the etiology of scurvy.6** 63> *4,

6$> 10X> w l86> 20*> etc-First they were able to show tha t bread, cereals, or dried

potatoes, gave rise to scurvy in guineapigs; so did driedcabbage, dried carrots, and dried dandelion. On the otherhand, fresh fruits and vegetables, such as apples, potatoes,cabbage, carrots, dandelion, and lemon juice, can not onlycure scurvy, but when added to a scorbutogenic diet canprevent the onset of the disease. Peas, lentils, and almonds,and also maize, give rise to scurvy in guineapigs. Whennutrients which, as an exclusive diet, induce scurvy are givenin conjunction, the disease still arises, and this shows thatwe are not concerned here with a deficiency disease resemblingthat which occurs when an inadequate protein is given,seeing that several inadequate proteins respectively derivedfrom different classes of foodstuffs can compensate oneanother's deficiencies.102* l87» *°3 The addition of milk to thediet will prevent the onset of scurvy; but this prophylacticpower is more or less completely lost if the milk be boiled,condensed, or dried. In like manner, the prolonged boilingof such nutrients as cabbage, carrots, or dandelion, greatlyimpairs their antiscorbutic value.

The two Norwegian scientists inferred from their studiesthat quite a number of natural nutrients must contain anantiscorbutic ingredient. There are other nutrients in whichthis substance is present in small quantities only, or fromwhich it is entirely absent; and when such substances formthe staple diet, scurvy arises. The protective principle isthermolabile, and is rendered inactive or destroyed byprolonged boiling or by drying.

Another Norwegian, V. Fxirst,10** l87, 203, etc. confirmedand expanded these conclusions in a long series of investiga-tions. Notably, as early as 1910, Fiirst made the importantdiscovery that oats, peas, and lentils, which in the ordinarycondition are scorbutogenic for guineapigs, become during

T H E ANTISCORBUTIC COMPLETTIN C 245

germination so rich in the antiscorbutic complettin tha t theiraddition to a scorbutogenic diet can cure scurvy; and thatas exclusive diet these germinated grains or pulses are notscorbutogenic. He found, further, that in the germinatedseeds, likewise, the efficacy of the antiscorbutic complettinwas gravely impaired or completely destroyed by drying.Like Hoist and Frolich, Fiirst drew the inference that scurvymust depend upon the absence of a natural prophylactic fromthe diet. Since this substance is present in milk, which isa nutrient rich in vitamin, and since vitamin is rather sensitiveto heat, Funk assumed that scurvy must be akin to beriberi.*°5Numerous subsequent investigations, conducted by variousauthorities, have shown that the occurrence of scurvy mustactually be due to the absence of some protective principle.(Cf. in especial, 391, 7*4> ™M.)

Furst l87,203 had been able to exclude acidosis and infectionas possible causes of scurvy. McCollum and Pitz, however,now came forward with a new theory, according to whichscurvy was indirectly, though not directly, due to micro-organisms. They held that the causation of the disease didnot depend upon the lack of an accessory food factor, butupon prolonged retention of the faeces in the bowel, putre-factive processes, and consequent toxaemia.^1* 65* Pitz 693quotes an experiment by Lusk, who found that whole graindid not bring about scurvy in guineapigs; bu t McCollumfound that the addition of milk to a diet of whole grain inducedconstipation, and tha t the putrefactive processes which thenensued in the intestine gave rise to scurvy. Figueira,IO46

experimenting on guineapigs and dogs, came to the sameconclusion.

In support of this hypothesis, stress is laid on the assertionthat laxatives are said to prevent the onset of scurvy.^1* 65*> ^3The same effect is supposed to be secured by a modificationof the intestinal flora, leading to a replacement of putrefactiveprocesses by innocent fermentations ; in this way considerabledoses of lactose are said to prevent and cure scurvy.*93 Pitz,786

however, makes a reservation to the effect tha t althoughlaxatives and lactose can retard the outbreak of scurvy foras long as twenty weeks, they do not furnish completeprotection.

246 VITAMINS

Other authorities have been unable to confirm these data.Moreover, according to Harden and Zilva, large doses of thealkaline citrates are ineffective,794 although they destroy theorganisms of putrefaction and have a marked laxativeeffect; and according to the same investigators, the freeadministration of sugar, which has a similar action, is value-less.795 According to Hess and Unger,75<> laxative oils are ofno use as preventives of scurvy. Hart, Steenbock, and Smith?01

were unable to prevent the onset of scurvy by modifying theintestinal flora through the administration of chemicallypure lactose, or such laxatives as mineral oils or phenol-phthalein. Mouriquand and Michel IO23 likewise declare thatlaxatives are useless for the prevention and cure of scurvy.The same authorities found that in scorbutic guineapigs theintestine was often practically empty, and they concludedtherefore that stagnation of the faeces and intestinal putre-faction could not be regarded as the causes of scurvy. Onthe other hand, Karr and Lewis 638 have shown that in scorbuticguineapigs, even when constipation occurs, there is no increasein microbial activity within the intestine. Cohen and Mendel 749consider that retention of the faeces has no etiological relation-ship to scurvy, although naturally constipation, like anyother complication, can aggravate the symptoms of theprimary disease. Rohmann 473 would not admit the existenceof an antiscorbutic accessory food factor, and referred theorigination of scurvy to protein insufficiency. But this viewproved untenable when it had been shown tha t certainvegetable extracts which were absolutely free from nitrogenwere competent to cure or prevent scurvy.

I t is remarkable to find that McCollum, collaboratingwith Simmonds and Parsons,^1 has insisted that in the produc-tion of scurvy other causes must be operative in additionto the lack of A or B, and that Funk's vitamin has nothingto do with this disease. Aron, too, insists that the curativeeffect of fresh fruits and vegetables in infantile scurvy dependsupon the presence of water-soluble extractives.78* Willcox ioa5came to the same conclusion from his study of scurvy amongthe British troops in Mesopotamia during the recent war.Bierich,954 again, regards scurvy as dependent upon a denatu-ration of the food whereby it is rendered qualitatively inade-

T H E ANTISCORBUTIC COMPLETTIN C 247

quate. Quite isolated stands the report of Funk 5*7 to theeffect that antiscorbutics are valueless in guineapigs. Theanimals were being fed on oats, and Funk's experience of thevaluelessness of antiscorbutics is in such flat contradictionwith the experience of all other investigators that we areforced to assume the presence of some grave error of diet asa contributory factor—perhaps a lack of calcium. I t is, ofcourse, hard to believe that so noted and experienced aninvestigator can have made such a mistake, but this is theimpression left upon my mind by the secondhand referenceto which I have alone had access.

However, all the more recent researches point to the conclusionthat the cause of scurvy is a lack of complettin in the diet, andDrummond^U has christened the complettin specifically activein connexion with scurvy " water-soluble G."

2. SCURVY EPIDEMICS DURING RECENT YEARS.

Prior to 1914, people had come to regard scurvy as adisease belonging to obsolete stages of social evolution, asone of which civilisation had made an end. But the war of1914 to 1918, and the subsequent years of alleged peace, havefurnished plenty of opportunities for the study of scurvy onthe European continent, and notably in the armies. A fore-taste was provided in the last Balkan war, when scurvy wasrife in the Bulgarian army, although preserved vegetableshad been supplied as prophylactics. I have repeatedly hadoccasion to insist that these preserved vegetables wereprobably the cause of the disease. For the water-solubleantiscorbutic complettin, just like the excess of bases, isremoved by the " bleaching " process which (despite all tha thas been said against it by scientific authorities) is still invogue for the factory preparation of these preserves. Thusthe vegetables which were specially intended to preventscurvy, must have favoured the incidence of the disease.

Willcox I0*5 has published a detailed account of the epidemicof scurvy among the British troops in Mesopotamia. Inorder to prevent beriberi among the Indian soldiers, insteadof rice they were given " ata ," a barley flour containing agood deal of "bran and an abundance of vitamin, but poor inC. The men had no fresh meat, no vegetables, and no fruit,

248 VITAMINS

and the result of this diet was a severe outbreak of scurvy.The onset of the disease was favoured by the circumstancethat the men had already been weakened by the long seavoyage, were under-nourished, anaemic, and suffering (manyof them) from dental caries when they arrived a t the theatreof war. Doubtless, too, their powers of resistance wereweakened by the terrible climate, the uncertainty of theirfate, and the home-sickness which must have been accentuatedby the contrast between the Mesopotamian deserts and theirnative land. Willcox considers that the main factors of thecure were the supply of fresh vegetables and fruit and freshmea t ; and he states that a salad made with malt vinegarof raw, thinly sliced potatoes and raw onions was especiallyefficacious. He insists that the lack of complettin in thediet must have been the main cause of the disease.

I t is well known that, during the war, scurvy celebratedpositive orgies in Northern Russia, and the building of theMurmansk railway will be ever memorable in this respect.A British doctor, J . D. Comrie,1118 has given a detailed descrip-tion of the affair, and his account may be summarised asfollows. Among the Russian troops, scurvy was compara-tively infrequent, owing to the abundant supply of potatoes,pickled cabbage, fresh meat, and fresh fish; and among theBritish troops which, in accordance with the suggestions ofChick and Hume, were given germinated beans or peas asa prophylactic, the disease was exceedingly rare. I t was,however, terribly severe among the prisoners of war, whowere put upon extremely strenuous work and who lived underthe most unfavourable and insanitary conditions. From thedescriptions of German prisoners of war who escaped fromMurmansk, we know that the Russians had no time orsympathy to waste on prisoners who were affected withscurvy. Anyone who became unable to work was left toperish like a dog, unless a Russian soldier might be compassion-ate enough to put him out of his misery with a blow froman axe or with a bayonet thrust. The six hundred casesComrie describes as having been treated in the hospitals ofMurmansk and Archangelsk were no doubt drawn from amongthe prisoners of war who were lucky enough to be workingin or near these towns. The diet is said to have been fairly

THE ANTISCORBUTIC COMPLETTIN C 249

varied, consisting of flour or biscuit, rice, oats, peas or beans,frozen meat or tinned meat, salted herrings, bacon, salt pork,tea, sugar, salt, and preserved lime juice—the last, we maypresume, only in the towns. Comrie tells us that the rationswere meagre, and that the diet was extremely poor in carbo-hydrates ; and we know from other sources that in actualitythe diet was less varied than on paper, and that the qualityof the nutrients left much to be desired. But even if thesefoodstuffs had been unimpeachable in quality, even if theyhad been supplied according to schedule and in abundance,they would still have induced scurvy, for the diet namedcontains very little C, and the preserved lime juice of commerceis of course quite inactive. In Murmansk, therefore, thelack of C must have been the main cause of scurvy.

Outbreaks of the disease, however, were not confined tothese remote corners where the supply of food satisfactoryboth as to quality and quantity was a difficult matter ; scurvymade itself known in even Western Europe. The British hadexperience of it from time to time when the supply of potatoeswas tending to run short.

Wiltshire J3O3 reports upon an epidemic of scurvy in 1917among the Serbian soldiers on the Salonica front. In thisinstance, the scorbutogenic diet consisted of bread and meat,the latter being mainly tinned meat or frozen meat cookedby boiling. Small quantities of the lime juice of commercedid not prevent the occurrence of scurvy. Wiltshire mentionscases in which scurvy occurred although " an abundance " ofboiled potatoes, onions, and spinach had been eaten; herewe may suppose, either that the boiling had been undulyprolonged, or else that the water of the first boiling had beenthrown away. Special researches made by this investigatorshowed that germinated beans, which were used after a timeboth prophylactically and therapeutically, were far moreeffective than fresh lemon juice. Even severe cases, whichresisted treatment with lemon juice, were speedily cured bygerminated beans. Here, then, manifestly a lack of C inthe diet was the decisive etiological factor.

Chick,I237 who studied the illness among children in Englandand in Vienna, found that the main defect of wartime feedingwas everywhere a poverty in C, to which a lack of A, B, and

250 VITAMINS

inorganic salts, was often superadded. Somewhat earlier,Frank I005 had drawn attention to the frequent occurrence ofinfantile scurvy among artificially fed infants in the VienneseInstitute for Mothers and Nurselings. Chick and Dalyell 1O55.1238, 1278 describing their Viennese experiences, insist uponthe poverty in the children's food in respect of C ; and theysay that the trouble was accentuated by the fact that, onthe one hand, the institutional diet (containing an abundanceof calories) induced rapid growth among the children, and,on the other hand, there were grave errors in the preparationof the food. Thus, in general, the period of boiling wasexcessive ; and, after boiling, the food was usually kept warmfor a long time, whereby the complettin content was yetfurther reduced. Most disastrous of all is the practice commonin South Germany of preparing vegetables by first boilingthem and pouring away the water in which they have beenboiled, and then masking the insipidity of the flavour byadding a sauce made of charred flour and fa t ! When, atthe sun-bath station of the Viennese University Clinic itbecarpe necessary during the winter to restrict for eight weeksthe supply of fresh vegetables, scurvy appeared with positivelyexplosive violence.

I must refer in passing to an exceptional instance XII4 inwhich scurvy appeared in a four-year-old child nourishedalmost exclusively upon soup, coffee, and boiled milk—withthe remark that such cases are, in truth, far less exceptionalthan might be supposed. In Germany, when they are mild,they are usually confounded with rickets; but at least twoinstances of epidemic scurvy in institutions were recorded inthis country during the war. I shall presently have to referto the outbreak of scurvy in the Frederick the Great Orphanageat Rummelsburg near Berlin, described by Erich Miiller.1*68

The other epidemic was reported by H. Vogt,I04* who in 1919had nine cases of infantile scurvy under observation in theAltstadt Hospital in Magdeburg. The terrible rise of pricesin Germany is, at the time of writing, the cause of the frequentoccurrence of scurvy, for many people are living almostexclusively on bread.J555» X556

Finally, during the last years of the war, tHe Swedishnewspapers contained numerous reports of epidemics of scurvy

T H E ANTISCORBUTIC COMPLETTIN C 251

in Northern Sweden. The diet in this area consisted mainlyof very coarse, bad bread, with a small quantity of potatoesand salt bacon, the beverage being a coffee substitute withoutsugar or milk.

3. OCCURRENCE OF THE ANTISCORBUTIC

WATER-SOLUBLE C.

a. Occurrence.

The complettin C is found in special abundance in freshvegetables 751,8<>0,Io66 and fruits.106* The various fruits of thegenus citrus (lemons, limes, oranges, etc.) have long beenrenowned as antiscorbutics. The richness of these fruits inC appears to vary directly with their sweetness. McClendon II29has even maintained that natural nutrients in general arericher in C in proportion to their sweetness. But this asser-tion must be accepted with reserve; and certainly honey,29*the sweetest of all natural products, contains no C. Thelemon in common use, and its juice, though when fresh bothare very active,65, Io66 is less rich in C than the lime,I]C77 whilethe orange and its sweet juice are richest.491, 577, Io66 Theinner layers of orange peel are likewise rich in C, and as asupplement to an otherwise scorbutogenic diet can act as avaluable prophylactic and curative agent even after monthsof drying.751 The juices of other fruits are curative inscurvy 4", 1066 - some of them, like grape juice, are effectiveprophylactics.1066 Apples do not contain much C, but arecurative; cucumbers,1066 tomatoes,838, Io66 and bananas ,^are both prophylactic and curative. According to Weill andMouriquand,756 vegetables and fruits contain more C in pro-portion as they are greener; when they ripen, their richnessdiminishes. In conformity with this statement, we find thatripe hay, according to Hess and Unger,75° contains very littleC, and straw even less.

White cabbage in small quantities as supplement to anotherwise scorbutogenic diet is both prophylactic I71» l86, 577.754, 1053 and curative,65, I 05, 8 o 6 but is less rich in C thanspinach.83J Fresh green cabbage is as rich as oranges in theantiscorbutic complettin.II]C5 I have already mentioned thatdandelion can prevent the onset of s cu rvy l 8 6 ; and other

252 VITAMINS

green leaves, such as the blades of cereals,IT99 and t imothygrass,^1 are rich in the complettin C. Even richer than orangejuice are spinach,83* lucerne, 83X> IO53 and, above all, clover.^1* IO53Onions are said to be very rich in C, and in t he raw state(like potatoes) are reported to be most valuable for the cureof scurvy.IO25» Io66 Even when boiled, potatoes contain enoughC to prevent scurvy.56> 105 Beetroots 9l8 and carrots I05> 9l8

can cure scurvy, and can prevent it I 0 5; and both the alco-holic 391 and the aqueous extract of carrots Io66 possess thispower in a high degree. Among root crops, ripe turnips areespecially rich in complettin C 9l8> 1057—almost as rich asoranges. But the complettin C in turnips seems to be lessaffected by storage and less thermolabile than the samecomplettin in oranges.I3CI5

According to British physicians,1066 fresh meat and rawmeat juice were found extremely effective against scurvy.If this be so, either the amount of C in meat mus t be veryvariable, or else there must have been given in addition toflesh-meat some such organ as the liver (which is especiallyrich in C)—for, according to Dutcher, Pierson, and Biester, I l84muscular tissue contains very little C. But the British doctorsgave, in addition to the meat, not only milk, and oranges,lemons, etc., but also the before-mentioned salad made ofraw potatoes and onions with malt vinegar. W e need not ,therefore, attach much importance to the supposed effectof the meat. On the other hand, we know that polar explorers(Amundsen, for instance, in the South Polar region), thoughtheir diet has consisted mainly of biscuit, chocolate, andmeat dried in the cold, or tinned meat, have been able b ythe occasional consumption of fresh seal meat t o keep thedreaded scurvy at bay. We must either assume, with Dutcher ,that the flesh of sea mammals contains more C than t h a tof land mammals; or else we must suppose t h a t the polarexplorers ate such large amounts of the fresh seal meat t h a tthey obtained enough complettin despite the small proportionof it in muscular tissue.

I t is not surprising that green, unripe beans should befound to be rich in C,9l8 and to be curative in scurvy, for inthis stage of development they must be regarded r a the r asvegetative than as reproductive organs ; but very remarkable

T H E ANTISCORBUTIC COMPLETTIN C 253

indeed is the report of Hess,49* that ripe cotton seeds canprevent scurvy. For we know that w h e a t , ^ barley,749, 885oats,1^, 5*7,577, 749, 750,841, 885 and s o y beans,749, 831 cereals ingeneral/5, 816,693 see^s ^ general,1^, 203 bread,64, 65, 186, ios5

and the brans of the cereals,885,969 are so poor in C that theyhave always proved inadequate. We have learned tha t haycontains too little C. Its poorness in this respect may eitherbe due to storage ; or, more probably, to the ripening process,for Rossi 741 states that dried green grass, as a supplement toan oats diet, can prevent scurvy in guineapigs.

Opinions differ concerning the value of cow's milk as anantiscorbutic. According to Fr6lich,IO7 Hopkins,267 Barnesand Hume, 969 and Willcox,106* fairly small quantities of milksuffice to ward off scurvy; but according to Cohen andMendel,749 Osborne and Mendel,7379, 831, 1131 Chick, Hume, andSkelton,689 and Wollman,89* fresh milk contains but little C,its richness being stated by Chick, Hume, and Skelton to beless than one-hundredth of that of orange juice. Heim 533witnessed the onset of scurvy in adult guineapigs on anexclusive milk diet. Pitz *93 feeding guineapigs on oats, wasnot able to prevent the outbreak of scurvy by supplementingthe oats with a fairly abundant ration of milk*

6. Natural Variations in G Content.

Apart from the varying resistance of the experimentalanimals, the contradictions in the before-mentioned reportsare readily explained by the consideration that the C contentof the different fodders and other nutrients may vary con-siderably at different times. In such substances as hay,which is among the nutrients that stand on the borderlinebetween adequacy and inadequacy, the variations may makethe nutrient inadequate at one time whereas a t another timeit may contain a fairly liberal supply of C. More especiallydoes this consideration apply to milk. The animal organismis just as incompetent to synthetise the antiscorbutic com-plettin as to manufacture the other complettins for itself;it is entirely dependent upon the supply of C in the food.1026. I299According as the food contains more C or less, the animalorganism will possess a larger or a smaller amount of C. I tis true that the mainmary glands have the power in the case

254 VITAMINS

of C that they have in the case of the other three complettinsand in the case of the different proteins and inorganic salts.When C is sparsely supplied in the food, the quantities thatare circulating in the maternal organism are commandeeredfor the milk. But such a process has inexorable limits, andwe have seen that in the case of the growth-complettin B,and still more in that of the fat-soluble growth-complettin,when they are persistently lacking in the diet of a lactatinganimal, the milk, though otherwise normal in composition,may be deficient in these complettins. Manifestly the com-plettins are of such vital importance to the maternalorganism, tha t the commandeering process by the mammaryglands cannot go beyond a certain point. As regards inorganicsalts, the self-sacrifice of the maternal organism may proceedto such a pitch that grave diseases (osteoporosis, for instance)may ensue. In the case of the three main classes of nutrients—proteins, fats, and carbohydrates—the maternal self-abnega-tion may result in severe signs of malnutrition appearing inthe mother at a time when the milk, though certainly restrictedin quantity, still contains the normal proportions of the threemain nutrients. But as regards the complettins, matters donot go so far as this. When studying beriberi we learnedthat sucklings may become affected with beriberi at a t i n ewhen the mother still appears healthy, for her milk isdeficient in vitamin. The secretion of milk containing nogrowth-complettin would be an absurdity, and when thesupply of this complettin runs short, the quantity of thesecretion is reduced; but the proportion of A in the milkmay fall off to such an extent that growth is inadequate andthe offspring become rachitic or are affected with xerophthal-mia. I t would seem that the C content of the milk can beeven more readily reduced. To express the matter in anotherway, C is so important to the life of the mother, and conse-quently to the life of the offspring, that the maternal needhas the first claim. That is why according to Ingier 387,405when gravid guineapigs are fed on a diet deficient in C, thefoetuses become affected within ten to twelve days with typicalinfantile scurvy. When the gravid guineapigs have beenproperly fed until near the time of delivery, a suddeti transitionto a scorbutogenic diet does not affect the foetuses, which

T H E ANTISCORBUTIC COMPLETTIN C 255

are normal at b i r th ; but the milk is inadequate, and theoffspring speedily become affected with scurvy. Pregnantanimals put upon a scorbutogenic diet fall ill with scurvymore rapidly than non-gravid animals, and frequently dieof the disease before delivery.

These considerations explain the facts observed byFigueiraIO46 and by Dalyell and Still,IO55 who noted thatinfants at the breast may become affected with scurvy althoughthe mother appears perfectly healthy.

As regards the C content of cow's milk in particular,Barnes and Hume 9*9 were the first to point out that the varia-tions in the complettin content are subject to seasonal changes.The C content is highest from May to July, and lowest duringthe winter months. Hart , Steenbock, and EHis,x*33 Hess,IO55and Dutcher and his collaborators, m* likewise refer to thisdependence of the richness of milk in C upon the seasons,and they regard the varying amount of C in the fodder asthe essential cause of these changes. In spring and summer,when plants are in the most vigorous phase of their develop-ment, they contain comparatively large quantities of C ; onthe other hand, the ripening of hay is attended by a gradualdecline in the amount of C it contains, which may be reducedto an inadequate proportion.

I t is owing to this scanty supply of C in the milk thatbottle-fed infants sometimes become affected with scurvy.Of course the customary practice of diluting cow's milk forthe hand-feeding of infants lowers the percentage of C in thefood to a dangerous extent, seeing that the C content of cow'smilk is already low in many cases.737

Eggs contrast with milk as the first nutrient of a growingorganism, in that they appear to contain very little C,83*and certainly cannot cure scurvy.75<> In this poverty, theyresemble seeds.

Fresh yeast S&, 737 is far more active than mi lk ; but theautolysis of yeast destroys the complettin C,49* though ithas no effect upon vitamin and the growth-complettin.

c. Effect of Germination upon the C Content of Seeds,We have already learned that seeds, which in the quiescent

state contain so little C that they have no antiscorbutic

256 VITAMINS

influence, develop large quantities of this complettin duringgermination. Consequently, an exclusive diet of germinatedseeds is not scorbutogenic; and a supplement of germinatedseeds to a scorbutogenic diet has prophylactic and curativeeffects.102* l87> 203, 267, 735, 749, 841, 918, 972, 1057, 1066, 1118 i n con-formity with this we find that malt extracts, and especiallythe fresh watery extract of green malt, have antiscorbuticqualities.533 The antiscorbutic substance in germinated seedsis not in the cotyledons, and still less in the primary rootlets ;it is mainly found in the leaves, and the process of germinationper se does not increase the C content of the seed. The anti-scorbutic powers of germinated seeds is not fully developeduntil after the lapse of three days or more, when the formationof the first leaves has begun.734 For this reason, the actualgerm is inadequate in respect of C content, 491 whereas theleaves of the germinated seed are more effective than theentire germinated plant. If we wish to use the aggregategerminated seeds as a prophylactic nutrient, i t is best to waituntil the leaves have grown to a length of from half to three-quarters of an inch.^1 When germinated seeds have beendried, they no longer contain the antiscorbutic complettin. 93, ifi7

4. PROPERTIES OF THE COMPLETTIN C.

I t follows from the foregoing that the complettin C mustbe soluble in water. According to Hess and Unger,75r andaccording to Harden and Zilva,794 it is soluble in alcohol tha tis not too strong, and is therefore retained in the alcoholicsolution when the fruit acids are precipitated from fruit juicesby means of calcium carbonate and alcohol. Like the com-plettins previously considered, C has a fairly high power ofresisting even strong mineral acids,536 and a moderately acidreaction of the medium definitely favours the durability ofthe complettin 756; but C is rather sensitive to alkalies. 53However, as in the case of the growth-complettin B , t h edestructive effect of alkali is not immediately manifest, andcomplete destruction is not achieved for a considerable time.899The complettin C is not entangled in precipitates and carrieddown with them; and it cannot be removed from orangejuice, for instance, by alumina or by a Chamberland filter.688

In the preparation of Osborne and Mendel's protein-free milk,

THE ANTISCORBUTIC COMPLETTIN C 257

C is retained by the milk, which does not lose any of its anti-scorbutic power.737 Like the fat-soluble cornplettin A, thewater-soluble complettin C is sensitive to oxidising agents. 1O55TMs doubtless is the main reason why the storage of driednutrients originally rich in C leads, even when the dryingprocess has been carried out with the utmost care, to a ratherrapid disappearance of the C content. From a further studyof this matter we learn that dried vegetables suffer less fromstorage as regards their C content in proportion to the drynessof the air;

I3»4 so that the storage is best effected in the presenceof phosphorus pentoxide. I t is remarkable tha t Hoist andFrolich :3°4 have failed to draw the obvious conclusion asregards the mechanism of this reaction, which has an importantbearing on our knowledge of the complettin : in the presenceof air, the dried green vegetable substance has a catalyticaction upon the aqueous vapour the air contains, leading tot i e formation of hydrogen peroxide, and this latter, whichexerts an oxidising influence upon the complettin, destroysits characteristic antiscorbutic quality.

Reports vary concerning the thermostability of the anti-scorbutic complettin. Hoist and Frolich inform us that theboiling of cabbage, carrots, dandelion, and potatoes, reducestheir prophylactic power l 8*; and according to the sameauthorities 305 and also according to Plirnmer,I]c59 expressedcabbage juice is rendered inactive by boiling. Frolich I07, 204found that raw milk in small doses did not prevent guineapigsfrom becoming affected with scurvy, but was able to curethe disease ; this curative influence is greatly reduced whenthe milk has been heated to 980 C , and completely disappearsafter ten minutes' boiling a t 100 ° C. I think, however, thatthe last statement must be an exaggeration, for the experi-ments of Nobel *3*6 have shown that, even after one hour'sboiling, milk contains considerable amounts of C, so that adouble or treble quantity will cure infantile scurvy. Accordingto Barnes and H u m e , ^ milk still retains after boiling thepower of protecting children against scurvy, provided onlythat the boiling has not been long continued and that afterboiling the milk has been rapidly cooled.

According to Delf,8°6 the antiscorbutic power of whitecabbage is injured by heating; and she tells us IIJ5 that the

258 VITAMINS

juice of green cabbage has its efficacy as an antiscorbuticnotably reduced by twenty minutes' boiling, while by anhour's boiling about five-sixths of the antiscorbutic complettinare destroyed. In turnips, the C is more resistant toboiling,IXI5 which seems easy to explain by the considerationthat the heat cannot so readily make its way into the interiorof the masses. The antiscorbutic qualities of germinatingseeds are largely destroyed by boiling.9l8 Exposure for fromone to three hours to a temperature of 1200 C. destroys theantiscorbutic faculty of all nutrients. There is general agree-ment that prolonged heating at a moderate temperature isfar more noxious than brief exposure to a high temperature.1066

This makes it obvious why the pasteurisation of milkgreatly reduces the C content of this nutrient^1 1 and whyinfants and children fed on pasteurised milk are so apt tosuffer from scurvy.800* m 2 Of course in the process of condensa-tion, the antiscorbutic qualities of milk are gravely impaired.901

In young monkeys, a diet of condensed milk induces infantilescurvy *", *49; and in adult monkeys,211 and also in guinea-pigs 885 it induces typical scurvy. Since the complettin C issensitive to alkalies, we can readily understand tha t it iscompletely destroyed when milk is sterilised after the additionof sodium citrate, which has an alkaline reaction. I389 Gener-ally speaking, the sterilisation of nutrients impairs theirantiscorbutic power, being more injurious in proportion tothe height of the temperature. 741, i°*5 Tinned meat andtinned milk are therefore invariably scorbntogenic "94; butvegetables with an acid reaction may still retain considerableantiscorbutic powers after cautious sterilisation.899> "94

Since prolonged heating is in any case injurious, it isobvious that the drying of nutrients at a raised temperaturemust be extremely disadvantageous. Hoist and Frolich1 8 6

report that the drying of cabbage, carrots, and dandeliongreatly impairs their antiscorbutic qualities ; such efficacy asis retained by dried cabbage 749 is still preserved after briefheating at ioo° C , but is completely destroyed at n o ° C.*5

Dried potatoes are likewise inadequate.65 Givens andMcClugage "48 have made a thorough study of the efiect ofdrying potatoes. They found that finely minced raw potatoescould be boiled for fifteen minutes without ill-effect, b u t that

T H E ANTISCORBUTIC COMPLETTIN C 259

their antiscorbutic efficacy was considerably impaired byone hour's boiling. The boiling is bet ter borne when thewater contains 0-5 % of citric acid. Potatoes dried in vacuoat a temperature ranging from 45 ° to 60 ° C. lost much of theirefficacy ; and the greater par t of the complettin was destroyedby drying in an air current for from six to eight hours at atemperature ranging from 350 to 400 C . ; subsequent briefboiling reduced the complettin content still further. Equallybad was the effect of drying for from four to six hours in anair current a t a temperature ranging from 55° to 6o° C . ;drying for from two to three hours a t a temperature rangingfrom 750 to 8o° C. destroyed almost all the complettin C.Preliminary t reatment of the potatoes with 2 % acetic acid or0-2 % hydrochloric acid for from eighteen to twenty hoursbefore drying, had no influence. Four minutes ' steaming ofthe minced potatoes before drying a t a temperature rangingfrom 550 to 6o° C. destroyed most of the complettin, and asubsequent brief boiling destroyed what was left. Potatoesbaked in their skins for from forty-five to fifty-five minutes a ta temperature of 2040 C , then skinned, and dried at a tempera-ture ranging from 450 to 50°C, could still prevent scurvy;the skins of the baked potatoes no longer contained anycomplettin. These authorities infer t ha t the destructiveeffect of the drying must be part ly due to the influence of aferment, seeing tha t less C is destroyed in proportion as theheating process is a rapid one. Here it is impossible to followthem, for were their reasoning correct, the preliminary treat-ment with steam should have given the best results, whereasthis proved extremely destructive to the antiscorbutic powersof the potatoes. Though it was found tha t baked potatoeswere still comparatively efficient as an antiscorbutic, wemust not assume tha t this was because the heat was greater,and tha t the alleged ferment was thereby more rapidlydestroyed, for the substance of potatoes has a low conductivityto heat, and within the time allowed for the baking thetemperature in the interior of the tubers cannot have risen veryhigh. Still, there may be something in Givens and McClugage'stheory after all, for Delf and Skelton 8o7 s ta te t h a t cabbage doesnot forfeit i ts antiscorbutic virtues so completely on dryingwhen, as a preliminary, i t hats been dipped in boiling water.

260 VITAMINS

According to Givens and Cohen,754 in cabbage and potatoesC bears a quick but careful drying so well that the driedproduct is still effective as an antiscorbutic; but prolongeddrying, especially at a considerable heat, completely destroysthe complettin. From tomatoes, according to Givens andMcClugage,838 a dried product that is still effectively anti-scorbutic can be prepared.

Owing to the acidity of lemon juice, the C in this juicewill bear an hour's heating at ioo° C.I05; and in the case oforange juice II09 and lime juice,XI77 cautious evaporation tothe consistency of a syrup does not impair the activity. Basset-Smith I249 was able to prepare a very active dried productby boiling fresh lemon juice for five minutes, cooling, andcondensing in vacuo at an ordinary temperature to a specificweight of i • 3 ; he thus secured a strongly acid viscous fluidwhich could be made into tablets with lactose, or some similarvehicle. Hawk, Fishback, and Bergeim IO58 were able tosecure an active dried product from orange juice by evaporatingit to dryness in vacuo at an ordinary temperature. Accordingto Harden and Zilva,794, etc. the precipitation of the fruitacids with calcium carbonate and alcohol does not impairthe antiscorbutic efficacy of lemon juice, but the juice nowrendered neutral is injured by subsequent preservation forfourteen days at an ordinary temperature, and is injured stillmore by evaporation in vacuo at a temperature ranging from300 to 400 C. The untreated juice bears such concentrationvery well, and so does the juice after precipitation of t heacids if it be at once weakly acidulated with citric acid.

Delf,JII5 who has made an exhaustive study of this ques-tion, finds that orange juice in its natural state of aciditycan well bear heating for an hour a t a temperature rangingfrom 700 to ioo° C , and that even after the juice has beenheated for an hour at 1300 C. it is merely necessary to doublethe prophylactic dose. In orange juice the thermostabilityof the complettin is therefore twice as great as in expressedturnip juice. But even when the acidity of the orange juicehas been reduced to correspond with the low acidity of t h eexpressed turnip juice, the thermostability of the C in t h eformer is still retained, and it is therefore not due to t hestrongly acid reaction of the juice. Orange juice t h a t had

T H E ANTISCORBUTIC COMPLETTIN C 261

been heated in sealed tins for from twenty to thir ty minutesat a temperature ranging from 8o° to ioo° C. was found tobe still fully effective as an antiscorbutic after five months.

Nevertheless, i t seems undesirable to trust to the anti-scorbutic efficacy of stored products. The antiscorbuticpower of expressed cabbage juice,I05 lemon juice,794, *>66 andorange juicers1 seems to disappear in consequence of prolongedstorage. Perhaps the cause of this degradation is not somuch a primary instability of the complettin as its sensitive-ness to the oxidising influence of the atmosphere. This, wemay presume, explains Delf and Skelton's observation,8o7that the storage of dried cabbage for from two to three weeksreduced its C content by about nine-tenths, and that threemonths' storage ^completely destroyed its antiscorbuticefficacy.

The complettin seems to be peculiarly unstable in germin-ated seeds. I have more than once mentioned tha t in theseC is destroyed by brief boiling. Drying also destroys it com-pletely. I02» Il66> J345 The soaking of other dried vegetablesappears to be very injurious to the C they contain.I]C99

Barnes and Hume state tha t the drying of milk reducesits antiscorbutic efficacy to about two-fifths of the original.But the extent to which this reduction takes place varieswith the method of desiccation, for Hess and Unger &99 reportthat milk transformed into an absolutely dry powder withina few seconds a t a temperature of 1160 C. by the Just-Hatmakerprocess was still fully efficient. In Germany, similar resultshave been secured by the use of the Zetror apparatus of theBenno-Schilde Company. Especially valuable, from thispoint of view, is the Krause method of producing dried milk,which from the descriptions would seem to be identical withthe American.

According to Hess and Unger^s1 the most actively anti-scorbutic vegetables lose their efficacy on drying. ErichMiiller *°o refers the outbreak of scurvy in the Rummelsburgorphanage to the use of milk tha t had been twice pasteurisedand to the use of the dried vegetables of commerce. Thelatter were especially deleterious thanks to their having beenbleached before drying, and having thus lost their excess ofbases. A cure ensued upon the giving of milk tha t had only

262 VITAMINS

been once pasteurised, together with fresh vegetables. [I doubtif it can have made much difference whether the milk had beenonce pasteurised or twice, seeing that a single pasteurisationsuffices to destroy the C of milk, which in any case containsrather a small quantity of this complettin.]

Manifestly the German practice of bleaching vegetablesbefore preserving them, and especially before putt ing themon the market in a dried state, is extremely undesirable.Not merely do the vegetables forfeit their excess of bases ;but since the complettins C and B and the antineuritic Dare all readily soluble in water, they are dissolved out in thefirst boiling.8^* 1087, 1278

5. COMPOSITION OF THE ANTISCORBUTIC

COMPLETTIN C.

A chemist may be forgiven for inability to refrain fromacting after his kind, and for the involuntary a t tempt todraw, from the available data, conclusions as to the compositioneven of substances that have not yet been isolated ! Thebehaviour of the complettin C is so characteristic tha t wecan, in fact, with some degree of certitude predict at leastone peculiarity of its composition. First of all, this complettinis thermolabUe. We know of a large number of chemicalchanges which ensue when the substances are warmed. Letme mention a few of them. Ketones and aldehydes canundergo transformation into the corresponding enol forms.Alcohols containing several hydroxyl groups in a t least ay relationship to one another, or oxi-acids in which hydroxyland carboxyl are separated from one another in like mannerby at least two carbon atoms, and similar amino-acids, canbe transformed into anhydrides with the splitting off of wateror ammonia, and cyclopoeisis. Unsaturated compounds,especially such as contain two conjugated duplex compounds(separated by a simple link), will, on being wanned, veryreadily combine with a molecule of water, in conjunction withthe formation of simple unsaturated compounds. And so on.

The extraordinary sensitiveness of the substance tooxidation has been repeatedly referred to. The complettinbecomes inactive when a fluid containing it is stored, andstill more when a dried nutrient containing it is stored, with

T H E ANTISCORBUTIC COMPLETTIN C 263

free access of moisture and a i r ; it is also rendered inactiveby direct oxidation, as for example by the action of hydrogenperoxide. This fact, too, justifies certain conclusions as toits composition. One possibility is t ha t i t contains readilyoxidisable molecular groupings like those of the ketones orthe aldehydes. Another possibility is t h a t of duplex combina-tions, which are sometimes readily oxidisable. Especiallysensitive in this respect are, once more, the conjugated duplexcompounds, which undergo transformation into dioxy-compounds under the influence of mere traces of hydrogen per-oxide, thus : R . CH : CH . CH : CH . R ' + HO . OH ==

R . C H 2 . CH(OH) : CH(OH) . C H 2 . R ' .I t is characteristic of such conjugated compounds tha t

when stored for a long time in the presence of moisture andair, and rapidly when the temperature is fairly high, theytake to themselves traces of hydrogen peroxide formed inthe aqueous vapour, and thus by degrees are transformedinto an entirely new substance. The process is favouredwhen the body under consideration can itself play the par tof a catalase (as so often happens with the terpene deriva-tives), or when other oxygen conveyers are found in themixture. This state of affairs obtains in plants, and in themajority of fresh animal tissues ; in both cases there is presentmore or less cata lase; furthermore, animal tissues containhaemoglobin, and vegetable tissues contain chlorophyll, bothof which are oxygen conveyers.

We have already seen tha t by rapid heating at a hightemperature and subsequent drying at a low temperature,the keeping qualities of the product are favourably affected ;and we have drawn the conclusion tha t an enzyme mayperhaps contribute to the decomposition of the complettinin the dried preparation. We have learned tha t prolongedheating a t a comparatively low temperature ranging from300 to 400 C. is more injurious to the integrity of C than boilingi t for as long as an hour. We know, moreover, tha t the sub-stance is extremely sensitive to the action of the oxygen ofthe air, b u t t h a t this sensitiveness is much less marked whenthe air is perfectly dry.I3°4 From all these considerations weare inclined to draw the conclusion that the complettin 0 isprobably a conjugated duplex compound. Furthermore, the

264 VITAMINS

idea is supported by the fact that the substance is renderedinactive by temperatures over n o 0 C , for at high temperaturesmany dien compounds are converted into monin compounds.( - C H = C H - C H = C H 2 - becomes - CH2 - C = C —CH2 - - ) . The behaviour of the substance when exposed toultraviolet light confirms the idea. When ultraviolet lightacts on damp air-containing substances, hydrogen peroxideis formed, and this is fairly stable in weakly acid solutions,whereas it is extremely unstable in alkaline solutions. Zilva 9^tells us that ultraviolet light in weakly acid or in neutralsolutions has very little influence upon the antiscorbuticcomplettin, bu t speedily renders the complettin inactivewhen the solution is weakly alkaline.

Of course these hypotheses do not exclude the possibilitytha t the substance may also contain other unsaturated groupswhich may lose their activity in some other fashion throughthe operation of heat.

Beyond this, we have nothing positive to say regardingthe nature of the antiscorbutic complettin. Delf8o6 hassuggested that we may have to do with a special enzyme,seeing that it is sensitive to temperatures which denature theproteins. But outside the living body, it is just as sensitiveto the much lesser heat which is the optimal temperature forwarm-blooded animals, and we are therefore led to infer tha tthe process whereby it is rendered inactive when heated mustbe of a different nature. Fiirst l87, 203 declared a good manyyears ago that this complettin could not be indentical withany of the familiar forms of proteins, fats, carbohydrates,salts, or enzymes.

Funk2O5 seems to have been inclined at the outset tobelieve that C was identical with his vitamin, and Freise 391

regarded it as at least akin to the vitamins. This theory wasto some extent supported by the frequency with which beriberiis complicated with scurvy,Il65 and also by the fact t ha t inpreparing the vitamins small quantities of C are precipitatedwith these. Subsequent investigation has, however, shownbeyond a doubt tha t we have no justification for assumingthe identity of the two classes of complettins, for they differextensively in respect both of chemical properties and ofphysiological effects.

T H E ANTISCORBUTIC COMPLETTIN C 265

The non-identity of C with the fat-soluble complettin Ahas been established by a large number of investigations.491* 75°»751. 754, 805, 831, 1194 So has its non-identity with B.491* IIl6»1153, 1194

At this juncture, therefore, we can say nothing definiteas to the nature of the antiscorbutic complettin.

6. T H E PHYSIOLOGICAL CONSEQUENCES OF

C DEFICIENCY.

a. Clinical Picture.

Thus when there is a lack of C in the diet, a characteristicillness arises, the disease known as scurvy. In minor cases,those running a subacute or chronic course, scurvy is oftenconfounded with other disorders; for example, many slightcases of infantile scurvy are mistaken for rickets. Thesymptoms of the initial stage are anaemic and cachecticmanifestations, such as loss of weight, fatigue, drowsiness,disinclination and incapacity for work, mental depression,peevishness, etc. The emaciation makes rapid progress, andat the same time the skin becomes pale, flaccid, and remarkablydry. There are pains in the joints, especially in those of thelower extremities. In this stage the disease may remainarrested for a considerable period; and since in childrenduring the phase of growth there occur in scurvy disturbancesin the normal process of bone formation, it is not surprisingthat the illness should be confounded with incipient rickets.But even in this early stage there are pathognomonic symp-toms in the form of haemorrhagic manifestations, which insubacute and chronic cases of scurvy strongly resemble thoseof purpura.

In typical attacks, after about a fortnight the signs ofthe haemorrhagic diathesis become conspicuous, there beingin most cases a characteristic affection of the gums. Thesebecome bluish at the edges, and are greatly swollen, so as toproject around and between the teeth. The tumefied gumsare extremely sensitive, bleed at the slightest touch, andsoon begin to ulcerate. As the swelling increases, the gumsbecome necrotic, and assume a whitish or a brownish-blacktint here and there, the ulcers being coated with evil-smelling

266 VITAMINS

greyish-white masses. The teeth are loosened and decayed;mastication is impossible; the breath is horribly foetid.Whereas in purpura, the haemorrhages begin in the; subcuta-neous tissue, and only extends by degrees to the gums andthe rest of the buccal mucous membrane, in scurvy they areconcentrated around the teeth and around neglected r<x>ts,so tha t the observer has the impression tha t the tremble startsfrom the teeth. Apart from the affection of the gums, thesigns in the mouth are merely those of slight stomatitis withmoderate swelling and a little bleeding. In severe cases thereensue, to the accompaniment of moderate febrile manifesta-tions, other haemorrhagic symptoms, such as purpuric patcheson the skin, intermixed with lichenoid or herpetiform eruptions,large ecchymoses, and also non-haemorrhagic hullac. Incontradistinction t o purpura, the eruptions in scurvy have astrong tendency towards ulceration, the ulcers being largeand sluggish ; sometimes they are very deep, and when theyare situated in the flexures of the joints they are apt to leadto contractures should the patient recover and cicatrisationoccur. Haemorrhages may occur in various other pa r t s ;when they are superficial, they are prone to suppurate, areextremely painful, and are often attended with considerableirregular pyrexia. Should there be any prrexistent scars inthe bones (the seats of old fractures) these are apt to ?often.In many cases, the articular ends of the honun and thecartilages of the joints become diseased and the synovialmembranes grow dry, and these changes may lead to permanentstiffness of the joints. The bone affections may even resultin the complete separation of epiphyses. Sometimes, gener-ally an an early symptom, there may be severe haemorrhagesfrom the mucous membranes like those that occur in haemo-philia ; among these, epistaxis is the most common.

b. Pathological Anatomy,

The haemorrhagic symptoms are not difficult to explainon the supposition of a change in the walls of the capillaries,perhaps accompanied (as in haemophilia) by a disturbance ofthe process of coagulation of the blood. On the other hand,there is as yet no explanation of the characteristic affectionsof the bones, which enable us after the lapse of thousands of

T H E ANTISCORBUTIC COMPLETTIN C 267

years to ascertain from an examination of the skeleton thatthe person to whom i t belonged had died of scurvy, or elsehad recovered from a severe attack of the disease. There areno other organic changes of a specific nature. The atrophyof the glands and the general emaciation, do not differ in anyway from what we see in other grave disorders of nutr i t ion;and we may assume t h a t they arise because a scorbutogenicdiet is usually poor in B as well as in C, so that they are notin any way peculiar t o C deficiency. Furthermore, thoughoedema is common in scurvy, it is common in all the deficiencydiseases, and is therefore nowise characteristic of a lack ofthe antiscorbutic complettin.

Owing to the a t rophy of the glands, there is an arrest ofthe digestive secretions. In severe cases, there is completeachylia, and the sal ivary secretion is greatly diminished,having usually a s t rongly acid reaction.6^ These secretorydisturbances natural ly favour the onset of gastro-intestinaldisorders as complications. On the other hand, everythingwhich makes a special claim on the bodily activities, predis-poses to the disease, a n d this statement especially applies tointestinal disorders,1066 a deficiency of the food in calories,febrile disorders,100? a n d vigorous growth.Io87> "78 As in thecase of the other deficiency diseases, the adrenals are excep-tions to the general r u l e of glandular atrophy, for they undergohypertrophy, while a lso exhibiting a partial fatty degeneration,especially of the cort ical layers.n77, ™>*

Except for the reduction in the number of erythrocyteswhich is characteristic of the haemorrhagic diathesis and especi-ally of its haemophiliac forms, changes in the blood are notconspicuous. There i s , indeed, almost invariably a declinein haemoglobin richness,I242 such as is usual in anaemic states ;and there is an increase in the urea.577 Although the resistanceof the organism to infections is so greatly reduced, the Cdeficiency does not l ead to any changes in the serologicalconstants of the blood. 9*7, » »

As regards metabolism, the nitrogenous balance is usuallynegative, and, in a c u t e cases at least, there is retention ofphosphorus and calcium—but these manifestations are notespecially characterist ic of C deficiency. All the patients,a t any rate in the early stages, and as long as the mental

268 VITAMINS

debility has not become excessive, exhibit a vigorous cravingfor fresh nutrients, whether meat, milk, fruit, or vegetables.I009McClendon XI29 is certainly right when he insists that in astate of nature this craving must be one of great survivalvalue for men and animals. Among the American soldiers inthe trenches, when their rations were restricted to chocolate,eggs, dried milk, and sugar, worked up into a sort of biscuit,he noted tha t this craving became overpowering within twoor three days, and led them to refuse their rations.

The need for the antiscorbutic complettin varies greatlyin different species of animals. Prairie dogs X3o° and rats havea very low requirement, and can live for long periods on adiet containing no C ; on the other hand, some of the otherrodents (rabbits and guineapigs, for instance) are extremelysensitive to a lack of C in the diet. Characteristic in thisrespect is the fact recorded by Harden and Zilva II05 that fora guineapig weighing a few hundred grammes the sameprophylactic dose of C is requisite as for a monkey weighingtwo or three kilogrammes. Furthermore it would seem thatyoung animals of the same species vary in their requirements,and this has led some authorities to formulate the hypothesisthat at birth animals must bring with them from their mothervarying stores of C, the difference between one litter and anotherdepending upon the supply of C to the mother during pregnancy.

c. Reciprocal Relationships between G and inorganicSubstances,

Our account of this matter would be incomplete unlesswe drew attention to the fact that the full ef&cacy of C cannotbe developed unless the diet contains inorganic salts in suit-able proportions. Hoist and Frolich 65 state tha t calcium saltsare useless in scurvy unless C be also supplied, but that a lackof calcium interferes with the rapid and effective action of C.

There can be no doubt that the onset of scurvy is facilitatedby the circumstance that most of the nutrients which proveto be scorbutogenic are deficient in inorganic bases as wellas in C. When Fiirst102 says that nutrients whose ash isalkaline can also give rise to scurvy, an error underlies thisassumption that the inorganic bases are of no value in nutri-tion. All the ash analyses quoted by Fiirst are fallacious,

T H E ANTISCORBUTIC COMPLETTIN C 269

for recent investigations have shown that the nutrients (peas,lentils, and almonds) to which he refers, contain an excess ofacids, this excess being especially marked in the pulses. Onthe other hand, we have a report from Funk 5*7 to the effectthat in certain cases of scurvy the administration of sodiumbicarbonate has proved useful. Some of the features of thepathological anatomy of this disease, especially the bonedisorders and the oedema, indicate that acidosis must playa part in its production.

Florence IX56 has published a speculative paper in whichhe contends that a lack of sulphur may perhaps play a partin the causation of scurvy and infantile scurvy. Althoughthis writer has not done any experimental work in order tocorroborate his theory, there may be some truth in it, formany of the scorbutogenic nutrients, and the cereals inespecial, contain inadequate quantities of cystein; others,such as meat, part with some of their sulphur when stronglyheated, and thus become inadequate in this respect. Perhapssuch a lack may in par t explain the malnutrition.

d. Forms of Purpura in relation to C Deficiency.

The various forms of purpura, and especially purpurasimplex, are to-day regarded by physiologists as the outcomeof chronic malnutrition due to C deficiency. This theory isconfirmed by the fact tha t the most successful treatment ofpurpura simplex is dietetic. Although serum, gelatine, andcalcium salts, are sometimes given by injection in the hopeof increasing the coagulability of the blood, the value ofthese remedies is much disputed. As regards diet, lemonsand other raw fruits, salads, and green vegetables, are foundto be the most useful nutrients. In purpura simplex a curecan be effected by these means without confining the patientto bed, but absolute rest in bed is essential in the graver formsof purpura haemorrhagica if extensive extravasations are tobe avoided.

6. MODE OF ACTION OF THE ANTISCORBUTIC

COMPLETTIN.

No definite opinion can as yet be uttered regarding themode of action of C in the animal organism. In scurvy, as

VITAMINS

in most of the* tlvfu ivw v d i ^ a »i •, tin ie u pmhahly a complexof cansts at work ; f*»r in fann% the peruhar " liability ** ofthe* tissues upon which tin* liability to haemouhages dependsis probably favoured by aridusix But tht* Litter rannot bethe main cause of tin* disease, fur, as \v«« have repeatedly hadoccasion to note, scurvy may aiis<; whm the diet is rich inbases.

The bone diseast'S char.tt t^ri^tic of scurvy bear a certainrcsemblancr to those* which ocnar as a M«<|U«'I (4 A cli'ficiency.The similarity is, howcvtT, vrry Mijififirj.il; and the twocomplettins, A and (', arc shasply ciistiiij^tu lj«'d onr fiom theother, <tsj>«»cially by their behaviour tnwanls alkalies, Wemight rather be inclined to look upon ;u irlo^is as the cause ofthe bone disorders, but we have sren that a* idmis cannot beregarded as the main f.u fur (4 ?.Mirvv.

The negative nitro^enou-* lu l ame , tlie ulcers, etc., mightbe ascribed to a deficiency of the $;r*»wfb mmplr t t in B. butwe have already learned that tins (urnplettin is not alwayslacking in scorbutofjenic diet^.

We have, then, in do with a thara* tefisttr Nvnrimmedependent upon a d*fi< ieucy ui an unknown substance* orclans ui sutManees to wlm h we givr ih«* nainr of the tomjtiettinC, But it remains dubioir* whrthrr .ill the phrnorn<na ofscurvy can as yet be comprised under a unified uutluok.

CHAPTER EIGHT

MALNUTRITIONAL OEDEMA

i . CLINICAL PICTURE.

I N the accounts of the deficiency diseases previously considered,oedema has frequently been noted as a complication, and wehave seen that in certain circumstances it may attain suchproportions as to dominate the clinical picture. This happens,for instance, in the case of wet beriberi. I have, however,been careful to point out that the oedema was no more thanaccessory, and was not an essential feature of the disease.There are, however, many facts to indicate that oedema mayoccur from defective nutrition as a primary disorder. InFrance, and still more in Central Europe, during the warmalnutritional oedema came to be recognised as one of theconsequences of wartime feeding, and has now to be describedas an independent clinical entity. We shall find that experi-ence gained in the study of the other acomplettinoses will beof considerable value in this connexion; and, on the otherhand, tha t an accurate study of malnutritional oedema willthrow light on the etiology of the other acomplettinoses.

Apart from local oedema, due to local causes or to suchnervous disorders as hysteria, it has been customary to recog-nise three varieties of oedema, dropsy, or anasarca, whichoften pass into one another, though in isolated cases they mayappear to constitute distinct types. First of all there is renaloedema, due to the blocking of the uriniferous tubules inconsequence of Regenerative changes in the kidney tissues,or in exceptional cases to grosser mechanical obstructionssuch as those caused by renal calculi. Secondly we have thepassive oedema that arises from an insufficiency of the arterialwalls, perhaps from organic changes in these (hyaline

27X

2J2 VITAMINS

degradat ion) , 01 i t mav h<* ran «*d by ,in abnormal fall inblood pi***1 in«\ ^nn iHmj i ' , pav i w cit'(it*2ii,i m.tv hr due to

a mrc hanit a! ii^l.ix.ttinii «*f thr wal l* uf fh<* bluodvcnsHk,

t'spu ial!v %!*< n th» v AH* not ,whiti«nth ani« tl bv the* sunmuui-

inj; mu « 1 * \ .is happen «to th<> * \\hr> it ni stand f«'Z **XM wvcly

IMI I^ pnnrt i t wh in at uu i k in fa* ton* *, *hopi, 01 oifires.

Wiu'iJ pa» iv*< cMiir* l inn ha . 1 I 4 M ! a Inji^ tun*', it may react

upon th*- h«att, whi< h lias m**ir wuik thtn*t upon it in the

at tunpt to d i i v r th«^ M««w! thi«»u^h tin* n l a v i i ami dilated

vrssrls. "I Jiu•* wr f»rt a ttdtvitt*>n tti thr thud f«<nn, which is

known a* <«u duit c*i d^ina In iatdi.tr nn j i i na , I li** hi*art

has failed, it may b«* i^r flu- I*M «*n just intnt ioni 'd, it may

bt* fr<itit uibr^in wi*akn* * or hum t o n ^ i n t a ! *>r a«({uutti

u <!i*Jifrts, «>i it may bt* a a CMiupluatiust r»r *i*jiii#l (if

i l l in * »«*s, tuxatinti i , «tt H U V % I \ I I tttittiiMtt'd, rat due

oi*dt*ma IH thr out<uni»* <4 a f.ulntr *?f * si* i l lation.

Owing to th«* .nti '*t of th** !4ood t i ram tn p i MVr tirdrma

or taidiac* tjnirnia* afifl ttwin,; tu thr jti«.u in* r«MM* in th«

rontrnt t»f th«* bli««lvt- «1. in »<nd «<M|ima. t l i r

UMlh a i f f i i , an<l th«-v allow a.* tutu tu Iran >id»# into fh<*

in^ t l a n . Jhi* i Ktia%a4atid Jiiud at * timtiJ it* - f

in thr * omp' t fa tm )v m'it Mil<«Mtan«uti% t i *u« , u h u h may

br tltti • tu<>ll«u l»%mnd i n i f n i t n » n , hut sn patt it intiltr»itrs

th«* t l **II*M of thf" «ah» ? oitjan I n a d ^ a n n d * 4 *•% it .t

lat«*-» a! <> 111 tin- vaiioti bod\ <a\iti« ^ lh ' - pant *, tti<€ p

tmUMl t,i\tl\\ thf- pinned *aut i« , th*" put 'ardsal cavity,

AH tin- van* ti« * of ti« d« ina «» h.ivi** on $d* i* d in

wi th th*¥ drhu* m x di «»i * , b« loi i f to th r tU ** r»{ thr

<M*di*tn»tH. In «'XM-p!t<iftaI in tan<ri untv, ;i\ in M-

c4 b i l l i o n 14 v i i r w , thr p,r JVr iw*t}r?ii;i ftj.iV

Mtddhfitlv p*t *» fv«r into c.udui Mt iNna, this h»in^ A ^ign

th»tt thr I H M I I }hv* b t n ^ i i r $*xh,ttr'tt'«i. I hi* apj^ai^nrt* of

cnuhar cit*df in»i an thr fulmtfui t t fotm t»{ lur i t

juHttfir • *i Vi*ry iff. ivr pto^ti'Ar*, {f#r f i r . i th I I M V «rc«r

numicnf fr«m hratt {.ulurr Hut nsalmiirttiunal wdrina,known in (#inn»itiv ,%% M Hutiifcr^idriti *' (fjinmr drup*y) isof n vary different tv|*% f«*r hi^rr thr «rdms;i takm thr fnnn ofan nuiependrftt diMMs**. I*ir.t4 thrn, w«* nnmt Mudy the

ral symptom* am! tin* patluilni;ir4l f Jangrt wlitcb entitleto li#yk upon tins di »i%€ a% an mdependcut entity.

MALNUTRITIONAL OEDEMA 273

Numerous reports are available for this purpose, based forthe most par t on the work of German investigators.

According to Jansen,684, 1061 ^ d to Burger ,^ , "17 apartfrom the dropsical effusion in the subcutaneous tissues andin the various organs and cavities of the body, the mostprominent symptoms are bradycardia, anaemia, and hydraemia,polyuria and nycturia, a lowering of blood-pressure to 65 mm.or less, hemeralopia, and a lowered temperature. Schitten-helm and Schlecht9°9 draw special attention to the markedslowing of the pulse during repose. In most cases, too, thereis extreme emaciation.9°a

2. PATHOLOGICAL ANATOMY.

The most notable features on post-mortem examinationare the almost complete disappearance of the fatty tissue,even in the case of the viscera,9°9 and the atrophy of theparenchymatous organs. IO37, »>6if 1340 i n especial the heartand the liver are very small, and sometimes show signs ofbrown atrophy. The liver and the muscles are as a rulelacking in glycogen. Jansen stresses the atrophy of thethyroid. The activities of the pituitary body and the adrenalsare arrested IO37» I 3 l 6 ; the adrenals are usually hypertrophied.McCarrison actually declares that in oedema he has found theadrenals thrice the usual size, but he is probably referring tocases of beriberi.I3I5

The most notable characteristic of the blood is hydraemia.In consequence of this, the refractive index is greatlyreduced il6> I2J7 and the specific weight is also much lowered.The dried residue may be as little as 20 % or even 15 % of theaggregate blood.IZI7 As a rule, the water is about 10 % abovenormal, and therefore the protein concentration is reducedboth relatively and absolutely.716 On the other hand, theresidual nitrogen may be normal, or may be increased byas much as 30 %.7l6> 9"> *°61, ia l7 Feigl 7X* found in patientsstrictly dieted in institutions that there was hypoglycaemiato an average extent of 40 %, but tha t when the patientswere able to feed as they pleased the ratio of sugar in theblood was extremely variable. Schittenhelm and Schlechtfound that the sugar content of the blood was usually normal,but sometimes rose to 0-26 % 911; on the other hand, in one

18

274 VITAMINS

case Jansen found tha t thviv was only o•<•;".'*« IIu*acids in the blood ait* considmiblv unit*** *I,*I#* and w» j * fhr»aggregate fat.1*1? Atroulinu to Jaii^n,*'** tin* ufi.t t*,nfr?jtis normal. The lipoid phusphmu. u n«lu*« 1. ' ; W3 but Ita**acid phosphorus is inneased. 1 h«# h a u m ^ l n b m n«hm . ofthe blood varies greatly, and M> «lur» the I4*«»i totml both <4the erythrcxrytes and of thr I rmmjf t . lh* a* t u*nr Minimiof the blood is always somewhat itu x< a <d J*

According to Ffifjl,?16 t h t r r u in tn<»4 « . n . ait n n r r a ^in the kreatin richness of tin* WIMHI. at an\ i.ifr in fli«- «%n3ystages of the disease*, but a d^thiw ut tin kt« ^tnnn ri«hn»"*.In conformity with this In* iintl*, a» a ful*. an u i^ i i *4ammonia richness. Relafivvlv, t!t«* U*< rU<*h Una in tUrblcx)d is usually incrousrcl, tht»u;;h tint* m-n 1 ^ a «I««hu» mthe absolute quantity. Choir ,t#*rm ^ l » r a J«»tm*l m ahiu'i-xnally small quantitifs. Ihvn* u »J»HIWJH. »I ittMtincrease in the amounts of stulnun <h\<*it*\*4 t*%Umm4

sulphates; but there may Aha }»• a falling «*rf in th»- amof calcium. Iron, ami e^pmaUv tdhintn, ai*notably diminishecl. flht^i- njM>tt% ,ir^ t nadequate to the contemporai v (lan»laiil. «analysis! |

Very little inforniattou JM^ Iw«n j»tiWi Ji«*I s^ardtiif; ttw?composition of the in in** m I.IM , of inatttMtut^'iial *t*tlrnuAll investigators an* a^rerfj that the »i«i«htv '4 tli* tinnr t%extremely variable, In a r«t«-atth *4 mv *»^«. I fMuml 4great increase in the atismnnia n*hm * *i ih^ t inur iilirammoniacal nitrogen inmmnnmt \u u- "„ «4 th«* f^ial infi* ^n i )with a reduction in the tin a mtim-sH A little *%t*%u%w *&&%present. Feigl v*> also \mm\* out that tin ntmr ti>»u*»!!ycontains kreatin.

Corresponding with thf atrophy n4 tl*«* $UmU4 ilur* $* ngreat falling^off in the activity of f h r ^ organ*, ami inlong duration then* may br ,trh\li.i*»» Ihi^frequent occurrence of gantm iritrHtmaJ tlj«*rtlm

i n% m&< ***7

3. Pit

Generally sfieaking, the prognwuw IA (avuitf4Mr, inkn*cardiac oedema should develop, wliklt 1* f d k w « J by dc*«tti

MALNUTRITIONAL OEDEMA 275

from heart failure. The first essential of t reatment is restin bed. Next in importance comes a change of diet, bu tviews as to what should be the nature of this change varyfundamentally, the variations depending on the differences ofopinion presently to be discussed concerning the dieteticfactors of the disease. Some insist tha t the supply of proteinsshould be improved; others emphasise the importance of abetter supply of fats or carbohydrates or both. Some thinkthat to increase the vitamin in the diet is of no ava i l ; othersstress the need for the provision of a sufficiency of B ; andso on.

4. METABOLISM.

a. Nitrogenous Metabolism.

Passing to consider the; details of metabolism in thisillness, we find Nixon l558 reporting that the nitrogenousbalance is maintained. Janscn loC" and Burger »*7 found anegative nitrogenous balance in cases where the supply offats and carbohydrates was inadequate, and Burger claimsto have noted a moderate decline in the protein turnover.This last may perhaps be connected with the fact observedby Schittenhelm and Schlctcht?12 that in persons sufferingfrom nainutritional oedema the organism manifests an intensenitrogen hunger, and that for this reason the utilisation of theproteins in the food is comparatively effective. No notableabnormalities have been noted in the fat or the carbohydratemetabolism. Observers have been unanimous in recordinga markedly negative calcium balance ; and Burger also refersto the phosphorus balance as negative.

b. Sodium-Chloride Metabolism.

An in all varieties of oedema, interest has been mainlyconcentrated upon the sodium-chloride metabolism. But inthis connexion the medical publications referring to the matterhave repeatedly displayed lamentable ignorance of long-familiar facts concerning the way in which the various ionsact on the urinary apparatus. For more than th i r ty yearswe have known that the sodium ion has a paralysing effectupon the activities both of the kidneys and of the ureters*

VITAMINS

ami art* inl ine to th»* moie tetent f thot irh i M **» v u v ren*nt)researches of American physio logies tins r» e i j iu l l v tin*- «»fthe chlorine ion. Kove, moreover, has pmv«d hy «*xj*'fi*ment *?• 7" that when tht; organism is |«H*r in '<«huin »J.I<»n*!»\dmage wi th this salt reduces the «-xir«-ti«»n «»! nun**. 'I hediscoveries of Magnus Levy*1 ' '* have th*tefore *-\**i%*w tv* nu»r**than ronf tnn farts tha i have h>n^ i i r u i e.taMi'l*«*«l In mvown writing** i have ahvav^ nro^ti-d that th«* rx<fr?j«»n c»fsoditiin chlfitifli* in n slaw l»nsines.s# and that in |« r**<*f»s u h ^have heen nfv\vi*mu(\ tr* rnn-ajnif an ,U»ut)*!an*r i f i«4nm<*nsalt, immths at yr;\t\ ni f!«-|>n\.tti<#n tun t • 1-«LJf-*• J»{« i r thestores r»f sc*ditnn (h lo r id^ in the |x*!v ate *!* j»J*-t*-«J If jn.ivtheri'fr^re l>e tak<*n as a ni.i\t**t «4 <«»iir'i« tL.it whrn *^^!*-ni4si*ts in in a person \vhr*M- diet c<*nt.tm* .1 hi ^x.il M{J*J»JV «*Icamnum salt, there wi l l always I*1 a f«t«*ntit<n «»f thr . 'nbstance in the \HH\\* AS a watte* t»i r x j ^ i K i ^ e , all «*!'"< r\*-fHare agreed t l u t in itta!nutut3*jna] rK-d'-ma th«re r. 4 j**!*-ijti«»nof smlitl in < hlfilifJe by the !*M»1V, and that %%b<*Jt t h ^ ^rcfrin.iMll)sides there ip. a profuse exrretjotl *i th<" l-4f l 'ut | ; r tnoted v»* that when the ru-di-ma w.r* ' * t f i f , r tut i h r t r *i,r-niarked navinj i ; fr»r '.<f>*huin «h l " t i ' l * \ altX2 gramme'* wej r t»eintf m t v u n ^ d d-uJvdotihtlt**.'* i* that dtirmi* th»- t4t«*t *4m during that of all the ma!a<h«"» d'-jwrnd^nt uj^«n an i l l*k t l a m t t l diet, there ^t^bullx Atr^\ .% \<,-.\ <*t ^ j ^ t i f t * ,find sometimes a |K4,itivr Irathini* f >r 1***1« the j>4iirnithen attempts to ' . tumiUte np|«<'tite by *»vrr

ffJOtl.For the rrf-t> if would 'een$ th.tt \M'mm*hh*tt4^

Nth sin i** normul duntu ; inalnti tr i t iuri ' t l t«i-<Jrui.t ;Srhitt«*nJiehn and Nh1e*hOf t h f salt J% 'OlliewJi,!! letatderj if! tht*' rifsr^is^, %rfVt\t o ronftrm the f . | / i . Kn .uk and Xntm4ii«>*»ami Knthstesn | t t | s .in* airrrrd that th r wt-t t™}nf wa t f r dm^ not promotr* the trtmUon *4 «r.it«*t. ati4 O u tth r iw la t rd Ar!minr.tr«itpromntf! the retention of '.rhloridt* i i g ivrn in wateryl ion of l ioth wfttrr »nd *ioititim

MALNUTRITIONAL OEDEMA 277

5. DIETETIC FACTORS OF THE DISEASE.

a) The pathogenic Diet.

Opinions are diametrically opposed concerning the natureof the pathogenic diet. There is hardly an assertion in respectof this which is not disputed by some rival authority. It isobvious that the personal bias of the various writers has playeda considerable part in dictating their respective assertions;what one describes as an abundance is referred to by anotheras a quite inadequate quantity. Most observers are agreedin stating that the calorie content of the pathogenic diet istoo low 684, 9°*. ™i* ™58; but according to Schittenhelm andSchlecht,9« this has not always been the case. We are oftentold that the supply of protein has been too small,9°^ 91*. "96>»*5, 1258 the daily amount ranging in these instances from41 to 74 grammes. According to Liebers,IO79 however, theprotein content of the diet was sufficient: in peacetime theamount of protein in the hospital diet has been 77 • 33 grammes ;in 1916, it fell to 50-53 grammes; in 1917, it was 60-26grammes; and in 1918, it was 71*05 grammes.

Many authorities incline to regard an excess of carbohydratesin the diet as injurious 9°*> I3I7 ; but Jansen 684 reports a cureby a liberal supply of carbohydrates. Others consider thatthe fats in the food were deficient.91*, Io64 According toBurger,lal7 it was not always possible to demonstrate thatthe supply of inorganic salts was inadequate.

German writers in general are agreed in insisting thatthere seemed to be no lack of complettins in the diet 639> 9°2»912, IO64J 1235, **5»; whereas the British authorities refer to thelack of accessory food factors IO37, ™s6 ; and according toBurger lai7 the complettin content of the food was primarilylow, and the deficiency was often exaggerated by faultymethods of preparation. Kohman Io86 and Nixon "58 stressthe disproportion between the richness of the food in waterand its lack of solid constituents. Kohman, working aloneand also in collaboration with Denton,784 saw dropsy arisein cases in which carrots were being consumed in conjunctionwith an abundance of fat or starch, but in which a cure resultedon the administration of casein and calcium salts. Thereports of H. de WaeleIX96 and Burger 9°* contain typical

278 VITAMINS

instances of diets leading to malnutritional oedema. AIT 01 dingto de Waele, in a I ; ienrh ahn^houM* tin* dn t <*>tvi t« •! ofsoup and bread, or soup and potatoes, with b».m- .*n«i fattwice a week. In Huiger's case?*, the pathn^f nu <lie! wascomposed of bread, vegetables, and a SIIMII quanti ty ofpotatoes, with a little lard, and small amuunt . of pitkUdor salted meat.

There is general agreement that strenuous ph> ical labourpredisposes to the disease. B u r g e r s (see ai-u ur<) »ut»sthat among persons consuming the same amount *4 t a l e n t s ,those who did the hardest work were tin: hist to fall ill , andthat when the supply of calories vaiied, the pii^nns uimsi*diet was most deficient in this respect weir the JILSI t»» U<<*mt*affected with the disease. As in the case of jsruivy, pri di }*•»!-tion arises from anything which increa,s«*s the budiiy needs(hard work, very cold weather,6 # febrile disorder) , and ftomanything which tends to hinder absorption (gantiu mtv l u a ldisorders).

h. Wartime Feeding.

Sporadic cases had occurred eailier but nialnutttttoiuloedema first assumcnl an epidiinic prevalenn' in (#rnu*myduring the suinmtT of 1917,*^ when thr ciu*t of the |M**pii:was characterised by a lark of fats, high-grade piut ims, JHII.Itoes, and fresh vegetables, except for k< UIVAU\9 which w»taabundant. During tht* htib.secjucnt years, ilw t*ynvtAl elm,and especially the diet in institutions, WAS still griMlly l*itkifigin fat, high-grade prc»t<-tn.s, \x$UtUn*s, mid it* >h vvf>vUthh%,whereas cereals (which had to a considerable rx t rn t \*-vndegraded in value- .see above p, ju)t kobhabi, and w r ypoor soup-powders or vmp-tablcts, and dneel \u%rl»t\Ar\predominated. To complete the picture it k nt«crv»,ity tomention that as a rule, and doubtless invariably in iitstitultoiuit

the !>oiling of the kohlrabi wa« excr^ ive , and that t h r waterof the first tailing WU H thrown away ; alno that in tht* factorypreparation of dried vegetable*, the fre>h vrgiiitblrsbeen treated with steam before drying.1** We munt \moreover, that the abundant consumption of kohlrabi indue n lin many instances hevert* intetitinal iirituticm, whereby theutilihution of the food was greatly i

MALNUTRITIONAL OEDEMA 279

c. Prison Dropsy.

So-called famine dropsy or malnutritional oedema is byno means a new disease. As long ago as 1907, Hoist 65pointed o u t tha t , in the beginning of the nineteenth century,dropsy w a s exceedingly common in the jails of Europe andNorth America (see also *554), so that, among the causes ofdeath in prison, dropsy sometimes took the first place. Big-land, I0?7 w h o studied malnutritional oedema among prisonersof war in Egypt , was able to compare the disease with thefamine d r o p s y he had seen in India, where it has long beenknown t h a t dropsy is a common sequel of the frequentlyrecurring famines.

d. Ship Beriberi.

Hoist and Frdlich,65 who have studied the old reportsconcerning prison dropsy, consider it to have been identicalwith t h e so-called ship beriberi. Rumpel and Knack 571have c o m e to the same conclusion. Nocht,43 who is thegreatest au thor i ty on ship beriberi, gives a description of itwhich assimilates it in every respect to famine dropsy. I talways r u n s a chronic course, and even in the comparativelyrapid cases it lasts for several weeks at least. The initialsymptoms are nausea, lost of appetite, constipation, andgeneral deb i l i t y ; then comes the characteristic oedema,beginning in the feet and ankles, and slowly but surely spreadingupwards. Ultimately, owing to the extensive swelling andthe consequent palpitation and dyspnoea, the patients areforced t o take to their beds, and die from heart failure.Associated symptoms in many cases are severe gastric dis-comfort, gastralgia, and even hacmatcmesis. Among nervoussymptoms , hemeralopia is common, and there may be alsoslight puraesthesias in the feet and legs. True paralysis isran*, a n d when it occurs may perhaps be due to a complicationwith genuine beriberi ; just as an eruption of vesicles in themouth, a n d the tendency to moderate haemorrhages, some-t i m e ••*<•<• n in ship beriberi and famine dropsy, suggest acomplication with scurvy. The only point in which shiptH'riiwi resembles t rue beriberi is the," occurrence* of paraes-O»t*Mas in the former as well as the l a t t e r / b u t these are by

28o VITAMINS

no means characteristic*. Everyone who has to sit still fora long time is familiar with the onset of such paracsthesias,which may become intolerable even in healthy persons.

This description of ship beriberi seems a mere plagiarismfrom the description of famine dropsy. There can be nodoubt that prison dropsy, ship beriberi, and the malnutritionaloedema of the war years and of the Indian famines, are oneand the same disease. The treatment which is found mostuseful for ship beriberi confirms this supposition, for herelikewise rest in bed is the first essential and change of dietthe second. Jus t like the patients suffering from malnutri-tional oedema, those affected with ship beriberi recover withmarvellous rapidity, so that they can be discharged fromhospital in a week or two, and in slight cases can even resumetheir work on the ship after four or live days. In 190B, a tthe first congress of the German Society for Tropical Hygiene,Nocht 74 pointed out tha t even in Germany at tacks of illnessresembling ship beriberi were by no means rare, and mus tbe due to defective nutrition.

A. W, McCann «5M gives a graphic description of the fateof the (ierrnan accessory cruiser " Kronprinz Wilhelm/*which, after a raiding voyage which hud been successful fortwo hundred and fifty-five days, had to surrender to intern-ment in the United States because tint spread of ship beriberiamong the crew had mack* it impossible to manoeuvre thevessel any longer. But McCann is mistaken when he supposesthat wholemeal could have prevented the tremble, for thenscurvy would have taken the place of malnutritional oedema*This warship was conquered by the food-preserving industry !

The diet which induces ship b e r i h m is closely akin t othat which causes malnutritional oedema. It consists offlour and bread, peas ar beans, dried potatoes, tinned orsalted meat, and preserved vegetables* In German experiencethe disease usually makes its appearance on shipboard whenthe store of frosh potatoes has been exhausted, and the crewhas had to be fed on dried potatoes for a time. Hoist andFr6lich*5 and Schaumann,1** who record this observation,state also that the continued diet of preserved foods soonbecomes so distasteful, t ha t many of the crew restrict theirconsumption to a few articles (especially bacon, bread, mea t ,

MALNUTRITIONAL OEDEMA 281

and preserved vegetables), so tha t a diet already ill-balancedis thereby yet more restricted. The same phenomenon hasbeen noted in many cases of malnutritional oedema in Ger-many. Moreover, every doctor will be able to recall fromhis personal experience the cases of a number of neurasthenicpatients who lived on some such extremely restricted dietin the conviction tha t they could not tolerate other foods.

Arneulle Xi28 maintained as recently as 1920 tha t malnutri-tional oedema in Germany occurred only among the prisonersof war. This gross misstatement must, of course, be ascribedto the war psychosis, by which, unfortunately, other notedscientists have also been afflicted.

6. CONTRIBUTORY CAUSES OF MALNUTRITIONAL

OEDEMA.

a. Microorganisms.

From time to time it has been contended tha t malnutri-tional oedema must be due to microbic infection, but thedietetic causation of the disease is so obvious tha t suchtheories have never secured wide acceptance.

Jiirgens 5°* considers tha t malnutritional oedema is directlyor indirectly due to infection. H e holds t ha t the ill-balanced diet gives rise to gastro-intestinal disorders, andthat microorganisms may then invade the tissues, or mayproduce toxins which are absorbed from the alimentary tractand thus injure the tissues so as to give rise to oedema.

Writing in 1917, Nocht,637 in view of the then state of thecomplettin doctrine, left the question open whether shipberiberi was the outcome of a special form of malnutrition,or of an intoxication by damaged nutrients or by otherpoisons, or of some form of autointoxication.!! Wuth 88°considers that the cause must be a t rue toxin, quite distinctfrom haemotoxin, and characterised by marked lecithinophiiia.Smith 479 in like manner assumes autointoxication to be thedirect cause of glaucoma, a local oedema.

b. Inadequate Supply of Energy.

Most authorities on diet are prone to regard a deficientsupply of calories, and the consequent disintegration of the

282 VITAMINS

bodily tissues, as the main cause of malnutritional oedema.684»902, 1217 We have seen, however, that malnutritional oedemamay arise in persons whose diet has a fully adequate caloriecontent, and we are therefore forced to conclude that caloriedeficiency can at most be an accessory factor, one which maypredispose to the disease and may reinforce the noxiousinfluence of the main factor. A general deficiency of nutritionhas been assigned as the cause.639> 91*, 9*3 But by parity ofreasoning this can be no more than an accessory factor.Absolute starvation does not cause oedema. Some authoritiesrefer to protein insufficiencyio86 or inadequacy 784, 90* as themain cause, but others contest this view.IO78, "96 One authorityconsiders that an insufficient supply of carbohydrates is themain dietetic defect,1061 whilst others speak of an excess ofcarbohydrates as responsible.90* Burger, I2I7 who believes aninsufficiency of calories to be the main cause, thinks also thatan ill-balanced diet containing an excess of carbohydratesmay favour the onset of malnutritional oedema by its tendencyto promote the retention of water. [The carbohydrates arenot stored up in the body, and therefore cannot promote theretention of water in the tissues; on the contrary, it hasoften been possible to detect the presence of hypoglycaemiain this disease.] Whereas Maase and Zondek Io64 regard alack of fat as the essential cause of the disease, Jansen Io6r

reports that although the supply of fat was sometimes insuffi-cient, it was in general adequate. Bigland IO37 speaks ingeneral terms of an insufficient and ill-balanced diet, withoutsaying precisely in what way the food was defective. Knackand Neumann 639 lay the blame upon the excessive ingestionofjfluids by persons taking an ill-balanced diet. Kohman Io86

and Nixon I258 advocate the same theory, without troublingto reflect how innumerable are the persons who consumevast quantities of water or other fluids without being troubledwith oedema, provided only that the kidneys are healthy.Denton and Kohman 784 are inclined to regard a lack of calciumin the diet as a possible contributory cause.

c. Complettin Deficiency.

Most investigators, as I have already said, incline toexclude a deficiency of accessory food factors as a cause of

MALNUTRITIONAL OEDEMA 283

malnutritional oedema.639,9°*, 9^, Io64, i«5. 1258 i t would seem,however, tha t a lack of real knowledge of the accessory foodfactors has led many of these authorities astray, for it isplain that in a number of instances they are thinking only ofFunk's vitamin. Sometimes a contention has been putforward which is in manifest conflict with the data reportedby the assert or himself. For example, Burger 9°* rejects thetheory that a lack of " vitamins " can have caused the diseasewhen the diet consisted of bread, pickled meat, salted meat,lard, kohlrabi (which had obviously been boiled in the usualmanner), and a little potato—this being a regimen practicallydevoid of all accessory food factors ! Kohman Io86 will nothear of a lack of A as a cause, finding that to supplementthe diet with an abundance of butter makes matters worse,whereas an abundant supplement of B does not increase thedropsy. McCarrison,I34<> on the other hand, insists tha t but tercontains a substance which has an antidropsical effect, andfinds that the richness of butter in this substance runs parallelwith its richness in A. Elsewhere McCarrison IO56 states tha tthe lack of B in the diet is momentous; it almost alwaysleads to gastrointestinal disorders, to dysentery and diarrhoea,which culminate in oedema. In another publication, Burgerpoints out tha t in the diet which induces malnutritionaloedema the quantity of complettin is usually very small,and may be further reduced by various methods of preparation(excessive or unduly prolonged heating, the pouring away ofthe water in which the food has been boiled); consequently,we must not reject the possibility tha t an insufficiency of" vitamins " in the food may be an etiological factor. WhenSchlesinger Il65 refers to neuritis as a complication, and whenNocht refers to scurvy as a complication, it is obvious thatthere must have been a lack of complettins to produce theseintercurrent disorders, and tha t such a lack may thereforehave had something to do with inducing the malnutritionaloedema as well. Zambrzycki I I 6 2 regards malnutritionaloedema, scurvy, and beriberi as nutritive disorders whichhave a kindred etiology. He says that the same symptomsare common to all three diseases, the difference being theextent to which this or that symptom predominates. Inberiberi the pareses are most conspicuous; in scurvy, the

284 VITAMINS

symptoms of the haemorrhagic diatheses give the specificcharacter to the disease; and the most notable feature ofmalnutrit ional oedema is, of course, the anasarca.

d. Malnutritional Oedema akin to Mehlnahrschaden.

Many authorities draw attention to the resemblancesbetween malnutritional oedema and Mehlnahrschaden; amongthem I may mention Burger,9°* Schittenhelm and Schlecht ,^and Maver.la*5 This is in conformity with the foregoing,inasmuch as a lack of complettins plays its part in the causationof Mehlnahrschaden. Funk 3 8 has definitely classed Mehl-nahrschaden among the avitaminoses, using the latter termin the wider significance in which it is still current to-day (asequivalent to acomplettinoses). But in the review of Funk'swork in the " Zentralblatt fur Biochemie und Biophysik "(1914, 16, 758), the reviewer, who is a medical practitioner,is strongly opposed to the idea that Mehlnahrschaden,Milchnahrschaden, rickets, and spasmophilia are to be regardedas deficiency diseases.

There are certain respects in which Mehlnahrschaden isdefinitely distinguished from malnutritional oedema. Firstof all, whereas in malnutritional oedema there is a greatrelaxation of muscular tone, in Mehlnahrschaden the musclesare from the first hard and hypertonic. Furthermore, inMehlnahrschaden there is marked nervous irritability whichmanifests itself in the proneness to muscular spasm, andperhaps assimilates the disease to spasmophilia rather thanto malnutrit ional oedema. For in malnutritional oedemathere are no nervous symptoms except for the occasionalparaesthesias, and even these are probably a secondary out-come of the mechanical pressure exercised by the swollentissues on the nerves. I t is no more than a chance resemblancetha t , in the long run, atrophy and oedema may becomeassociated in both diseases.

7. CAUSES OF DROPSY.

a. Chemical Causes.

Obviously, by the routes hitherto followed there is nohope of reaching a clear conception of the etiology of the

MALNUTRITIONAL OEDEMA 285

disease. We shall do better to set out from a study of themorbid anatomy, and to enquire how, in the given cases, theoedematogenic diet can have induced this. What we haveto consider is not any mechanical lesion of the capillaries,for that would lead to a haemorrhagic and not to a merelyserous infiltration of the tissues. We are concerned with achemical lesion of the capillary walls, and with an interferencewith the flow of blood through the venous system. Such aninterference, for instance, as results from a great lowering ofblood-pressure, causing passive congestion. We have also tothink of a true hydraemia, a decline in the internal pressureof the serum, dependent upon its excessive dilution, leadingto a so-called dyscrasic oedema of a general character—toanasarca.

b. Oholesterin Impoverishment.

A chemical injury of the capillary walls, just as in thecase of the walls of the larger bloodvessels, may arise in eitherof two chief ways. The first of these is by a disappearanceof the lipoids from the cellular walls, which makes them morepermeable by watery solutions. Such changes ensue when,in especial, any of the cholesterin compounds are lacking inthe cells of the capillary wall, either because there is a generalimpoverishment of the blood in respect of these compounds,or else because the solubility of the compounds in blood-serumis increased.

Such a disappearance of the cholesterin esters is especiallynoted in diseases in which, in conjunction with a hindranceto the new formation of such esters, there is a hypertrophyof certain organs very rich in these compounds—notably theadrenals. In the deficiency diseases in general, and in malnutri-tional oedema in particular, there is such a hypertrophy ofthe adrenals. More particularly we know tha t in mal-nutritional oedema this hypertrophy is attended by a fattydegeneration of the adrenals, which means tha t these organsare overloaded with cholesterin esters. That change alone,however, cannot give rise to impoverishment of the blood.There must simultaneously be some interference with a newformation of the cholesterin esters in the blood. But wehave no evidence of anything of the kind in malnutritionaloedema, for the oedematogenic diet has usually contained

286 VITAMINS

an ample supply both of free cholesterins and of cholesterinesters. Moreover, Albrecht and Weltmann (" Wiener klinischeWochenschrift," 1911, No. 14) have proved that in mostcases, when the cholesterin content of the blood declines—as it will tend to decline from time to time when this substanceis deficient in the food—the adrenals readily surrender partof their store of cholesterin esters.

A second way of inducing cholesterin impoverishment ofthe capillary walls might be that there should be an accumula-tion of lipoid-solvent materials in the blood; but in thatcase there would not be a deficiency of cholesterin compoundsin the blood itself, such as we find in malnutritional oedema ;there would rather be an excess of cholesterins, such as isknown to occur in dogs during ether anaesthesia. (Cf. Bang.5<>8)I t follows, therefore, that the before-mentioned occurrenceof acetone in the blood can have nothing to do with thequestion we are considering, although acetone is a lipoid-solvent.

Much more important is another consideration, a factwhich has again and again been demonstrated. The ratiobetween cholesterin compounds and neutral fat in the bloodis remarkably constant. If for any reason the richness ofthe blood in neutral fats should decline, there is also noteda decline in the amount of cholesterin bodies in the b lood;and when the proportion of the one class of substances in theblood increases, the proportion of the other class increasesalso. This might explain why the blood is poor in cholesterinwhen the diet contains too little fat. But since, as far asmalnutritional oedema is concerned, the oedematogenic diethas often been shown to contain an abundance of fat, wecannot look upon this cause, either, as accounting, in general,for the cholesterin impoverishment of the blood, and thusindirectly for the origin of the oedema.

There is, however, a persistent factor in the clinical picture,one which might lead to a lack of fat, and consequently toa lack of cholesterin, in the blood. We have already seenthat in malnutritional oedema the digestive glands do theirwork badly, so that sometimes there may be more or lesscomplete achylia. This will make it impossible for the absorp-tion of fat and cholesterins from the intestine to be effective,

MALNUTRITIONAL OEDEMA 287

and thus the known impoverishment of the blood in fat andcholesterin compounds is easily explicable as a result of thedisorder of digestion. But since the blood still retains itspower of dissolving the cholesterin compounds, it will dissolvethem out of the vascular walls (and they will then be with-drawn from the blood for storage in the morbidly hypertro-phied adrenals). This mechanism may account for the onsetof general oedema.

But the factor we have just been considering can onlycome into operation in the later stages of the disease. Whensuch an impoverishment in cholesterin bodies gets t o workas a cause of oedema, it must promptly induce universalanasarca. We have learned, however, tha t the oedema comeson gradually, beginning in the feet and ankles, and extendingupwards by degrees. Not until the final stages does universalanasarca ensue.

c. Anomalies of inorganic Metabolism

A second way in which a chemical lesion of the capillarywalls may arise is through the instrumentality of the meta-bolism of the inorganic salts. Here we have three possibilitiesto consider. First the blood may be relatively or absolutelyoverloaded with sodium ions ; and secondly it may be impover-ished in respect of calcium ions, for this impoverishmentwould have a similar effect. In both cases there may ehsuea transudation of serum from the blood into the t issues;whereas, conversely, when the blood is comparatively poorin sodium ions, or fully supplied with calcium ions, serum willtend to pass out of the tissues through the vascular wallsinto the capillaries. To understand this we have to rememberthat, even under perfectly normal physiological conditions,fluid is continually passing from the blood into the tissuesand from the tissues into the blood. This transudation,however, is not a filtration; nor is it, mainly at any rate,the result of osmosis. I t is due to secretory activities on thepart of the vascular endotheliurn, which, both from the bloodand from the tissues, incorporates substances in solution,and then selectively passes them on to one side or the other.This endothelial activity is paralysed by an excess of sodiumions, and on the other hand it is stimulated by a sufficiency

2 88 VITAMINS

of calcium ions. Oedema can be induced by an excessivesupply of sodium ions; and, conversely, absorption fromdropsical tissues can be promoted by the supply of calciumions. (I should mention that the absorption of dropsicaleffusion from the body cavities is not furthered by the supplyof calcium, which has an unfavourable effect here).

But there is a third way in which variations in the meta-bolism of inorganic salts may injuriously affect the vascularsystem. We know that the effect of acids on the walls ofthe bloodvessels is to induce swelling and hyaline degeneration.Even free carbonic acid may have this action. Now, theoedematogenic diet always contains an excess of inorganicacids, so that there must be acidosis in malnutritional oedema.Moreover, the increase of ammonia and acetone in the bloodand the urine of these patients is a definite indication ofacidosis.

d. Effect of Hydraemia.

We have, then, found an effective cause for the occurrenceof dropsy in malnutritional oedema, but we have to make thesame reserve that we made in the case of cholesterin impover-ishment. This disturbance of the metabolism of inorganicsalts would necessarily lead to general anasarca, such as doesin fact arise during the final stages of the disease. It follows,therefore, that cholesterin impoverishment and disorder ofinorganic metabolism can be no more than contributorycauses. What we are still in search of is some predisposingcause, which can account for the localisation of the initialoedema. But before we pursue this question, we have toconsider a third factor, which may very well explain theonset of the oedema, but itself in turn requires to be explained.I refer to the condition of hydraernia which is actually provedto exist—the general impoverishment of the blood as regardssolid constituents, and the undue richness of the blood inwater. Excessive wateriness of the blood must of coursetend to result, by osmosis, in the passage of fluid into thetissues, especially if there should be a lowering of the osmoticpressure of the blood. This latter change is not, however,associated; for in malnutritional oedema, thanks to theaccumulation of sodium chloride in the blood, the osmoticpressure is kept at its normal level—and in all the cases he

MALNUTRITIONAL OEDEMA 289

has investigated, Feigl 116 has found the cryoscopic conditionsnormal. Of course this means no more than tha t the relativesodium-chloride content of the dropsical effusion is normal.The impoverishment of the blood in respect of certain otheringredients involves a reduction of the partial pressure ofthese substances, which must lead to an impairment of theproper relationship between the blood and the tissue fluid.I n consequence of this, a transudation of serum will ensueuntil the partial pressure of these substances in the tissueshas become identical with tha t in the blood.

This explanation may seem most acceptable, bu t in realityi t merely thrusts back the problem a stage further, for wehave to ask, W h a t is the cause of the hydraemia ? Althoughmany authorities tell us tha t the wateriness of the regimen isthe cause, this is absurd. Provided my organism is healthy,it makes no difference if I consume a lot of watery nutriment,or even drink large quantit ies of pure water. The body hasits own way of dealing with an excess of water. The cardinalpoint of which we are in search is the explanation of thefailure of this regulative mechanism.

e. Cardiac Asthenia.

The regulative capacity of the organism in this respectcan, first of all, be reduced by cardiac asthenia. But thoughall authorities refer to the existence of bradycardia in theacute stage of the disease, this is by no means synonymouswith cardiac asthenia, and is probably a consequence ratherthan a cause of the increase in the quant i ty of the blood andof the fall of the blood-pressure. Furthermore, although thelowering of the blood-pressure may lead to a reduction inrenal excretion, i t can hardly account for the hydraemia.We must, therefore, direct our attention in the first place tothe organs preeminently responsible for excretion, namelythe kidneys ; we must enquire whether, in the pathogenicdiet, there are any factors competent to interfere with theprocess of renal excretion.

/ . Behaviour of the Kidneys.

In this connexion, once more, we have three symptomsalready known to us to reckon with—symptoms which are

19

2Q0 VITAMINS

somewhat conflicting, so that a satisfactory solution of theproblem is rather difficult. First of all there is the hydraemia ;secondly, the polyuria; and, thirdly, the nycturia. I t isdifficult to understand how hydraemia can arise when thereis polyuria, and when the polyuria is so marked as to leadto nycturia.

Polyuria is a familiar symptom in persons who consume adiet containing large quantities of water and also substancescontaining an abundance of inorganic salts, especially calciumand potassium salts. I t has been my experience tha t inpersons who have hitherto been little accustomed to a vege-tarian diet, and who therefore, when they consume considerablequantities of vegetable food, are prone to season it stronglywith salt, there is apt to be delayed excretion, so that theyare forced to rise several times during the night in order topass water. In proportion as the sodium chloride is eliminatedfrom the body, the nocturnal diuresis declines, and, on theother hand, the flow of urine during the daytime increases.In a healthy individual who consumes only moderate quantitiesof table salt (not more than 7 grammes daily) the kidneys actso promptly that after a liberal helping of watery vegetables,such as asparagus, young green peas, kohlrabi, or carrots,the desire to pass water becomes urgent within ten minutes.

g. The Effect of the various Ions on the Kidneys.

The hindrance to the natural excretion of water musttherefore depend on the effect of the sodium ion on the renaltissue. This effect is reinforced by the simultaneous presenceof the chlorine ion, which likewise hinders the activity of thekidneys. A deficient supply of calcium contributes to theretardation. In physiologically healthy conditions, calciumand sodium have contrary actions on the renal functions.Calcium, by its effect on nerve and muscle, reinforces thestimulating influence of the potassium ion. Sodium andchlorine tend to paralyse renal activity; potassium stimulatesand calcium regulates this activity.

In the oedematogenic diet, there is an excess of sodiumand chlorine, in conjunction with a lack of calcium, andfrequently with a lack of potassium. These conditions impairthe excretory activity of the kidneys, and simultaneously

MALNUTRITIONAL OEDEMA 291

tend to paralyse the sphincter vesicae. Consequently, anurgent desire to make water is felt even when there is but avery small quantity of fluid in the bladder. I t is a fact thatthese patients all complain of a frequent desire to pass water,although they pass only small quantities at a time (from 50to 150 cc) . Nevertheless, as Rose's researches and mine haveshown, despite the paralysing effect of the sodium ion onrenal activity, the consumption of large quantities of sodiumin the form of table salt (more than 12 grammes) inducesmarked diuresis. To understand this phenomenon, we mustremember that in the excretory function of the kidneys twodistinct factors are at work. The genuinely regulative func-tion of these organs depends upon a selective excretion; thekidneys are excretory glands, and it is, primarily, this excretoryactivity which is affected by small quantities of ions. But inaddition, the kidney tissue, like that of all other organs, issubject to the laws of osmotic pressure; there must be anosmotic equilibrium between excretion by the kidneys andthe constitution of the blood. I t is to this osmotic elementin the renal function that we must refer the increase in theurinary excretion when large quantities of common salt areconsumed. The bodily tissues are adapted for a specificosmotic pressure, and as soon as this pressure is exceeded,the ion whose partial pressure is excessive is automaticallyexcreted by the kidneys. But since, in this process, thegenuinely active function of the kidneys plays no part, itfollows that, as far as the excretion of other substances isconcerned, excretion takes place only in proportion as theblood passing through the kidneys is able to provide theactively excreting tissues of these oigans with a sufficiencyof the stimulating and regulating ions.

We have already learned that the excretion of sodiumchloride in the urine is always a tardy process, and the factsjust mentioned explain the retardation. They also enableus to understand that a sufficient excess of water and sodiumchloride may ultimately lead to polyuria although at thesame time the blood has become hydraemic. The secretoryactivity of the kidneys has been to a considerable extentparalysed, and nevertheless the excessive supply of sodiumchloride has raised the osmotic pressure of this salt so high

292 VITAMINS

as to promote diuresis. If the accumulation of water andsodium chloride in the body be considerable, the diuresis maybe excessive, and may be none the less inadequate to freethe blood from its excess of water.

h. The Reduction of Blood-Pressure.

A third factor has now to be considered, one competentunaided to induce oedema. In my account of the polyneuriticdisorders I referred to McCarrison's hypothesis that thehypertrophy of the adrenals led to an increased formation ofadrenalin, and that the resulting constriction of the capillariescaused an exudation of serum into the tissues. I quotedBarr, however, in support of the contention that adrenalinacts on the larger bloodvessels rather than on the arterioles,so that a surplus production of adrenalin must favour thecirculation and must tend to counteract the occurrence ofoedema. But in beriberi, notwithstanding the hypertrophyof the adrenals, the blood-pressure is low, and this leads toso great a flow of blood through the arteries that the outflowfrom the capillaries is insufficient. In view of these considera-tions, McCarrison has formally withdrawn his hypothesis. Inmalnutritional oedema, the fall in blood-pressure, the relaxationof the great vessels, is even more marked than in beriberi,so that on this count alone we should expect the onset ofoedema.

i. The Effect of B Deficiency.

But what is the cause of the fall in blood-pressure ? Thereare two factors, which work hand in hand. When studyingthe determinants of growth we found that vegetable extractsrich in B could induce a lowering of blood-pressure. Butthis factor is not in question here, for in malnutritional oedemathere is a lack of B in the diet, not an excess. However, thedeficiency of B may be the indirect cause, for it may act byimpairing the secretory activities of the endocrine glands.In the case of the polyneuritic disorders we saw that thisapplies to the production of adrenalin, for although the adrenalsare hypertrophied in these disorders, they do not supply anormal quantity of adrenalin.

MALNUTRITIONAL OEDEMA 293

k. The Lack of Potassium and Calcium,

The lack of B, however, cannot make itself felt quickly.There must be a considerable period of incubation before theinsufficiencies arising from this lack can induce oedema.But simultaneously with the B deficiency there is at worka second factor competent to bring about a relaxation of thebloodvessels. I have already shown that an excess of sodiumand chlorine ions in conjunction with a deficiency of potassiumand calcium tends to paralyse the vital secretory activitiesof the endothelial cells lining the bloodvessels, with the resultthat the interchange between the blood and the tissues ispredominantly effected by differences in osmotic pressureinstead of by the active intervention of the vascular endothe-lium. But the richness of the blood in these various ions hasanother direct influence upon the bloodvessels, upon thearterial walls this time. Jus t as in the case of the sphinctervescicae, the intestinal musculature, and the ureter, an excessof sodium and chlorine ions has a paralysing influence uponthe involuntary muscular fibres in the arterial walls. Thisaction is reinforced by the lack of the corrective influenceof the calcium and potassium ions. Consequently, the excessof sodium chloride and the deficiency of calcium and potassiumin the blood must lead to a relaxation of the arterial muscula-ture, and this will obviously induce a fall in blood-pressure.

8. SUMMARY.

Let us now summarise the foregoing considerations. Wemay regard as the primary cause of the oedema the declinein the secretory activity of the kidneys owing to the lack ofcalcium and potassium. Consequently the blood becomeshydraemic. The transudation of the hydraemic serum intothe tissues is brought about by a paralysis of the regulativeactivity of the vascular endothelium owing to the calciumand potassium activity ; also by the hydraemia ; also bythe relaxation of the bloodvessels consequent on the lack ofcalcium and potassium, which leads to passive congestion,and by other chemical changes in the blood and the vascularwalls. The passive oedema must make its appearance firstwhere the driving power of the heart has the greatest difficulties

294 VITAMINS

in making itself felt—in the lower, extremities, and notablyin the joints, where the circulation is especially sluggish. Thetendency to oedema is reinforced by the failure of the adrenalsto provide a sufficiency of adrenalin.

All these factors are brought into play for much the samereason. The lack of B in the diet, which leads to a declinein glandular activity, is responsible for the failure of theadrenals and for the consequent loss of arterial tone. Thedeficiency of lipoids in the vascular walls and the blood isreferable to the defective absorption of lipoids from the intes-tinal tract, and this, too, is an outcome of B deficiency. Afurther change in the vascular walls and in the blood is dueto the excessive consumption of table salt, and to the lack ofcalcium and perhaps of potassium ions. The degeneration ofthe walls of the bloodvessels is accentuated by the acidosisconsequent on the diet. Furthermore, the acidosis and theother effects of inorganic metabolism have a directly paralysinginfluence upon the arterial musculature, and also upon thesecretory activity of the kidneys; while the large quantitiesof sodium chloride, raising the osmotic pressure of this salt,induces a morbid diuresis, which nevertheless does not sufficeto clear the surplus water out of the system.

A study of the actual diet should, therefore, enable us toascertain the factors leading to oedema. There must be alack of B, a lack of calcium, and perhaps a lack of potassium,in conjunction with an excess of sodium chloride, togetherwith an abundant consumption of fluid. I t is possible tha ta lack of A may be contributory, for according to McCarrison I24°this complettin is able to hinder the onset of oedema. ButMcCarrison's observation has not yet been confirmed.

O. Bossert 10I4 reports a very interesting case bearingupon these theories. In children affected with spasmophiliaupon a gruel diet, a raw egg was added to make the diet betterbalanced. The consequence was the onset of oedema, mainlyin the feet and legs, but also to some extent in the face, andoccasionally carpopedal spasms were noted. The symptomspromptly disappeared when the eggs were discontinued.While the oedema was present, Bossert found that there wasmarked retention of nitrogen and inorganic sa l ts ; with thewithdrawal of the eggs, and concurrently with the disappear-

MALNUTRITIONAL OEDEMA 295

ance of the oedema, the retained substances were excreted.Bossert considers tha t local changes in the tissues with arelative lack of calcium in the interstitial fluid of the tissues,leading to an accumulation of chlorine and alkali in this fluid,must have been the cause of the trouble. Now the calciumimpoverishment preexisted, and since there is an abundanceof calcium in yolk of egg, the giving of the eggs ought to havehad a good effect as far as this matter was concerned. But,together with the calcium, there was introduced by the additionto the diet a marked excess of sulphuric acid and still moreof phosphoric acid, so that despite the absolute enrichmentwith calcium there must have been an increase in the relativeimpoverishment as far as this ion was concerned. Further-more, the acidosis already due to the gruel diet must havebeen accentuated. In these cases, however, there was afactor at work which is not operative in ordinary malnutri-tional oedema. Eggs are very rich in lecithins ; during thedecomposition of lecithins in the processes of digestion or inthe blood, cholin is liberated, and this natural antagonist ofadrenalin must give rise to a lowering of blood-pressure.Even though the conditions for the onset of oedema alreadyexisted, they did not become fully operative until a conditionof passive congestion was brought about by the action ofthe cholin. A contributory, and perhaps decisive, influencewas exercised by the deficiency of nervous tone in thesespasmophiliac children, and this perhaps explains why thesymptoms were noted in spasmophiliac patients only.

Pending fuller knowledge, we may therefore regard a lackof B, of calcium, and sometimes of potassium and A as well, inconjunction with an excess of sodium chloride, inorganic acids,and water, as the determinants of malnutritional oedema.

ADDENDUM TO CHAPTER E I G H T : K I N D R E D NUTRITIVE

DISORDERS.

a. Mehlnahrschaden.

We have already learned that various authorities 902-* 9J3, ***5consider tha t there is a kinship between the Mehlnahrschadenof infants-in-arms and malnutritional oedema. I t will thereforebe expedient to undertake a more detailed examination of thefactors tha t may contribute to the onset of Mehlnahrschaden.

2Q6 VITAMINS

It has been shown that at the very outset this disease isdistinguished from mainutritional oedema inasmuch, as inthe latter the muscles are relaxed and toneless, whereas inif ehlnahrschaden they are hard and hypertonic. Furthermore,in mainutritional oedema there are no nervous symptoms(unless polyneuritis be present as a complication), whereas inMehlnahrschaden there is a nervous hyperirritability whichmay lead to tetanoid spasms. Again at an early stage ofMehlnahrschaden, the little patients suffer from moderatemeteorism. By degrees, the nutritive condition grows worse,until ultimately a markedly atrophic state arises. In. thelast stages, there may be oedema. To complete the picture,it is necessary to add that acute gastro-intestinal disorderis a frequent complication. There is also a notable increasein the susceptibility to every kind of infection.

The diet in these cases has consisted mainly of gruel,mush, or porridge of some kind, to which sugar and fat areoften added to promote energy. The errors of such a dietfrom the standpoint of modern dietetics are obvious. Wehave learned that all the cereals have certain defects whichmay be looked upon as characteristic of these nutrients. Asregards inorganic salts, they are deficient in sodium and cal-cium ; they are also poorly supplied with organically combinedsulphur and with bases generally ; but they contain a super-abundance of inorganic acid-formers and of potassium. Thecereals are also poor in B, A, and C, the poverty being moremarked in proportion to the fineness of the flour. Finally,the proteins of the cereals are always inadequate; they arelacking to some extent in the ringed amino-acids, and areespecially poor in lysin and cystin. These defects afford aready explanation of the causation of the disease. Thedeficiency of A and B impairs the activity of the digestiveglands, so that the utilisation of a diet that is already inadequateis rendered incomplete, and at the same time the door is openedfor all kinds of intestinal infections and fermentations. Theexcess of potassium, when there is a deficiency of sodium asan antagoniser and of calcium as a corrective, leads to muscularhypertension, to contractures; and at the same time inducesa nervous hyperexcitability which manifests itself in tetanoidspasms. In most cases the lack of A in the gruel is fairly

MALNUTRITIONAL OEDEMA 297

well compensated by the addition of butter. When thissupplement is lacking (as in Denmark, where the butter isdestined for export) xerophthalmia often occurs as a complica-tion. This is supposed to be the chief cause of blindnessamong Danish children.940

The lack of complettins and of important inorganicnutrients, the acidosis, and in especial the lack of an adequateprotein, must gradually induce general atrophy, as the out-come of which the glands will be paralysed and atrophied,and more particularly the production of adrenalin will bereduced.ia4<> In the long run there will ensue a fall in blood-pressure, and this, in conjunction with the onset of cardiacasthenia due to the malnutrition and the lack of calcium,will give rise to oedema.

J. Milchnahrschaden.

Aron 388 protests against confounding Mehlnahrschadenwith Milchnahrschaden, probably with justice. Milchnahr-schaden, which is a rarer disease than Mehlnahrschaden, is aresult of the hand feeding of infants with milk, especiallycow's milk. Ordinarily, in this form of artificial feeding, themilk is greatly diluted and is also pasteurised or at leastscalded. The first symptom of the disorder is that sleep isgreatly disturbed; the infant is overtired, and manifestsits discomfort by repeated fits of crying. The skin becomespale and turgid, and is morbidly sensitive to injury. Thetonicity of the tissues and the blood-pressure decline; thestools contain large quantities of fatty soaps; and there ismarked meteorism. For a time there is an arrest of weight,and then the weight actually falls until extreme atrophy hasbeen established. Marked intolerance of fat is displayed,especially when cream is added to the milk in the hope ofimproving the nutritive condition.

Nervous symptoms have not been noted, but the diseasemay sometimes be complicated with infantile scurvy.

c. Fat as a noxious Factor in Infant Feeding,The fatty acids of the milk have hitherto been regarded

as responsible for Milchnahrschaden. I t has been supposedthat, as the outcome of some gastro-intestinal disturbance,

298 VITAMINS

the unabsorbed fatty acids have been eliminated in the stoolsas sodium, potassium, or calcium soaps, this leading to animpoverishment of the body in respect of bases.

Czerny considers that the volatile fatty acids in the milkfat are especially to blame, and therefore he and Kleinschmidtrecommend the well-known butter-and-flour preparation,made by heating butter with flour so that the volatile fattyacids are driven off. Reiche,1^ however, reports that childrendo not thrive permanently on this butter-flour diet, and thatultimately the increase of weight is arrested.

WTiile we may admit that a failure in the absorption offat may actually lead to the onset of acidosis, the symptomcomplex of Milchnahrschaden cannot be thus explained. Butthe knowledge we have now acquired concerning the physi-ology of nutrition should enable us without much difficultyto ascertain the true pathogenic factors in this instance also.In contradistinction to Mehlnahrschaden, the dominantfeature is here an impoverishment in potassium, and, thanksto the dilution of the milk, also in sodium and calcium, andin bases and inorganic nutrients generally. The deficiencysuffices to induce acidosis, and that condition can certainlybe aggravated by the losses due to the fatty discharge in thestools. But the acidosis does not suffice to explain thesymptoms, even though the impoverishment in respect ofinorganic nutrients must certainly tend to reduce the vigourof the vital reactions.

The pallor, the turgidity of the skin, the digestive dis-orders, the loss of tonicity of the tissues, the sensitiveness ofthe skin to injury, the weakness of the digestion, and theincreased susceptibility to infections, comprise a syndromewe have already noted when discussing the conditions ofgrowth, and we have recognised it to be an outcome of Bdeficiency. I have pointed out that the B content of cow'smilk is primarily low, and that therefore a dilution of cow'smilk must make the danger of B deficiency acute.

It is, of course, obvious that when there is a general lackof inorganic nutrients together with acidosis and defectivepower to digest fats, the symptoms of the disease can onlybe aggravated by increasing the amount of fat in the milkthrough the addition of cream.

CHAPTER NINE

PELLAGRA

r. CLINICAL PICTURE.

THOSE who speak to-day of the avitaminoses, or, as I preferto call them, of the acomplettinoses, have usually three diseasesin mind : scurvy, beriberi, and pellagra. A full accounthas been given of beriberi and scurvy, and it remains onlyto undertake a critical discussion of pellagra. The primaryrequisite in this connexion is a precise knowledge of thesymptom complex that passes by that name. The firstspecific feature is the chronicity of its course. At the outsetthere are slight attacks, chiefly in spring and autumn; andduring the intervals between these the manifestations recedeand may completely disappear. In the attacks, the patientexhibits a peculiar awkwardness of movement, which makeshis gait typically cumbrous. He complains of headache,dizziness, sleeplessness, weakness, paraesthesias, and neuralgias.He is listless, depressed, and irritable. Gradually, loss ofappetite sets in, sometimes culminating in a positive loathingfor his ordinary food, but occasionally alternating with,bulimia. The tongue is apt to be thickly coated, or in a stateof inflammatory desquamation ; there are salivation, heart-burn, often intense thirst and gastralgia; in many cases,diarrhoea completes the picture of severe gastro-rntestinaldisorder. The attacks commonly recur year after year,"becoming worse perhaps, but not exhibiting any other change.By degrees, however, upon this basis, there is superimposedthe group of serious nervous disturbances typical of advancedpellagra. Concurrently with their onset, in the spring orautumn an eruption usually appears. The digestive troublesbecome more obstinate, stubborn constipation sometimes

299

300 VITAMINS

alternating with diarrhoea. Emaciation sets in, and theaspect is now cachectic. Nephritis is common, and theurine (which is often alkaline from secondary infection of thebladder) contains albumin. When there is marked gastro-intestinal disorder, indicanuria is not uncommon. Anaemia,with moderate lymphocytosis, develops as a secondary symp-tom. Most characteristic of all are paralytic manifestations,often associated with nerve atrophy and with tonic or clonicspasm. The knee-jerks are usually exaggerated, but in somecases are absent; Romberg's symptom is generally present.The gait is that of spastic paraplegia. Vertigo, tremor, andtwitching are common; and the spasms may pass on intoepileptiform convulsions. Other typical symptoms are photo-phobia, retinitis, and at times disorder of the auditory nerve.Severe neuralgias and obstinate paraesthesias of the mostmultiform character contribute to the development of themental disturbance which often arises at this stage, and mayultimately drive the patient to suicide. The mental symptomsmay take the form of melancholia, mania, cyclic insanity,paranoid and obsessive ideas, etc. The apathy and theamnesia may affect the intelligence so profoundly that themental state comes to simulate that of paralytic dementia.

The parts affected by the exanthem are especially thoseexposed to light, and notably to direct sunlight. There is aremarkably symmetrical erythema, which may be light-red,dark-red, or bluish in tint. The affected areas are the seatsof a burning sensation, which is apt to be almost unbearableat night ; and vesicles or pustules often form upon the skinof these regions. This vesicular dermatitis gradually leadsto the formation of crusts, or sometimes to the onset of typicaleczema. After a number of such attacks of dermatitis,hyperkeratosis sets in, subsequently leading to markeddesquamation, after which the skin is left in a dry, raw, parch-menty, and deeply pigmented state. Ultimately, the skinbecomes shrunken, wrinkled, and atrophic. Striking as theeruptions are, they are not universal in this disease. Especiallyin America,I007 many cases have been seen of unmistakablepellagra without any eruption ("pellagra sine pe l l agra" ) ;and other cases in which the exanthem has been limited to theformation of scales, or to rhagades in the corners of the mouth.

PELLAGRA 301

I have already referred to the fact that the course ofpellagra is chronic. In the worst cases, it is true that withina few months or years death may occur from cachexia, orin consequence of the mental or nervous disturbances. As arule, however, the illness lasts for decades, and in exceptionalinstances throughout a life of normal duration.

There is, however, an acute form, the so-called typhuspellagrosus, characterised by pyrexia and a typhoid state,and by an accentuation of all the usual symptoms. Theintelligence is clouded at an early stage, and before longdelirium occurs. In contradistinction to the chronic form ofthe disease, in the acute form there is a hypertonicity of thewhole muscular system, sometimes so marked as to causeopisthotonus. As in severe attacks of typhoid and typhus,the patients are completely helpless, and pass the faeces andurine involuntarily. Death ensues within a week or two, tothe accompaniment of grave complications, such as pneu-monia, encephalitis, extensive bed-sores, etc. Notwithstandingthe onset of this typhoid state, no typical microorganisms havebeen found in the stools or in the blood in this form of thedisease; it is doubtless due only to severe complications inthe form of gastro-intestinal disturbances. The amoebaeof amoebic dysentery, various microorganisms, nematodeworms, etc., have been found in great variety in these cases.We may therefore presume that the typhoid state is the out-come of the association of the severe gastro-intestinal disorderand the malnutrition with the nervous symptoms characteristicof pellagra.

In the early stages of pellagra, a complete change of dietoffers the best hope of cure, though by no means a certainhope. Without such a change, and in advanced cases, theprognosis is exceedingly grave.

2. PATHOLOGICAL ANATOMY.

The first morbid changes take the form of congestion ofthe whole intestinal tract, passing on into grave atrophy,and often attended by ulceration of the large intestine. Thereare also degeneration and atrophy of the muscles, the heart,the liver, the spleen, the kidneys, and the endocrine glands.Whereas in the other deficiency diseases, the adrenals are

-p 2 VITAMINS

L * M : *r f*u d, in pellagra these glands are markedly atrophied,and may he reduced to one-tenth of their normal size.lr37,us- xi,: Degeneration is especially frequent in the medullaof the adrenals and in the Langerhans' islands of thespleen.

In the later stages, when the nervous and mental symptomshave developed, we find extensive and diversified changesin the nervous system. Most conspicuous are the signs ofinflammation in the meninges of the brain and the spinalcord. There is degeneration of the large ganglion cells in thecerebral cortex, of the posterior horns of the spinal cord, a n dof the ganglia of the posterior roots; less often there isdegeneration in the cells of Clarke's columns and in those ofthe anterior horns. There are also symmetrical degenerativeor sclerotic changes in the posterior tracts (especially in thecolumns of Goll), the pyramidal tracts, the lateral tracts, a n dabove all in the posterior roots. According to Roaf,IoS6 thecells of the ganglia of the sympathetic always exhibit a condi-tion of plasmolysis, attended with atrophy of the medullatednerve fibres "9»—changes which have a great resemblance t othose met with in Addison's disease. (Cf. also rl37, «7*.)

As previously mentioned, the glands participate in thegeneral atrophy, and this statement applies especially to t h eendocrine glands.JI37, 1I93 But the first of all the organs t obe involved in the atrophic process would seem to be t h edigestive glands—the salivary glands alone excepted. At t h every outset of the disease there is a falling-ofi in the amountof gastric juice, in the peptolytic power of the secretion, a n din its hj'drochloric-acid richness. In severe cases, there m a ybe no acid at all. This failure of secretion spreads by degreesto the whole digestive tract, so that in bad cases there iscomplete achylia.1^, 3**. Il87 The inevitable result is a g ravedisorder of digestion and absorption, this trouble beingaccentuated by the atrophy of the mucous membranes. ~85*3", 337 As a result, even in the early stages, the nitrogenousbalance tends towards the negative,316* 3*8 and before longbecomes definitely negative.Il87 Except for the interferencewith absorption, metabolism is said to nin a normal course 3 l 8 ;but this can only be true in very mild cases. Nistico 814claims that he has observed a falling-off in the tolerance for

PELLAGRA 303

carbohydrates, but his conception of the normal tolerance isso high (1*5 to 2-5 grammes of glucose per kilogramme ofbody-weight) that we are hardly entitled to speak of a realreduction in the carbohydrate tolerance.

The digestive disorders, and especially the lack of hydro-chloric acid in the stomach, cannot fail to react unfavourablyupon the nature of the intestinal flora, and at an early stagefermentations and putrefactions of all kinds set in. Owing tothe failure of the natural powers of resistance of the alimentarytract, every conceivable kind of affection of the stomach andbowel may ensue, ranging from simple heartburn to typhoid.Of course these disorders impair yet further the chances of thepatient's being satisfactorily nourished.-73. 285, 337,1066, 1176, 11*7

There is also grave disturbance in the balance of nutritionas regards inorganic salts. Even allowing for the fact thatabsorption is so much impaired, there is a negative balancein the case of all the inorganic nutrients as soon as the diseasebecomes acute.s85

The excretion of nitrogen, phosphorus, magnesium, cal-cium, and potassium in the urine is greatly diminished,x85385, 30* the reduction affecting the phosphates more than theurea, the alkalies more than the calcium, and the calciummore than the magnesium. When there is a sufficient supplyof sodium chloride, the excretion of sodium and of chlorinemay be normal or even increased. l84 The quantity of ammoniais always increased, both relatively and absolutely 8> l84, ia»6;and as a further sign of acidosis there is an increased excretionof acetone,8 and also of kreatinin in conjunction with well-marked kreatinuria.318 There is no uxobilin in the urine 3 I 4;but, owing to the great disturbance of intestinal digestion,there is an increased excretion of indican in the urine, oftenleading to marked indicanuria.442, Io66 Galmozzi records theremarkable observation that the sulphur in the urine in theform of ester compounds is diminished, a fact which perhapsdepends upon the invariable poverty of the pellagrogenic dietin sulphur

At the outset of the disease there is a moderate fall inblood-pressure (to 119 mm. of mercury) ; but the relaxationof the vascular tone rapidly increases pan passu with thegeneral loss of muscular tone, and when the disease is thoroughly

304 VITAMINS

established the blood-pressure ranges from 92 mm, to aslow as 78 mm.I l87

In the acute stage we find an excess of lymphocytes inthe blood, with neutral leucopenia and a faUing-off in thenumber of eosinophil cells,I44 phenomena met with in allessential anaemias. Reports are very variable as regards theserological conditions, and it will be best to defer the discussionof this matter until we come to consider the probable causesof the disease.

3. T H E PELLAGROGENIC D I E T .

The occurrence of pellagra was first recorded in connexionwith an ill-balanced diet consisting chiefly of maize. I t hasbeen supposed that the appearance of the disease in Europedates from the time when the cultivation of maize becamewidespread in Northern Italy, but there is no proof of thisassertion.312 For a long time it was believed that the patho-genic cause must be connected with maize, though it wasuncertain whether the influence was a specific property ofthe maize or was the outcome of a decomposition of the grain.The importance of maize as pathogenic agent was confirmedby the terrible spread of the illness in Rumania, where theannual toll of deaths from this cause became enormous, andwhere according to Urbeanu 8 the rural population lived almostexclusively on maize (for the amount of other food consumedper head in the course of a year would hardly exceed twokilogrammes.) Urbeanu was able to prove that an ill-balancedmaize diet induced pellagra-like diseases in fowls, and thisobservation was confirmed by Clementi.5*9 I t was foundthat other animals became pellagrous on a maize diet. As faras pigs are concerned, the effects of the inadequacy of maizein respect of the inorganic nutrients predominate in theclinical picture, so that pellagroid symptoms are not conspicu-ous 347; but dogs,4o6 guineapigs,^. 352* 3&> mice, and rats,become affected with pellagra on an ill-balanced maize diet.(Hoist,1?1 who experimented on guineapigs, regarded thedisease induced by a maize diet in these animals as poly-neuritic.)

The method of milling seems to have a certain influence.Suarez 489 reports that mice and pigeons, which on a maize

PELLAGRA 305

diet become pellagrous, are affected with polyneuritis if fedexclusively upon finely sifted maize flour or upon maizestarch (maizena), and tha t they can be cured by giving themyeast.

The effects of the maize are most pernicious when it isboiled. In the case of rabbits,»7 and in that of white mice,^*the supplementing of a diet of boiled maize with an abundanceof milk does not prevent the onset of the disease, whereasordinary mice can thrive on a diet of boiled maize and milk.Mice fed on wheaten rolls and milk were not found to displayany pellagrous symptoms. (Cf. Horbaczewski X3*.)

In the United States, however, pellagra was found tooccur, even in its gravest forms, in human beings whose diethad contained no maize a t all, or only a little. Most of thesepatients were able to command an adequate diet, bu t forone reason or another (generally they were neurasthenicswith a fixed idea that certain foods did not suit them) theylived upon an extremely restricted and therefore ill-balancedregimen. As typical of such defective regimens may bementioned the experimental diet prescribed by Goldbergerand Wheeler,IX57 whose subjects were prisoners voluntarilysubmitting to the experiment. The diet consisted of wheatand maize in the form of fine flour, maize starch, polishedrice, and small quantities of vegetables and fat. The subjectsof the experiment were put upon light work and received anallowance of " only " 2,500 to 3,500 calories daily, the dietcontaining 41 to 54 grammes of protein (mainly vegetable),91 to 134 grammes of fat, and 387 to 513 grammes of carbo-hydrate. In all the eleven subjects there occurred, in thecourse of 205 days, loss of weight and general debility.Abdominal pain and headache were frequent; in three therewas diarrhoea, and in five there was an increase of the knee-jerks. In the case of six of the subjects, typical cutaneousmanifestations appeared towards the close of the fifth month,but the site of these was in most cases anomalous. In twoonly did the skin eruption begin on the hands and the napeof the neck; in the other cases it began on the scrotum.

Chittenden and Underhill599 were able to induce typicalpellagra in dogs by feeding them on boiled bean flour, wheatenbiscuits, and linseed or cottonseed oil. (Cf. also fy1.)

20

3 o6 VITAMINS

4. VIEWS THAT HAVE HITHERTO PREVAILED CONCERNING

THE ETIOLOGY OF PELLAGRA.

a. Microorganisms as the Cause.

I t was, of course, believed at one time tha t infectionmust be the cause of epidemics of pellagra^8 , 878 fout sinceit was never possible to discover a specific microbe, the opinionwas abandoned. Harris 3z6 claimed to have induced pellagrain monkeys with morbid material from a case of pellagraafter the material had been passed through a Berkefeld filter;but subsequent observers, such as Lavinder, Francis, Grimm,and Lorenz,397 Siler, Garrison, and McNeal,4« and Bigland,J137were unable to secure any evidence of infection by the inocula-tion of the pellagrous matter or by its administration bymouth. Bass l83 believed himself to have proved the infectiouscharacter of the disease because he observed that fowlsacquired pellagra when fed upon maize that had been con-taminated with the faeces of pellagra pat ients ; but otherinvestigators were able to show tha t the alleged proof wasinvalid, seeing that a maize diet will induce pellagra in fowlsin the absence of any such contamination.

Babes reports favourable results from the treatment ofpellagra with arsenic, and considers that these successessupport his view that the disease is dependent upon aprotozoal infection.668* 669 Collodi JI7* I I 8 contests the infer-ence, for he holds that the observed improvement could readilybe explained as the outcome of the familiar stimulating andinvigorating action of arsenic. Alessandrini I a6 considers tha ta maize diet is merely a predisposing cause. He believesthat this diet gives rise to intestinal disorder which preparesthe ground for the invasion of the intestine by certain nematodeworms belonging to the family of the filaridae, the larvae ofwhich are to be found in the drinking water of regions wherepellagra is prevalent. This observation has not been confirmed,and the presence of filaridae in the intestine of pellagrouspatients was doubtless an intercurrent affection on all fourswith the accidental presence of different sorts of extraneousmicro-organisms.

The commission appointed by the United States Govern-ment to study the etiology of pellagra 3*8 was at first inclined

PELLAGRA 307

to regard the disease as a specific infection, and this viewseemed to be confirmed when it was found tha t in Spartanburg,South Carolina, a town where pellagra is endemic, there wasa notable decline in the number of cases after considerableattention had been paid to sanitary conditions.5I4 Accordingto Roberts,I007 however, this view has now been generallyabandoned, and pellagra is supposed to depend upon somesort of deficiency in the diet. Vallardi,l69 Patta, I 03 Car-letti,I79» l8° and more recently Boyd, l l87 are definitely opposedto the idea tha t pellagra is of an infective nature, and in especialthey reject the notion tha t a protozoon is the exciting cause.

The principal idea of the Italian school was tha t thecause of pellagra must be some sort of deterioration of themaize used for food. I n Germany, the view gained strengthfrom the s tatement of M. Otto tha t the growth on maize ofItalian cultures of Aspergillus fumigatus formed extremelytoxic substances, whereas the German stocks of the samefungus did not do so. The growth of Penicillium glaucumupon maize was also said to produce toxins, and in this caselikewise the Italian stocks of the mould were the most venomous.Tiraboschi,77 too, as a result of these researches and of hisown, considered t ha t such differences in the virulence of themoulds explained why pellagra appeared in certain < localitiesand not in others. Tizzoni,1^, *7<> again, considered tha tdamaged maize was the cause of pellagra, and claimed tha twhile he had been unable to produce pellagra b y feedingmonkeys on maize, he had succeeded in causing the diseasein these animals by the subcutaneous injection of cultures oforganisms isolated from the grain. The filtrate from suchcultures was said to produce precipitin reactions with theblood of pellagra patients ; bu t according to a later publicationof this authori ty ,^ 8 did so only after the bacteria in theculture had been broken up.

Camurri l 84 also assumes tha t moulds form a toxin inmaize. In the organism of healthy human beings the influ-ence of this toxin is supposed to be counteracted by anti-bodies, and the toxin can only take full effect in exhaustedor debilitated persons. * ^;A

According to Volpino, Mariani, Bordoni, and Alpago-Novella,l89» X9° both pellagra patients and heal thy persons

3o8 VITAMINS

react very little or not at all to the administration of aqueousextracts of damaged maize by mouth. In twelve out ofthirteen pellagra patients, however, the injection of I or 2 cc.of aqueous extract of damaged maize induced manifestationsof disorder of the central nervous system, also a rise oftemperature, and general, local, and cutaneous dis turbances;whereas in healthy persons the same injection induced nothingmore than a non-specific rise of temperature. For heal thyhuman beings and animals, the specific substance was almostnon-toxic ; it resisted heating to 115° C , and was soluble inwater. This " pellagrogenin" was precipitable by alcohol,thus contrasting with other toxins sometimes present indamaged maize, which are hardly soluble in water b u t arereadily soluble in alcohol and ether. But these investigatorswere unable either with the precipitin reaction, or b y themethod of deviation of the complement, or by passive anaphy-laxis, to demonstrate the existence of specific antibodies inthe reacting patients, and they therefore came to the conclusionthat the substance was not a true toxin but a poison of someother kind.

Carbon and Cazzamalli 3*7 claim that by growing Asper-gillus fumigatus, a Penicillium, Mucor racemosus, or Tricho-derma lignorum, on maize, they made the grain so toxic tha tordinary mice fed on it became affected with skin troublesor other signs of a pellagrous illness, whereas the originalundamaged maize did not engender any illness in t he mice.But this report conflicts with the well-established fact tha tundamaged maize certainly does cause pellagra in mice. Tothe toxins produced by the before-mentioned moulds, we cantherefore attribute at the most a predisposing influence.

b. The Effect of the colouring Matter of Maize, knownas Zeochin.

But before long a substance was discovered in maizewhich certainly seemed to be responsible for the causation ofthe skin affections forming part of the pellagra syndrome ;this was zeochin, the fluorescent colouring matter of yellowmaize. We have already learned that Horbaczewski wasable to produce pellagra in white mice by feeding t h e m onyellow maize and milk, whereas the same diet did not produce

PELLAGRA 309

the illness in ordinary mice. He supposed tha t the cause ofthe disease must be the alcohol-soluble colouring matter ,which, like all the fluorescent colouring matters , must, hethought, induce a special sensibility to direct sunlight, andindeed a hypersensibility to light in general. This view seemedto him to be confirmed by the observation t ha t the yellowmaize was no longer pathogenic after it had been decolourised,whereas white mice fed on their ordinary diet became pella-grous when this diet was supplemented with the colouringmatter , which was, however, innocuous to grey mice andrabbits. At most in ordinary mice, injections of the solutionof the colouring mat ter caused local skin trouble when theskin was exposed to the light. According to Suarez/89 thesubstance administered to rabbits in the same way has a similareffect upon these animals, but the feeding of i t to ordinarymice has no effect a t all. These statements were confirmedby Raub i t schek ,^ who also reported tha t zeochin causedskin trouble only in albinos, and only under the influence oflight on the skin. Ummes,245 in like manner, regarded thefluorescent colouring mat ter of yellow maize as the cause ofthe skin troubles. All the mice fed on maize soon succumbed,whether the maize was yellow or wh i t e ; bu t only when theyellow maize was given did the animal become affected witherythema. The other symptoms of pellagra were supposedto be due to an alcohol-soluble toxin present in maize.

Plausible as this explanation might seem, good reasonsfor doubting its validity were soon forthcoming. First ofall, it is a familiar fact tha t albinos in general and white micein particular are much weaker and less resistant than pig-mented animals of the same species. Ummes himself pointsout tha t white mice perish from starvation more quickly inthe light than in the dark. Furthermore, Rondoni l64 provedtha t white light is, in general, noxious to white mice ; alsotha t a maize diet causes pellagra in mice even in the dark,the animals pining, and suffering from a patchy loss of fur.Rondoni was unable to ascertain tha t the onset of the diseasewas hastened by the influence of light. The careful investiga-tions of Hirschfelder 2S° showed with considerable probabilitytha t the zeochin had nothing to do with the case ! THe ideahad, of course, been tha t the colouring mat te r was absorbed

3 i o VITAMINS

into the blood, and that its fluorescence made the blood moresensitive. Hirschfelder was able to show that although theblood-serum of pellagra patients was certainly fluorescent,the fluorescence was no greater than that of the normal serumof healthy persons, and that the t int was precisely the samein the healthy and in the diseased. Moreover, U r b e a n u 8

had proved that white maize, which contains no colouringmatter, is much more strongly pellagrogenic than yellowmaize.

I t is as well to point out that the morbific influence ofmaize seems to diminish with time. Bezzola80 noted t h a tmaize kept in store for a year had even, after boiling, n o illeffect on rats, whether the maize was good or damaged. I t isdoubtful if this investigator's experiments were carried on fora sufficiently long time, but Nitzescu 406 claims to have definitelyproved that new maize is more toxic to dogs than the s toredgrain.

c. The Effect of the Maize Toxin.

Like Ummes, and simultaneously, Rondoni *44 expressedthe opinion that the specific manifestations of pellagra weredue to a toxin in maize; but he left undecided the questionwhether this toxin was originally present in the maize or wasnot produced in it until the grain had been damaged byfermentation or putrefaction. He inclined to the latter view,finding that an aqueous extract made from damaged maizegave rise, even in healthy persons, to a slight reaction, t ak ingthe form of a moderate rise in temperature, of dizziness, andof malaise. Since, further, Rondoni discovered tha t thisreaction was stronger in pellagra patients than in hea l thypersons, it seemed to him that there could hardly be anydoubt as to its specificity. Nevertheless, though Volpino andhis collaborators lB9> 90 had maintained that the reaction wasviolent in pellagra patients (having the nature, they said, ofanaphylaxis), Rondoni was unable to confirm this observation.He therefore felt it impossible to maintain that the unmis-takable hypersensibility to the maize protein was really ofetiological importance.

Rondoni's conclusion was sustained by a subsequentresearch of Volpino's own.3&> Volpino found, indeed, t h a t90 % of pellagra patients were hypersensitive to the decom-

PELLAGRA 311

position products of maize protein, but he found also that20 % of perfectly healthy persons were no less hypersensitive.Such a reaction can hardly be regarded as specific. I t was,moreover, impossible by the injection of the so-called pella-grogenin to induce a passive anaphylaxis in guineapigs,though this would have been essential had the theory beensound. Lui and Baccelli*64 likewise reported tha t theprecipitin reaction was not to be trusted for an early diagnosis,seeing tha t it was not invariable, though it was usually presentin the early stages and in the acute exacerbations of thedisease, whether intestinal disorder was present or not. Butthe sera of perfectly healthy persons would also give a similarreaction at times.

Volpino reported, too, tha t his pellagrogenin did notinduce complement formation or a specific precipitin reactionin the serum of pellagra patients—although he believed tha tby repeated injections of a 10 % solution he ultimately pro-duced a certain degree of immunity, seeing tha t the animalsthus treated remained longer immune to the harmful conse-quences of a maize diet. When we recall, however, how muchthe period of incubation varies according to the internalcondition and the outward circumstances of pellagra patients,we shall not be inclined to regard this deduction as of muchvalue.

Other observers considered that the injuriousness of themaize depends upon the digestive disorders it evokes. Theysaid that Behring's extensive researches into the pathologyof tuberculosis had shown that when there was intestinaldisorder it was possible for undecomposed albumin to passdirectly into the circulation. In maize feeding, they supposedtha t the zein in particular was thus absorbed, and gave riseto hypersensitiveness. Especially they maintained tha t theblood of pellagra patients contained ferments which decom-posed zein, ferments whose existence had been proved by theresearches of Nitzescu.359,399, 406, 442 But Babes and Jonescu 394were able to show tha t Abderhalden's reaction to the zein-decomposing ferments is not invariable in the blood of pellagrapatients, and tha t it is fairly common in the blood of healthypersons if some transient gastro-intestinal disorder happensto facilitate the absorption of undecomposed zein,

3 i 2 VITAMINS

Gosio had asserted that the blood-serum of pellagrapatients contained a precipitin that acted on maize protein,but Rondoni J58 found that this reaction was not peculiar t opellagra patients. Like Abderhalden's defensive-fermentreaction, it is exhibited by the serum of normal persons, justas in the case of all the other vegetable extracts. Moreover,according to Carletti,l8° neither heteroprecipitms nor maize-precipitins are regularly found in the blood of pellagra patients.The occasional presence of such precipitins will certainly notexplain the problems of the etiology of pellagra. The bloodof the patients is sometimes hypertoxic for other persons,but it is very doubtful whether there can be much connexionbetween this and the maize diet.

Similar was the trend of the researches of Lucatello andCarletti,161 who found that antigens from the spleen andadrenals of pellagra patients sometimes induced comple-ment formation, but that none of the antigens gave a posi-tive reaction with the serum in all cases. The attempts ofVolpino and Bordoni 463 to induce active immunity were ablein guineapigs to secure no more than a " postponement" ofdeath, and in human beings to bring about " moderateimprovement." Volpino's claims that the injection of maizeextract in pellagra patients can induce an active immunity,and that in like manner a long continuance of a maize dietultimately leads to the acquirement of immunity againstmaize protein, are in such flagrant conflict with generallyobserved facts, that there must obviously have been someerror of experiment or interpretation on Volpino's part.

There is no doubt that zein can make its way throughthe diseased mucous membrance 359, 394,406, 742 • b u t it hasbeen rendered equally certain by Rondoni's experiments 348that in pellagra we have no ground for supposing that ahypersensibility to maize protein is the cause of the disease.Raubitschek *63 was also unable to discover any invariablechanges in the serological behaviour of the blood in pellagrapatients. We must, therefore, seek other causes for thedisease.

d. The Inadequacy of Maize Protein.

When the work of American investigators directed atten-tion to the importance of the biological value of protein, i ts

PELLAGRA 313

adequacy or inadequacy, in relation to health and disease,it was supposed tha t the riddle of pellagra had been solved.The work of Osborne and Mendel,2I7 and tha t of Funk,3*3had made it perfectly clear tha t zein is inadequate. Albertoniand Tullio 337 devoted special attention to the adequacy ofthe maize proteins in human diet. They came to the conclu-sion tha t maize is more slowly digested than other cereals,and is therefore more prone to give rise to putrefactive phenom-ena in the alimentary cana l ; that , generally speaking, maizeprotein is badly utilised ; and that if any accumulation ofnitrogen within the body should occur in children on a maizediet, this is not due to nitrogenous tissue growth bu t to theretention of nitrogenous waste products. They thereforecame to the conclusion tha t the injuriousness of maize dietmust depend upon the lack of certain nitrogenous tissuebuilders in the maize protein. Baglioni 393 likewise foundthat both zein and gliadin were inadequate, and t h a t anystorage of nitrogen tha t occurred when these were the mainproteins in the diet must be due to the retention of wasteproducts, seeing tha t despite this retention there was a steadyloss of weight. Rohmann,47^ and more recently Boyd,1066

regard the inadequacy of maize protein as the main cause ofpellagra, though Boyd is careful to explain tha t there mustbe other factors. Nitzescu 44* was led by the researches ofAlbertoni and Tullio and by those of Baglioni to modify hisviews in the same direction, coming to believe tha t pellagramust be part ly due to the inadequacy of zein and par t ly tothe absorption of unmodified maize protein. Raubitschek *63had come to the same conclusion at an earlier date. In likemanner, immediately after Osborne's researches were pub-lished, Centanni and Galassi293 accepted the idea tha t theinadequacy of maize protein must be the main cause ofpellagra; the photodynamically activating influence ofzeochin was a contributory bu t quite minor factor.

e. North American Experience.

Whilst a s tudy of Italian conditions had thus enforced theconviction t h a t the main cause of the symptoms of pellagramust be directly or indirectly connected with the food, tha tpellagra must be due to a maize diet, another tu rn was being

3 r 4 VITAMINS

given to the question by North American experience. I havealready mentioned that a commission appointed by theUnited States Government was at first inclined to believethat pellagra must be an infective disorder, but tha t th isopinion was subsequently abandoned. At the outset, Siler,Garrison, and McNeal 364 insisted that pellagra could not bedue solely to a maize diet, and indeed that there seemed tobe no necessary connexion between the disease and diet.This view was supported by the investigations of Chittendenand Underhill,559 who found that dogs quickly became affectedwith severe pellagra on a diet of boiled bean flour or peaflour, wheaten flour, biscuit, and cottonseed or linseed oil,although the nitrogenous balance was maintained. Whenthe diet was supplemented with meat, a cure ensued if thechange had been made early enough. In a critical s tudy ofthese researches, McCollum and Simmonds 69* pointed outthat the pathogenic diet had contained rather low-gradeproteins, had been defective in respect of A and B, and hadbeen most unsatisfactory as regards its inorganic ingredients.I t was a mistake, they said, to think only of proteins whenstudying the etiology of this disease; all the other constituentsof the diet must be taken into account. Elsewhere, they drewattention to the importance of the law of the minimum inthis connexion. I t was impossible, they said, when consideringthe pathogenic factors, to specify the minimal requirement ofany nutrient unless the investigator was aware of the biologicalvalue of all the other constituents of the diet.

We need not attach much importance to the statementof Jobling and Petersen,534 with regard to an epidemic ofpellagra in Nashville, Tennessee, that the diet of those affectedhad usually contained sufficient protein. They give no in-formation concerning the biological value of the protein orconcerning the other constituents of the diet. Far moreimportant is Funk's observation 303 tha t the endosperm ofthe maize grain, just like polished rice, consists mainly ofstarch and is extremely poor in other nutrients. Still, t h eobservation has not much bearing upon the problem we arenow considering, for in pellagrogenic diets the whole grain ofthe maize is commonly used, and we have learned above t h a tthe pure endosperm induces beriberi, not pellagra.

PELLAGRA 315

In Italy it was Bravetta110* who first observed theoccurrence of pellagra independently of a maize diet. Hefound that many cases of pellagra originated in Italianlunatic asylums, although the diet was abundant, varied, andcontained a sufficiency of proteins and vitamins. He noticed,however, that the patients who became affected with pellagrawere always weakly and cachectic; and we know tha t inasylums, just as among neurasthenics who are not underrestraint, an almost maniacal aversion to certain articles ofdiet is common. In such cases the diet actually consumedmay be extremely ill-balanced, although plenty of good foodis there for the taking. We may assume with considerableprobability that this accounts for the cases observed byBravetta.

/ . Specific Importance of Protein Deficiency.

The earlier views regarding the importance of protein haveoften tended to interfere with the at tainment of definiteknowledge of this matter . I t is doubtless owing to an exag-gerated valuation of protein that Bigland JI37 and Chick andHume IIoS have come to regard a deficiency of protein as themain cause of pellagra. Chick and Hume, giving a diet other-wise adequate, bu t in which the protein consisted of maizegluten, were unable to induce any pellagroid symptoms(erythema excepted) ; more especially, the experimentalanimals exhibited no sign of the typical nervous disorders.On the other hand, we have just learned that Bravet ta notedthe onset of pellagra in persons whose diet was apparentlywell provided with proteins. Goldberger, Wheeler, andSydenstricker,1101 studying the domestic economy in NorthAmerica in households where pellagra occurred and in thosewhere there was no pellagra, could not detect any definiterelationship between the incidence of the disease and eitherthe calorie content or the protein content of the diet.

The last-mentioned authorities noted, indeed, t h a t beforethe outbreak of the disease the diet of the pellagra patientshad been poor in products of animal origin, especially in milkproducts and in eggs. On the other hand the illness occurredindifferently upon diets in which maize, wheat, and ripe pulseswere respectively predominant. They therefore inferred tha t

316 VITAMINS

protein inadequacy must be one of the factors of pellagra.The before-mentioned experiments of Goldberger andWheeler IZ57 on criminals, and the investigations of Boyd Il87concerning the outbreak of pellagra among the Turkishprisoners of war at El Kantara, have the same bearing. Inthe El Kantara cases, rest and the supply of high-gradeprotein had excellent results.

g. Pellagra and Malnutritional Oedema.

Bigland IO37 is inclined to regard pellagra as due to malnutri-tion, and he assimilates the disease to malnutritional oedema.But Bigland's own observation,1^? and those of Enright,XI76upon the German prisoners of war in Egypt who becameaffected with pellagra, conflict with this theory, for both theseauthorities expressly declare that there was no malnutritionin the ordinary sense of the term. Conversely, Harris,1062

who studied the incidence of pellagra in Italy during the war,tells us that although the nutritive conditions were wretched,there was a definite decline in the frequency of this disease.

h. Vitamin Deficiency.

Ruhl,439 McCollum, Simmonds, and Parsons,^1 andBravetta,1103 agree in declaring that, despite the importantpar t played by the nervous symptoms, a lack of Funk'svitamin cannot be the cause of pellagra, seeing that thepathogenic diets have always contained an ample supply ofthis substance. The difference between vitamin deficiencyand pellagra is obvious in any case. In vitamin deficiency,the pareses are the outcome of degenerative changes in themuscles, or perhaps of degeneration in the distal ramificationsof the peripheral nerves. In pellagra, on the other hand,the degeneration affects the central nervous system.

i. Complettin Deficiency.

I t is, however, often asserted that a lack of other complettinsis the cause of pellagra. Nightingale^8 indeed, holds themistaken view that pellagra and zeism occur only as the out-come of a diet of hulled maize, and this leads him to supposethat a general complettin deficiency is the cause, McColluni,

PELLAGRA 317

Simmonds, and Parsons 69X correct this view by maintainingthat, whilst there is no lack of Funk's vitamin, a deficiencyof A or of B, or of both (in conjunction with other factors),must be of etiological importance. In another paper,878

indeed, the same authorities restrict the importance of com-plettin deficiency yet further, for they say that this deficiencymust act by lowering the resistance to infection, and thatthe main cause must be an infective agent. Goldberger,Wheeler, and Sydenstricker,1101* "57 on the other hand, considerthat complettin deficiency is a direct cause, although otherfactors must cooperate for the production of the typicalpellagra syndrome. A similar view was expressed byHopkins Io66 in the oft-quoted discussion of British medicalauthorities regarding the clinical importance of the complettins(London, 1920).

h. The Effect of inorganic Nutrients,

We have seen tha t almost all the constituents of our diethave in turn been looked upon as more or less directlyresponsible for the causation of pellagra. The only dieteticfactor still to be considered is that of the inorganic nutrients,and we find tha t some authorities insist upon their importancein this connexion* The first to pay attention to inorganicmetabolism in pellagra, and the only experimentalist whohas made systematic researches in that field, was the Rumanianphysician Urbeanu.8 He was, indeed, the first to approachthe problems of pellagra by the experimental r o u t e ; and inhis latest publication 5*5 he has been able to record a largenumber of protracted experiments on animals, extending insome cases to the fifth or sixth generation. Urbeanu wasstruck by the fact tha t maize is very poor in inorganic nutri-ents ; that there is a general lack of bases, but also a lack ofphosphorus; and tha t in this respect white maize is worseequipped than yellow maize. His experiments on dogs,guineapigs, fowls, pigeons, and human beings, invariablyshowed that white maize was far more dangerous than yellow.Although he does not deny tha t the lack of phosphorus mayhave some importance, he considers that the general deficiencyof bases must be the main cause of injury. Limitations wereimposed upon his researches by the lack of opportunity for

318 VITAMINS

elaborate analyses, and he was therefore chiefly concernedwith ascertaining the quantities of potassium provided inthe food and dealt with by the metabolic processes—startingfrom the fact that in vegetable nutrients (and, indeed, inanimal nutrients as well) potassium is greatly predominantamong the bases of the ash. He found, moreover, tha t thenutrients which have a curative influence, especially potatoesand green vegetables, are extremely rich in potassium. Inhis writings, therefore, he refers almost exclusively to potas-sium among the inorganic nutrients, although he says thatpotassium is to be taken as representative of the inorganicnutrients in general.

Feeding fowls on an exclusive maize diet, he found thatthe mere addition of calcium carbonate sufficed to preventthe appearance of pellagrous symptoms. Calcium phosphatewas less successful than calcium carbonate ; generally speaking,as far as white maize was concerned, calcium carbonate hadto be given as well as the phosphate. This is in conformitywith Nicolaidi's observation *85 that, even in healthy persons,on an ill-balanced maize diet the calcium and magnesiumbalance became negative, whereas the phosphorus balanceremained positive.

Although in one of their papers, Goldberger and Wheeler "57leave the question open whether an inadequate supply ofinorganic nutrients may not be responsible for the etiologyof pellagra, in another publication I I01 they definitely committhemselves to the opinion that this lack is of crucial importance.In conformity herewith, Centanni and Galassi293 found tha tguineapigs, which in general are extremely sensitive to theinjurious effect of maize feeding and of feeding with othergrains, throve upon a maize diet adequately supplementedwith green fodder.

We have already seen that all the cereals, including maize,have a low excess of bases and a poor calcium content. I twould be very remarkable should the law of the minimumfail to be valid where a diet of this grain is concerned.6^

//. The Effect of Silicic Acid.

Alessandrini and Scala,3«> 33&, 356 who also refer the causa-tion of pellagra to the peculiarities of inorganic metabolism,

PELLAGRA 319

have a favourite theory in this respect, which is doubtlessconnected with opinions that have been recorded concerningthe origin of goitre. They state tha t in regions wherepellagra is prevalent the drinking water is exceptionally richin colloidal silicic acid, and they say tha t they have proofthat this excess of silicic acid is the real cause of pellagra,maize feeding being no more than a predisposing cause. Theybelieve that the effect of the silicic acid is reinforced by theeffects of calcium chloride [!] and aluminium hydrate .Voegtlin,39& who has obviously been influenced by Alessandriniand Scala, contends that the aluminium found in many vege-tables is one of the factors of the disease. Recently, however,Breest 127I has definitely established that whereas the ingestionof soluble silicic acid, and still more the ingestion of solublesilicates, may lead to a certain accumulation of silicic acidin the animal organism, colloidal silicic acid is not absorbed,and the animals ingesting it remain perfectly healthy if theirdiet is otherwise satisfactory. Seeing tha t Alessandrini andScala found that the troubles they supposed to be due tosilicic acid were perfectly relieved by alkalies or by calciumcarbonate, we must suppose that the lesions met with intheir researches were local or general effects solely due to theinfluence of acidity. What they tell us of the morbid anatomyof the affections confirms this theory.

m. Mental Influences.

Finally, it is necessary to point out tha t in pellagra, asin all other nutritive disorders, the onset of the disease maybe greatly influenced by psychical causes.I007 Homesickness,anxiety, sorrow, anything tha t causes mental depression, maynotably accelerate the appearance of pellagra.

n. Complications.

The association of pellagra and scurvy is fairly common,1?*but an association of pellagra and beriberi has not hithertobeen noticed. I t must be remembered tha t the period ofincubation of beriberi is brief and tha t the onset of the illnessis acute, whereas typical pellagra has an incubation periodlasting several years

320 VITAMINS

5. SUMMARY.

Anyone who wishes to ascertain the cause of a nutritivedisorder, must be acquainted with the factors that can effecta cure. A comparison of the remedial diet with the pathogenicdiet affords the quickest way of learning what constituentsof the latter, whether by excess or by defect, must be heldaccountable for the various symptoms of the disease. Thefirst thing we have to note is that in pellagra, as in othernutritive disorders, the simple addition of butter to thefaulty diet tends to make matters worse rather than better.1^8

Enright "7* reports that a diet of bread, meat, and eggs isbeneficial; but it cannot be said that his results were particu-larly encouraging, although as he was dealing with prisonersof war most of his cases were of recent origin. Of the 65cases under his care, only 46-1 % were cured, and 33-8 %improved (with marked increase in weight) ; but in a freshlydeveloped nutritive disorder one might have expected muchbetter results.

Boyd,Il87 whose experience was also made in Egypt, butamong Turkish prisoners of war, considers that , in additionto rest, the supply of a high-grade protein is the most importantremedial measure. The provision of protein of high biologicalvalue and the simultaneous suspension of work, led to asudden fall in the number of cases reported.

As soon as the inadequacy of the protein in the pathogenicdiet had been recognised, as a matter of course the improve-ment of the quality of the protein was seen to be . t he firstessential for the remedial diet. McCollum, Simmonds, andParsons 878 report that milk and milk products form the bestsupplements to a faulty diet. Roberts,I007 in like manner,demands that the diet shall contain lean meat, eggs, butter ,and milk. Apart from Urbeanu, Roberts seems to have beenthe only authority to stress the great value, in addition, ofvegetables rich in bases (this implying the avoidance of ripepulses!). He informs us that in the United States, whereduring the last twenty years there have been about half amillion cases of pellagra with a mortality of 10 %, the numberand the severity of the attacks has notably declined sincedefective nutrition has been recognised to be the main cause

PELLAGRA 321

of the disease. In former days, the largest proportion of thedeaths registered as due to pellagra were in cases of typhuspellagrosus; this acute form of the disease is now r a r e ; onthe other hand there has been a notable increase in the propor-tion of slight cases. These lesser cases are apt to be over-looked, especially when there is no dermatitis (" pellagrasine pellagra").

Nevertheless it must not be forgotten that the inadequacyof the protein in the pathogenic diet can by no means accountfor all the features of the pellagra syndrome. Innumerableexperiments upon feeding with an inadequate protein havebeen made, especially by the American school. Some of thesehave been carried out for several generations of the experi-mental animals, and as long as the diet has been in otherrespects adequate, no disease resembling pellagra has everbeen induced. The results of protein inadequacy are : arrestof weight or loss of weight, refusal of food, cachexia, and deathfrom cardiac asthenia—unless, in the debilitated animal,some complication arises to hasten the end. Although thesymptoms named are well marked in pellagra, there are otherwell-marked and typical symptoms in that disease whichmust be due to a different cause. The frequency of pellagrawithout dermatitis in American experience makes it probable,seeing that a maize diet certainly plays less par t in causingthe disease in the United States than in Italy, tha t zeochinmust be the chief factor of the skin trouble. But the derma-titis (which, moreover, may be aggravated, if not directlyexcited, by an excess of common salt and of acids in the diet)cannot be regarded as pathognomonic of pellagra. The mostcharacteristic symptoms are the nervous disorders, which areobviously due to changes in the central nervous system. I tmust be admitted tha t we cannot as yet indicate any factorwhich has a peculiar selective influence such as is certainlyexercised in pellagra upon the spinal cord and the greatnerve trunks. Here, then, is an additional point tha t requireselucidation.

Perhaps the work of XJrbeanu will prove of enormousimportance in this connexion. My own innumerable observa-tions of sick persons during the last twelve years haveconvinced me tha t a lack of bases in the diet impairs the

21

322 VITAMINS

efficiency of the nervous system, the disorder being especiallymanifested in the form of neurasthenia and of migraine.These observations are in conformity with those of Hirschstein,who claimed moreover that in a particular case of migrainehe obtained chemical proof that a deficiency of organicallycombined sulphur was a contributory cause. This lack oforganically combined sulphur is likewise characteristic of thepellagrogenic diet, and it is certainly remarkable that proteinsrich in cystin should be found especially valuable as ingredientsof the remedial diet.

Perhaps a lack of bases in general, and a deficiency ofcalcium and potassium in particular, in conjunction with anexcess of acids and a lack of organically combined sulphur,might in course of time induce the nerve degenerations charac-teristic of pellagra, especially if the before-mentioned faultsin the diet were supplemented by the inadequacy of theprotein it contained, by deficiency in respect of A, B, and D,and may be at times also by deficiency in respect of C.

CHAPTER TEN

CONCLUSION

As we have seen in the foregoing chapters, the data of themodern doctrine of nutrition are still dispersed in thousandsof brief essays and reports. The mere collection of the writingsmost essential to the understanding of the subject is a formid-able task. A further difficulty in securing a grasp of thematerial arises because in many cases an important factnever finds direct expression. Sometimes, being taken bythe specialist as a mat ter of course, it is ignored and has tobe read between the lines. Other facts, again, like tha t ofthe importance of an excess of bases in the diet, have escapedthe notice even of the experts, and have to be discovered bya comparison of the details recorded in numerous investiga-tions. We have no right, therefore, to reproach laymen(and as far as this subject is concerned, medical practitionersand the students of the chemistry of nutrients must be includedamong the laity) because their views concerning the moderntheory of nutrition and the results of the experimental studyof the physiology of nutrition are so confused and obscure—if, indeed, they have any opinions at all upon thesetopics.

But even the expert finds it extremely difficult to takea survey of the whole field, and the difficulty is especiallyconspicuous in connexion with the planning and carrying outof experiments. Thanks to the persistent endeavours of theAmerican school, even here there has been a certain clarifica-tion during the last year, so that we may look forward to agreater uniformity in future results. Systematised methodshave beep, formulated for the study of the various complettins,and have shown themselves to be of practical use ; b u t their

.323]

324 VITAMINS

application demands critical faculty, judgment, a knowledgeof the literature, and wide practical experience.

i . DIFFICULTIES ATTENDANT ON MODERN EXPERIMENTS

CONCERNING NUTRITION.

What applies to the more refined methods of chemicalinvestigation, applies also to the experimental study ofnutrition. An investigator may have given the most detailedaccounts of his procedures, and one who endeavours to followin his footsteps may be most scrupulous in the attempt toobserve these prescriptions, and still the result may be unsatis-factory. Success cannot be guaranteed until methodologicaldetails have become automatic from long practice. Even themost proficient analyst will not have satisfactory resultson the first occasion that he attempts to apply a complicatedmethod. He has to make a number of trial experimentssimply to secure familiarity with the technique.

In biochemical experiments upon nutrition the difficultiesare, however, enormously greater than in ordinary chemicalinvestigations, where the substance under examination issecurely confined within the walls of a glass vessel. Thematerial studied in the physiology of nutrition is the livingorganism with its infinitely manifold individual variations,which may be decisively modified by quite inconspicuouscircumstances.

I have repeatedly insisted that in such studies an experi-ment lasting several months may still be too short to givetrustworthy results, and that the whole lifetime of the animalunder examination may not suffice. In such cases our onlyresource is to continue the experiment for several generations.If after five or six generations the development of the animalsis still perfectly normal, we may then assume that the condi-tions of our trial experiments are in sufficiently close conformitywith the conditions under which the animals in questionlive in a state of nature. Not until then can we safelyproceed to ascertain the effect of withdrawing one of theconstituents of the diet or of increasing the quantity ofanother.

But we must be extremely critical in our interpretation ofthe experiments when this stage has been reached. We are

CONCLUSION 325

not dealing with chemical constants, bu t with living beings;and although to our eyes they may seem as much alike astwo prints from the same negative, they are really character-ised by marked individual variations. If the number of theanimals subjected to experiment be small, there is always arisk that the whole research may be invalidated by thesechance variations. Not until the number of the experimentalanimals is considerable, can the experimenter be certain ofavoiding such errors.

In this book there has been frequent occasion to mentionthe accidents that can interfere with experimental results.Let me remind the reader of the experiment on vitamin inwhich jHhe anijnais ate fh^ir nwn_£a<ar <5 Thi^

326 VITAMINS

apparatus designed by Robertson and Ray for investigationson mice, it will still be necessary, in these new surroundings,to study the undisturbed life-history of a great number ofanimals before proceeding to the actual experiment. Thepossibility of local variations must always be taken intoaccount.

2. T H E COMPLETTIN CONTENT OF FOODSTUFFS.

Anyone making experiments as to the effect of complettins,must, of course, know where they are present, and approxi-mately how much of them the various nutrients contain. Butthis question does not concern the laboratory experimentalistalone; it is perhaps even more important to anyone who hasto prescribe diets for others. I am, in fact, besieged withqueries on this subject, not only by doctors, but also byhousewives and by the heads of institutions. I can hardlyemphasise the importance of the matter better than by quotinga passage from Sherman and Smith's latest work.J554 I shouldmention that until recently Sherman was one of the mostzealous advocates of the protein-calorie doctrine!

" If we compare the human organism to an internalcombustion engine (the traditional simile of the steam engineis inapt), the organic nutrients constitute the fuel, theprotein and part of the inorganic nutrients form the materialsout of which the engine is made, the rest of the inorganicnutrients represent the lubricating oil, and the complettinsplay the part of the spark. . . . All these substances areessential to the working of the machine. . . . In accordancewith the law of the minimum, any one of them can functionas the determining factor of the whole process. . . . Inscientific experiments we may devote special attention to thesupply of protein or to the provision of a sufficiency of calories.On the other hand, when we are practically planning a dietor considering the nutritive requirements of a family, we shalldo better to make it our first aim to ensure the supply of asufficiency of those nutrients which are known to us to bepreeminent as conveyors of the necessary inorganic salts andthe complettins. Not until then need we conbern ourselveswith the possibility that it may be necessary to supplementthe diet ill respect of protein or of energy by a further supply

CONCLUSION 327

of some suitable nutrient. Consequently, the person respon-sible for the diet must, above all, see to it that there shall bea sufficiency of milk, vegetables, and fruit, thereafter, cerealsmeat, fats, and sweetstuffs may be added according to thetaste, the financial resources, and the digestive powers ofthe individual, and according to his needs in respect of energy.. . . Here is a good empirical rule in reckoning dieteticalrequirements. Spend at least as much upon vegetables andfruit, and at least as much upon milk, as you spend uponmeat, fish, cereals, and sweetstuffs! " [Retranslated fromthe German.]

In preparing the following table I have made use of allthe data known to me in the literature of the subject. Theemployment of the very latest results of research has ledto considerable differences between my table and similarones that have previously been published, but I think thatmy own is the most trustworthy issued to date. I describethe content of a complettin as " enough " when the quanti tysuffices, not merely to cure, but also to prevent a deficiencydisease. When the content is so considerable tha t even verysmall quantities of the particular nutrient are effective, thiscontent is described as " much." Amounts tha t are con-siderable, though not adequate, are denoted by the term" lit t le/ ' Insignificant amounts are described as " trace." Azero is used to indicate tha t no complettin can be detected.A query denotes tha t definite information is lacking (p. 328).

3. NUTRITION IN COMPLETTIN EXPERIMENTS.

Numerous standard diets have been tabulated for use inthe study of the various complettins. Seeing tha t again andagain new dietetic factors requiring special attention havecome to light, all the older prescriptions can unhesitatinglybe * discarded as obsolete. To-day, for researches concerningthe biological value of the different prtiteins, the recommendationsof B. Sure ll6s> x*6* are those most worthy of consideration.For rats, he used an experimental diet consisting of dextrinisedmaize starch, Osborne's latest mixture of salts, clarifiedbutter fat, and as conveyer of the water-soluble complettinsan alcoholic extract of defatted wheat germs, while maceratedagar was added as roughage. By present lights, a few Improve-

328 VITAMINS

FLESH-MEAT, FISH, EGGS.

Muscular Tissue (freshmeat)

Tinned MeatMeat, frozen (not long

in store)Meat, frozen (long in

store)Meat, salt (not long

in store)Meat, salt (long in

store)Brain ..Heart ..KidneyLiver ..SpleenMeat Extract.Fish, leanFish, fatFish, roeEggs (fowl's) .

m a

Egg (white of)Egg yolk of)

Vitamins

littletrace

Httle

trace

Httle

a traceenoughHttleenoughenoughHttletraceHttleHttleenoughHttletraceHttle

D

ptrace

Httle

?

p

p?p?p?pp??Pp?

A

littletrace

Httle

trace

Httle

traceHttlemuchenoughmuchHttletracetraceHttleHttleenoughtracemuch

B

littletrace

Httle

trace

little

traceenoughHttleenoughenoughHttlelittleHttleHttleenough ?littletraceenough

C

littletrace

Httle ?

trace

Httle

traceHttle?Httle?Httle ?Httle?

o?trace

o?little ?Httle?trace ?tracetrace?

Beans, haricot (freshly-dried)

Beans, haricot (old) ..Beans, haricot (ger-

minated)French beans (fresh)..Beans, soyBeans, katjang-idjo ..Peas (ripe)Peas (young green) ..Peas (germinated) ..

PULSES.

muchtrace

traceenoughmuchmuchenoughenough

much?

?enoughmuchmuchenoughenough

littletrace ?

trace ?enoughtrace ?

penoughenough

enoughtrace

traceenoughmuch ?enough ?enoughenoughmuch ?

trace ?trace ?

enoughenoughtrace

?little?enoughenough

CEREALS, SEEDS, FLOURS, BREAD.Rye (whole grain)Rye (fine flour)Rye (bread, whole-

meal)Wheat (whole grain)..WEeat (endosperm) ..Wheat (germ)Wheat (bran)Wheat (wholemeal) ..Wheat (bread, white,

with water)Wheat (bread, white,

with milk)Wheat (bread, whole-

meal, with water) ..

enoughtrace

littleenoughtracemuchmuchenough

little

little

enough.

enough?

?enough

?muchmuchenough

little

little

enbugh

littletrace

littlelittletracelittlelittletrace

?

little

little

enoughtrace

littleenoughtracemuchenoughenough

little

little

little

little ?trace

?tracetracetracetracetrace

trace

?

?

CONCLUSION

CEREALS, SEEDS, FLOURS, BREAD—continued.

329

Wheat (bread, whole-meal, with milk) . .

Barley (whole grain)..Barley (groats)Oats (rolled) . .Malt (green)MilletRice (unpolished)Rice (polished)Maize (yellow, whole

grain)Maize (white, whole

grain)Maize (fine flour, maiz-

ena)Cotton seedsCotton seeds (fine

meal)LinseedHemp seeds

Earth-nuts . .Hazel nutsHickory nutsChestnuts (Spanish)CocoanutCocoanut (cake)Almonds (sweet)Para nutsPine kernels . .Walnuts

ApplesOrangesOranges (juice)BananasPearsCocumGrape-fruit . .Raspberries . .LimesMangoesMulberriesMulberries (dwarf)PlumsTomatoesTomatoes (boiled)GrapesGrape juice . .Lemons (ripe)Lemons (green)

Vitamins

enoughenoughenoughenoughenough ?enoughmuch

trace

enough

enoughtraceenough

enough??

enoughenough

?enough ?

enough

enoughp??

NUTS.

enouglittlelittlelittlelittlelittlelittle

trace

little

tracetracelittle

tracelittlelittle

FRUITS.

enough ?enoughlittlelittleenough ?enough ?enoughtrace

enough

enough ?

traceenough

trace

enoughenoughenoughlittleenoughmuch.littleenoughlittleenough

enoughenoughenough

?enoughmuch

penough

?enough

littletrace ?trace?trace ?littletracelittletracelittletrace?

enoughenoughenoughenoughenoughmuchlittleenoughlittlelittle

Httleenoughenoughenoughlittle

renough

Httle?r?

Httlemuchmuchenoughlittleenoughmuch

?enoughenoughenough

?r

enough???r??

muchmuchenough

?enoughmuch

littlelittletracelittletrace ?

?r>r

trace ??r??

muchmuch

?Httle ?littlemuch

littlemuchenoughenoughlittle

tenough

renough

•\i?

Httlemuchmuchenoughlittleenoughmuch

ptracetracetraceenough

o ?tracetrace

trace

trace

traceenough

trace

trace ?

trace ?trace ?

littlemuchmuchmuchtrace ?HttleenoughmuchHttlelittlelittlemuch

?muchmuchenoughenoughmuchmuch &

330FRUITS—continued.

VITAMINS

Lemons (juice of com-merce)

Tamarinds (dried)

Vitamins

pp

D

p

A

p

B

p

C

enoughlittle

ROOTS AND TUBERS.Sweet potatoesPotatoes (raw)Potatoes (boiled

one hour) . .Potatoes (dried)Carrots (raw)Carrots (boiled)Carrots (juice)ParsnipsRadishesBeetrootsTurnipsKohlrabiMangel-wurzelsSwedes

for

littleenough

enoughenoughenoughlittlemuchenoughlittlelittleenoughenoughenoughenough

littleenough

enoughenoughenoughlittlemuchenough

?p

enoughenoughenoughenough

enoughlittle

littlelittleenoughenoughenoughlittletrace ?

?littleenoughenoughtrace ?

littleenough

enoughenough ?enoughlittlemuchenoughlittlelittleenoughenoughenoughenough

GREEN VEGETABLES, LEAVES, ETC.ArtichokesLucerneGreen leaves ..CauliflowerDasheenEgg-plantGrassGreen cabbageCucumberHayClover (fresh)..LettuceCressesTimothy grassDandelion leavesRhubarb (stalk)Pickled cabbage (Sauer-

kraut)CelerySpinach (raw)Spinach (boiled)Spinach (dried)Pumpkin (squash) ..White cabbage (raw) .White cabbage (boiled)White cabbage (dried)Onions

littlemuchmuchenoughlittleenoughenoughenoughlittleenoughmuchenough

enoughenough

pmuchenoughenoughmuchenoughenoughenough

pmuchmuchenough

?enoughenoughenough

??

muchenough

enoughenough

pmuchenoughenoughmuchenoughenoughenough

enoughmuchmuchlittletrace

pmuchmuch

penoughmuchenough

muchmuch

\

muchmuchmuchenoughenoughenoughlittletrace

littlemuchenoughenoughlittleenoughmuchmuchlittleenoughmuchenough

muchenough

littlemuchenoughenoughmuchenoughenoughenough

MILK AND MILK PRODUCTSHuman milk ..Cow's milk ..

enoughenough

enoughetaough

much | enoughmuch enough

tracemuchenoughlittleenoughlittlemuch

trace ?p

muchmuchenoughmuch

pmuchenoughlittlelittletraceenoughmuchmuchtracemuchmuchlittleenoughenoughlittle

pmuchenoughtrace

muchenoughlittleenough

enoughvariable

CONCLUSION

MILK AND MILK PRODUCTS—continued.331

Cow's milk (scaldedonly)

Cow's milk (pasteur-ised)

Cow's milk (con-densed)

Cow's milk (driedslowly)

Cow's milk (dried in-stantaneously)

Cow's milk (skim-) . .Cow's milk (butter-) ..ButterCreamCheese (skim-milk) . .Cheese (full-milk) . .

Cottonseed oilEggfatEarth-nut oilFish oilCocoanut oil . .Codliver oil . .Linseed oilMaize oilAlmond oil . .Margarine (vegetable).Margarine (animal) . .Nut oilOleomargarine (olein).Olive oilOrange-peel oilPalm oilHorse fatBeef fatMutton fat . .Pig fat (kidney fat) . .Pig fat (lard)SuetStearinWhale oil

YeastYeast (dried) ..Yeast (extract)

Vitamins

enough

little

enough ?

trace

enoughenoughenoughtraceenoughtracetrace

enough

little

enough ?

7

enoughenoughenough

enough

much

much

much,

much

much.littlelittlemuchmuchlittleenough

YEAST PRODUCTS.

enough

little

enough ?

trace

enoughenoughenoughtraceenough

?

SUGARS AND STARCHES.

FATS?00000?00000000

trace ?00000000

trace ?

AND OILS.?00000?00000000

trace ?00000000?

littlemuchtracemuchtracemuchtracelittletracetracelittletracelittletraceenoughlittlelittlelittlelittleenoughtracelittletraceenough

?00000?00000000

trace ?00000000

trace ?

muchenoughmuch

muchenoughmuch

muchtracetrace

traceenoughmuch

variable

trace

trace

trace

variablevariablevariabletrace ?variable

ooooooooooooo

trace ?ooooooooo

tracetracetrace

Sugar (refined)Honey..Honey (artificial)Starch

0little

0trace

00?00?

0000

0000?

0000

332 VITAMINS

ments might be suggested. Potato starch would be preferableto maize starch, for the latter contains traces of colouringmatter which might prove injurious (especially to white miceand white rats). The salt mixture could be bettered byincreasing the dose of calcium carbonate to about 170 grammes;the small quantity of manganese sulphate should be replacedby 10 grammes of manganese ci t rate; the magnesia shouldbe increased to 20 grammes; the phosphoric acid should bereduced to 60 grammes; and, finally, 5 grammes of crystallinesodium silicate should be added to the mixture. I t stillremains to be decided whether this mixture will prove adequatefor several successive generations of the experimental animals.(See next paragraph.) The use of wheat germs instead of theyeast extract that has hitherto been customary is not adesirable change, for we have seen that wheat germs arecomparatively poor in complettins. Better than either wouldbe an extract of young clover not yet flowering or of youngspinach, precipitated with alcohol to get rid of the proteinsand then heated for a short time to 60 ° C. Of course allthese extracts contain ammo-acids, which must on no accountbe left out of the reckoning.

In experiments on the inorganic nutrients, the protein ofthe diet should be supplied in the form of carefully purifiedcasein and lactalbumin ; the other constituents of the foodshould be pure potato starch, macerated agar, clarified meltedbutter fat, and the improved salt mixture just described.Special series of experiments should immediately be under-taken to ascertain whether the experimental animals canreally thrive for a number of generations without a triflingaddition of copper and zinc to the diet. In experiments upon,the various forms of combination of phosphoric acid and ofsulphur, it must not be forgotten that the proteins and thebutter contain these substances, and that the amount ofthem in the macerated agar is by no means negligible. Theexperimenter must also bear in mind that the most sedulouslypurified nutrients always contain quantities of ash wMch mayin certain circumstances be of decisive importance. Let meremind the reader of what was said in the third chapter anentthe phosphorus content of edestin, and also of my ownexperience that purified fats invariably contain organically

CONCLUSION 333

combined sulphur. Hence it is perhaps better to use achemically pure filter paper as roughage.

In experiments upon the action of the real vitamins(Funk's), difficulties arise which have been especially stressedby Sinionnet.^01 Hitherto these experiments have usuallybeen made with nutrients which in other respects were extremelyinadequate, and it is doubtless for this reason that the morbidanatomy of beriberi and experimental polyneuritis is sodiversified. Simonnet recommends the following experi-mental diet : meat, thoroughly boiled and pressed, thenextracted twice with boiling alcohol and once with ether,I I grammes; Osborne's salt mixture, 4 grammes; agarpowder, 5 grammes; earth-nut oil, 5 grammes; but ter fat,10 grammes ; quantitative filter paper, 5 grammes ; potatostarch, 60 grammes. After mixing with 80 % of distilledwater, the mixture is given to pigeons by cramming, the dailyallowance amounting to half the weight of the birds. BothB and C are lacking in this mixture as well as v i tamin; butthe lack of B and C is of comparatively little importance,for it has not time to make itself felt owing to the rapid develop-ment of the consequences of vitamin deficiency. There is,however, one grave defect in Simonnet's recommendations;they take no account of the difference in the respective effectsof vitamins and the water-soluble antineuritic D. Theproblem of the origin of the various forms of polyneuritiscannot be solved without the recognition of this difference.We have learned tha t the two classes of substances unques-tionably make their lack felt in different parts of the organism.As yet we have no trustworthy method by which Funk'svitamin and water-soluble D can be wholly separated eachfrom the other, and in this department of the research thediscovery of such a method must be our immediate task.Next comes an additional point to be considered. I t hashitherto been assumed that the lack of B in these experi-ments is of no moment, for the incubation period of polyneu-ritis is so short tha t B deficiency cannot make itself felt. I tis nevertheless possible tha t even in so brief a period the lackof B may take effect, especially upon the glands. Moreover,we have already notedfthat C deficiency is probably the causeof the trifling haemorrhages sometimes met with in cases of

334 VITAMINS

polyneuritis. We must, therefore, endeavour to discoverways and means of freeing B and C from vitamins and thewater-soluble antineuritic D, so that a sufficiency of B andC may be added to the experimental diet.

When studying the conditions of growth, the experimenterwill naturally regulate the experimental diet with an eye tothe special problem under examination, but he must takethe utmost care that in other respects the diet shall beadequate. A study of the fat-soluble complettin is a fairlyeasy matter, for this complettin is readily destroyed byoxidising agents. But it must not be forgotten tha t thecomplettin C, whose presence in the diet is absolutely indis-pensable in these cases, is likewise sensitive to oxidisingagents, and may therefore be destroyed by the methods usedfor the removal of A. Similar and more formidable difficultiesarise in the study of the effects of B, for the means employedto free the diet from B are apt to destroy D and C as well.There is still a good deal to be cleared up in connexion withsuch matters, and much further work will be requisite beforeit will be possible to provide a throughly satisfactory experi-mental diet suitable for each particular type of investigation.As an example of the technique of these investigations, Imay refer to Osborne and Mendel's latest publication,X33r

with the remark, however, that the diet there mentioned isdesigned solely with regard to the fat requirements of theexperimental animals, and contains a source of fallacy eventhere. Dried, pulverised meat cannot be completely defattedby extraction with alcohol and ether, and in the prescribeddiet the meat powder of the daily ration will still containabout o*4 grammes of fat.

Byfield, Daniels, and Loughlin "53 tabulate an excellentfundamental diet which they suppose to be satisfactory evenin respect of the absence of the water-soluble complettins.But they were investigating the problem as to whether vitaminand B are identical, and obviously the diet they recommendis quite unsuitable for the purposes of this investigation,seeing that the deficiencies of vitamin, B, C, and D reinforceone another. Moreover, in experiments on growth-factors,casein should not be the only source of protein,f seeing thatthis protein is not wholly adequate for the growing organism.

CONCLUSION 335

We must either give an approximately equal quantity oflactalbumin in addition, or else, following Osborne andMendel's example, use meat protein purified as thoroughlyas possible.

An experimental diet for the study of the effects ofB-containing extracts is not difficult to arrange. I t shouldconsist of meat tha t has been pressed and thoroughly boiledand subsequently extracted with alcohol and ether, starchsimilarly extracted, salt mixture, and filter paper. Theallowance of fat must be kept for several hours a t a tempera-ture ranging from 1200 to 1300 C. with air passing throughit all the time, to free it from A. As conveyer of the water-soluble complettins, a vegetable extract will be used, freedfrom A by extraction with alcohol and ether. The smallquantities of vitamin or of water-soluble complettins whichmay pass off in solution when the inspissated extract is beingextracted in vacuo are negligible provided a sufficient amountof the extract be added to the diet.

For the study of the effect of the antiscorbutic complettin0, it is likewise comparatively easy to arrange a diet thatshall be adequate in other respects. This diet will consistof pure proteins, dextrinised starch, a fat (preferably butterfat as conveyor of A), filter paper, and salts. As conveyersof the other water-soluble complettins, we shall use anexpressed vegetable juice, spinach juice for instance, in whichthe C has been destroyed by evaporation to dryness in vacuoat a temperature ranging from 6o° to 700 C.

The foregoing indications as to experimental diets haveno claim to completeness. They are merely intended <o showthat, despite the elaborately developed technique, the diffi-culties to be reckoned with in these experiments are stillextensive; and to show, further, tha t all the problems arestill in a state of flux. A great deal more work will have tobe done before we shall possess an unexceptionable techniqueeven for one branch of these investigations. I t is, therefore,rather remarkable tha t Aron and Gralka I38 6 should declareit to be the duty of investigators henceforward, not only todetermine (as heretofore) the amount of protein, fat, carbo-hydrates, and inorganic salts the nutrients contain, but toascertain also by experiments on animals the biological value

336 VITAMINS

of these nutrients as regards protein, fat, and complettins.Aron seems to have no idea of the amount of work that isalready imposed upon those who are studying" the biocliemistryof nutrition, and he fails to realise the scantiness of theirresources. For such investigations as he recommends itwould be necessary to have a regular zoological garden witha highly trained staff. No private investigators have anythingof this sort at their disposal, nor as yet can official researchlaboratories command anything like it. One who readsAron and Gralka's paper cannot but feel ironical when henotes that even so distinguished an investigator as Aronhimself is obviously tinaco[iiainted with the most importantresearches of the last two years. In especial it must bementioned that the salt mixture recommended by Aron isquite inadequate. [Furthermore, he suggests plasnion as asource of protein, but in long-continued experiments thisprotein proves inadequate.

4. THE IMMEDIATE PROBLEMS OF COMPLETTIN- RESEARCH.

What are the immediate tasks of complettin research ?They are as follows : further study of the biological value ofthe various proteins used as nutrients; an examination asto how far there is a vital need for certain inorganic sub-stances universally present in natural food, h u t present onlyin very small quantities ; the differentiation of Funk 's vitaminsfrom the antineuritic complettin T>, and from the growth-factor B ; a study of the function of the fat-soluble complettinA in the organism of growing animals and adults respectively ;finally, the isolation of the complettins in a pure state. Fur-ther, it will be eminently desirable, in all these researches, t oseek the aid of experts in pathological anatomy, so tha t wemay ascertain the precise effect upon the organs and tissuesresulting from a lack of the various complettins. This know-ledge would be of the greatest value to therapeutics. Finally,I must insist once more that the methods hitherto employedfor the analytical determination of the inorganic constituentsof the diet, whether employed by biologists, medical practition-ers, or biochemists, have been inadequate and misleading.The Experimental Stations Office in Washington, U.S.A., hasrecently endorsed this criticism. The utmost accuracy isessential in such investigations.

CONCLUSION 337

5. T H E N E E D FOR STATE A I D IN EXPERIMENTS ON

NUTRITION.

It is obvious that these problems can only be studied withsuccess in great institutes, with the aid of large laboratoriesand extensive zoological gardens, with that of a staff ofanalytical, biological, and anatomical experts, and a numberof well-trained subordinate assistants. These requisites arenot fulfilled at the extant institutes attached to the universities,for there the personnel of the staff changes so rapidly thatthe trustworthiness of the results is endangered. What weneed is the foundation of large institutes with permanentstaffs whose members have an assured position. In theUnited States such places may be provided by the munificenceof millionaires; but in impoverished Europe, and especiallyin Germany, we must look to the State for aid. In suchmatters, thrift is out of place. Every day demands itssacrifice of the public health through errors of diet, andthereby the whole body politic is enfeebled.

But it will not suffice tha t steps should at length be takento throw light upon the biological processes of nutrition. Ofwhat avail would it be that scientific experts are fullyinformed concerning these matters, so long as the great massof the population is being ruined in health by irrationalfeeding? In addition to institutes for the biochemical studyof nutrition, there must be institutes of nutritive hygiene whosetask it will be to ensure the practical application of the theoreticalacquisitions of biochemistry, to ensure that the data of the newscience of nutrition shall be realised in daily life. The con-sciousness of the masses must be permeated with a practicalknowledge of the new science of dietetics.

22

B I B L I O G R A P H Y

(C = Chemisches Centralblatt; BZ == Zentralbl. f. Biochem. u.Biophys.; BPh = Ber. ges. Physiol. u. Pharm.)

1. RIESELL. In Hoppe-Seylers Med.-chem. Untersuchungen. 1868.2. SCHETELIG. Arch, pathol. Anat. 1877, 82.3. G. LUNIN. Zschr. physiol. Chem. 1881, 5, 31.4. E. LEHMANN. Berl. klin. Wschr. 1882, Nr. 21.5. T. BARLOW. Med.-chirurg. transact. 1883, 46, 159.6. TEREG and ARNOLD. Arch. ges. Physiol. 1883, 32, 122.7. KGNINGER. D. Arch. klin. Med. 1884, 34.8. A. URBEANU. Atiologie der Pellagra vom chemischen Stand-

punkt aus. Bukarest, 1884.9. K. TAKAKI. Sei-i-k-wai 1885, 4, August.

10. Sei-i-k-wai 1886, 5, April.11. Sei-i-k-wai 1887, 6, 73.X2. Sei-i-k-wai 1888, 7, 187.13. Med. a. Surg. History of the War of the Rebellion. I, T. 3,

Chap. 8. Washington, 1888.14. C. EIJKMAN. Geneesk. Tijdschr. v. Nederl.-Indie 1890, 30, 295.15. C. VON NOORDEN. Lehrbuch der Pathologie des Stofiwechsels.

1893.16. E. LEHMANN. Berl. klin. Wschr. 1894, Nr. 23.17. T. BARLOW. Lancet 1894, II, 1075.18. T. SMITH. U.S. Dept. Agric. Bureau Anim. Ind. Ann. Rept.

1895-96, 172.19. C. EIJKMAN. Geneesk. Tijdschr. v. Nederl.-Indie 1896, 36, 214.20. STRAUSS. Verh. d. 14. Kongr. f. inn. Med. Wiesbaden, 1896.21. Zschr. klin. Med. 1897, 31.22. HERXHEIMER. Berl. klin. Wschr. 1897, Nr. 20.23. C. EIJKMAN. Janus 1897, 2> 23-24. Arch, pathol. Anat. 1897, 148, 523.25. Arch, pathol. Anat. 1897, 149, 187.26. Geneesk. Tijdschr. v. Nederl.-Indie 1898, 38, 275.27. STEINITZ. Arch. ges. Physiol. 1898, 72, 75.28. C. A. HERTER. Journ. Exper. Med. 1898, 3, 293.29. ZADIK. Arch. ges. Physiol. 1899, 77, 1.30. LEIPZIGER. Inaug.-Diss. Breslau, 1899.31. PATON. Journ. of Physiol. 1899, 22, 333.32. EHRLICH. Inaug.-Diss. Breslau, 1900.

338

BIBLIOGRAPHY 339

33. A. DOTSCH. Arch. f. Ophthalm. igoo, 49, 405.34. F. G. JACKSON and V. HARLEY. Lancet 1900, I, 1184.35. G. GRIJNS. Geneesk. Tijdschr. v. Nederl.-Indie 1901, 41, 3.36. H. WRIGHT. Brit. Med. Journ. 1901, S. 1610.37. Studies Inst. Med. Res. Feder. Malay States 1902,11.5.38. D. J. HULSHOFF-POL. Janus 1902, 7, 524, 570.39. C. MORESCHI. Morgagni 1903, 1, 148.40. A. AMAND. La Cellule 1903, 20, 293.41. F. S. VAN LEENT. Arch. m6d. nav. 1903, 79, 275.42. F. ROHMANN. Allgem. med. Zentralztg. 1903, Nr. 1.43. B. NOCHT. Festschr. f. Rob. Koch 1903, S. 203.44. H. E. DURHAM. Brit. Med. Journ. 1904, H. 9.45. G. MAURER. Geneesk. Tijdschr. v. Nederl.-Indie 1904, 44, 336 ;

BZ 1904, 2, 542.46. M. MORI. Jahrb. Kinderheilk. 1904, 58, 175.47. E. EKELO*F. Hygiea 1904, S. 1214; BZ 1905, 3, 595.48. A. AMAND. La Cellule 1094, 21, 327.49. L. BARTENSTEIN. Jahrb. Kinderheilk. 1905, 61, 6.50. S. SCHMIDT-NIELSEN. Hygiea 1905, Febr.; BZ 1905, 3, 595.51. M. SCHUBERT. D. Arch. klin. Med. 1905, 86, 79 ; BZ 1906,

4, 687.52. E. LOOSER. Jahrb. Kinderheilk. 1905, 62, 743.53. A. D'ORMEA. Riv. pellagr. ital. 1905, 5, No. 5 ; BZ 1905, 4,471.54. R. DEVLOV. La Cellule 1906, 23, 36.55. C. WATSON and A. HUNTER. Journ. of Physiol. 1906, 34, i n .56. M. OTTO. Zschr. klin. Med. 1906, 59, H. 2/4 ; BZ 1906, 5, 497.5J. C. EIJKMAN. Arch. hyg. 1906, 58, 150.58. F. G. HOPKINS. Analyst 1906, 31, 385.59. D. J. HULSHOFF-POL. Geneesk. Tijdschr. v. Nederl.-Indie

1906, 46, 477.60. K. TAKAKI. Lancet 1906, I, 1369, 1451, 1520.61. New York Med. Journ. 1906, 83, 1161.62. A. HOLST. Norsk, mag. f. lagevidensk. 1907, 68, June; BZ

1907, 6, 417.63. Journ. of Hyg. 1907, 7, 619; BZ 1908, 7, 123.64. und T. FROLICH. Norsk, mag. f. lagevidensk. 1907, 70,

72 ; BZ 1907, 6, Z57.65. Journ. of hyg. 1907, 7, 634; BZ 1908, 7, 123.66. W. L. BRADDON. Causes and Prevention of Beriberi. Rebman

Co., London and New York, 1907.67. M. IDE. Zentralbl. Bakteriol. 1907, 18, II, 193.68. D. J. HULSHOFF-POL. Geneesk. Tijdschr. v. Nederl.-Indie

1907, 47, 688.69. C. ROSE. D. Monatsschr. Zahnheilk. 1908, 26, H. 1/6.jo. Erdsalzarmut und Entartung. Jul. Springer, Berlin, 1908.71. G. GRIJNS. Geneesk. Tijdschr. v. Nederl.-Indie 1908, 4$.72. F. ROHMANN. Allgem. med. Zentralztg. 1908, Nr. 9.73. H. SCHAUMANN. Arch. Schiffs- u. Trop.-Hyg. 1908, 12, 37.

340 VITAMINS

74. B. NOCHT. Arch. Schiffs- u. Trop.-Hyg. 1908, 12, Beiheffc 5.75. F. TSUZUKI. Arch. Schiffs- u. Trop.-Hyg. 1908, 12, H. 12 ;

BZ 1908, 7, 675.76. H. J. WATERS. Proc. Soc. Prom. Agl. Science 1908, 29, 71.77. C. TIRABOSCHI. Eiv. pellagr. ital. 1908, 8, H. 2 ; BZ 1909,

8, 220.78. L. FINDLAY. Brit. Med. Journ. 1908, II, 13.79. G. GRIJNS. Geneesk. Tijdschr. v. Nederl.-Indie 1909, 49.80. C. BEZZOLA. SOZ. med. e chir. 1909; BZ 1909, 8, 787.81. D. J. HULSHOFF-POL. Geneesk. Tijdschr. v. Nederl.-Indie

1909, 495 116.82. J. A. SCHABAD. Arch. Kinderheilk. 1909, 52, 47.83. Arch. Kinderheilk. 1909, 52, 68.84. H. FRASER and A. T. STANTON. Studies Inst. Med. Res. Fed.

Malay States 1909, Nr. 10.85. H. FRASER and A. T. STANTON. Lancet 1909, I, 451.86. E. B. HART, E. V. MCCOLLUM and F. G. FULLER. Amer. Journ.

Physiol. 1909, 23, 246.. 87. PUTTER. Zschr. allgem. Physiol. 1909, 9, 147.

88. E. SCHLOSS. Biochem. Zschr. 1909, 18, 14.89. G. W. K. DE JONGE. Geneesk. Tijdschr. v. Nederl.-Indie 1909,

49, 165.90. H. SCHAUMANN. Arch. Schiffs- u. Trop.-Hyg. 1909, 13,

Beiheft 6, 82.91. E. SCHLOSS. Biochem. Zschr. 1909, 229 283.92. J. E. LANE-CLAYPON. Journ. of Hyg. 1909, 9, 233.93. W. STEPP. Biochem. Zschr. 1909, 22, 452.94. H. FRASER and A. T. STANTON. Lancet 1909, II, 406.95. E. V. MCCOLLUM. Amer. Journ. Physiol. 1909, 25, 120.96. ETIENNE und FRITSCH. Journ. physiol. pathol. g6n. 1909,

11, 1084.97. R. BERG. Biochem. Zschr. 1910, 30, 107.98. H. J. WATERS. Proc. Soc. Prom. Agl. Science 1910, 30, 70.99. J. A. SCHABAD. Arch. Kinderheilk. 1910, 53, 380.

100. A. HOLST. Nord. med. ark. 1910, II, Anhang 328 ; BZ 1910,10, 931.

101. T. FRSLICH. Nord. med. ark. 1910, II, Anhang 339; BZ1910, 10, 931.

102. V. FURST. Nord. med. ark. 1910, II, Anhang 349; BZ 1910,10, 931.

103. A. PATTA. Arch, di farmacol. 1910, 9, 1 ; BZ 1910, 10, 620.104. H. CHICK, E. M. HUME and R. F. SKELTON. Journ. of Physiol.

1910, 40, 404.105. A. HOLST and T. FRSLICH. Norsk, mag. f. lagevidensk. 1910,

No. 3 ; BZ 1910, 10, 231.106. J. A. SCHABAD. Arch. Kinderheilk. 1910, 54, 83.107. T. FROLICH. Norsk, mag. f. lagevidensk. 1910, No. 3 ; BZ

1910, 10, 231.

BIBLIOGRAPHY 341

108. H. FRASER and A. T. STANTON. Philipp. Journ. of Science1910, 5> B, 55; BZ 1910, io? 861.

109. J. DE HAAN. Philipp. Journ. of Science 1910, 5, B, 65 ; BZ1910, 10, 862.

no . H. C. HIGHET. Philipp. Journ. of Science 1910, 5, B, 73.i n . H. ARON. Philipp. Journ. of Science 1910, 5, B, 81.112. H. ARON and F. HOCSON. Philipp. Journ. of Science 1910, 5,

B, 81, 98 ; BZ 1910, 10, 643.113. G. SHIBAYAMA. Philipp. Journ. of Science 1910, 5, B, 123.114. C. K. FRANCIS and P. F. TROWBRIDGE. Journ. Biol. Chem.

1910, 7, 81.115. P. F. TROWBRIDGE and L. STANLEY. Journ. Ind. Eng. Chem.

1910, 2, 202.116. <3. HOLSTI. Skand. Arch. Physiol. 1910, 23, 143.117. A. M. COLLODI. Arch, di farmacol. 1910, 9, 139 ; BZ 1910,

10, 620.118. Arch, di farmacol. 1910, 9, 145 ; BZ 1910, 10, 620119. A. LIPSCHUTZ. Arch, exper. Pathol. u. Pharmakol. 1910, 62,

210, 244.120. F. ROGOZINSKI. Anz. Akad. Wissensch. Krakau 1910, B.S. 260.121. I. FUJITANI. Arch, internat. pharm. et therap. 1910, 20, 287;

BZ 1910, 10, 994.122. H. SCHAUMANN. Arch. Schiffs- u. Trop.-Hyg. 1910, 14,

Beiheft 8.123. E. SCHLOSS. D. med. Wschr. 1910, Nr. 22.124. D. J. HULSHOFF-POL. Arch. Schiffs- u. Trop.-Hyg. 1910, 14,

Beiheft 9.125. M. GLOGNER. Die JLtiologie der Beriberi. Joh. A. Barth,

Leipzig, 1910.126. G. ALESSANDRINI. Policlinico, Sez. prat. 1910, 15. May and

26. June; BZ 1910, 10, 994.127. W. HAUSMANN. Wien. med. Wschr. 1910, Nr. 36 ; BZ 1910,

10, 933-128. W. G. ELLIS, Brit. Med. Journ. 1910, II, 935.129. B. ASFORD. II. Congr. internat. d'hyg. aliment. Brussels 1910,

Sect. II, 251.130. E. SCHLOSS. Jahrb. Kinderheilk. 1910, 71, 298.131. H. FRASER and A. T. STANTON. Transact. Soc. Trop. Med.

Hyg. 1910, I I I ; Lancet 1910, II, 1755.132. J. HORBACZEWSKI. Casopis lekar. ceskych. 1910, No. 37-39;

BZ 1910, 10, 932,133. Y. TERAUCHI. Saikingakuzashi (Tokio) 1910, No. 179; BZ

1911, 11, 719.134. J. and N. CRONHEIM. Zschr. physik. diatet. Therap. 1910, 14.135. H. ARON. Philipp. journ. of Science 1911, 6, B, 1.136. U. TSUZUKI and T. SHIMAMURA. Journ. Tokyo chem. soc.

1911, 32; BZ 1911, 12, 11.137. C. FUNK. Journ. of physiol. 1911, 43, 50.

342 VITAMINS138 W P CHAMBERLAIN Philipp Journ of Science 1911, 6, B, 13319 R MORI Japan und seme Gesundheitspilege Tokyo igii,

308140 Mitteilungen der Beribenkommission Tokyo 1911141 R BERG Emfluss des Abbruhens auf den Nahrwert unserer

Gemusekost, Weisser Hirsch, 1911142 G TIZZONI Pathologica 1911, 3, 67, BZ 1912, 13, 60143 J P GREGERSEN Zschr physiol Chem 1911, 71, 49144 G ViDONiandS GATTI RIV pellagr ital 1911,10, BZ1911,

11, 488145 W P CHAMBERLAIN, BLOOMBERGH and KILBOURNE Phikpp.

Journ of Science 1911, 6, B, 165 , BZ 1911, 12, 505146 SHIGA and KU&AMA Arch Schiffs- u Trop-Hyg 1911, 15,

Beiheft 3147 E SCHLOSS Jahrb Kmderheilk 1911, 74, 91148 W STEPP Zschr Biol 1911, 57, 135149 H ARON and F HOCSON Biochem Zschr 1911, 32, 189,

C 1911, 82, II 158150 T B OSBORNE and L B MENDEL Carnegie Inst "Washington

1911, publ 156, I, 32151 V G HEISER Philipp Journ of Science 1911, 6, B 229152 Journ Araer Med Assoc 1911, 56, 1238153 H RAUBITSCHEK Zentralbl Baktenol 1911, 57, 193, BZ

1911, 11, 376154 A ORGLER Monatschr. Kmderheilk 1911, 10, 373155 C FUNK Journ of physiol 1911, 43, 395 , BZ 1912, 13, 275156 W P CHAMBERLAIN and E B VEDDER Phibpp Journ of

Science 1911, 6, B, 251, BZ 1911, 12, 505157 H SCHAUMANN Arch Scmffs- u Trop-Hyg 1911, 15,252.158 P RONDONI Lo Spenment 1911, 65, 265 , BZ 1912, 12, 756.159 H FRASER and A T STANTON Studies Inst Med Res.

Fed Malay States 1921, Nr 12160 Journ Trop Med Hyg 1911, 14, 333 , 349, 365161. L LUCATELLO and M V CARLETTI Accad med Padova 28

April 1911, BZ 1912, 13, 68162 L PRETI and L POLLINI Rif med 1911, No 27, BZ 1912,

13, 54163 PORGES, LEIMD6RFER and MARKOVICI Zschr khn Med 1911,

73, 389164 P RONDONI Lo Spenment, 1911, 65, 307 , BZ 1912, 12, 716165 G C E SIMPSON and E S EDIE Ann Trop Med Parasxt.

1911, S» 3i3» BZ 1911, 12, 415166 E SCHLOSS Monatschr Kmderheilk 1911, 9, 636167 A HOLST Transact Soc Trop Med Hyg 1911, 5, 75168 W P CHAMBERLAIN and E B VEDDER Philipp Journ of

Science 1911, 6, B, 396 , BZ 1912, 14, 265169 C VALLARDI Rif med 1911, No 36, BZ 1912, 13, 71170 G TI7ZONI Zentralbl Baktenol 1911, 61, 403, BZ 1912,

BIBLIOGRAPHY 343171 A HOLST M6d revue 1911, 28, 436, BZ 1911, 12, 419172 BREAUDAT Journ pharm et chim 1911, (2), 4, 447, BZ

1911, 12, 577173 H SCHAUMANN Transact soc trop med hyg 1911, 5, 59174 M MOSZKOWSKI Arch Schiffs- u Trop -Hyg 1911, 15, 653 ,

BZ 1912, 13, 143175 C EIJKMAN Arch Schiffs-u Trop-Hyg 1911,15,698176 Arch Schiffs- u Trop-Hyg 1911, 15, 699, BZ 1911,

12, 505177 H SCHAUMANN Arch Schiffs- u Trop-Hyg 1911, 15, 728,

BZ 1911, 12, 716178 G TIZZONI Pathologica 1911, 3, Nr 59 , BZ 1911, 12, 322179 M V CARLETTI Gazz osped 1911, 32, 731 BZ 1912,

13,68180 Gazz osped 1911, 32, 861, BZ 1912, 13, 68181 A SCHEUNERT A SCHATTKE and E LOTZSCH Biochem

Zschr 1911, 36, 240182 E A COOPER and C FUNK Lancet 1911, II 1267 , BZ 1911.

I2> 577183 C C BASS Journ Amer Med Assoc 1911, 57, 1648, BZ

1912 12, 652184 L V CAMURRI Congr pellagr ital Udine 19H, BZ 1911,

11, 86185. M GLOGNER Die Nahrungsmitteltheorien uber die Ursache der

Beriberi in kntischer Beleuchtung Joh A Barth, Leipzig,1912

186 A HOLST and T FROLICH Zschr f Hyg 1912, 72, 1 , BZ1912, 13, 662

187 V FURST Norsk mag f lagevidensk 1912, 1, BZ 1912,13, 663

188 D J HULSHOFF-POL Geneesk Tijdschr v Nederl -Indie1912, 52, 11, BZ 1913. *4> 399

189 VOLPINO, MARIANI, BORDONI and ALPAGO-NOVELLA RIVd'lg e san pubbl 1912 23 BZ 1913 14, 936

190 VOLPINO, BORDONI and ALPAGO-NOVELXA RIV d'lg e sanpubbl 1912 23, BZ 1913, 15, 195

191 W P CHAMBERLAIN and E B VEDDER Bull Manilla MedSoc 1912

192 C ROSE Balneol Ztg 1912193 Veroff d Zentralstelle f Balneol 1912194 Emwirkung von Erdsalzen usw auf Ausscheidung und

Zusammensetzung des Harns Springer, Berlin, 1912195 A ORGLER Ergebn inn Med Kinderheilk 1912 8, 142196 W P CHAMBERLAIN, E B VEDDER and R R WILLIAMS

Phihpp Journ of Science 1912, 7, B, 39 BZ 1913, 14, 716197 C FUNK Journ of physiol 1912, 44, 50 , BZ 1912, 13, 662198 G GRIJNS Geneesk Tijdschr v Nederl -Indie 1912, 52, 50 ,

BZ 1913, 14, 399199. G FINGERLING Biochem. Zschr. 1912, 38, 448

344 VITAMINS

200. H. MACLEAN. Philipp. Journ. of Science 1912, 7, B, 67; BZ1912, 14, 108.

201. V. ANDREWS. Philipp. Journ. of Science 1912, 7, B, 67; BZ1912, 14, 108.

202. F. G. HOPKINS . Journ. of Physiol. 1912, 44, 425 ; B Z 1912,

13, 814.203. V. FURST. Zschr. Hyg. 1912, 72, 121 ; BZ 1912, 13, 663.204. T. FROLICH. Zschr. Hyg. 1912, 72, 155 ; BZ 1912, 13, 663.205. C. FUNK. Journ. of physiol. 1912, 45, j$ ; BZ 1912, 13, 819.206. Brit. Med. Journ. 1912, II , 116.207. Journ. State Med. 1912. 20, 341.208. E. SCHLOSS. Berl. klin. Wschr. 1912, Nr. 24.209. TSUZUKI, SHIMAMURA and S. ODAKE. Journ. trop. med. hyg.

1912, 15, 352.210. Biochem. Zschr. 1912, 43, 89; BZ 1912, 13,

904.2 1 1 . C. H A R T . A r c h , e x p e r . P a t h o l . P h a r m a k o l . 1 9 1 2 , 2 0 8 , H . 2 ;

B Z 1 9 1 2 , 1 3 , 9 0 3 .2 1 2 . C. L . A L S B E R G . S o u t h e r n M e d . J o u r n . 1 9 1 2 , 1 7 0 ; B Z

1912 , 1 4 , 1 8 4 .2 1 3 . F . L U S T a n d L . K L O C K M A N N . J a h r t x K i n d e r h e i l k . 1912 ,

7 5 , 6 6 3 .2 1 4 . G. N I S T I C O . L a v o r a 1 9 1 2 , 4 , 193 ; B Z 1 9 1 2 , 1 3 , 2 7 6 .

2 1 5 . H . M A C L E A N . J o u r n . of P h y s i o l . 1 9 1 2 , 4 5 , 3 ; B Z 1912 ,

1 4 , 1 0 8 .

2 1 6 . L . P R E T I u n d L . P O L L I N I . S O C . L o m b . s z i e n z . m e d . e b i o l . 1 .

M a r c h 1912 ; B Z 1 9 1 2 , 1 4 , 2 6 .

2 1 7 . T . B . O S B O R N E a n d L . B . M E N D E L . A m e r . J o u x n . P h y s i o l .

1912 , 2 9 , X I I ; B Z 1 9 1 2 , 1 3 , 1 4 0 .

2 1 8 . W E L L M A N , B A S S a n d E U S T I S . N e w O r l e a n s M e d . S u r g . J o u r n .

1912 , 6 5 , 1 9 7 ; B Z 1 9 1 3 , 1 4 , 9 0 9 .

2 1 9 . H . S C H A U M A N N . B u l l . s o c . p a t h o l . e x o t . 1912 , 5 , 1 2 5 .

2 2 0 . E D I E , E V A N S , M O O R E , S I M P S O N a n d W E B S T E R . B i o c h e m

J o u r n . 1912 , 6 , 2 3 4 ; B Z 1912 , 1 3 , 9 0 3 .

2 2 1 . P . L A R U E . I n t e r n a t . B e i t r . E r n a h r u n g s s t o r . 1 9 1 2 , 4 , 2 4 6 ,

B Z 1 9 1 3 , 1 4 , 3 3 5 .

2 2 2 . V . G. H E I S E R . M e d . R e c . 1912 , 8 1 , 5 1 6 .

2 2 3 . R . P . S T R O N G a n d B . C. C R O W E L L . P h i l i p p . J o u r n . of S c i e n c e

1912 , 7 , B , 2 7 1 ; B Z 1 9 1 3 , 1 4 , 7 1 7 .

2 2 4 . H . W I E L A N D . A r c h , e x p e r . P a t h o L 1 9 1 2 , 6 9 , 2 9 3 ; B Z 1 9 1 2 ,

1 4 , 2 8 .

2 2 5 . T . B . O S B O R N E , L . B . M E N D E L a n d E . L . F E R R Y . Z s c h r .

P h y s i o l . C h e m . 1912 , 8 0 , 3 0 7 ; B Z 1 9 1 2 , 1 4 , 2 5 .

2 2 6 . H . S C H A U M A N N . A r c h . Sch i f f s - u . T r o p . - H y g . 1 9 1 2 , 1 6 , B e i h e f t6* I37-

227. E. SCHLOSS. Zschr. Kinderheilk. 1912, 3, 441.228. Monatschr. Kinderheilk. 1912, 10, 499.229. V. G. HEISER. Internat. clin. Philadelphia 1912, 22, II, xi6.

BIBLIOGRAPHY 345

230. ETIENNE. Journ. physiol. pathol. g&n. 1912, 14, 108.231. H. EPPINGER und A. ARNSTEIN. Zschr. klin. Med. 1912, 74,

324; BZ 1912, 13, 163.232. H. SCHAUMANN. Arch. Schiffs- u. Trop.-Hyg. 1912, 16, 349 ;

BZ 1912, 13, 578.233. H. MACLEAN. Biochem. Journ. 1912, 6, 355 ; BZ 1913, 14, 613.234. W. STEPP. Zschr. Biol. 1912, 59, 366 ; BZ 1913, 14, 396.235. E. B. VEDDER. Philipp. Journ. of Science 1912, 7, B, 415 ;

BZ 1913, 14, 716.236. A. HOLST. Transact. 15. Internat. Congr. Hyg. Demograph.

Washington, 1912, II, Sect. 2, 583.237. E. B. VEDDER. Transact. 15. Internat. Congr. Hyg. Demograph.

Washington, 1912, V, Sect. 2, 671.238. and E. CLARK. Philipp. Journ. of Science 1912, 7, B, 423.239- Brit. Med. Journ. 1912, II, 1731.240. GOUZIEN. Ann. d'hyg. et med. colon. 1912, 15, 445; BZ

1913, 14. 909.241. FARGIER. Ann. d'hyg. et m6d. colon. 1912, 15, 491 ; BZ 1913,

14, 910.242. L. BAUMANN and C. P. HOWARD. Arch. Intern. Med. 1912,

9, 665.243. GERARD. Ann. inst. Pasteur, 1912, 26, 986.244. P. RONDONI. Lo Speriment. 1912, 66, 447 ; BZ 1913, 15, 196.245. O. UMMES. Zschr. Immunitatsforsch. 1912, 13, 461 ; BZ

1912, 13, 703.246. T. B. OSBORNE and L. B. MENDEL. Journ. Biol. Chem. 1912,

12, 473 ; BZ 1913, 14, 325.247. ONODERA, NAKAMURA and TATENO. Mitteil. med. Ges. Tokyo

1912, 26, 23 ; BZ 1913, 14, 553.248. YAMIGAWA, KOYAMA, MIDORIKAWA and MOGI. Mitteil. med.

Ges. Tokyo 1912, 26, 23 ; BZ 1913, 14, 553.249. C. HART. Jahrb. Kinderheilk. 1912, 76, 507 ; BZ 1913, 14, 552.250. A. HIRSCHFELDER. Zschr. Bakteriol. 1912, 66, 537 ; BZ 1913,

14. 353.251. G. SHIBAYAMA. Arch. Schiffs- u. Trop.-Hyg. 1912, 16, 721 ;

BZ 1913, 14, 399.252. H. SCHAUMANN. Arch. Schiffs- u. Trop.-Hyg. 1912, 16, 825.253. O. HERBST. Jahrb. Kinderheilk. 1912, 76, Supplem., 14.254. Jahrb. Kinderheilk. 1912, 76, Supplem., 40.255. T. B. OSBORNE and L. B. MENDEL. Journ. Biol. Chem. 1912,

13. 233.256. R. BERG. Ergebn. ges. Zahnheilk. 1912, 5, 478.257. H. FRASER and A. T. STANTON. Lancet 1912, II, 1005 ; BZ

1913, 14, 340.258. S. WEISER. Biochem. Zschr. 1912, 44, 279.259. L. HIRSCHSTEIN. Zschr. physikal. diatet. Therap. 1912, 16, 706.260. F. ROLLY. Munchn. med. Wschr. 1912, 68, 1201, 1274; BZ

1912, 13, 679.

346 VITAMINS

261. J. M. LITTLE. Journ. Amer. Med. Assoc. 1912, 58, 2025;BZ 1913, 14, 632.

262. C. LOVELACE. Journ. M«d. Amer. Assoc. 1912, 58, 2134 I &£1913, 14, 552-

263. H. RATJBITSCHEK. D. rned. Wsclir. 1912, 2169; s z l9*3>I4> 369.

264. A- Lui und M. BACCELLI. Note e riv. di psich. 1913, o, 1;BZ 1913, 17, 877.

265. C. VOEGTLIN and C. TOWXES. Journ. of PKarm. I9*3> 5* 6 7 ;BZ 1913, 16, 23.

266. C. FUN-K. Biochem. Journ. 1913, 7, 81 ; BZ 1913, 15, 227.267. E. G. HOPKINS and A. NEVILLE. Biochem. Journ. 1913» 7>

96; BZ 1913, 14, 628.268. C. FUNK. Biocliern. Journ. 1913, 7, 211; BZ 1913, I5> 235-269. E.A. COOPER. Biochem. Journ. 1913,7,268 ; BZ 1913. *5> 642.270. L. NICHOLAS. Joizrn. oiHyg. 1913, 13,149 i BZ I9*3> 15f 768-271. H. RICHTER. Zschr. ges. Neurol. 1913, 21, 172; BZ I9i4> J^>

369.272. SAWAZAKI. Mitteil. med. Ges. Tokyo 19*3* 3 ; BZ 1913,

IS 314.273. C. FUNK. Journ. of physiol. 1913, 46, 173 ; BZ 1913, 15, 643.274. O. HERBST. Zschr. Kinderheilk. 1913, 7, 161.275. C. FUNK. Brit. Med. Journ. 1913, I, 814.276. E. B. TALBOTT, W. J. DOBD and H. O. PETERSON. Transact.

Amer. Pediatr. Soc. 1913, 25, 195; Boston Med. Surg.Journ. 1913, 169, 232.

277. Boston Med. Surg. Journ. 1913, 169, 233.278. W. J. DODD. Boston Med. Surg. Joura. 1913* 169, 237.279. E. V. MCCOLLUM and M. DA.vis. Journ. Biol. Chem. 1913,

155 167.280. R. WHEELER. Journ. Exper. Zool. 1913, 15, 209.281. C. WELLHAN, A. C. EXJSTIS and L. C. SCOTT* Amer. Joura.

Trop. Dis. Pre^. Med. 1913, 1, 295.282. LIECHTI aad TRTJNINGER. Landw. Jakrb. d. Scliweiz 1913, 459.283. H. STEENBOCK and E. B. HART. Joura, BioL Chem. 1913,

14, 59-284. E. B. VEEDER and E.. E.. WILLIAMS. Philipp. Journ. of Science

1913, 8, B, 175; BZ 1914, 16, 169.285. J. NICOLAIDI. Rev. stiiatz. med. 1913, 9, No. 6 ; BZ 1913,

14, 676.286. F. SMITH and HASTINGS. Jourri. Roy. Army Med. Corps 1913,

20, 202; BZ 1913, 14, 909.287. E. DURLACH. Arch. Exper. Pathol. Pliann. 1913, 71, 210.288. GROSSER. Ergebn. inn. Med. Kinderheilk. 1913, n * 119.289. E. ABDERHALDEK and A. E. LAMP£. Zschr. exper. Med. 1913,

1, 296; BZ 1913, 15, 227.290. E. SCHLOSS. Jahrb. Kinderheilk. 1913, 78, 694.291. E. A. COOPER. Brit. Med. Journ. 1913, I, 722.

BIBLIOGRAPHY 347

292. W. STEPP. Zschr. Biol. 1913, 62, 405.293. E. CENTANNI und C. GALASSI. VIII. Rmnione soz. ital. dipatol.

Pisa March 1913 ; BZ 1914, 16, 370.294. K. BIRKNER and R. BERG. Zschr. klin. Med. 1913, 77, 5/6.295. T. B. OSBORNE, L. B. MENDEL, E. L. FERRY and A. J. WAKE-

MAN. Joum. Biol. Chem. 1913, 15, 311 ; BZ 1913, 16, 17.296. E. B. MEIGS and H. L. MARSH. Journ. Biol. Chem. 1913, 16,

147.297. C. EIJKMAN. Arch. Schiffs- u. Trop.-Hyg. 1913, 17, 328; BZ

1913, 15, 227.298. PORGES, LEIMDORFER and MARKOVICI. Zschr. klin. Med. 1913,

77, 446.299. R. J. CARNEIRO. Monatschr. Kinderheilk. 1913, 12, 333 ; BZ

1914, 16, 308.300. R. B. GIBSON. Philipp. Journ. of Science 1913, 8, B. 315.301. A. HOLST and T. FROLICH. Zschr. Hyg. 1913, 75, 334 ; BZ

1913, 15, 643.302. J. NICOLAIDI. Rev. stiintz. med. 1913, 9, May; BZ 1913,

*5> 9 i i .303. C. FUNK. Journ. of Physiol. 1913, 47, 389 ; BZ 1914, 16, 310.304. M. BARSICKOW. Biochem. Zschr. 1913, 48, 418; BZ 1913,

14, 840.305. T. B. OSBORNE, L. B. MENDEL, E. L. FERRY and A. J. WAKE-

MAN. Journ. Biol. Chem. 1913, 16, 423 ; BZ 1914, 16, 305.306. R. BERG. Die Nahrungs- u. Genussmittel. Holze & Pahl,

Dresden, 1913.307. E. B. VEDDER. Philipp. Journ. of Science 1913, 8, B. 423 ;

BZ 1914, 16, 240.308. R. B. GIBSON. Philipp. Journ. of Science 1913, 8, B. 469.309. KLEIMUNGER. Zschr. ges. neurol. 1913, 16, 586; BZ 1913,

15, 314-310. H. SCHATJMANN. Arch- Schiffs- u. Trop.-Hyg. 1913, 17, 433 ;

BZ 1913, 15, 866.311. E. A. COOPER. Journ. of Hyg. 1913, 12,436 ; BZ 1913,14, 632.312. G. ALESSANDRINI and A. SCALA. Boll. real, accad. med. Roma

1913, 39^ 7; BZ 1914, 17, 392.313. SEGAWA. Mitteil. med. Ges. Tokyo 1913, 27, 7; BZ 1913,

15. 154-314. E. B. VEDDER. Beriberi. John Bale, Sons & Danielsson,

Ltd., London, 1913.315. C. FUNK. Ergebn. d. Physiol. 1913, 13,124; BZ 1913, 15, 866.316. G. BOSTOCK. Zschr. physiol. Chem. 1913, 84, 469 ; BZ 1913,

15, 204.317. C. FUNK. Journ. of Physiol. 1913, 45, 488 ; BZ 1913, 14, 716.318. V. C. MYERS and M. S. FINE. Amer. Journ. Med. Science

1913, 145, 705; BZ 1913, 15, 154.319. R. BERG. Verhandl. d. Ges. d. Naturf. u. Arzte, Vienna 1913,

Vol. II, 2.

348 VITAMINS

320. J. TSUZUKI. D. R. P. 266211 v. 20. Oct. 1913 ; BZ 1913, 16,102 ; Amer. P. 1058927 v. 15. April 1913 ; Chem.-Ztg. 1913,37, Rep. 513.

321. C. EIJKMAN. Miinchn. med. Wschr. 1913, 871 ; BZ 1913*5> 77

322. C. FUNK. Munchn. med. Wschr. 1913, 1997; B Z

15, 800.323. Munchn. med. Wschr. 1913, 2614; BZ 1913, 16, 170.324. Zschr. physiol. Chem. 1913, 88, 352 ; BZ 1914, 16, 369.325. F. G. HOPKINS. Lancet 1913, II, 1309-326. W. C. HARRIS. Journ. Arner. Med. Assoc. 1913. 60, 1949 ;

BZ 1913, 15, 533.327. CARBONE and CAZZAMALLI. Giorn. real. soz. ital. d'ig. 1914*

5» 5*» 99> 151 ; B Z 1914* J7> 635.328. J. F. SILER, T. E. GARRISON and W. J. MCNEAL. Journ. Amer.

Med. Assoc. 1914, 62, 8; BZ 1914, 16, 931.329. E. A. COOPER, H. Journ. Hyg. 1914, 14, 12.330. H. FRASER and A. T. STANTON. Lancet 1914, I, 96.331. C. FUNK. Lancet 1914, I, 98.332. E. SCHLOSS and L. FRANK. Biochem. Zschr. 1914, 60, 378.333. R. BERG. Zschr. angew. Chem. 1914, 27, 148.334. C. FUNK. Zschr. physiol. Chem. 1914, 89, 373; BZ 1914,

16, 760.335. Zschr. physiol. Chem. 1914, 89, 378; BZ 1914, 16, 760.336. R. TASAWA. Zschr. exper. Pathol. 1914, 17, 27; BZ 1915,

17, 920.337. P. ALBERTONI and P. TULLIO. Real accad. scienze ist. di

Bologna 11 Jan. 1914 ; BZ 1915, 17, 684.338. G. ALESSANDRINI and A. SCALA. Pellagra. Tipogr. nazional.

Roma 1914; BZ 1915, 17, 709.339. L. FRANK and E. SCHLOSS. Monatschr. Kinderheilk. 1914,

*3> 272.340. E. SCHLOSS. Jahrb. Kinderheilk. 1914, 79, 40.341. Jahrb. Kinderheilk. 1914, 79, 194.342. L. S. PALMER and C. H. ECKLES. Journ. Biol. Chem. 1914,

17, 191.343. R. B. GIBSON and I. CONCEPCION. Philipp. Journ. of Science

1914, 9, B, 119.344. J. L. MORSE. Transact. Amer. Pediatr. Soc. 1914, 26, 61.345. G. VOLPINO. Gazz. int. med. e chir. 1914, No. 14; BZ 1915,

17, 707.346. A. D. EMMET, H. S. GRINDLEY, W. E. JOSEPH and R. H.

Williams. Illinois Agr. Exper. Stat. Bull. 1914, 168, 85 ;BZ 1916, 18, 568.

347. S. WEISER. Biochem. Zschr. 1914, 66, 95 ; BZ 1915, 17, 685.348. RONDONI. Riv. pellagr. ital. 1914; BZ 1915, 17, 707.349. T. B. OSBORNE and L. B. MENDEL. Journ. Biol. Chem. 1914,

17, 325 ; BZ 1914, 17, 20.

BIBLIOGRAPHY 349

350. T. B. OSBORNE and L. B. MENDEL. Journ. Biol. Chem. 1914,17, 401 ; BZ 1914, 17, 19.

351. E. FREUDENBERG. Monatschr. Kinderheilk. 1914, 13, 141 ;BZ 1915, 17, 734.

352. K. SCHNYDER. Arch. Verdauungskr. 1914, 20, 147 ; BZ 1914,*7> 54°-

353- W. STERNBERG. Arch.. Verdauungskr. 1914, 20, 200.354. R. WHEELER and A. BIESTER. Amer. Journ. Dis. Childr. 1914,

7, 169.355- W. R. OHLER. Journ. Med. Res. 1914, 31, 239.356. G. ALESSANDRINI and A. SCALA. Zschr. Chemotherap. 1914,

2, 156; BZ 1914, 17, i n .357. C. FUNK. Journ. of physiol. 1914, 47, Proc. ; BZ 1914,

16, 677.358. and M. DOUGLAS. Journ. of Physiol. 1914, 47, 474

BZ 1914, 16, 677.359- J- NTTZESCU. Soc, biol. 1914, 76, 829; BZ 1914, 17, 380.360. G. VOLPINO. Pathologica 1914, 5, 174 ; BZ 1914, 16, 370.361. H. SCHATJMANN. Arch. Schiffs- u. Trop.-Hyg. 1914, i8,Supplem.,

6; BZ 1914, 17, 481.362. E. A. COOPER. Biochem. Journ. 1914, 8, 250 ; BZ 1914, 17,481.363. J. F. SILER, P. E. GARRISON and W. J. MCNEAL. Arch. Intern.

Med. 1914, 14, 289.364. Arch. Intern. Med. 1914, 14, 293; Journ.

Amer. Med. Assoc. 1914, 63, 1090; BZ 1915, 17, 684.365 . I. Progr. Rept. Rob. M. Thompson Pellagra

Commission New York Post Graduate Med. School andHosp., New York, 1914.

366. G. BARGER. The Simpler Natural Bases. Longmans, Green& Co., London and New York, 1914.

367. W.J. ARNOLD. Brit. Med. Journ. 1914, 299 ; BZ 1914, 16, 536.368. P. A. NIGHTINGALE. Brit. Med. Journ. 1914, 301; BZ

1914, 16, 536.369. M. SEGAWA. Arch, exper. Pathol. 1914, 215, 404 ; BZ 1914,

16, 760.370. T. B. OSBORNE and L. B. MENDEL. Journ. Biol. Chem. 1914,

18, 95; BZ 1914, *7> 33O.371. E. A. COOPER. Biochem. Journ. 1914, 8, 347 ; BZ 1918,19,648.372. W. L. BRADDONand E. A. COOPER. Journ. of Hyg. 1914,14, 331.373. A. F. HESS and M. FISH. Amer. Journ. Dis. Childr. 1914,8,385.374. C. FUNK and A. MACALLUM. Zschr. physioL Chem. X914, 92,

13 ; BZ 1914, 17, 480.375. C. FUNK. Journ. of physioL 1914, 48, 228 ; BZ 1914, 17, 181.376. and E. C. v. SCHONBORN. Journ. of PhysioL 1914, 48,

328; BZ 1914, 17, 480.377. SCHOLZ and HINKEL. Arch. klin. Med. 1914, 1x2, 334.378. E. SCHLOSS. Arch. Kinderheilk. 1914, 63, 359.379. Jahrb. Kinderheilk. 1914, 79, 539.

350 VITAMINS

380. W. L. BRADDON and E. A. COOPER. Brit. Med. Journ. 1914*I, 1348.

381. A. C. EUSTIS and L. C. SCOTT. Biochem. Bull. 1914, 3, 466.382. E. V. MCCOIXUM and M. DAVIS. Proc. Soc. Exper. Biol. Med.

1914, 11, 49.3g3# Proc. Soc. Exper. Biol. Med. 1914* " J IOI.384. P. RAIMONO. Pathologica 1914, 6, 541.385. G. SCHMORL. Ergebn. inn. Med. Kinderheilk. 1914, 13, 403.386. E. V. MCCOLLUM and M. DAVIS. Journ. Biol. Chem. 1914, 19,

245 ; BZ 1915, i8, 155.387. A. INGIER. Journ. Exper. Med. 1914,21,525 ; BZ 1915,18,253.388. C. FUNK. Die Vitamine, ihre Bedeutung fur die Physiologie

und Pathologie mit besonderer Beriicksichtigung der Avita-minosen. Bergmann, Wiesbaden, 1914.

389. DEZANI. Biochim. 1914, 4, 475; BZ 1915, 18, 155.390. J. C. DRUMMOND and C. FUNK. Biochem. Jouin. 1914, 8,

598 ; BZ 1918, 19, 693.391. E. FREISE. Monatschr. Kinderheilk. 1914, 12, 687; BZ 1914,

175 54°-392. E. CHRISOSTOMO. Actas, mem. y comunic. de la assambl. med.

y farm. Filipinas 1914; BZ 1916, 18, 659.393. S. BAGLIONT. Atti d. Real accad. d. lincei Roma 1914, 22, 721 ;

BZ 1914, 17, 636.394. W. BABES and H. JONESCU. SOC. Biol. 1914, 77, 171; BZ

1916, 18, 530.395. B. Gosio. Berl. klin. Wschr. 1914, 51, 869 ; BZ 1914, 17, 21.396. W. STEPP. D. med. Wschr. 1914, 892; BZ 1914, 17, 21.397. C. H. LAVINDER, E. FRANCIS, R. M. GRIMM and W. F. LORENZ.

Journ. Amer. Med. Assoc. 1914, 63, 1090 ; BZ 1915, 17, 765.398. C. VOEGTLIN. Journ. Amer. Med. Assoc. 1914, 63, 1090 ; BZ

1915, 17, 765-399- J- J- NITZESCU. D. med. Wschr. 1914,1614 ; BZ 1914,17,560.400. J. M. LITTLE. Journ. Med. Amer. Assoc. 1914, 63, 1287.401. S. T. DARLING. Journ. Amer. Med. Assoc. 1914, 63, 1290.402. J. GOLDBERGER. U.S. Publ. Health Repts. 1914, 29, 1683.403. W. STERNBERG. Berl. Klinik 1915, 27, 1.404. LEVA. Zschr. klin. Med. 1915, 82, 1.405. A. INGIER, Nord. med. Arkiv. 1915, 48, II, 1 ; BZ 1915, 18,159.406. J. J. NITZESCU. Bull. acad. romana 1915, 4, 1; BZ 1915,

18, 317-407. H. STEENBOCK, V. E. NELSON and E. B. HART. Bull. Exper.

Stat. Univ. Wisconsin 1915, Nx. 35 ; BZ 1918, 19, 555.408. E. V. MCCOLLUM. Journ. Biol. Chem. 1915, 19, 323; BZ

I9i5> 18, 419.409. E. B. HART and E. V. MCCOLLUM. Journ. Biol. Chem. 1915,

19, 374»' BZ 1915, 18, 313.410. H. STEENBOCK, V. E. NELSON and E. B. HART. Journ. Biol.

Chem. 1915, 19, 399; BZ 1915, 18, 312.

BIBLIOGRAPHY 351

411. A. F. HESS. Proc. Soc. Exper. Biol. New York 1915, 13, 50;BZ 1916, 18, 798.

412. J. F. SILER, P. E. GARRISON and W. J. MCNEAL. Arch. Intern.Med. 1915, 16, 98; BZ 1915, 17, 921.

413. B, W. PALMER and L. J. HENDERSON. Arch. Intern. Med.1915, 16, 109; BZ 1915, 18, 326.

414. BRUDZINSKI and CHELKOWSKI. Przeglad Lekarski 1915, 54;Centralbl. inn. Med. 1916, 37, 753.

415. C. ROSE. Arztl. Rundsch. 1915, Nr. 2.416. W. A. PERLZWEIG. Transact. Dent. Soc. New York 1915, 192.417. P. RAIMONO. Pathologica 1915, 7, 101.418. J. ALBERT. Philipp. Journ. of Science 1915, 10, B, 81.419. C. G. MCARTHUR and C. L. LUCKETT. Journ. Biol. Chem. 1915,

20, 161 ; BZ 1915, 18, 419.420. F. G. BENEDICT and P. ROTH. Journ. Biol. Chem. 1915, 20,

231; BZ 1915. 18, 313.421. R. R. WILLIAMS and N. M. SALEEBY. Philipp. Journ. of

Science 1915, 10, B, 99; BZ 1916, 18, 571.422. and B. C. CROWELL. Philipp. Journ. of Science 1915, 10,

B, 121 ; BZ 1916, 18, 573.423. T. B. OSBORNE, L. B. MENDEL, E. L. FERRY and A. J. WAKE-

MAN. Journ. Biol. Chem. 1915, 20, 351; BZ 1915, 18, 418.424. Journ. Biol. Chem. 1915,20,379; BZ 1915,18,419.425. E. V. MCCOLLUM and M. DAVIS. Journ. Biol. Chem. 1915, 20,

415 ; BZ 1915, 18, 157.426. D. Q. M. DICKENSON. Bull. Trop. Dis. 1915, 6, 146 ; BZ 1916,

18, 659.427. K. KAWASHINA. Bull. Trop. Dis. 1915, 6, 146; BZ 1916,

18, 659.428. J. F. SILER, P. E. GARRISON and W. J. MCNEAL. II. Progr.

rept. Thompson-McFadden Pellagra Comm. New York 1915.429. P. RAIMONO. Pathologica 1915, 7, 158.430. R. R. WILLIAMS and J. A. JOHNSTON. Philipp. Journ. of

Science 1915, 10, B, 337.431. E. V. MCCOLLXJM and M. DAVIS. Journ. Biol. Chem. 1915, 20.

641 ; BZ 1917, 19, 69.432. G. D. BUCKNER, E. H. NOLLAU and J. H. CASTLE, Amer.

Journ. Physiol. 1915, 39, 162; BZ 1918, 19, 691.433. L. J. HENDERSON and W. W. PALMER. Journ. Biol. Chem.

1915, 21, 37; B Z *9i5> l8> 326.434. B. W. PALMER and L. J. HENDERSON. Journ. Biol. Chem.

1915, 21, S7; B Z *9i5, 18, 326.435. T. B. OSBORNE and A. J. WAKEMAN. Journ. Biol. Chem. 1915,

2X, 91.436. E. V. MCCOLLTJM and M. DAVIS. Journ. Biol. Chem. 1915, 21,

179 ; BZ 1915, 18, 313.437. D. D. VAN SLYKE, G. E. CULLEN and E. STILLMAN. Proc. Soc.

Exper. Biol. New York 1915, 12, 165 ; BZ 1915, 18, 338.

352 VITAMINS

438. D. D. VAN SLYKE, G. E. CULLEN and E. STILLHAN. Proc. Soc.Exper. Biol. New York 1915, 12, 184; BZ 1915, 18, 338.

439. K. RUHL. Dermatol. Woche 1915, 60, 176; BZ 1915, 18, 13.440. E. V. MCCOLLTJM andM. DAVIS. Jonrn. Biol. Chem. 1915, 21,

615 ; BZ 1916, 18, 497.441. H. FRASER and A. T. STANTON. Lancet 1915, I, 1021; BZ

1916, i8, 659.442. J. J. NITZESCU. Soc. bid. 1915, 78, 222; B2 1916, 18, 496.443. R. WHEELER. Journ. Exper. Zool. 1915, 15, 209.444. T. B. OSBORNE and L. B. MENDEL. Journ. Biol. Chenu 1915,

22, 241.445. C. FUNK. Biochem. Bull. 1915, 4, 304.446. E. CLARK. Journ. Biol. Chem. 1915, 22, 485 ; C 1916, 87,1, ^23,447. A. BEGUN, R. HERRMANN and E. MUN2ER. Biochem. Zsclir.

1915, 71, 255 ; BZ 1915, 18, 421.448. H. ARON. Monatschr. Kinderheilk. 1915, 13, 359; BZ 1915,

18, 253.449. A. MORGEN and C. BEGER. Zschr. physiol. Chem. 1915, 94,

325 ; BZ 1915, 18, 419.450. S. BAGUONI. Atti d. Real accad. d. lincei Honia 1915 (5),

24, I, 1158; BZ 1918, 19, 621.451. Attid. Real, accad. lincei d. Roma 1915, (5), 24, II, 213,

254 ; BZ 1918, 19, 621.452. E. ABDERHALDEN. Zsclir. physiol. Chem. 1915, 96, r ; BZ

1917, 195 21.453. E. V. MCCOLLTJM and M. Davis. Journ. biol. Chem. 1915, 23,

181 ; BZ 1916, 18, 797.454. Journ. Biol. Chem. 1915, 23, 231; BZ 1916, 18, 797-455- Journ. Biol. Chem. 1915, 23, 247; BZ 1916, 18, 798.456. L. S. PALMER. Joiirn. Biol. Chem. 1915, 23, 261.457. W. P. CHAMBERLAIN. Journ. Amer. Med. Assoc. 1915, 64, 1215.458. L. B. MENDEL. Journ. Arner.Med. A.ssoc. 1915, 64, 1539.459. E. FREISE, M. GOLDSCHMIDT and A. FRANK. Monatsch.

Kinderheilk. 1915, 13, 424 ; BZ 1915, 18, 380.460. HEUBisrER. Arch, exper. Patlol. Pharmakol. 1915, 78, 22.461. G. M. ROMMEL and E. B. VEDDER. Journ. Agricult Res. 1915,

5, 489; BZ 1918, 19, 552.462. T. RUMPEL and A. W. KNACK. D. rned. Wschr. 1915, 46, 1412,463. G. VOLPINO and E. P. BORDONI. Pathologica 1915, 5, 602.464. C. FUNK and A. B. MA.CALLTJM. Journ. Biol. Chem. 1915, 23*

413 ; BZ 1916, 18, 695.465. T. B. OSBORNE and L. B. MENDEL. Journ. Biol. Chem. 1915,

235 439; BZ 1916, r8, 687.466. L. GOLDBERGER, C. H. WARING and D. G. WILLETS. U.S.

Publ Health Repts. 1915, 30, 3117.467. E. SYDENSTRICKER. U.S. Publ. Health Hepts. 1915, 30, 3132.468. J. GOLDBERGER and O. A. WHEELER. U.S. Publ. Health

Repts. 1915* 30, 3336.

BIBLIOGRAPHY 353

469. A. F. HESS. Journ. Amer. Med. Assoc. 1915, 65, 1003.470. E. WEILL and G. MOURIQTJAND. SOC. Biol. 1915, 78, 649 ; BZ

1916, 18, 695.471. H. RAUBITSCHEK. Ergebn. allgem. Pathol. 1915, 18, I, 662;

BZ 1915, 18, 414.472. F. ROHMANN. Cber kiinstliche Eraahrung und Vitamine.

Gebr. Borntrager, Berlin, 1916. BZ 1916, 18, 741.473. C. FUNK. Biochem. Bull. 1916, 5, 1.474. E. SCHLOSS. 80 Stoffwechselversuche liber die therapeutische

Beeinflussung der rachitischen Stoffwechselstorung. S. Karger,Berlin, 1916.

475. M. X. SULLIVAN and C. VOEGTLIN. Journ. Biol. Chem. 1916,24, XVI.

476. Journ. Biol. Chem. 1916, 24, XVII.477. T. B. OSBORNE and L. B. MENDEL. Journ. Biol. Chem. 1916,

24, 37; BZ 1916, 18, 798.478. P. RAIMONO. Arch. ital. biol. 1916, 65, 1; BZ 1919, 20, 342.479. A. H. SMITH. Arch, of Ophthalmol. 1916, 45, H, 1; BZ 1917,

I9> 131-480. E. B. HART and E. V. MCCOLLUM. Journ. Biol. Chem. 1916,

24, 3 ; BZ 1917, 19, 69.481. R. R. WILLIAMS. Philipp. Journ. of Science, 1916, 11, A, 49;

BZ 1917, 19, 254.482. T. B. OSBORNE and L. B. MENDEL. Amer. Journ Physiol.

1916, 40, 16; BZ 1918, 19, 906.483. T. B. ROBERTSON and L. A. RAY. Journ. Biol. Chem. 1916,

24, 347; BZ 1917, 19, 68.484. Journ. Biol. Chem. 1916, 24, 363 ; BZ 1917, 19, 68.485. Journ. Biol. Chem. 1916, 24, 385 ; BZ 1917, 19, 68.486. Journ. Biol. Chem. 1916, 24, 397; BZ 1917, 19, 68.487. Journ. Biol. Chem 1916, 24, 409 ; BZ 1917, 19, 68.488. E. V. MCCOLLUM and C. KENNEDY. Journ. Biol. Chem. 1916,

24, 491.489. P. SUAREZ. Biochem. Zschr. 1916, 72, 17; BZ 1917, 19, 184.490. E. V. MCCOLLUM ,N. SIMMONDS and W. PITZ. Proc. Soc. Exper.

Biol. 1916, 13, 129 ; BZ 1917, 19, 253.491. A. F. HESS. Proc. Soc. Exper. Biol. 1916, 13, 145 ; BZ 1917,

195 254-492. T. B. OSBORNE and L. B. MENDEL. Journ. Biol. Chem. 1916,

25, 26; BZ 1918, 19, 549.493- P^oc. Soc. Exper. Biol. 1916, 13, 147 ; BZ 1917,

195 254-494. E. B. HART and E. V. MCCOLLUM. Proc. Amer. Soc. Biol.

1916, 28.; BZ 1917, 19, 69.495. E. WEILL and G. MOURIQUAND. SOC. Biol. 1916, 79, 37 ; BZ

1916, 18, 798.4 96. and P. MICHEL. SOC. Biol. 1916, 79, 189; BZ

1916, 18, 798.

354 VITAMINS

497. E. WEILL and G. MOURIQUAND. SOC. Biol. 1916, 79, 194 ;BZ 1916, i85 798.

498. J. C. DRUMMOND. Biochem. Journ. 1916, 10, 77 ; BZ 1918,19, 619.

499. Biochem. Journ. 1916, 10, 89; BZ 1918, 19, 619.500. L. B. MENDEL. Ergebn. Physiol. 1916, 15, 102 ; BZ 1916,

18, 784.501. D. J. LLOYD. Journ. Pathol. Bacteriol. 1916, 21, 113.502. R. B. GIBSON. Philipp. Journ. of Science 1916, u , B, 119.503. E. B. VEDDER. Arch. Internal. Med. 1916, 18, 137.504. A. F. HESS. Amer. Journ. Dis. Childr. 1916, 12, 152.505. W. H.WILLCOX. Journ. Roy. Army Med. Corps 1916, 27, 191.506. JURGENS. Berl. klin. Wschr. 1916, 18, 210.507. E. V. MCCOLLUM, N. SIMMONDS and W. PITZ. Journ. Biol.

Chem. 1916, 25, 105 ; BZ 1918, 19, 548.508. I. BANG. Biochem. Zschr. 1916, 74, 278 ; BZ 1918, 19, 550.509. D. L. MONACO. Arch, difarm. 1916, 21,121 ; BZ 1918, 19,722.510. C. FUNK. Proc. Soc. Exper. Biol. Med. 1916, 14, 9 ; BZ 1918,

19, 694.511. C. VOEGTLIN. Journ. Acad. of Science Washington 1916,6, 580*512. A. CLEMENTI. Arch, di fisiol. 1916, 14, 4 ; BZ 1918, 19, 907.513. R. R. WILLIAMS. Proc. Soc. Exper. Biol. 1916, 14, 25; BZ

1918, 19, 695.514. J. F. SILER, P. E. GARRISON and W. J. MCNEAL. Proc. Soc.

Exper. Biol. Med. 1916, 14, 28; BZ 1918, 19, 695.515. E. B. HART, W. S. MILLER and E. V. MCCOLLUM. Journ. Biol.

Chem. 1916, 25, 239; BZ 1918, 19, 619.516. C. EIJKMAN. Arch, exper. Pathol. 1916, 222, 301; BZ 1917.

19, n o .517. W. STEPP. Zschr. Biol. 1916, 66, 339; BZ 1917, 19, 20.518. J. GOLDBERGER. Journ. Amer. Med. Assoc. 1916, 66, 471.519. W. STEPP. Zschr. Biol. 1916, 66, 350.520. Zschr. Biol. 1916, 66, 365.521. A. HUNTER, M. A. GIVENS and R. C. LEWIS. U.S. Publ.

Health Service Hyg. Lab. Bull. 1916, 102, 39.522. F. ROHMANN. Chemie der Zerealien. Ferd. Enke, Stuttgart,

1916; BZ 1917, 19, 67.523. T. RUMPEL. Berl. klin. Wschr. 1916, 18, 480.524. A. E. RICHARDSON and H. S. GREEN. Journ. Biol. Chem. 1916,

25, 317; BZ 1918, 19, 547.525. A. URBEANU. Die Gefahr einer an Kaliumverbindungen zu

armen Ernahrungsweise und ihre Beziehungen zu Ernah-rungskrankheiten. Urban & Schwarzenberg, Berlin u.Wien, 1916.

526. W. STEPP. Zschr. Biol. 1916, 66, 365 ; BZ 1918, 19, 398.527. C. FUNK. Journ. biol. chem. 1916, 25, 409 ; BZ 1918, 19, 551.528. R. R. WILLIAMS. Journ. Biol. Chem. 1916, 25, 437 ; BZ 1918,

19* 55*-

BIBLIOGRAPHY 355

529. A. CLEMENTI. Arch, di farm. 1916, 21, 441 ; BZ 1918, 19, 695.530. H. WINTZ. Miinchn. med. Wschr. 1916, 445; BZ 1916 18, 798.531. C. ASAYAMA. Biochem. Journ. 1916, 10, 466; BZ 1918,

195 693.532. T. B. OSBORNE and L. B. MENDEL. Biochem. Journ. 1916

10, 534; BZ 1918, 19, 619.533. P. HEIM. Monatschr. Kinderheilk. 1916, 13, 495; BZ 1916,

18, 798.534- J- w - JOBLING and W. PETERSEN. Journ. Infect Dis. 1916,

18, 501; BZ 1917, 19, no .535. H. ACKROYD and F. G. HOPKINS. Biochem. Journ. 1916, 10,

551 ; BZ 1918, 19, 621.536. C. VOEGTLIN. Journ. Acad. of Science Washington 1916, 6,

575 ; BZ 1918, 19, 829.537. A. SEIDELL. U.S. Public Health Rept. 1916, 31, 364.538. B. T. ROBERTSON and E. CUTLER. Journ. Biol. Chem. 1916,

25> 635; BZ 1918, 19, 550.539. Journ. Biol. Chem. 1916, 25, 647 ; C 1917, 88,1, 330.540. Journ. Biol. Chem. 1916, 25, 663 ; BZ 1918, 19, 550.541. T. B. OSBORNE and L. B. MENDEL. Journ. Biol. Chem. 1916,

26, 1 ; BZ 1918, 19, 400.542. M. L. KOCH and C. VOEGTLIN. U.S. Publ. Health Service Hyg.

Lab. Bull. 1916, 103, 51.543. U.S. Publ. Health Service Hyg. Lab. Bull. 1916,

103, 5*•544. W. B. BOTTOMLEY. Proc. Roy. Soc. London 1916, 88, B, 237.545. R. R. WILLIAMS. Amer. Med. 1916, 11, 756.546. M. STARK. Amer. Med. 1916, n , 762.547. W. J. MCNEAL. Journ. Amer. Med. Assoc. 1916, 66, 975.548. B. T. ROBERTSON. Journ. Amer. Med. Assoc. 1916, 66, 1009;

BZ 1919, 20, 237.549. H. H. MITCHELL. Journ. Biol. Chem. 1916, 26, 231; BZ

1918, 19, 619.550. T. B. OSBORNE and L. B. MENDEL. Journ. Biol. Chem. 1916,

26, 293; BZ 1918, 19, 400, 549.551. E. V. MCCOLLUM, 2SF. SIMMONDS and W. PITZ. Amer. Journ.

Physiol. 1916, 41, 333; BZ 1918, 19, 907.552. E. V. MCCOLLUM, N. SIMMONDS and W. PITZ. Amer. Journ.

Physiol. 1916, 41, 361.553. C. EIJKMAN and C. J. C. VAN HOOGENHUYGE. Verh. K. akad.

Wetensch. Amsterdam 1916, 18, 1467.554. C. FUNK. Journ. biol. chem. 1916, 27, 1.555. und j . POKLOP. Journ. Biol. Chem. 1916, 27, 1.556. C. A. WELLS und P. W. EWING. Journ. biol. chem. 1916,

557. L. S. PALMER. Journ. Biol. Chem. 1916, 27, 27.558. W. B. BOTTOMLEY. Proc. Roy. Soc. London 1916, 89, 102.559. A. W. KNACK. Zentralbl. inn. Med. 1916, $j, 753.

356 VITAMINS

560. R. R. WILLIAMS and A. SEIDELL. Journ. Biol. Chem. 1916,26, 431; BZ 1918, 19, 551.

561. E. V. MCCOLLUM, N. SIMMONDS and W. PITZ. Journ. Biol.Chem. 1916, 27, 33 ; BZ 1918, 19, 692.

562. C. FUNK and A. B. MACALLUM. Journ. Biol. Chem. 1916, 27,51; BZ 1918, 19, 694.

563. Journ. Biol. Chem. 1916, 27, 63 ; BZ 1918, 19, 694.564. W. H. EDDY. Journ. Biol. Chem. 1916, 27, 113; BZ 1918,

I9> 55°-565. F. P. UNDERHILL. Journ. Biol. Chem. 1916, 27,127; BZ 1918,

19, 469. /566. Journ. Biol. Chem. 1916, 27, 161 ; BZ 1918, 19, 470.567. C. FUNK, W. G. LYLE and D. MCCASKEY. Journ. Biol. Chem.

1916, 27, 173 ; BZ 1918, 19, 694.568. A. G. HOGAN. Journ. Biol. Chem. 1916, 2J9 193 ; BZ 1918,

19, 547-569. J. LOEB and J. H. NORTHROP. Journ. Biol. Chem. 1916, 27,

309; BZ 1918, 19, 686.570. C. VOEGTLIN and G. F. WHITE. Journ. of Pharm. 1916, 9, 155 ;

BZ 1918, 19, 344-571. T. RUMPEL and A. W. KNACK. D. med. Wschr. 1916, 47, 4440.572. J. I. DURAND. Journ. Amer. Med. Assoc. 1916, 67, 564.573. E. B. VEDDER. Journ. Amer. Med. Assoc. 1916, 67, 1494.574. T. B. OSBORNE and A. J. WAKEMAN. Journ. Biol. Chem.

1916, 28, 1.575. L. JACKSON and J. J. MOORE. Journ. Infect. Dis. 1916, 19, 478.576. and A. M. MOODY. Journ. Infect. Dis. 1916, 19, 511.577. H. B. LEWIS and W. G. KARR. Journ. Biol. Chem. 1916, 28,

15; BZ 1918, 19, 398.578. E. V. MCCOLLUM, N. SIMMONDS and W. PITZ. Journ. Biol.

Chem. 1916, 28, 153 ; BZ 1918, 19, 692.579. Journ. Biol. Chem. 1916, 28, 211 ; BZ 1918

I9> 693.580. J. GOLDBERGER. U.S. Publ. Health Repts. 1916, 31, 3159.581. A. HOLST and T. FRSLICH. Norsk, mag. f. lagevidensk. 1916,

77, 1008.582. J. J. MOORE and L. JACKSON. Journ. Amer. Med. Assoc. 1916,

67, 1931.583. E. SCHLOSS. Berl. klin. Wschr. 1916, Nr. 5, 27, 50, 51 and 52.584. Ergebn. inn. Med. Kinderheilk. 1917, 15, 55.585. L. B. MENDEL. Amer. Journ. Med. Science 1917, 153, 1.586. C. SCHEARER. Lancet 1917, I, 59.587. O. ROSENHEIM. Biochem. Journ. 1917, 11, 7.588. M. P. MENDOZA-GUAZON. Philipp. Journ. of Science 1917, 12,

B, 51.589. W. B. BOTTOMLEY. Proc. Roy. Soc. London 1917, 89, B, 481.590. F. A. MOCKERIDGE. Proc. Roy. Soc. London 1917, 89, B, 508.591. A. F. HESS. Amer. Journ. Dis. Childr. 1917, 13, 98.

BIBLIOGRAPHY 357

592. E. B. HART, E. V. MCCOLLUM, H. STEENBOCK and G. C.HUMPHREY. Journ. Agric. Res. 1917, 10, 175.

593. H. CHICK and E. M. HUME. Journ. Roy. Army Med. Corps1917, 29, 121.

594. Transact. Soc. Trop. Med. Hyg. 1917, 10, 179.595- Proc. Royal Soc. London 1917, 90, B, 44 ; BZ 1919,

21, 313; C 1919, 90, I, 118.596. Proc. Roy. Soc. London 1917, 90, B, 60; BZ 1919,

21, 313; C 1919, 90, I, 119.597. A. W. BOSWORTH and H. J. BOWDITCH. Journ. Biol. Chem.

1917, 28, 431 ; BZ 1918, 19, 695.598. E. V. MCCOLLUM, 1ST. SLMMONDS and W. PITZ. Journ. Biol.

Chem. 1917, 28, 483 ; BZ 1918, 19, 693.599. R. H. CHITTENDEN and F. P. UNDERHILL. Amer. Journ.

Physiol. 1917, 44, 13 ; BZ 1919, 21, 314.600. G. TOTANI. Biochem. Journ. 1917, 10, 382 ; BZ 1918, 19, 828.601. W. H. EDDY and J. C. ROPER. Amer. Journ. Dis. Childr.

1917, 14, 189.602. A. F. HESS. Amer. Journ. Dis. Childr. 1917, 14, 337.603. Journ. Amer. Med. Assoc. 1917, 68, 235.604. E. WEILL and G. MOURIQUAND. SOC. Biol. 1917, 78, 649.605. W. H. EDDY. Journ. Biol. Chem. 1917, 29, XVL606. E. V. MCCOLLUM, N. SIMMONDS and H. STEENBOCK. Journ.

Biol. Chem. 1917, 29, XXVI.607. H. STEENBOCK. Journ. Biol. Chem. 1917, 29, XXVII.608. E. V. MCCOLLUM. Journ. Amer. Med. Assoc. 1917, 68, 1379.609. C. E. BLOCH. Ugeskr. 1 Lager 1917, 79, 300, 349.610. Journ. Amer. Med. Assoc. 1917, 68, 1516.611. C. P. HOWARD and T. INGVALDSEN. Bull. John Hopkins

Hosp. 1917, 28, 222.612. E. B. HART, J. G. HALPIN and E. V. MCCOLLUM. Journ. Biol.

Chem. 1917, 29, 57; BZ 1919, 20, 23.613. T. B. OSBORNE and L. B. MENDEL. Journ. Biol. Chem. 1917,

29, 69; BZ 1919, 20, 23.614. R. BERG. Zschr. D. Landwirtschaftsrates 1917, 15, 148.615. G. CHRISTMANN. Ernahrg. d. Pflanze 1917, 13, 81; BZ 1918,

19, 468.616. A. SEIDELL. Journ. Biol. Chem. 1917,29,145; BZ 1919,20,105.617. A. HARDEN and S. S. ZILVA. Biochem. Journ. 1917, 11, 172;

BZ 1919, 20, 105.618. W. D. HALLIBURTON and J. C. DRUMMOND. Journ. of Physiol.

1917, 51, 234; BZ 1919, 20, 238.619. J. C. DRUMMOND. Biochem. Journ. 1917, 11, 255; BZ 1919,

20, 409.620. E. V. MCCOLLUM. Ann. Amer. Acad. Polit. Social Science

1917, 74* 95-621. J. F. SILER, P. E. GARRISON and W. J. MCNEAL. III. Rept.

Rob. M. Thompson Pellagra Comm., etc., New York, 1917.

358 VITAMINS

622. T. B. OSBORNE and L. B. MENDEL. Journ. Biol. Chem. 1917,29, 289.

623. C. ROSE. Mimclin. med. Wschr. 1917, 6y, 312.624. D. J. DAVIS. Journ. Infect. Dis. 1917, 21, 392.625. E. Y. MCCOLLUM, N. SIMMONDS and W. Pixz. Journ. Biol.

Chem. 1917, 29, 341 ; BZ 1919, 20, 104.626. D. J. HULSHOFF-POL. Arch. ScMffs- u. Trop.-Hyg. 1917, 21,

366; BZ 1918, 19, 829627. E. WEILL and G. MOTTRIQTJANTD. SOC. Biol. 1917, 79, 372;

BZ 1918, 19, 828.628. TJ. CAZZANTI. Boll. chim. farm. 1917, 56, 397; C 1919,90,1, 674.629. G. CORNAXBA. Boll. cMm. farm. 1917, 56, 577 ; C 1919* 90

I, 674.630. W. FAXTA and M. QUITTNER. Wieix. klin. Wschr. 1917, Nr.

38 ; BZ 1918, 19, 720.631. D. J. HUXSHQFF-POL. Journ. of Physiol. 1917, 51, 432 ; BZ

1919, i9> 829 ; 20, 237.632. F. UHLMANN. Korr.-BL Schweiz. Aizte 1917, 47, 464 ; BZ

1918, 19, 796.633. A. GURBER. Munchn. med. Wschr. 1917, 64, 707; BZ 1918,

195 547-634- A. G. HOGAN. Journ. Biol Chem. 1917, 29, 485 ; BZ 1919,

20, 22.635. R. R. WILLIAMS. Joum. Biol. Ckem. 1917, 29, 495 ; BZ 1919,

20, 24.636. E. V. MCCOLLUM, N". SIMMONDS and W. PITZ. Journ. Biol.

Chem. 1917, 29, 521; BZ 1919, 20, 23.637. B. NOCHT. D. med. Vschi. 1917, 48, July.638. W. G. KARR and H. E. LKWIS. Amer. Journ. PhysioL 1917,

44, 5S5; BZ 1920, 22, 358.639. A. W. KNACK and NEUMANN. D. med. Wschr. 1917, 48, 901 ;

BZ 1918, 19, 719.640. BOLDYREFF. Soc. Biol. 1917, 80, 911 ; BZ 1919, 20, 410.641. M. F. MAIGNONT. C. r. 1917, 166, 919 ; B2 1919, 20, 239.642. C. r. 1917, 166, 1008 ; BZ 1919, 20, 239.€43. L. BATJMANN and C. P. HOWARD. Ainer. Joura. Med. Science

1917, I535 650.€44. W. H. WILLCOX. Lancet 1917, II, 677.645. E. V. MCCOLXUM, N. SIMJMONTDS aad W. Pirz. Journ. biol.

Chem. 1917, 30, 13 ; BZ 1919, 20, 104.646. A. G. HOGAN. Journ. Biol. Chem. 1917, 30, 115; BZ 1919,

29, 103.647. J. H. NORTHROP. Journ. Biol. Chem. 1917, 30, 181 ; B

1919, 20, 105.648. A. E. RICHARDSON and H. S. GREEN. Journ. Biol. Chem. 191 y>

30, 243; BZ 1919, 20, 104.649. T. B. OSBORNTE, L. B. MJENDEL, E. L. PERR^ and A. J. WAKE-

MAN. Joum. Biol. Chem. 1917, 31, 149 ; BZ 1919, 20, 237.

BIBLIOGRAPHY 359

650. E. M. K. GEILING. Journ. Biol. Chem. 1917, 31, 173 ; BZ1919, 20, 239.

651. E. V. MCCOLLUM and W. PITZ. Journ. Biol. Chem. 1917, 31,229; BZ 1919, 20, 236.

652. Journ. Biol. Chem. 1917, 31, 341 ; BZ 1919, 20, 236.653. H. LEWIS. Journ. Biol. Chem. 1917, 31,363 ; C 1921, 92,1, 636.654. A. E. RICHARDSON and H. S. GREEN. Journ. Biol. Chem. 1917,

31, 379; BZ 1919, 20, 238.655. E. B. HART, J. G. HALPIN and H. STEENBOCK. Journ. Biol.

Chern. 1917, 31, 415 ; BZ 1919, 20, 238; C 1921, 92, I, 637.656. and B. SURE. Journ. Biol. Chem. 1917, 31, 445 ;

C 1921, 92, I, 637.657. T. B. ROBERTSON and M. DELPRAT. Journ. Biol. Chem. 1917,

31, 567; C 1921, 92, I, 638.658. E. V. MCCOLLUM and N. SIMMONDS. Journ. Biol. Chem. 1917,

32, 29; BZ 1919, 20, 343.659. A. L. DANIELS and N. B. NICHOLS. Journ. Biol. Chem. 1917,

32, 91; BZ 1919, 20, 341.660. J. H. NORTHROP. Journ. Biol. Chem. 1917, 32, 133 ; C 1921,

92, I, 637.661. E. V. MCCOLLUM and N. SIMMONDS. Journ. Biol. Chem. 1917,

32, 181 ; BZ 1919, 20, 344.662. W. A. WITHERS and F. E. CARRUTH. Journ. Biol. Chem. 1917,

32, 245 ; C 1921, 92, I, 688.663. T. B. OSBORNE. L. B. MENDEL, E. L. FERRY and A. J. WAKE-

MAN. Journ. Biol. Chem. 1917, 32, 309; BZ 1919, 20, 341.664. E. V. MCCOLLUM and N. SIMMONDS. Journ. Biol. Chem. 1917,

32, 347; BZ 1919, 20, 344.665. T. B. OSBORNE, L. B. MENDEL, E. L. FERRY and A. J. WAKE-

MAN. Journ. Biol. Chem. 1917, 32, 369; BZ 1919, 20, 342.666. A. D. EMMET and L. H. MCKIM. Journ. Biol. Chem. 1917, 32,

409 ; BZ 1919, 20, 342.667. J. T. LEARY and S. H. SHEIB. Journ. Amer. Chem. Soc. 1917,

39, 1066 ; BZ 1918, 19, 696.668. V. BABES. Bull. Sect. Scient. Acad. Roumaine 1917, 5, 151 ;

C 1921, 92, I, 62.669. Bull. Sect. Scient. Acad. Roumaine 1917, 5,159 ; C 1921

92, I, 63.670. E. V. MCCOLLUM and N. SIMMONDS. Journ. Biol. Chem. 1917,

33, 55 ; BZ 1919, 20, 342.671. E. WEILL and G. MOURIQUAND. SOC. Biol. 1917, 80, 372.672. Experimental Scurvy, an Historical Note. Journ. Amer.

Med. Assoc. 1917, 69, 2045.673. E. D. W. GREIG. Ind. Journ. Med. Res. 1917, 4, 818.674. L. M. SMITH and H. B. LEWIS. Journ. Amer. Chem. Soc. 1917,

39, 2231.675. M. SAWYER, L. BAUMANN and F. STEVENS. Journ. Biol.

Chem. 1918, 33, 103.

360 VITAMINS

676. ELIAS. Zschr. exper. Med. 1918, 1, 1.677. H. CHICK, E. M. HUME and R. F. SKELTON. Lancet 1918,1, 1.678. A. F. HESS and L. J. UNGER. Proc. Soc. Exper. Biol. Med.

1918, 16, 1.679. E. V. MCCOLLUM. The Newer Knowledge of Nutrition.

Macmillan Comp., New York, 1918.680. A. G. HOGAN. Journ. Biol. Chem. 1917, 33, 151 ; BZ 1919,

20, 339.681. A. L. DANIELS and R. LOUGHLIN. Journ. Biol. Chem. 1917,

33, 295 ; BZ 1917, 20, 340; C 1919, 90, I, 560.682. E. V. MCCOLLUM and N. SIMMONDS. Journ. Biol. Chem. 1918,

335 3O3 ; BZ 1919, 20, 344; C 1919, 20, I, 41.683. E. ABDERHALDEN and G. EWALD. Zschr. exper. Med. 1918,

5, 1; BZ 1918, 19, 551.684. W. H. JANSEN. Miinchn. med. Wschr. 1918, 65, 10 ; BZ 1918,

20, 26.685. H. S. HUTCHISON. Glasgow Med. Journ. 1918, 93, 8.686. A. F. HESS and J. KILLIAN. Proc. Soc. Exper. Med. Biol.

1918, 16, 43.687. J. C. DRUMMOND. Biochem. Journ. 1918, 12, 25 ; BZ 1919,

20, 409.688. A. HARDEN and S. S. ZILVA. Biochem. Journ. 1918, 12, 93 ;

BZ 1919, 20, 411.689. H. CHICK, E. M. HUME and R. F. SKELTON. Biochem. Journ.

1918, 12, 131; BZ 1919, 20, 411.690. J. C. DRUMMOND. Journ. of Physiol. 1918, 52, 95 ; BZ 1919,

20, 341.691. E. V. MCCOLLUM, N. SIMMONDS and H. T. PARSONS. Journ.

Biol. Chem. 1918, 33,411 ; BZ 1919, 20, 344 ; C1919, 90,1,41.692. T. B. OSBORNE and L. B. MENDEL. Journ. Biol. Chem. 1918,

33, 433 ; BZ 1919, 20, 339.693. W. PITZ. Journ. Biol. Chem. 1918, 33, 471; BZ 1919, 20, 345 ;

C 1919, 90, I, 42.694. H. STEENBOCK. Science Monthly 1918, 7, 179.695. L. JACKSON. Journ. Infect. Dis. 1918, 22, 457.696. L. B. BULL. Joum. compar. Pathol. Therap. 1918, 31, 193.697. F. M. R. WALSHE. Brit. Journ. Childr. Dis. 1918, 15, 258.698. Quart. Journ. Med. 1918, 11, 320.699. R. L. M. WALLIS. Ind. Journ. Med. Res. 1918, 6, 45.700. E. D. W. GREIG and D. F. CURJEL. Ind. Journ. Med. Res. 1918,

6, 56.701. A. HARDEN and S. S. ZILVA. Journ. Inst. Brewing 1918,

24, 197.702. T. B. OSBORNE and L. B. MENDEL. Journ. Biol. Chem. 1918,

34, 17; BZ 1919, 20, 407.703. A. J. P. PACINI and D. W. RUSSEL. Journ. Biol. Chem. 1918,

34, 43 ; BZ 1919, 20, 412.704. A. HARDEN and S. S. ZILVA. Lancet 1918, II, 320.

BIBLIOGRAPHY 361

705. E. D. W. GREIG. Ind. Journ. Med. Res. 1918, 6, 143.706. D. J. DAVIS. Journ. Infect. Dis. 1918, 23, 248.707. J. C. DRUMMOND. Lancet 1918, II, 482.708. H. W. DYKE. Lancet 1918, II, 513.709. E. V. MCCOLLUM. Amer. Journ. Publ. Health 1918, 8, 191.710. C. A. STEWART. Journ. Exper. Zool. 1918, 25, 301.711. H. CHICK, E . M . H U M E and R.E. SKELTON. Lancet 1918, II, 735.712. M. MELLANBY. Lancet 1918, II, 767.713. H. CHICK and M. RHODES. Lancet 1918, II, 774.714. W. RAMSDEN. Journ. Soc. Chem. Ind. 1918, 37, T, 53 ; C

1919, 90, I, 566.715. H. B. THOMPSON and L. B. MENDEL. Amer. Journ. Physiol.

1918, 45, 431 ; BZ 1920, 22, 408.716. J. FEIGL. Biochem. Zschr. 1918, 85, 365 ; BZ 1919, 20, 34.717. E. B. VEDDER. Journ. of Hyg. 1918, 17,1 ; BZ 1919, 20, 237.718. A. HOLST. Zentralbl. Bakteriol. 1918, 81, 56 ; BZ 1919, 20, 24.719. T. B. OSBORNE. L. B. MENDEL, E. L. FERRY and A. J. WAKE-

MAN. Journ. Biol. Chem. 1918, 34, 131 ; BZ 1919, 20, 406.720. H. C. SHERMAN, L. WHEELER and A. B. YATES. Journ. Biol.

Chem. 1918, 34, 383 ; BZ 1919, 20, 407.721. C. O. APPLEMAN. Science 1918, 48, 319.722. A. EPSTEIN. Jahrb. Kinderheilk. 1918, 88, 237.723. A. VISWALINGAM. Journ. Trop. Med. Hyg. 1918, 21, 153.724. F. J. H. COUTTS. Rept. Local Govt. Board Publ. Health, etc.,

1918, N. Ser. Nr. 116, 1.725. G. WINFIELD. Rept. Local Govt. Board Publ. Health, etc.,

1918, N. Ser. Nr. 116, 139.726. J. J. MOORE. Proc. Inst. Med. Chicago 1918, 254.727. V. STEFANSSON. Med. Rev. of Rev. 1918, 24, 257.728. ARNETHS. D. med. Wschr. 1918, 45, 509.729. G. H. WHIPPLE and D. D. VAN SLYKE. Journ. Exper. Med.,

1918, 28, 213 ; BZ 1919, 20, 241.730. L. LANGSTEIN and F. EDELSTEIN. Zschr. Kinderheilk. 1918,

16, 305 ; BZ 1919, 20, 103.731. E. WEILL and G. MOURIQUAND. SOC. Biol. 1918, 81, 432;

C 1919, 90, I, 385.732. H. BIERRY and P. PORTIER. SOC. Biol. 1918, 81, 574 ; BZ

1919, 21, 16.733. DUBOIS. Soc. Biol. 1918, 81, 604 ; BZ 1919, 21, 16.734. E. WEILL, G. MOURIQUAND and PE*RONNET. SOC. Biol. 1918,

81, 607 ; C 1919, 90, I, 391.735. Soc. Biol. 1918, 81, 678 ; BZ 1919, 21, 137.736. T. B. OSBORNE, L. B. MENDEL, E. L. FERRY and A. J. WAKE-

MAN. Journ. Biol. Chem. 1918, 34, 521 ; BZ 1919, 20, 407.737- Journ. Biol. Chem. 1918, 34, 537 ; BZ

1919, 20, 407 ; C 1919, 90, I, 391.738. W. D. HALLIBURTON. Arch. Neerland physiol. 1918, 2, 602 ;

BZ 1919, 20, 238.

362 VITAMINS

739. T. B. OSBORNE and L. B. MENDEL. Journ. Biol. Chem. 1918,35, 19; BZ 1919, 20, 405 ; C 1919, 90, I, 316.

740. H. STEENBOCK, H. E. KENT and E. G. GROSS. Journ. Biol.Chem. 1918, zs, 61 ; BZ 1919, 20, 408 ; C 1919, 90, I, 391.

741. G. Rossi. Arch, fisiol. 1918, 16, 125 ; BZ 1919, 21, 137.742. A. HIRSCH und E. MORO. Jahrb. Kinderheilk. 1918, 88, 513 ;

BZ 1919, 20, 243.743. M. E. MAIGNON. C. r. 1918, 167, 91 ; BZ 1919, 20, 408.744. C.r. 1918,167,174; BZ1919, 20,408 ; C1918, 89,11, 1053.745. TANJI. D. Arch. klin. Med. 1918, 116,746. H. C. SHERMAN and J. C. WINTERS. Journ. Biol. Chem. 1918,

35, 301; BZ 1919, 20, 408.747. C. EIJKMAN, Pharm Weekbl. 1918, 55, 765 ; C 1919, 90,1., 487.748. H. B. MCCLUGAGE and L. B. MENDEL. Journ. Biol. Chem.

1918, 35, 353; BZ 1919, 20, 406.749. B. COHEN and L. B. MENDEL. Journ. Biol. Chem. 1918, 35

425; BZ 1919, 20, 411; C 1919, 90, I, 392.750. A. F. HESS and L. J. UNGER. Journ. Biol. Chem. 1918, 35,

479; BZ 1919, 20, 410; C 1919, 90, I, 392.751. Journ. Biol. Chem. 1918, 35, 487 ; BZ 1919, 20,

410; C 1919, 90, I, 392.752. H. STEENBOCK, P. W. BOUTWELL and H. E KENT. Journ.

Biol. Chem. 1918, 35,517; BZ 1919, 20, 409; C 1919* 9°>I, 393-

753. A. DUTCHER and F. A. COLLATZ. Journ. Biol. Chem. 1918, 36,63 ; BZ 1919, 20, 409.

754. M. H. GIVENS and B. COHEN. Journ. Biol. Chem. 1918, 36,127; BZ 1919, 20, 480; C 1919, 90, I, 487.

755. F. UHLMANN. Zschr. Biol. 1918, 68, 419; BZ 1919, 20, 105.756. E. WEILL and G. MOURIQUAND. Journ. Physiol.-pathol. 1918,

17, 849; BZ 1919, 20, 237.757. A. F. HESS and L. J. UNGER. Journ. Amer. Med. Assoc. 1918,

70, 900.758. Proc. Soc. Exper. Biol. Med. 1918, 15, 141.759. H. H. GREEN. South Africa Journ. Science 1918, 14, 483.760. South Africa Journ. Science 1918, 14, 519.761. E. V. MCCOLLUM and N". SIMMONDS. Amer. Journ. PhysioL

1918, 46, 275.762. C. E. BLOCH. Uges kr. f. Lager 1918, 80, 815, 868.763. Journ. Amer. Med. Assoc. 1918, 71, 322, 416.764. J. GOLDBERGER. U.S. Publ. Health Repts. 1918, 33, 481.765. H. H. GREEN. Repts. Dir. Vet. Res. Union S. Africa 1918,

5/6, 753-766. H. H. GREEN. Repts. Dir. Vet. Res. Union S. Africa 1918,

5/6, 777-767. A. T. HESS. Journ. Amer. Med. Assoc. 1918, 71, 941.768. J. GOLDBERGER, G. A. WHEELER and E. SYDENSTRICKER.

Journ. Amer. Med. Assoc. 1918, 71, 944.

BIBLIOGRAPHY 363

769. C. VOEGTLIN, G. C. LAKE and C. N. MYERS. U.S. Publ. HealthRepts. 1918, 33, 647.

770. C. VOEGTLIN and C. N. MYERS. U.S. Publ. Health Repts.1918, 33, 843.

771- U.S. Publ. Health Repts. 1918, 33, 911.772. H. BORUTTAU. Biochem. Zschr. 1918, 88,96; BZ 1918, 9, 691.773- Biochem. Zschr. 1918, 88, 103; BZ 1918, 19, 691.774. Biochem. Zschr. 1918, 88, 420; BZ 1919, 20, 23.JJ5. K. SUGIURA and S. R. BENEDICT. Journ. Biol. Chem. 1918,

36, 171 ; BZ 1919, 20, 479; C 1919, 90, I, 488.776. Journ. Biol. Chem. 1918, 36, 191 ; BZ 1919, 20, 480 ;

C 1919, 90, I, 488.777. E. V. MCCOLLUM, N. SIMMONDS and H. T. PARSONS. Journ.

Biol. Chem. 1918, 36, 197; BZ 1919, 20, 477 ; C 1919, 9a,I, 488.

778. M. E. MAIGNON. C. r. 1918, 167, 218 ; BZ 1919, 20, 408 ;C 1918, 89, II, 1053.

779. M. J. AMAR. C. r. 1918, 167, 241 ; BZ 1919, 20, 408.780. L. LANGSTON and F. EDELSTEIN. Zschr. Kinderheilk. 1918,

I7> 255 ; BZ 1919, 20, 103.781. H. ARON. Berl. klin. Wschr. 1918, S. 546 ; BZ 1919, 20, 102.782. L. BRUNTZ and L. SPILLMAN. SOC. Biol. 1918, 81, 1243 ; BZ

1919, 21, 16.783. E. WEILL and G. MOURIQTJAND. SOC. Biol. 1918, 81, 1253 ;

BZ 1919, 21, 16.784. M. C. DENTON and E. KOHMAN. Journ. Biol. Chem. 1918, 36,

249; BZ 1919, 20, 480.785. C. ROSE and R. BERG. Munchn. med. Wschr. 1918, 65, 1011.786. W. PITZ. Journ. Biol. Chem. 1918, 36, 439 ; BZ 1919, 20, 411.787. I. BANG. Biochem. Zschr. 1918, 91, n o .788. D. N. PATON, L. FINDLAY and A. WATSON. Brit. Med. Journ.

1918, II, 625.789. AGULHON and LEGROUX. C. r. 1918, 167, 597.790. H. W. WILTSHIRE. Lancet, 1918, II, 811.791. A. H. SMITH. Lancet 1918, II, 813.792. A. W. MCCANN. The Science of Eating. New York, 1918.793. A. SLATOR. Biochem. Journ. 1918, 12, 248.794. A. HARDEN and S. S. ZILVA. Biochem. Journ. 1918, 12, 259;

BZ 1919, 20, 412; C 1919, 90, I, 391.795. Biochem. Journ. 1918, 12, 270; BZ 1919. 20, 412;

C 1919, 9<>5 I» 392.796. C. EIJKMAN and D. J. HULSHOFF-POL. K. Akad. Wet. Amster-

dam 1918, 26, 1466; BZ 1919, 20, 102.797. A. DUTCHER and F. A. COIXATZ. Journ. Biol. Chem. 1918, 36,

547; BZ 1919, 20> 4!9-798. Journ. Biol. Chem. 1918, 36, 551; BZ 1919, 20, 410.799. R. HIFT. Wien. klin. Wschr. 1918, 31, 939.800. E. MULLER. Berl. klin. Wschr. 1918,65, 1024; C 1919,90,1.189-

364 VITAMINS

801. A. LIPSCHUTZ. Sitz.-Ber. Naturf.-Ges. Bern 1918, S. 29; BZ1920, 22, 94.

802. A. M. MUCKENFUSS. Journ. Amer. Chem. Soc. 1918, 41,1606 ; BZ 1919, 21, 201.

803. E. ABDERHALDEN and H. SCHAUMANN. Arch. ges. Physiol.1918, 172, 1 ; BZ 1919, 20, 478 ; C 1919, 90, I, 566.

804. J. J. NITZESCU. Arch. ges. Physiol. 1918, 172, 275 ; BZ 1919,20, 340; C 1919, 90, I, 560.

805. A. HARDEN and S. S. ZILVA. Biochem. Journ. 1918, 12, 408;BZ 1919, 20, 526.

806. E. M. DELF. Biochem. Journ. 1918,12? 416 ; BZ 1919, 20, 527.807. and R. F. SKELTON. Biochem. Journ. 1918, 12, 440 ;

BZ 1919, 20, 527.808. V. STEFANSSON. Journ. Amer. Med. Assoc. 1918, .71, 1715.809. W. TOBLER. Zschr. Kinderheilk. 1918, 18, 63.810. G. SCHAEFFER. Bull. Inst. Pasteur 1919, 17, 1, 41.811. A. HARDEN, S. S. ZILVA and G. F. STILL. Lancet 1919, I, 17.812. A. AUER. Biochem. Zschr. 1919, 93, 1 ; BZ 1919, 20, 479;

C 1919, 90, I, 560.813. N. M. SALEEBY. Philipp. Journ. of Science 1919, 14, 11.814. L. NICHOLLS. Journ. Trop. Med. Hyg. 1919, 22, 22.815. F. M. WELLS. Proc. Royal Soc. Med., Sekt. Odontol., 1919,

12, 23.816. I. J. KLIGLER. Journ. Exper. Med. 1919, 30, 31.817. T. B. OSBORNE and L. B. MENDEL. Proc. Soc. Exper. Biol.

Med. 1919, 16, 98.818. FEUILLE. SOC. Biol. 1919, 81, 870, 947.819. E. ALLEN. Anat. Rec. 1919, 16, 93.820. M. D. FLATHER. Biol. Bull. Marine Biol. Lab., Woods Hole,

1919, 36, 54-821. E. C. BULLEY. Biochem. Journ. 1919, 13, 103 ; BZ 1919

21, 439-822. E. V. MCCOLLUM, N. SIMMONDS and H. T. PARSONS. Journ.

Biol. Chem. 1919, 37, 155 ; BZ 1919, 21, 16.823. R. BERG. Berl. klin. Wschr. 1919, 56, 249.824. A. F. HESS and L. J. UNGER. Amer. Journ. dis. Childr. 1919,

17, 221.825. C. VOEGTLIN and C. G. LAKE. Amer. Journ. Physiol. 1919

47, 55*-826. C. M. JACKSON and C. A. STEWART. Amer. Journ. dis. Childr.

1919, 17, 329.827. A. M. MUCKENFUSS. Arch, pediatr. 1919, 36, 80.828. Scurvy and Antiscorbutic Properties of Foods. Journ. Amer.

Med. Assoc. 1919, 73, 271, 338, 1288.829. FREY. Arch. Physiol. 1919, 177, 119.830. ROTHSTEIN. Berl. klin. Wschr. 1919, 57, 154,831. T. B. OSBORNE and L. B. MENDEL. Journ. Biol. Chem. 1919,

37, 187; BZ 1919, 21, 16.

BIBLIOGRAPHY 365

832. P. PORTIER. Soc. Biol. 1919, 82, 59; BZ 1919, 21, 260.833. H. BIERRY. Soc. Biol. 1919, 82, 114 ; BZ 1919, 21, 260.834. A. L. DANIELS and N. J. MCCLURG. Journ. Biol. Chem. 191 9,

37, 201; BZ 1919, 21, 17.835. E. BERGMANN. Zschr. Kinderheilk. 1919, 20, 75 ; BZ 1920,

22, 96.836. F. EDELSTEIN and L. LANGSTEIN. Zschr. Kinderheilk. 1919,

20, 112; BZ 1920, 22, 100.837. T. B. OSBORNE, L. B. MENDEL and E. L. FERRY. Journ. Biol.

Chem. 1919, 37, 223 ; BZ 1920, 22, 222.838. M. H. GIVENS and H. B. MCCLUGAGE. Journ. Boil.

Chem. 1919, 37, 253; BZ 1920, 22, 223; C 1919, 90,III, 71.

839. F .W.BACH. Berl. klin. Wschr. 1919, 56,132 ; C1919, 90,1, 560.840. L. KULZ. Naturw. 1919, 17, 675 ; BZ 1920, 22, 96.841. E. WEILL and G. MOURIQUAND. Soc. Biol. 1919, 829 184;

BZ 1919, 21, 377-842. E. V. MCCOLLUM, N. SIMMONDS and H. T. PARSONS. Journ.

Biol. Chern. 1919, 37, 287.843. F. G. HOPKINS. Brit. Med. Journ. 1919, I, 507.844. P. RONDONI. Brit. Med. Journ. 1919, I, 542.845. E. MELLANBY. Lancet 1919, I, 407.846. Journ. of Physiol. 1919, 52, LIII, LIV.847. A. K. ANDERSON and R. FINKELSTEIN. Journ. Dairy Science

1919. 2, 374.848. B. C. P. JANSEN. Geneesk. Tijdschr. v. Nederl.-Indie 1919,

58, 173.849. W. A. T. LIND. Med. Journ. Australia 1919, 2, 197.850. Journ. Amer. Med. Assoc. 1919, 73, 1092.851. A. HARDEN and R. ROBISON. Journ. Royal Army Med.

Corps 1919, 32, 48 ; BPh 1920, 2, 107.852. R. ROBISON. Journ. Royal Army Med. Corps 1919, 32, 48853. A. H. SMITH. Journ. Royal Army Med. Corps 1919, 32, 93, 188.854. C. M. JACKSON. Arner. Journ. Anat. 1919, 25, 221.855. H. H. DONALDSON. Amer. Journ. Anat. 1919, 25, 237.856. J. C. DONALDSON. Amer. Journ. Anat. 1919, 25, 291.8$y. F. G. HOPKINS and H. CHICK. Lancet 1919, II, 28.858. M. E. D. CAMPBELL and H. CHICK. Lancet 1919, II, 320.859. R. E. BARNES and E. M. HUME. Lancet 1919, II, 323.860. M. H. GIVENS and H. B. MCCLUGAGE. Amer. Journ. Dis.

Childr. 1919, 18, 30.861. L. ZUNTZ. Arch. Gynakol. 1919, n o , 244 ; BZ 1919, 21, 15.862. T. B. ROBERTSON and L. A. RAY. Journ. Biol. Chem. 1919,

37> 393 ; C 1919, 9°> HI. *35-863. Journ. Biol. Chem. 1919, 37, 427; C I9*9# 9°>

HI, 130.864. Journ. Biol. Chem. 1919, 37, 443; C 1919* 9<>,

III, 136.

366 VITAMINS865 T B ROBERTSON and L A RAY Journ Biol Chern 1919

37, 455 , C 1919, 90, III, 137866 A HARDEN and S S ZILVA Journ Pathol Bactenol 1919,

22, 246867 J KOCH Arch prakt wiss Tierheilk 1919, 45, 263868 G TUHGE Arch Kinderheilk 1919, 67, 291869 J ADLER Arch Kinderheilk 1919 67, 321 BZ 1920, 22,146.870 F MAIGNON C r 1919, 168, 474 , BZ 1920, 22,100 C 1919,

90, I, 1041871 P B HAWK, C A SMITH and R C HOLDER Amer Journ

Physiol 1919, 48, 199 , BZ 1920, 22, 289872 C O JOHNS, A J FINSK and M S PAUL Journ Biol Chera

1919, 37> 497 c 1920, 91, III, 645873 T B OSBORNE L B MENDEL, E L TERRY and A J WAKE-

MAN Journ Biol Chem 1919 37, 557 , C 1920, 91, III, 645874 J C DRUMMOND Biochem Journ 1919, 13, 77, BZ 1919,

21, 438 , C 1919 90, III, 285875 Biochem Journ 1919, 13, 81 , BZ 1919, 21, 439 C

1919, 90, III, 286876 Biochem Journ 1919 13, 95 BZ 1919, 21, 439, C 1919,

90, III, 286877 G D BUCKNER, E H NOLLAU, R H WILKINS and J H

CASTLE Journ Agricult Res 1919, 16, 305 , C 1921, 92,I. 41

878 E V MCCOLLUM, N SIMMONDS and H T PARSONS JournBiol Chem 1919, 38, 113 , C 1920, 91, I I I , 601

879 A D EMMET and G O LUROS Journ Biol Chem 1919, 38,147 C 1920 91, III , 600

880 O W U T H Biochem Zschr 1919, 93, 289 , BZ 1919, 21, 230&81 G LINOSSIER Soc Biol 1919, 82, 381882 F MAIGNON SOC Biol 1919, 82, 398 BZ 1919, 21, 375 ,

C 1919, 90, I I I 441883 Soc Biol 1919, 82, 400, BZ 1919, 21, 375.884 W STEPP Zschr Biol 1919, 69, 495 , C 1919, 90, I I I , 446885 S S ZILVA and F M WELLS Proc Roy Soc London 1919,

90, B, 505 BZ 1920, 22, 21 , C 1919, 90, I I I , 503886 Proc Royal Soc London 1919, 90, B, 663 , BZ

1920, 22, 21887 W STEPP Zschr Biol 1919, 69, 574888 ZOETHOUT Amer Journ Physiol 1919, 48, 497.889 C VOEGTLIN and C N MYERS Amer Journ Physiol 1919,

48, 504890 A L DANIELS, A H BYFIELD and R LOUGHLIN Amer

Journ Dis Childr 1919, 18, 546.891 E F . TERROINE SOC Biol 1919, 82, 574 , BZ 1919, 21, 376892 T WOLLMAN Soc Biol 1919, 82, 593 , C 1919, 90, I I I , 391893 C RICHET Soc Biol 1919, 82, 601 , BZ 1919, 21, 377 , C

1919, 90, III , 391.

BIBLIOGRAPHY 367894 L A LARSON Amer Journ Physiol 1919, 49, 55 , C 1920,

91, III, 855895 J F MCCLENDON and W C C COLE Amer Journ Physiol

1919, 49, 145896 E ABDERHALDEN Arch, ges Physiol 1919 175, 187 BZ

1919, 21, 438 C 1919 90, III, 441897 T B OSBORNE, L B MENDEL E L FERRY and A J WAKE-

MAN Journ Biol Chem 1919 38,223 C 1920 91,111,601898 A D EMMET and G O LUROS Journ Biol Chem 1919 38,

257 , C 1920, 91, III, 600899 A F HESS and L J UNGER Journ Biol Chem 1919 38,

293 , C 1920 91, III, 601900 E B HART H STEENBOCK and F LETCHER Journ Biol

Chem 1919 38, 267 C 1920 91, III 601901 and D W SMITH Journ Biol Chem 1919, 38,

267 C 1920, 91, III 601902 M BURGER Zschr exper Med 1919,8,309, BZ 1919 21,379903 F MAIGNON C r 1919, 168, 626, BZ 1919 21, 441904 A D EMMET and F P ALLEN Journ Biol Chem 1919 38,325905 P HEHIR Ind Journ Med Res, Spec Indian Congr 1919,

Nr 44906 J A SHORTEN and C B ROY Ind Journ Med Res , Spec

Indian Congr 1919, Nr 60907 P HEHIR Ind Journ Med Res , Spec Indian Congr 1919,

Nr 79908 H STEENBOCK Science 1919 50, 352909 A SCHITTENHELM and H SCHLECT Zschr exper Med 1919,

9, 1 , BZ 1919, 21, 380910 Zschr exper Med 1919, 9, 40 BZ 1919, 21, 380911 Zschr exper Med 1919, 9, 68 BZ 1919, 21, 380912 Zschr exper Med 1919 9, 75 , BZ 1919, 21, 380913 Zschr exper Med 1919 9, 82 BZ 1919, 21, 380914 C H HAMSHIRE and G E G HAWKER Pharm Journ 1919

(4), 49, 82 , C 1919, 90, III, 893915 E C BTJLLEY Biochem Journ 1919, 13, 103 , BZ 1919,

21, 439916 S S ZILVA Biochem Journ 1919, 13,164 , BZ 1919, 21, 503917 Biochem Journ 1919, 13, 172 , BZ 1919, 21, 503918 H CHICK and E M DELF Biochem Journ 1919, 13, 199 ,

BZ 1919, 21, 502 , C 1919, 90, III, 728919 C J MARINUS Amer Journ Physiol 1919, 49, 238 , C 1920,

91, III, 850920 C E BLOCH Jahrb Kinderheilk 1919, 89, 405, BZ 1919,

21, 378921 C VOEGTLIN and C M MYERS Journ Pharm Exper Therap.

1919, 13, 301 C 1919, 90, III, 1023922 A D EMMET and G O LUROS Journ Biol Chem 1919, 38,441 , C 1920, 91, III, 652

368 VITAMINS923 R J WILLIAMS Journ Biol Chem 1919 38, 465 C 1920

91, IV 541924 R MCCARRISON Ind Journ Med Res 1919 6, 2759 5 Ind Journ Med Res 1919 6, 5509-76 Ind Journ Med Res 1919 6, 557927 L S PALMER Science 1919 50, 501928 A HARDEN and R ROBISON Lancet 1919 II 32°929 H CHICK E M HUME and R F Si ELTON Lancet 1919

II 322930 A HARDEN and S S ZILVA Lancet 1919 II 780931 F G HOPKINS H CHICK J C DRUMMOND A HARDEN and

E MELLANBY Nat Health Ins Med Res CommitteeSpec Rept 1919 Nr 38

932 L ASCHOFF and W KOCH Der Skorbut Jena 1919933 W V SIMON Munchn med Wschr 1919 66, 799 BZ 1919

21, 378

934 F MAIGNON SOC Biol 1919 82, 806 C 1919 90, III 686935 P PORTIER and L RANDOIN SOC Biol 1919 82, 990 BZ

1919 22, 147 C 1919 90, IV 1059936 F MAIGNON SOC Biol 1919 82, 1358 BZ 1920 22, 410937 T B OSBORNE L B MENDEL E L TERRY and A J WAKE

MAN Journ Biol Chem 1919 39, 29 C 1920 91, III 673938 T B OSBORNE A J WAKEMAN and E L FERRY Journ

Biol Chem 1919 39, 35 C 1920 91, III 672939 H C SHERMAN J C WINTERS and V PHILLIPS Journ Biol

Chem 1919 39, 53 C 1920 91, III 672940 R A DUTCHER Journ Biol Chem 1919 39, 63 C 1920

91, III 673941 F MAIGNON Recherches sur le role des graisses dans 1 utihsa

tion des albumoides Lyons 1919940 R MCCARRISON Ind Journ Med Res 1919 7, 167943 Ind Journ Med Res 1919 7, 188944 Ind Journ Med Res 1919 7, 269945 In(i Journ Med Res 1919 7, 279946 Ind Journ Med Res 1919 7, 283947 Ind Journ Med Res 1919 7, 308948 Ind Journ Med Res 1919 7, 342949 A F HESS and L J UNGER Journ Amer Med Assoc 1919,

73, 1353950 E PRITCHARD Brit Med Journ 1919 II 627951 O KIMURA D Zschr Nerv 1919 64, 153 BZ 1920 22, 147952 E ABDERHALDEN and A KOEHLER Arch ges Physiol 1919

176, 209 BZ 1920 22, 47953 Arch ges Physiol 1919 176, 236 BZ 1920 22, 238954 R BIERICH D Arch klin Med 1919 130,151 BZ 1920 22,98955 H CHICK and E M HUME Journ Biol Chem, 1919 39, 203956 E B HART and H STEENBOCK Journ Biol Chem 1919 39,209 C 1920 91, III 673

BIBLIOGRAPHY 369957 H BIERRY C r 1919, 169, 197, BZ 1920 22, 408958 F M BACHMANN Journ Biol Chem 1919, 39, 235 , C 1920,

91, III 670959 E S PALMER and II L KEMPSTER Journ Biol Chem 1919,

39> 299 > C 1920, 91, III 676960 Journ Biol Chem 1919, 39, 313 C 1920, 91,

III, 676961 Journ Biol Chem 1919, 39, 331 C 1920, 91

III, 676962 J F LYMAN and B RAYMUND Journ Biol Chem 1919, 39»

339, C 1920 91, III 675963 H v HOESSLIN Arch Hyg 1919 88, 147 BZ 1919, 21, 436.964 F EISLER Munchn med Wschr 1919, 66, 1057, BZ 919,

21, 436965 ALWENS Munchn med Wschr 1919, 66, 1072, BZ 919,

21, 500966 H ABELS Med Khmk 1915 15, 1085967 K SUGIURA and S R BENEDICT Journ Biol Chem 1919,

39, 421 , C 1920, 91, III, 695968 H B LEWIS Journ Biol Chem 1919, 40, 91 , C 1920, 91,

III 673969 R E BARNES and E M HUME Biochem Journ 1919, I3>

306 BZ 1920, 22, 223 C 1920, 91, I, 134970 T WOLLMAN Soc Biol 1919, 82, 1208 C 1920, 91, I, 537971 P GRABLEY D med Wschr 1919, 45,1238 BZ 1920, 22, 223972 J F MCCLENDON, W C C COLE, O ENGSTRAND and J E.

MIDDLEKAUFF Journ Biol Chem 1919, 40, 243 , C 1920,91, III, 721

973 H BIERRY C r 1919, 169, 924, BZ 1920, 22, 287974 C FUNK Journ of Physiol 1919, 53, 247 C 1920, 91,1, 433975 L DE BLIECK and C A R F BAUDET D tierarztl Wschr.

1919, 27, 591 , BZ 1920, 22, 289976 R G PADUA Phihpp Journ of Science 1919, 14, 481.977 Report of a Committee of Inquiry regarding the Prevalence of

Pellagra among Turkish Prisoners of War Journ RoyalArmy Med Corps 1919-20, 33, 426, 508 , 34, 70, 173, 272

978 T B OSBORNE and A J WAKEMAN Journ Biol Chem 1919,40, 383 , C 1920, 91, III, 747

979 H H MITCHELL Journ Biol Chem 1919, 40, 399 , C 1920,91, III, 721

980 K SUGIURA and S R BENEDICT Journ Biol Chem 1919,40, 449, C 1920, 91, III, 721

981 H STEENBOCK, E G GROSS and M T SELL Journ Biol.Chem 1919, 40, 501, C 1920, 91, III, 721

982 E V MCCOLLUM Haord's Dairyman 1919, 57, 1033.983 Proc Amer Phil Soc 1919 58, 41984 K G FALK Journ Ind Eng Chem 1919, 11, 1133 , C 1920,

91, III 845

37O VITAMINS985 N ZUNTZ Mitteil Verem z Forderung d Moorkultur 1919,

37, 437 C 1921, 92, I. 743986 A PEZARD C r 1919, 169, 1177, BZ 1920, 22, 411987 B C P JANSEN Meded Geneesk Lab Weltevreden 1920 3, A, 1988 Meded Geneesk Lab Weltevreden 1920, 3, A, 2298g and R H M MANGKOEWINOTO Meded Geneesk Lab

Weltevreden 1920, 3, A 51990 M GUGGENHEIM Die biogenen Araine und lhre Bedeutung

fur die Physiologie des pflanzlichen und tienschen Stoff-wechsels Springer Berlin, 1920

991 H BORUTTAU Umschau 1920, 7, BPh 1920 1, 45992 C N MYERS and C VOEGTLIN Proc Nat Acad Science

Washington 1920, 6, 3 C 1920, 91, III, 102993 F G BENEDICT Proc Nat Acad Science Washington 1920,

6, 7 BPh 1920, 3, 209994 A DUTCHER Proc Nat Acad Science Washington 1920, 6,

10, BPh 1920 3, 203 C 1920, 91, III, 101995 H C SHERMAN Proc Nat Acad Science Washington 1920,

6, 38 BPh 1920, 3, 210996 O OLSEN Zentralbl Baktenol 1920, 85, 12997 F M R WALSHE Med Science Abs Rev 1920, 2, 41.998 C VOEGTLIN, M H NEILL and A HUNTER US Publ Health

Serv, Hyg Lab Bull 1920, 116, 7999 R C LEWIS US Publ Health Serv, Hyg Lab Bull 1920,

116, 371000 C VOEGTLIN and R H HARRIS U S Publ Health Serv,

Hyg Lab Bull 1920 116, 731001 A F HESS Scurvy, Past and Present J B Lippmcott,

Philadelphia, 19201002 Internat Journ Publ Health 1920, 1, 3021003 DEHIO Vierteljahresschr ger Med u off San -Wesen 1920,

60, 27 BPh 1920, 4, 2281004 A TSCHIRSCH Schweiz med Wschr 1920, 50, 21 , BPh

1920, 1, 2691005 M FRANK Jahrb Kinderheilk 1920, 91, 21, BPh 1920, 1, 271.1006 E FREISE Jahrb Kinderheilk 1920 91,79, BPh 1920, 3,45.1007 S R ROBERTS Journ Amer Med Assoc 1920, 75, 21 ,

BPh 1920, 3, 2061008 M A BROWN Journ Amer Med Assoc 1920, 75, 27 , BPh

1920, 3, 2021009 W SALLEandM ROSENBERG Ergebn inn Med Kinderheilk.

1920, 19, 31 BPh 1921, 5, 2221010 E V MCCOLLUM LINTZ VERMILYE, LEGGET and BOAS Bull.

John Hopkins Hosp 1920, 31, 1 , BPh 1920, 1, 271.1011 MASON Bull John Hopkins Hosp 1920, 31, 66, BPh 1920,

2, 5291012 A R LEGGATE Edinburgh Med Journ 1920, 24, 32 ; BPh1920, 1, 45

BIBLIOGRAPHY 3711013. E SCIILESINGER Zsclir Schulgesundheitspflege 1920, 33, 37 ,

BPh 1920, 2, 5301014 O BOSSERT Berl khn Wschr 1920, 57,35 BPh 1920 1,4571015 H C SHERMAN, F L MCLEOD and M M KRAMER Proc Soc.

Exper Biol Med 1920 17, 411016 A F HESS and L J UNGER Proc Soc Exper Biol Med

1920, 17, 491017 W H EDDY and H C STEVENSON Proc Soc Exper Biol

Med 1920, 17, 521018 R MCCARRISON Ind Journ Med Res 1920 7, 6331019 M S ROSE Proc Soc Exper Biol Med 1920, 17, 66, BPh

1921, 6, 581020 A VISWALINGAM Journ Top Med Hyg 1920, 23, 461021 C A STEWART Amer Journ Physiol 1920, 48, 67, BZ

1920, 22, 2221022 C CIACCIO Ann Clm Med 1920, 10, 60 , BPh 1920, 3, 438 ,

C 1921, 92, I 1091023 G MOURIQUAND and P MICHEL SOC Biol 1920, 83, 62,

BPh 1920 1, 3691024 Discussion on Acidosis m Disease Brit Med Journ 1920, I

69 , BPh 1920 4, 2341025. W H WIIXCOX Brit Med Journ 1920, I 73 BPh 1920,

1, 191 , C 1920, 91, I, 7821026. E V MCCOLLUM and N SIMMONDS Amer Journ Physiol.

1920, 46, 275 , BZ 1920 22, 4081027 H STEENBOCK, P W BOUTWELL, E G GROSS and N T SELL

Journ Biol Chem 1920, 41, 81 , BPh 1920, 1, 119 , C 1920,91, III, 722

1028 E M PIERSON and R A DUTCHER Science 1920, 51, 701029 L E GUERRERO and I CONCEPCION Phihpp Journ of

Science 1920, 17, 991030 R MCCARRISON Proc Royal Soc London 1920, 91, B 103 ,

C 1920, 91, I, 5901031 BENINDE Veroff a d Geb d Medizinalverwalt 1920, 10,

121, BPh 1920, 1, 421032 M ROTHSTEIN Berl khn Wschr 1920, 57, 154, BPh 1920,

1, 46.1033 T L HILLS Journ Michigan State Med Soc 1920, 19, 169 ,

BPh 1920, 2, 391034 F G HOPKINS Brit Med Journ 1920, I 147, C 1920,

91, III, 4211035 A F HESS Brit Med Journ 1920, I, 154, C 1920, 91,

III, 4221036 W H. WILLCOX Brit Med Journ 1920, I, 158, C 1920,

91, III, 4221037 A BIGLAND Lancet 1920, 198, 243 BPh 1920, x, 1911038 J I ENRIGHT Lancet 1920, I, 3141039 A KRAFT Illinois Med Journ 1920,37,255, BPh 1920, 1,532.

372 VITAMINS1040 E ABDERHALDEN Arch ges Physiol 1920, 178, 260, BPh

1920, 1, 44 C 1920 91, I 5801041 KLOTZ Zschr Kmderheilk 1920,26,150 BPh 1920,4,3771042 H VOGT Jahrb Kmderheilk 1920 91, 278 BPh 1920, 2, 331043 J J WILLAMAN Journ Amer Chem Soc 1920, 42, 549,

BPh 1920, 1, 4441044 M LABBE" Pans med 1920 S 354 BPh 1920, 3, 4481045 H ARON Monatsschr Kmderheilk 1920, 15, 561 C 1920,

91, I, 7821046 F FIGUEIRA Rrv elm pediatr 1920 18, 6$ BPh 1920, 3, 501047 R LECOQ Bull sciences pharm I92O> 27> 82 , C 1920, 91,

I. 7331048 P NOVARO Pathologica 1920, 12, 87 BPh 1920 3, 2021049 M H GIVENS and H B MCCLTTGAGE Science 1920, 51, 2731050 A B MACALLUM Transact Royal Canada Inst 1920, 12, 1751051 W H EDDY Journ Biol Chem 1920, 41, XXXIV1052 H C SHERMAN Journ Biol Chem 1920, 41, 97 , BPh 1920,

i» 1851053 H STEENBOCK, E G GROSS and M T SELL Journ Biol

Chem 1920 41,149 BPh 1920, 3, 203 C 1920, 91, III 7221054 p W BOUTWELL, M T SELL and E G GROSS Journ

Biol Chem 1920, 41, 163 BPh 1920, 3, 204 C 1920,91, III, 722

1055 Discussion on the Present Position of Vitammes in ClinicalMedicine Brit Med Journ 1920, I, 47 BPh 1920, 4, 64

1056 R MCCARRISON Brit Med Journ 1920, I, 249 PBh 1920,1, 192 C 1920, 91, I, 580

1057 H CHICK Wien med "Wschr 1920, 70, 441 , BPh 1920, 1,268, C 1920, 91, I, 581

1058 P B HAWK, H R FISHBACK and O BERGEIM Amer JournPhysiol 1920, 48, 211 BZ 1920, 22, 289, C 1920, 91,1,285

1059 C M JACKSON and C A STEWART Journ Exper Zool 1920,30, 97, BPh 1920, 1, 187

1060 H E DUBIN and M J LEWI Amer Journ Med Science1920, 157, 264 BPh 1920, 1, 118

1061 W H JANSEN D Arch kirn Med 1920, 131, 144, 300,BPh 1920 1, 190

1062 S HARRIS New Orleans Med Surg Journ 1920, 72, 452 ,BPh 1920, 1, 190

1063 P PORTIER and L RANDOIN C r 1920, 170, 478 , BPh 1920,I, 117 C 1920 91, I, 897

1064 C MAASE and H ZONDEK Das Hungerodem G Thieme,Leipzig 1920

1065 L DREIFUS SOC Biol 1920, 83, 136 BPh 1920— 4, 1541066 F G HOPKINS, BOYD, W H WILLCOX, M WALLIS ROAF,

HUME and M DELF Proc Royal Soc Med 1920, 13, 1 ,BPh 1920, 2, 225

BIBLIOGRAPHY 3731067 H H HEPBURN Brit Med Journ 1920 I, 466 BPh 1920,

2, 2261 0 6 8 J G O L D B E R G E R a n d G A W H E E L E R U S P u b l H e a l t h S e r v

H y g L a b B u l l 1 9 2 0 , 1 2 0 , 7

1 0 6 9 M X S U L L I V A N U S P u b l H e a l t h S e r v H y g L a b B u l l

1 9 2 0 , 1 2 0 , 2 6

1 0 7 0 - — a n d K K J O N E S U S P u b l H e a l t h S e r v , H y g L a b

B u l l 1 9 2 0 1 2 0 , 1 1 7

1 0 7 1 U S P u b l H e a l t h S e r v H y g L a b B u l l 1 9 2 0 1 2 0 , 1 4 1

1 0 7 2 J A K I T T E L S O N A n a t R e c 1 9 2 0 1 7 , 2 8 1

1 0 7 3 M D A V I S a n d o t h e r s J o u r n H o m e E c o n o m 1 9 2 0 , 1 2 , 2 0 9

1 0 7 4 A D E M M E T S c i e n c e 1 9 2 0 5 2 , 1 5 7

1 0 7 5 R L E C O Q B u l l S c i e n c P h a r m a c o l 1 9 2 0 , 2 7 , 1 3 9 , C 1 9 2 0 ,

9 1 , I I I , 4 2 0

1 0 7 6 B u l l S c i e n c P h a r m a c o l 1 9 2 0 2 7 , 2 5 5 B P h 1 9 2 0 , 4 ,

3 7 7 C 1 9 2 0 9 1 , I I I , 2 0 6

1 0 7 7 F C L A I R B u l l S o c P a t h o l E x o t 1 9 2 0 , 1 3 , 1 9 1 B P h 1 9 2 0 ,

2 , 3 0 5

1 0 7 8 H B L E N C K E V e r o f i a d G e b d M e d i z m a l v e r w a l t 1 9 2 0 ,

1 1 , 2 5 3 = B P h 1 9 2 1 , s , 4 8

1 0 7 9 L I E B E R S P s y c h i a t r n e u r o l W s c h r 1 9 2 0 , 2 2 , 1 7 , 6 7 , B P h

1 9 2 0 , 2 , 3 0 3

1 0 8 0 E M U L L E R a n d M B R A N D T B e r l k l i n W s c h r 1 9 2 0 , 5 7 , 3 0 2 ,

B P h 1 9 2 0 3 , 4 7

1 0 8 1 r M A I G N O N S O C B i o l 1 9 2 0 , 8$, 2 7 2 , C 1 9 2 0 , 9 1 , I 7 8 3

1 0 8 2 T B O S B O R N E a n d L B M E N D E L J o u r n B i o l C h e m 1 9 2 0 ,

4 1 , 2 7 5 , B P h 1 9 2 0 , 1 , 4 5 2

1 0 8 3 M S R O S E J o u r n B i o l C h e m 1 9 2 0 , 4 1 , 3 4 9 , B P h 1 9 2 0 ,

2 , i o 5

1084 G LINOSSIER Soc Biol 1920, 83, 346 , BPh 1920, 1, 454 .C 1920, 91, I, 844

1085 K R U S E and HINTZE Munchn med Wschr 1920, 67, 445,BPh 1920, 1, 525

1086 E A KOHMAN Amer Journ Physiol 1920, 51, 378 , BPh1920, 2, 29 , C 1920, 91, III , 391

1087 H CHICK and E J DALYELL Zschr Kinderheilk 1920, 26,257 , BPh 1921, 5, 222

1088 A SCHEUNERT Zschr Infekt -Krhk, parasjt Krkh u Hygd Haustiere 1920, 21, 105 , C 1921, 92, I, 87

1089 H SEKINE Journ Tokyo Chem Soc 1920, 41, 4261090 Journ Tokyo Chem Soc 1920, 41, 4391091 E B HART, H STEENBOCK and C A HOPPERT Science 1920,

52, 3181092 C FUNK and H E DUBIN Science 1920, 52, 4471093 R A DUTCHER, C KENNEDY and C H ECKLES Science 1920,

52, 5%81094 C O JOHNS aad A J FINKS Journ Biol Chem 1920, 41,

379 , BPh 1920, 1, 451 , C 1920, 91, III , 205

374 VITAMINS1095 c ° JOHNS A J FINKS and M S PAUL Journ Biol

Chem 1920 41, 391 BPh 1920 1, 452 C 1920 91, III 2051096 E NASSAU Zschr Kxnderheilk 1920 26, 270 BPh 1921

5, 2211097 H CHICK Wien med Wschr 1920 70,411 BPh 1920 1,2681098 T B OSBORNE L B MENDFL and A J WAKEMAN Journ

Biol Chem 190 41, 451 BPh 1920 1, 454 C 192091, III 674

1099 A CHACE and V C MYERS Journ Amer Med Assoc 192074, 641 BPh 1920 2, 322 C 1920 91, III 571

1100 B H SHAW Brit Med Journ 1920 I 695 BPh 19202,329

nor J GOLDBERGER A C WHEELER and E SYDENSTRICKER PublHealth Repts 1920 35, 648 BPh 1920 45, 502 C 192192, I 333

1102 E BRAVETTA Arch gen neurol psichiatr 1920 1, 95 BPh1920 3, 206

1103 P PORTIER C r 1920 170, 755 BPh 1920 2, 291104 S E SWEITZER and H E MICHELSON Arch dermatol

syphilol 1920 2, 61 BPh 1920 3, 2121105 A HARDEN and S S ZILVA Biochem Journ 1920 14, 131

C 1920 91, III 1011106 A DESGREZ and H BIERRY C r 1920 170, 1209 BPh 1920

2, 403 C 1920 91, III 9341107 P PORTIER C r 1920 170, 1339 BPh 1920 3, 4431108 H CHICK and E M HUME Biochem Journ 1920 14, 135

BPh 1920 2, 109 C 1920 91, III 1011109 A HARDEN and R ROBISON Biochem Journ 1920 14, 171

BPh 1920 2, 107 C 1920 91, III 101mo P NOVARO Pathologica 1920 12, 133 BPh 1920 3, 48mi C PORCHER C r 1920 170, 1461 BPh 1920 3, 202iri2 H ARON Biochem Zschr 1920 103, 172 BPh 1920 1, 526

1920 91, III 1011113 F HOFMEISTER Biochem Zschr 1920 103, 218 BPh 1920

2, 37°1114 U FRANCHETTI RIV chn pediatr 1920 18, 193 BPh 1920

3> 2051115 E M DELF Biochem Journ 1920 14, 211 BPh 1920 2,

108 C 1920 91, III 1011116 A HARDEN and S S ZILVA Biochem Journ 1920 14, 263

BPh 1920 2, 1061117 EL HOLT Arch pediatr 1920 37, 429 BPh 1920 4, 2271118 J D COMRIE Edinburgh Med Journ 1920 24, 207 BPh

1920 3, 511119 A F HESS and L J UNGER Journ Amer Med Assoc 1920,

74, 217 BPh 1920 2, 5351120 M HINDHEDE Journ Amer Med Assoc 1920 74, 3811121 W CRAMER Brit Journ Exper Pathol 1920 1, 184

BIBLIOGRAPHY 3751122 C VOEGTLIN M X SULLIVAN and C N MYERS U S Publ

Health Repts 1920, 31, 935, 22051123 M HINDHEDE Skand Arch Pbysiol 1920, 39, 781124 E M DELF Scient Progress (London) 1920, 15, 6011125 South African Journ Science 1920, 17, 1211126 P NOVARO Pathologica 1920, 12, 183 BPh 1920, 4, 66,

C 1920, 92, I, 1831127 A LUMIERE C r 1920, 171, 271 BPh 1920 4, 377 , C 1921,

92, I, 1021128 F MAIGNON Ann me"d 1920 7, 280 BPh 1920, 3, 4341129 J F MCCLENDON Amer Journ Med Science 1920, 159, 477 ,

BPh 1920, 2, 5311130 A REICHE Med Khruk 1920, 16, 646 , BPh 1920, 2, 5301131 T B OSBORNE, L B MENDEL and A J WAKFMAN Journ

Biol Chem 1920, 41, 515 , BPh 1920, 2, 304 , C 1920, 91,III, 206

1132 Journ Biol Chem 1920, 41, 549 , PBh 1920,2, 401, C 1920, 91, III, 674

H33 V NELSON and A R LAMB Amer Journ Physiol 1920, 51*530 , BPh 1920 3, 204 C 1920, 91, III, 420

1134 L BORY Progr mid 1920, 47, 461 , BPh 1921, 5, 3741135 E MELLANBY Lancet 1920, 198, 856, BPh 1920, 1, 3631136 O ROSENHEIM and J C DRUMMOND Lancet 1920, 198, 862 ,

BPh 1920, i, 366 C 1920 91, III 2061137 A D BIGLAND Lancet 1920 198, 947 BPh 1920, 2, 4041138 C G KERLEY and L BERMAN Journ Amer Med Assoc

1920, 74, 1226 BPh 1920, 2, 3071139 B M VAN DRIEL Nederl Tijdschr Geneesk 1920, 64, 1350 ,

BPh 1920, 1, 5261140 W FAHRION Chem Umsch a d Geb d Fette, etc, 1920,

27, 97 C 1920, 91, III, 3921141 T B ROBERTSON and L A RAY Journ Biol Chem 1920,

42, 71, BPh 1920, 2, 402 C 1920, 91, III, 2041142 H STEENBOCK, P W BOUTWELL, M T SELL and E G GROSS

Journ Biol Chem 1920 42, 131 , BPh 1920, 2, 533 , C 1920,91, III, 722

1143 E B HART, H STEENBOCK and F LETCHER Journ BiolChem 1920, 42, 167, BPh 1920, 3, 209, C 1920, 91, III,205

1144 C N MYERS and C VOEGTUN Journ Biol Chem 1920, 42,igg , BPh 1920, 2, 533 , C 1920, 91, III, 256

1145 R J WILLIAMS Journ Biol Chem 1920, 42, 259, BPh1920 3, 48

1146 A L DANIELS and R LOUGHLIN Journ Biol Chem 1920,42, 359 » BPh 1920, 3, 436, C 1920, 91, III, 749

1147 T B OSBORNE, L B MENDEL and A J WAKEMAN JournBiol Chem 1920, 42, 465 , BPh 1920, 3, 437 , C 1920, 91,HI, 75O

376 VITAMINS1148 M H GivENsandH B MCCLUGAGE Journ Biol Chem 1920,

42, 491 , BPh 1920, 3, 437 , C 1920, 91, III 7491149 F A MOCKERIDGE Biochem Journ 1920, 14, 4321150 S S ZILVA Biochem Journ 1920, 14, 494, BPh 1920, 3,

442 C 1920, 91, III, 5601151 S S ZILVA and G E STILL Lancet 1920, I, 10081152 A F HESS and L J UNGER Amer Journ Dis Childr 1920,

1153 AH BYFIELD, A L DANIELS and R LOUGHLIN AmerJourn Dis Childr 1920, 19, 349 , BPh 1920, 3, 205 , C 1921,92, I, 43

1154 H SCHWARTZ Amer Journ Dis Childr 1920, 19, 3841155 E MARCHOUX Bull Soc Pathol Exot 1920, 13, 196, BPh

1920, 2, 5361156 A FLORENCE Schweiz Rundsch Med 1920, 20, 417, BPh

1920, 3, 2111157 J GOLDBERGER and G A WHEELER Arch Intern Med 1920,

25, 451, BPh 1920, 3, 2061158 F GALMOZZI Gazz osped elm 1920, 41, 460, BPh 1920,

3> 2051159 R H A PLIMMER Biochem Journ 1920, 14, 570, BPh

1920, 6, 62 , C 1921 92, I, 431160 K HULDSCHINSKY Zschr orthop Chir 1920, 89, 4261161 H S R E E D Journ Gen Physiol 1920, 2, 5451162 ZAMBRZYCKI Berl khn Wschr 1920, 57, 492 , BPh 1920, 2,

536, C 1920, 91, III, 1551163 A MAGNUS-LEVY Berl khn Wschr 1920, 57, 594, B P h

1920, 2, 5371164 E ZUNZ Scalpel 1920, 73, 497 , BPh 1921 5, 461165 H SCHLESINGER Zschr ges Neurol Psychiatr 1920, 59, 1 ,

BPh 1921, 5, 3711166 D M ADKINS Biochem Journ 1920, 14, 637, C 1921, 92,

I. 431167 J C DRUMMOND Biochem Journ 1920, 14, 660 , BPh 1921,

5, 372, C 1921, 92, I, 421168 and K H COWARD Biochem Journ 1920, 14, 661 ,

BPh 1921, 5, 223 , C 1921, 92, I, 421169 K H COWARD and J C DRUMMOND Biochem Journ 1920,

14, 665 BPh 1921, 5, 223 , C 1921, 92, I, 421170 J C DRUMMOND and K H COWARD Biochem Journ 1920,

14, 668, BPh 1921, 5, 223 C 1921, 92, I, 421171 Journ of Physiol 1920, 54, No 4, X X X , BPh 1921,

6, 2161172 S S ZILVA Biochem Journ 1920, 14, 7401173 K SIMPSON Brit Med Journ 1920, I I , 735, C 1920, 9 1 ,

III . 2591174 G GUILLAIN Bull m6m soc m£d hosp Pans 1920, 36, 808 ,

BPh 1920, 3, 448

BIBLIOGRAPHY 3771175 M LABBE" Bull mem soc med hosp Pans 1920, 36, 810 ,

BPh 1920, 3, 4481176 J I ENRIGHT Lancet 1920, 198, 998 BPh 1920, 2, 1091177 P W BASSET-SMITH Lancet 1920, 198, 1102, PBh 1920,

2, 3051178. J GOLDBERGER, G A WHEELER and E SYDENSTRICKER US

Publ Health Repts 1920, 35, 1650XI79 U S Publ Health Repts 1920, 35, 1701.H80 US Publ Health Repts 1920, 35, 26731181 D J HuLSHorr-PoL Nederl Tijdschr Geneeslc 1920, 64,

1625 , BPh 1920, 3, 2031182 B H SHAW Journ Ment Saenc 1920, 66, 244 , BPh 1920,

3, 4471183 H B LEWIS, E H COX and G E SIMPSON Journ Biol

Chem 1920, 42, 289 , BPh 1920, 3, 210 , C 1920, 91, III, 2891184 R A DUTCHER, E M PIERSON and A BIESTER Journ Biol

Chem 1920, 42, 301 BPh 1920, 3, 50 , C 1920, 91, III, 673.1185 H PUTZIG Therap Halbmonatschr 1920, 34, 2341186 G GAERTNER Therap Halbmonatschr 1920, 34, 321 , BPh

1920, 3, 48 , C 1921, 92, I, 421187 F D Bo YD Edinburgh Med Journ 1920, 24, 366, BPh

1920, 3, 4401188 E B FORBES, J O HALVERSON and J A SCHUXZ Journ

Biol Chem 1920, 42, 459 , BPh 1920, 3, 4441189 C O JOHNS and A J FINKS Journ Biol Chem 1920,

42, 569 , BPh 1920, 4, 230 C 1920, 91, III, 7211190 W T PORTER Amer Journ Physiol 1920, 52, 1211191 A SCHAMELHOUT Journ pharm Beige 1920, 2, 517 , C 1920,

91, III, 9351192 H E RoAr Journ Royal Army Med Corps 1920, 34, 534 ,

BPh 1920, 3, 4411193 S SIMPSON Proc Soc Exper Biol Med 1920, 17, 87 , BPh

1920, 5, 400 C 1921 92, I, 5861194 Die Wichtigkeit der akzessonschen Nahrstoffe Munchn med.

Wschr 1920, 67, 727 BPh 1920, 3, 491195 R MCCARRISON Brit Med Journ 1920, I, 882, C 1920,

91, III, 3921196 H DE WAEIX SOC Biol 1920, 83, 804 BPh 1920, 2, 394.1197 H BIERRY, P PORTIER and L RANDOIN-FANDARD SOC Biol.

1920, 83, 845 , BPh 1920, 4, 232 C 1920, 91, III, 9341198 F MAIGNON SOC Biol 1920, 83, 862, BPh 1920, 3, 52,

1920, 91, 3581199 G MOURIQUAND and P MICHEL SOC Biol 1920, 83, 865,

BPh 1920, 3, 51 , C 1920, 91, III, 9351200 H B LEWIS and L E ROOT Journ Biol Chem 1920, 43,

79 BPh 1920, 4, 500 , C 1920, 91, III, 7491201 H K FABER Journ Biol Chem 1920, 43, 113 , BPh 1921,6, 61, C 1920, 91, III, 751

378 VITAMINS1202 A D EMMET and G O LUROS Journ Biol Chem 1920,

43, 265 BPh 1920, 4, 378 C 1920 91, III 7501203 and M STOCKHOLM Journ Biol Chem 1920, 43, 287

BPh 1920, 4, 378 , C 1920, 91, III, 7501204 W H EDDY and H C STEVENSON Journ Biol Chem 1920,

43, 295 , BPh 1920, 4, 379 C 1920, 91, III, 750I2O5 Proc Soc Exper Biol Med 1920, 17, 122 , BPh

1921, S» 4961206 M X SULLIVAN and R E STANTON Arch Intern Med 1920,

26, 41 BPh 1920, 4, 641207 P R HOWE Dental Cosmos 1920, 62, 5861208 Dental Cosmos 1920, 62, 9211209 Journ Home Econom 1920, 12, 4821210. J H LARSON Arch Pediatr 1920, 37, 6101211 A LUMIERE Pans medicale 1920 19, 4741212 L VON MEYSENBUG Amer Journ Dis Childr 1920, 20, 206 ,

BPh 1921, 5, 491213 H ARON Jahrb Kmderheilk 1920 92, 82 BPh 1920, 4, 2261214 M Bucco Gazz intern med chirurg lg 1920, 26, 73, 85, 97,

113 123, 133 , BPh 1920, 4, 601215 R MCCARRISON Proc Royal Soc London 1920, 91, B, 103 ,

BPh 1920, 4, 631216 R UHLMANN Therap d Gegenwart 1920, 61, 132, BPh

1920, 4, 2341217 M BURGER Ergebn inn Med Kmderheilk 1920, 18, 189,

BPh 1920, 4, 621218 E TERRIEN Arch m£d des enfants 1920, 23f 404, BPh

1920, 4, 621219. A. LUMIERE Bull acad med 1920, (3), 83, 961220 Bull acad m6d 1920, (3), 83, 2741221. Bull acad me'd 1920 (3), 83, 3101222 A F HESS New York State Journ Med 1920, 20, 209,

BPh 1920 4, 671223 L B MENDEL New York State Journ Med 1920, 20, 212 ,

BPh 1920, 4, 681224 T B OSBORNE New York State Journ Med 1920, 20, 217 ,

BPh 1920, 4, 681225 M B MAVER Journ Amer Med Assoc 1920, 74, 934, BPh

1920, 2, 5361226 E F ROBB Science 1920, 52, 5101227 A LEBLANC Bull med 1920, 34, 491, BPh 1920, 2, 5361228 P AMEULLE Bull med 1920, 34, 495 BPh 1920, 2, 5361229 F M BACHMANN Zschr ges Brauwes 1920, 43, 222 , BPh

1921, S, 2221230 H BORUTTAU Zschr physikal -diatet Therap 1920, 24, 275,

BPh 1920, 4, 591231 C A SPRAWSON Quart Journ Med 1920, X3, 337, BPh

1920, 4, 231.

BIBLIOGRAPHY 3791232 R ISENSCHMID Schweiz med Wschr 1920, 50, 381, BPh

1920, 2, 535 , C 1920, 91, III 7511233 E B HART, H STEENBOCK and N R ELLIS Journ Biol

Chem 1920, 43, 383 BPh 1920, 3, 442 C 1920, 91, III 7501234 C VOEGTLIN U S Publ Health Repts 1920, 35, 14351235 R C OWEN Amer Journ Pharm 1920, 92, 467 BPh 1920,

4, 69 C 1920, 91, III, 8501236 W M BAYLISS Brit Med Journ 1920, II, S 72 , C 1920,

91, III, 4261237 H CHICK Brit Med Journ 1920, II, S 151, C 1920,

91, III, 4211238 E J DALYELL Brit Med Journ 1920, II, S 152 , C 1920,

91, III, 4211239 R MCCARRISON Brit Med Journ 1920, II, S 154 , C 1920,

91, 5221240 Brit Med Journ 1920, II, S 236 , C 1920, 91, III, 522.1241 K B RICH Journ Amer Med Assoc 1920, 75, 226, BPh

1920. 4, 591242 C W HOOPER, F S ROBSCHEIT and G H WHIPPLE Amer

Journ Physiol 1920, 53, 151, 167 , C 1921, 92, I, 57.1243 M STEPHENSON and A B CLARK Biochem Journ 1920,

14, 502 BPh 1920, 3, 439, C 1920, 91, III, 5601244 W DUFOUGERE' Bull Soc Pathol Exot 1920, 13, 603 , BPh

1920, 4, 3811245 E P HAUSSLER Naturwass Wschr 1920, 19, 593 BPh 1921,

S> 3721246 M SAMELSON Naturwissenschaften 1920, 8, 611 , BPh 1920,

4, 611247 L BLUM Presse med 1920 28, 685 , BPh 1921, 5, 471248 H ARON and S SAMELSON D med Wschr 1920, 46, 772 ;

BPh 1920, 3, 49 , C 1920, 91, I I I , 4941249 P W BASSET-SMITH Lancet 1920, 199, 997 , BPh 1921, 6, 61.1250 C BIDAULT and G COUTURIER SOC Biol 1920, 83, 1022;

BPh 1920, 3, 46 , C 1920, 91, I I I , 6461251 W CRAMER Amer Journ Physiol 1920, 54, I I , BPh 1920,

4, 5011252 E C SEAMAN Amer Journ Physiol 1920, 53, 101.1253 Proc Physiol Soc 1920, 15, 5 , BPh 1920, 4, 5011254 E ABDERHALDEN and E GELLHORN Arch ges Physiol 1920,

182, 28 , C 1920, 91, I I I , 5671255 Arch ges Physiol 1920, 182, 133 , BPh 1920, 4, 233 ;

C 1920, 91, I I I , 5611256 A B E H R E Zschr Unters Nahrgs - u Genussm 1920, 40, 202 ,

BPh 1921, s, 4701257 J STERN Zschr Unters Nahrgs - u Genussm 1920, 40, 204 ,

BPh 1921, 5, 4691258 J A NIXON Bristol Med -Chir Journ 1920, 37, 137, BPh

1921, 5, 222

VITAMINSJ AULDE Med Rec 1920, 98, 9, BPh 1920, 4, 374E B HART J G HALPIN, H STEFNBOCK and O N JOHNSON

Journ Biol Chem 1920 43, 421 BPh 1921 5, 48 C 1921,92, I, 42

A G STEVENSON Journ Royal Army Med Corps 1920,35, 218H FUHNER Therap Monatsh 1920, 34, 437 C 1920, 91,

III 566B SURL Journ Biol Chem 1920, 43, 443 BPh 1921 5,

44 C 1921, 92, I 41Journ Biol Chem 1920, 43, 457, BPh 1921, 5, 45,

C 1921, 92, I, 41C A GARY Journ Biol Chem 1920 43, 477, C 1921,

92 I, 44F A CAJORI Journ Biol Chem 1920, 43, 583 , BPh 1921,5, 490 , C 1921 92, I, 42

H ARON Berl klin Wschr 1920, 57, 773 BPh 1920 4, 60 ,C 1920, 91, III, 722

E MULLER Med Klmik 1920, 16, 1025 BPh 1921, 5, 46H ABELS Wien klin Wschr 1920, 33, 899F VERZAR and J BOGEL Biochem Zschr 1920, 108, 185

BPh 1920, 4, 46 C 1920, 91, III, 774F BREEST Biochem Zschr 1920 108, 309 BPh 1920, 4, 372J F MCCLENDON Proc Nat Acad Science 1920 6, C90E ABDERHALDEN and O SCHIITMANN Arch ges Physio]

1920, 183, 197 C 1920 91, III, 855B NEPPI Giorn chim md appl 1920, 2, 573 C 1921, 92

I, 334B B BEESON Arch dermatol syphilol 1920, 2, 337, BPh1920, 4, 574

E V MCCOLLUM Journ Franklin Inst 1920, 189, 421 ,BPh 1921 5, 220

H EppiNGERandE V ULLMANN Wien Arch inn Med 1920,1, 639, BPh 1921, 5, 225 C 1921, 92, I, 503

H CHICK and E J DALYELL Brit Med Journ 1920, II,S 546, C 1920, 91, III, 850

P. J DE KOCK and C BONNE Nederl Tijdschr Geneesk.1920, 64, II 965 BPh 1920, 5, 49

T B OSBORNE, L B MENDEL and A J WAKEMAN JournBiol Chem 1920, 44,1 BPh 1921, 5, 492 , C1921, 92,1, 102

E FREUDENBERG and P GYORGY Munchn med Wschr1920, 67, 1061 , BPh 1920 4, 381, C 1920, 91, III, 749

H BLOCK Munchn med Wschr 1920, 67, 1062, BPh 1920,4, 376

P DI MATTEI Policlmico 1920, 27, 1011, BPh 1921 5, 372G DE PAULA SOUZA and E V MCCOLLUM Journ Biol Chem

1920, 44, 113 , BPh 1921, 5, 373 , C 1921, 92, I, 58H A MATTILL and R E CONKLIN Journ Biol Chem 1920,

44, 137, BPh 1920, 5, 491, C 1921, 92, I, 101

BIBLIOGRAPHY 3811286 E W MILLER Journ Biol Chem 1920, 44, 159 , BPh 1921,

5, 372 C 1921, 92, I, 1021287 B K WHIPPLE Journ Biol Chem 1920, 44, 175 BPh 1921,

5> 373 » C 1921 92, I, 1021288 E B HART, G C HUMPHREY and S LEPKOWSKY Journ

Biol Chem 1920, 44, 189 BPh 1921, 5, 491 , C 1921, 92,I, 102

1289 H K FABER Proc Soc Exper Biol Med 1920, 17, 140,BPh 1921, s, 374, C 1921, 92, I, 542

1290 S GOLDFLAM Wien med Wschr 1920, 70, 20n , BPh 1921,5, 496

1291 O H PLANT Journ Pharm Exper Therap 1920, 16, 311C 1921, 92, I, 189

1292 I G MACY and L B MENDEL Jonrn Pharm Exper Therap1920, 16, 345 BPh 1921, 6, 218

1293 W G KARR Journ Biol Chem 1920, 44, 255 , BPh 1921,6, 220 , C 1921 92, I, 226

1294 Journ Biol Chem 1920, 44, 277, BPh 1921, 6, 221,C 1921, 92, I, 226

1295 A L DANILLS and R LOUGHLIN Journ Biol Chem 1920, 44,381, BPh 1921, 6, 59 , C 1921 92, I, 226

1296 T B ROBERTSON and L A RAY Journ Biol Chem 1920,44, 439, C 1921, 92, I, 228

1297 C FUNK and H E DUBIN Journ Biol Chem 1920, 44,487 C 1921, 92, I, 286

1298 F K SWOBODA Journ biol chem 1920, 44, 531 , BPh1921, 6, 217

1299 H T PARSONS Journ Biol Chem 1920, 44, 587, BPh1921, 6, 219, C 1921, 92, I, 300

1300 E V MCCOLLUM and H T PARSONS Journ Biol Chem1920, 44, 603 BPh 1921, 6, 62 C 1921, 92, I, 301

1301 H SIMONNET Soc Biol 1920, 83, 1508 , BPh 1921,6, 221C 1921, 92, I 334

1302 E ABDLRHALDEN and L SCHMIDT Arch ges Physiol 1920,185, 141, BPh 1921 6, 222

1303 H W WILTSHIRE Journ Royal Army Med Corps 1920, 35,469 , BPh 1921, 6, 223

1304 A HOLST and T FROLICH. Journ trop med hyg 1920, 23,261 BPh 1921, 6, 224

1305 O WELTMANN Wien Arch inn Med 1920, 2, 1211306 A CRAMER and P ScHirF Rev mdd Suisse rom 1920, 40,

746 BPh 1921, 6, 2241307 O FORTH and E NOBEL Biochem Zschr 1920, 109, 103,

C 1921, 92, I, 621308 S ROSENBAUM Biochem Zschr 1920, 109, 271 C 1921,

92, I, 411309 T SOLLMANN, O H SCHETTLER and N C WETZEL Journ

pharm exper therap 1920, 16, 273 , C 1921, 92, I, 190

382 VITAMINS1310 F E PECKHAM Journ Amer Med Assoc 1920, 75, 1317 ;

BPh 1921, by 581311 W L B R O W N Brit Med Journ 1920, II, 687, C 1921, 92,

I. 1931312 H GRABER Biedermanns Zentralbl 1920, 49, 463, BPh

1921, 6, 581313 M STEPHENSON Biochem Journ 1920, 14, 715 C 1921,

92, I, 7441314 F G HOPKINS Biochem Journ 1920, 14, 721 , C 1921,

92, I 7441315 Biochem Journ 1920, 14, 725 C 1921 92, I, 7441316 E NOBEL Wien Mm Wschr 1920, 33, 1123 , C 1921, 92,

I, 7441317 A SCALA Ann d ig 1920, 30, 251 , C 1921, 92, I, 3331318 V K LA MER and H L CAMPBELL Proc Soc Exper Biol

Med 1920, 18, 321319 D T MCDOUGAL Proc Soc Exper Biol Med 1920, 18, 851320 G M FINDLAY Journ Pathol Bacteriol 1920 23, 4901321 E L FERRY Journ Lab Chn Med 1920, 5, 7351322 L POPIELSKI Wydz lek Lwow 1920, 67 , B P H 1920, 4, 532

C 1921, 92, I 3371323 S FRANKEL and E SCHWARZ Biochem Zschr 1920, 112,

203 C 1921, 92, I, 3761324 J C DRUMMOND and K H COWARD Journ Biol Chem 1920,

44, 734, C 1921 92, I, 45913 25 S S ZILVA Journ biol chem 1920, 44, 734 C 1921 92,

I, 4601326 J C DRUMMOND, J GOLDING, S S ZILVA and K H COWARD

Journ Biol Chem 1920, 44, 742 , C 1921, 92, I, 4601327 A D STAMMERS Brit Med Journ 1920, I I , 919, C 1921,

92, I, 4601328 H M M MACKAY Brit Med Journ 1920, I I , 929, C 1921,

92, I 4601329 W D HALLIBURTON Brit Med Journ 1920, II , 951 , C 1921,

92, I 4601330 R DUTCHER, C E ECKLES, C D DAHLE, S W MEAD and O G

SCHAEFER Journ Biol Chem 1920, 45, 119, C 1921, 92,I. 5°3

1331 T B OSBORNE and L B MENDEL Journ Biol Chem 1920,45, 145 BPh 1921, 6, 218, C 1921, 92, I, 503

1332 A F HESS, L J UNGER and G C SUPPLE Journ Biol

Chem 1920 45, 229 BPh 1921, 6, 223 , C 1921, 92, I, 5031333 LIECHTI and RITTER Landw Jahrb d Schweiz 1921, 11334 H SETTLER and H NEHRING Zschr Tuberkulose 1921,

34,11335 F G HOPKINS Lancet 1921, I, 1

1336 G A HARTWELL Lancet 1921, I, 401337 B SURE and J W READ Journ Agric Res 1921, 22, 5.

BIBLIOGRAPHY 3831338 W ALWENS Therap Halbmonatsh 1921, 35, 5, C 1921,

92, I, 462*339 J C DRUMMOND Pag Breeders' Ann 19211340 C H KELLAWAY Proc Royal Soc London 1921, 92, B, 6.1341 M MURATA Japan Med World 1921 1, 121342 P FILDES Brit Journ Exper Pathol 1921, 2, 161343 F M TOZER Biochem Journ 1921, 15, 281344 E M HUME Biochem Journ 1921, 15, 301345 G MOURIQUAND and P MTCHEL SOC biol 1921, 84, 41 ,

C 1921, 92, I, 5421346 C MOURIQUAND and P MICHEL SOC bid 1921, 84, 41,

C 1921, 92, I 5451347 A MOREL, G MOURIQUAND and M MIGUET SOC biol 1921,

84, 46, C 1921, 92, I, 5411348 W J RUTHERFORD Brit Journ Ophthalmol 1921, 5, 601349 D N PATON and A H WATSON Journ Exper Pathol 1921,

2,751350 A H WELLS Philipp Journ of Science 1921, 19, 671351 A SEIDELL Journ ind eng cliem 1921 13, 721352 R R RENSHAW Amer Naturalist 1921 55, 731353 S V TELrER Journ of Physiol 1921, 54, CV1354 A HARDEN Journ Soc Chem Ind 1921, 40, R 79J355 J C DRUMMOND Journ Soc Chem Ind 1921, 40, 811356 N BEZssoNOFr C r 1921, 172, 92 C 1921, 92, I, 4621357 T B OSBORNE and L B MENDEL Journ Biol Chem 921,

45, 2771358 M B MCDONALD and E V MCCOLLUM Journ Biol Chem

1921, 45, 307 , C 1921 92, I, 7411359 E V MCCOLLUM, N SIMMONDS, H T PARSONS, P G SHIPLEY

and E A PARK Journ Biol Chem 1921, 45, 333 . C 1921,92, I, 743

1360 P G SHIPLEY, E A PARK, E V MCCOLLUM N SIMMONDSand H T PARSONS Journ Biol Chem 1921, 45, 343,C 1921, 92, I, 743

1361 V K LA MER H L CAMPBELL and H C SHERMAN ProcSoc Exper Biol Med 1921, 18, 122

1362 T B OSBORNE and L B MENDEL Proc Soc Exper BiolMed 1921, 18, 136

1363 M H GIVENS, H B MCCLUGAGE and E G VAN HORNE PTOCSoc Exper Biol Med 1921, 18, 140

1364 A F HESS and C J UNGER Proc Soc Exper Biol Med.1921, 18, 143

1365 G R COWGILL Proc Soc Exper Biol Med 1921. 18, 1481366 K BLUNT and C C WANG Journ HomeEconom 1921,13,971367 C E BLOCH Journ Hyg 1921, 19, 2831368 A LUMIERE Ann inst Pasteur 1921, 35, 1021369 H C SHERMAN, V K LA MER and H L CAMPBELL Proc

Natv Acad Science 1921, 7, 279

384 VITAMINS1370 S S ZILVA and M MIURA Lancet 1921, I, 3231371 K SCHWEIZER Mitteil Lebensm-Untersuch Hyg 1921 11,

193 C 1921 92, I 5791372 E J FULMER V E NELSON and T F SHERWOOD Journ

Amer Chem Soc 1921, 43, 186 C 1921, 92, I 685J373 Journ Amer Chem Soc 1921, 43, 1911374 G C DUNHAM Miht Surg 1921, 48, 223J375 P GOY C r 1921, 172, 2421376 E ABDERHALDEN and W BRAMMERTZ Arch ges Physiol

1921 186, 265 , C 1921 92, I, 6901377 H EULER and A PEITERSSON Zschr physiol Chem 1921

114, 41378 A J DAVEY Bjochem Journ 1921, 15, 831379 G M FINDLAY Biochem Journ 1921 15, 1041380 H JEPHCOTT and A L BACHARACH Biochem Journ 1921,

i5» 129J381 G A HART WELL Biochem Journ 1921, 15, 1401382 T B OSBORNE and C S LEAVEN WORTH Journ Biol Chem

1921 45, 4231383 M X SULLIVAN and P R DAWSON Journ Biol Chem 1921,

45» 4731384 U KLUNDER Chem -Ztg 1921, 45, 2251385 E ABDERHALDEN Arch ges Phsyiol 1921, 187, 801386 H ARON and R GRALKA Chem Ztg 1921, 45, 2451387 G M FINDLAY Journ Pathol Bactenol 1921, 24, 1751388 M H GIVENS and H B MCCLUGAGE Proc Soc Exper Biol

Med 1921, 18, 1641389 T B OSBORNE and L B MENDEL Proc Soc Exper Biol

Med 1921, 18, 1671390 E M HUME Biochem Journ 1921, 15, 1631391 W H EDDY The Vitamin Manual Williams & Wilkms Co ,

Baltimore, 19211392 J F MCCLENDON, W S BOWERS and J P SEDGWICK Journ

Biol Chem 1921, 46, IX1393 M H GIVENS and I G MACY Journ Biol Chem 1921 46, IX1394 J r MCCLENDON and S M DICK Journ Biol Chem 1921,

46, XI1395 V E NELSON, E I FULMER and R CESSNA Journ Biol.

Chem 1921 46, 771396 R J WILLIAMS Journ Biol Chem 1921, 46, 1131397 S S ZILVA Lancet 1921, I, 4781398 P B HAWK C A SMITH and O BERGEIM Amer Journ

Physiol 1921, 55, 3391399 C O JOHNS and A J FINKS Amer Journ Physiol 1921,

55, 4551400 A F HESS Journ Amer Med Assoc 1921 76, 6931401 D B PHEMISTER E M MILLER and B E BONAR Journ.

Amer Med Assoc 1921, 76, 850.

BIBLIOGRAPHY 3851402 T B OSBORNE and L B MENDEL Journ Amer Med Assoc

1921, 76, 9051403 I M WASON Journ Amer Med Assoc 1921, 76, 9081404 P B HAWK, C A SMITH and O BERGEIM Amer Journ

Physiol 1921, 56, 331405 E C VAN LEERSUM Nederl Trjdschr Geneesk 1921, 65,

Nr 161406 H C SHERMAN and A M PAPPENHEIMER Proc Soc ExpeT

Biol Med 1921, 18, 1931407 D J DAVIS Journ Infect Dis 1921, 29, 171, 178, 1871408 J W MCLEOD and G A WYON Journ Pathol Bactenol

1921, 24, 2051409 P ERLACHER Wien klin Wschr 1921, 34, 2411410 J A SHORTEN and C B ROY Biochem Journ 1921,

IS, 2741411 W STORM VAN LEEUWEN and F VERZAR Journ pharmacol

exper therap 1921, 18, 2931412 E B HART, H STEENBOCK and N R ELLIS Journ Biol

Chem 1921, 46, 3091413 N R ELLIS, H STEENBOCK and B E HART Journ Biol

Chem 1921, 46, 3671414 H C SHERMAN, M E ROUSE, B ALLEN and E WOODS

Journ Biol Chem 1921, 46, 5031415 M IDE Journ Biol Chem 1921, 46, 5211416 M B MCDONALD and E V MCCOLLUM Journ Biol Chem

1921, 46, 5251417 L S PALMER, C KENNEDY and H. L KEMPSTER Journ

Biol Chem 1921, 46, 5591418 L FINDLAY, D N PATON and J S SHARPE Quaterl Journ

Med 1921, 14, 3521419 G V ANREP and J C DRUMMOND Journ of Physiol 1921,

54, 3491420 A M PAPPENHEIMER and J MINOR Journ Med Res 1921,

42, 39i1421 A W WILLIAMS and O R POVITZKY Journ Med Res 1921,

42, 4051422 E V ANDERSON, R A DUTCHER, C H ECKLES and J W

WILBUR Science 1921, 53, 446.1423 N BEZSSONOFF C r 1921, 173, 4661424 H GODLEWSKI Presse medicale 1921, 29, 6821425 E ADBERHALDEN Arch ges Physiol 1921, 188, 601426 H STEENBOCK, M T SELL and M V BUELL Journ Biol

Chem 1921, 47, 891427 E V MCCOLLUM, N SIMMONDS and H T PARSONS Journ

Biol Chem 1921, 47, in1428 Journ Biol Chem 1921, 47, 1391429 Journ Biol Chem 1921, 47, 1751430 Journ Biol Chem 1921, 47, 207

386 VITAMINS1431 E V MCCOLLUM N SIMMONDS and H T PARSONS Journ

Biol Chem 1921 47, 2351432 H A MATTIIX Proc Soc Exper Biol Med 1921 18, 2421433 E COOPER Proc Soc Exper Biol Med 1921 18, 2431434 F G HOPKINS Biochem Journ 1921 15, 2861435 E WERTHEIMER and E WOLF Zschr Kinderheilk 1921

28, 2951436 E NOBEL Zschr Kinderheilk 1921 28, 3481437 H G WELLS Eye Troubles of Roumanian Children 19211438 F M TOZER Journ Pathol Bactenol 1921 24, 3061439 M X SULLIVAN R E STANTON and P R DAWSON Arch

Intern Med 1921 27, 3871440 W J MCNEAL Amer journ Med Science 1921 161, 4691441 E V MCCOLLUM N SIMMONDS P G SHIPLEY and E A PARK

Amer Journ Hyg ig i 1, 4921442 P G SHIPLEY E A PARK E V MCCOLLUM and N SIMMONDS

1921 1, 5121443 A SEIDELL U S Publ Health Repts 1921 36, 6651444 T THJOTTA Journ Exper Med 1921 33, 7631445 W F TANNER and G L ECHOLS Journ Amer Med Assoc

1921 76, 13371446 The Loss of Antiscorbutic Potency in Foods Journ Amer

Med Assoc 1921 76, 15771447 P G SHIPLEY E A PARK E V MCCOLLUM and N SIMMONDS

John Hopkins Hosp Bull 1921 32, 1601448 A D EMMET Journ Amer Pharm Assoc 1921 10, 1761449 A M PAPPENHEIMER G F MCCANN T F ZUCKER and A F

HESS Proc Soc Exper Biol Med 1921 18, 2671450 E V MCCOLLUM N SIMMONDS P G SHIPLEY and E A PARK

Proc Soc Exper Biol Med 1921 18, 2751451 P G SHIPLEY E A PARK E V MCCOLLUM and 1ST SIM

MONDS Proc Soc Exper Biol Med 1921 18, 2771452 T M RIVERS Journ Amer Med Assoc 1921 76, 17441453 Further Facts about Ricketts Journ Amer Med Assoc

1921 76, 18441454 W H EDDY H L HEFT H C STEVENSON and R JOHNSON

Journ Biol Chem 1921 47, 2491455 H STEENBOCK M T SELL and P W BOUTWELL Journ

Biol Chem 1921 47, 3031456 A F HESS G F MCCANN and A M PAPPENHEIMER Journ

Biol Chem 1921 47, 395*457 J F MCCLENDON Journ Biol Chem 1921 47, 4111458 A J FINKS and C O JOHNS Amer Journ Physiol 1921,

56, 4041459 S S ZILVA and M MIURA Biochem Journ 1921 15, 4221460 S S ZILVA J GOLDING J C DRUMMOND and K H COWARD

Biochem Journ 1921 15, 4271461 A HARDEN and S S ZILVA Biochem Journ 1921 15, 438

BIBLIOGRAPHY 3871462 H C SHERMAN Physiol Rev 1921, 1, 5981463 W CRAMER, A H DREW and J C MOLTRAM Lancet 1921,

I, 9631464 H C SHERMAN, V K LA MER and H L CAMPBELL Journ

Amer Chem Soc 1921 44.1465 R A DUXCHER H M HARSHAW and J S HALL Journ

Biol Chem 1921 47, 4831466 E V MCCOLLUM N SIMMONDS P G SHIPLEY and E A

PARK Journ Biol Chem 1921 47, 5071467 W H WILSON Journ of Hyg 1921 20, 11468 A F HESS and L J UNGER Journ Amer Med Assoc 1921,

77, 391469 E REYNOLDS and D MACOMBER Journ Amer Med Assoc

1921, 77, 1691470 G R COWGILL Proc Soc Exper Biol Med 1921 18, 2901471 A F HESS and L J UNGER Proc Soc Exper Biol Med

1921, 18, 2981472 M DAVIS and J OUTHOUSE Amer Journ Dis Childr 1921,

21, 3071473 H J GERSTENBERGER Amer Journ Dis Childr 1921,21,3151474 G M FINDLAY Biochem Journ 1921, 15, 3551475 P W BASSET-SMITH Trop Dis Bull 1921, 18, 3071476 H PENAU and H SIMONNET SOC Biol 1921, 85, 1981477 G M FINDLAY Journ Pathol Bactenol 1921 24, 4461478 S MORGULIS Amer Journ Physiol 1921 57, 1251479 R A DUTCHER Journ Ind Eng Chem 1921 13, 11021480 A D EMMET Journ Ind Eng Chem 1921, 13, 11041481 R R WILLIAMS Journ Ind Eng Chem 1921, 13, 11071482 V K LA MER Journ Ind Eng Chem 1921, 13, 1108.1483 C FUNK Journ Ind Eng Chem 1921, 13, 11101484 A SEIDELL Journ Ind Eng Chem 1921, 13 11111485 A F HESS Journ Ind Eng Chem 1921, 13, 11151486 E B HART, H STEENBOCK and C A HOPPERT Journ. Biol.

Chem 1921, 18, 331487 H A MATTILL Science 1921, 54, 1761488 T M RIVERS and A K POOLE Bull John Hopkins Hosp.

1921, 32, 2021489 P W BASSET-SMITH Lancet 1921 II, 3211490 A H MACKLIN and L D A HUSSEY Lancet 1921 II, 3221491 Nutritional Rehabilitation Journ Amer Med Assoc 1921,

77, 289G M FINDLAY Journ Pathol Bactenol 1921, 24, 454Experimental Rickets Brit Med Journ 1921 II, 454V KORENCHEVSKY Brit Med Journ 1921 II, 547A D STAMMERS Biochem Journ 1921, 15, 489F O SANTOS Proc Soc Exper Biol Med 1921, 19, 2A F HESS, L J UNGER and A M PAPPENHEIMER Proc.Soc Exper Biol Med 1921, 19, 8

388 VITAMINS1498 C FUNK and H E DUBIN Proc Soc Exper Biol Med 1291,1499 C A SMITH, O BERGEIM and P B HAWK Proc Soc Exper

Biol Med 1921 19, 221500 A F HESS and P GUTMAN. Proc Soc Exper Biol Chem.

1921, 19, 311501 Vitamin A and Rickets Journ Amer Med Assoc 1921,

77, 3831502 H EULER and A PETTERSON Zschr Physiol Chem 1921,

"S» 1551503 H DAMIANOVICH Revist Assoc Med Argentina 1921, 34, 2791504 C P MATHETJ Revjst Assoc Med Argentina 1921, 34, 28605 and H DAMINANOVICH Revist Assoc Med Argentina

1921,34,303, Journ Amer Med Assoc 1921,77,1139 11401506 K SCHWEIZER Bull assoc chun sucr dist 1921, 38, 3041507 E SMITH and G MEDES Journ Biol Chem 1921, 48, 3231508 E W MIIXFR Journ Biol Chem 1921 48, 3291509 H K FABER Amer Journ Dis Childr 1921, 21, 4011510 G R COWGILL Amer Journ Physiol 1921, 57> 42°1511 R A DUTCHER and S D WILKINS Amer Journ Physiol

1921 57, 4371512 A HARDEN and R ROBISON Biochem Journ 1921, 15, 5211513 K H COWARD and J C DRUMMOND Biochem Journ 1921,

15, 53o1514 J C DRUMMOND K H COWARD and A F WATSON Biochem

Journ 1921, 15, 5401515 C PASCH Zentralbl Gynakol 1921, 45, 7441516 R BERG Chem-Ztg 1921, 15, 849, 10801517 P G SHIPLEY, E A PARK, G F POWERS, E V MCCOLLUM

and N SIMMONDS Proc Soc Exper Biol Med 1921, 19, 431518 J F MCCLENDON and H BANGNESS Proc Soc Exper Biol

Med 1921 19, 591519 H STEENBOCK, E M NELSON and E B HART Amer Journ.

Physiol 1921, 58, 141520 G R COWGILL and L B MENDEL Amer Journ Physiol

58, 1311521 W D FLEMING Journ Biol Chem 1921, 49, 1191522 T THjOTTAandO T AVERY Journ Exper Med 1921,34,971523 H G SHERMAN and A PAPPENHEIMER Journ Exper. Med

1921, 34» 1891524 T THOLIN Zschr physiol Chem 1921, 115, 2351525 J C DRUMMOND Amer Journ Publ Health, 1921,11,5931526 V B APPLETON Amer Journ Publ Health, 1921, 11, 6171527 D J DAVIS Journ Amer Med Assoc 1921, 77, 6831528 R MCCARRISON Studies in deficiency Disease London, 19211529 V B APPLETON Journ Home Econom 1921, 13, 6041530 E J DALYELL and H CHICK Lancet 1921, II, 8421531 E M HUME and E NIRENSTEIN Lancet 1921, II, 849

BIBLIOGRAPHY 3891532 J HOWLAND and B KRAMER Amer Journ Dis Childr 1921,

22, 1051533 A F HESS and L J UNGER Amer Journ Dis Childr 1921,

22, 1861534 E ABDERHALDEN Arch ges Physiol 1921 192, 1631535 an(^ WERTHEIMER Arch ges Physiol 1921, 192, 1741536 H S MITCHELL and L B MENDEL Amer Journ Physiol

1921, 58, 2111537 A W DOWNS and N B EDDY Amer Journ Physiol 1921,

58, 2961538 E A PARK and J HOWLAND Bull John Hopkins Hosp

1921, 52, 5411539 A MOREL, G MOURIQUAND, P MICHEL and L THEVON SOC

Biol 1921, 85, 4691540 G MOURIQUAND and P MICHEL SOC Biol 1921, 85, 4701541 J M JOHNSON and C W HOOPER U S Publ Health Repts

1921, 36, 20371542 U s Publ Health Repts 1921, 36, 20441543 P G SHIPLEY, E V MCCOLLUM and N SIMMONDS Journ

Biol Chem 1921 49, 3991544 M J ROSENAU Boston Med Surg Journ 1921, 184, 4551545 S S ZILVA and M MIURA Biochem Journ 1921, 15, 6541546 E V MCCOLLUM N SIMMONDS, P G SHIPLEY and E A PARK

Journ Biol Chem 1921, 50, 51547 A F HESS, L J UNGER and A M PAPPENHEIMER Journ

Biol Chem 1921 50, yj1548 S G ROSE Amer Journ Dis Childr 1921, 22, 2321549 T THJOTTA and O T AVERY Journ Exper Med 1921,

34, 4551550 H DAMIANOVICH SOC Biol 1921, 85, 5911551 G M FINDLAY Journ Amer Med Assoc 1921,77,1604 16051552 H M EVANS and K S BISHOP Anat Rec 1922, January1553 V K LA MER H L CAMPBELL and H C SHERMAN Journ

Amer Chem Soc 1922, 441554 H C SHERMAN and L H SMITH The Vitamins. Chemical

Catalogue Company, New York, 19221555 Aussprache iiber Skorbut Med Khnik 1922, 18, 846.1556 UMBER Med Khnik 1922, 18, 851

I N D E X

A, fat-soluble, 22, 138, 159, 160, 184—187, 188, 189, 191, 194, 195, 200,207, 208, 210, 211, 219-241 (forDetails see Table of Contents,Chapter Six), 246, 249, 254, 265,270, 283, 294, 295, 296, 314, 317,322, 334, 335, 336

compounded with B, 222, 226ABDERHALDEN, 22, 30, 31, 34, 36, 41, 42,

44, 45, 46, 48, 49, 58, 59, 73, 139,146, 147, 148, 155, 159, 167, 193,195, 202, 352, 367, 372, 384, 385,389

ABDERHALDEN and BRAMMERTZ, 203,384ABDERHALDEN andEwALD, 74, 122, 139,

360ABDERHALDEN and GELLHORN, 379ABDERHALDEN and KOEHLER, 194, 368ABDERHALDEN and LAMPE, HI , 1x8,121,

346ABDERHALDEN and SCHAUMANN, 114,

120, 137, 139, 155, 364ABDERHALDEN andScHiFFMANN, 200,380ABDERHALDEN and SCHMIDT, 147, 381ABDERHALDEN and WERTHEIMER, 389Abderhalden's Reaction, 311, 312ABELS, 369, 380Aberi Acid, 21, 111Absorption, Assimilation, and Digestion

distinguished, 92Accessory Food Factor, Term defined,

22, 23Accidents that invalidate experimental

Results, 325Acetic Acid, see VinegarAcetonuria, 78, 80, 303Achlorhydria, 213Achylia, 267, 274, 286, 302Achtzig Stoffwechselversuche uber die

therapeutische Beeinflussung der ra~chitischen Stoffwechselstorung, 353

Acid Fermentation in Bowel, 77Acid-formers, Effect of Oxidation on

their biological Value, 94-99Acidosis, 41, 43, 44, 65, 66, 70-75, 76-

83, 84, 87-88, 90, 103, 104, 108,288, 294, 295, 296, 297, 298, 319,321, 322

defined, 80in malnutritional Oedema, 288, 294,

205in Osteomalacia, 234in Pellagra, 303, 319in Scurvy, 245, 269, 270in Sprue, 216, 217, 218

391

Acids—Effect on C, 259, 260, 264Effect on Walls of Bloodvessels, 288 »Excess of, see Acidosis

Acids and Acid-formers, excess of, incertain Nutrients, 70 et seq., 180,182, 2ii, 216, 217 ; see alsoAcidosis

ACKROYD and HOPKINS, 33, 355Acne, 76Acomplettinosis (terminology), 24Activation and Activators, 156, 158Active Tissues, 192Addison's Disease, 302Adenin, 117, 121Adenoids, 209ADKINS, 48, 376ADLER, 366Administration of Alkalies as a Pre-

ventive of Acidosis, 87-88Adrenalin, 86, 121, 122, 145, 146, 152,

153,154, 239, 240, 292, 294, 295, 297antagonised by Cholin, 295

Adrenals, 143, 144, 145, 146, 153, 201,204, 223, 238, 239, 240, 267, 273,285, 286, 287, 292, 294, 301, 302

Aetiologie der Beriberi, 341Aetiologie der Pellagra vom chemischen

Standpunkt aus, 338Agglutinin, 199AGAR, 160, 327, 332AGULHON and LEGROTJX, 363Ainos, Scurvy among, 242Air, Exposure to—

effect on Fat-soluble A, 187Alanin, 29, 31, 32, 33, 49Alanyl-glycin, 59ALBERT, 351ALBERTONI and TULLIO, 42, 313, 348ALBRECHT and WELTMANN, 286Albumiiruria, 300Albumose Poisoning, 75, 311Alcohol, 109, 195, 216Alcoholism, 76ALESSANDRINI, 306ALESSANDRINI and SCALA, 318, 319, 341,

347, 348, 349Alkalies ; see also Bases—

their Administration as a Preventiveof Acidosis, 87-88

their Effect on GrowtfMfi*ctor (B), 196their Effect on C, 256, 258, 204

Alkalosis, 78, 80Allan toin, 121ALLEN, B., see SHERMAN

392 VITAMINS

ALLEN, E, 364ALLEN, F P., see EMMETAlmond Oil, 221, 224, 331Almonds, 50, 191, 224, 244, 269, 329ALPAGO-NOVELLA, 307ALSBERG, 344Altstadt Hospital, 250Alumuiram Hydrate, 319ALWENS, 369, 383AMAND, 339AMAR, 38, 40, 363Amboceptors, 166, 199Amenorrhoea, 235America, see United StatesAmerican School, 323AMEULLE, 281, 378Amimsation, 167Ammo acids, st& also Tissue BuildersAmmo-acids, 121, 164 etseqAmmo acids, biological Value of, 29-36Ammonia, Formation of, 65, 73, 74, 75>

80, 81, 86, goSee also Acidosis

AMUNDSEN, 252Anaemia, 265, 267, 273, 300Anaesthesia, 286Anaphylaxis, 308, 310, 311Anasarca, see OedemaANDERSON, E, V, DUTCHER, ECKLES,

and "WILBUR, 385ANDERSON, A K , and FINKELSTEIN, 365ANDREWS, 344Animals—

Experiments on, Application of Resultsto Human Beings, 174

parasitic on Vegetable Kingdom, 240,241

ANREP and DRTJMMOND, 385Antibenbenn, 22, i nAntibodies, 243, 307, 308Antigens, 312Antineuntic Principle, see DAntiscorbutics, 243-262Apoplexy, 243Appetite, X43, 149, 200, 231, 276, 279,

299, 321APPLEMAN, 361Apples, 191, 209, 244, 251, 329APPLETON, 388Aracnin, 49, 58, 59Araciis hypogaea, see Earth nutArchangelsk, Scurvy m, 248, 249Argnun, 29, 31,33,121ARNETHS, 361ARNOLD, 96, 349; see also TEREG and

ARNOLDARNSTEIN, see EPPINGERARON, 14, 68, 185, 189, 190, 191, 199,

212, 231, 235, 246, 297, 336, 341,352,363,372, 378, 380

ARON and GRAUCA, 68, 335, 336,374, 384ARON and HOCSON, 103,155, 341, 342ARON and SAMELSON, 379Arrest of Growth, see GrowthArsenic—

as Remedy for Pellagra, 306is it essential? 67 et seg

Arthralgia, 265Artichoke leaves, 224

Artichokes, 330Artificial Feeding of Infants, see Breast-

feedingArum, 192, 224ASAYAMA, 355Aschamin, 120ASCHOFF and KOCH, W, 368ASFORD, 51, 341Ash, 64 et seq, 332 , see also Salts

total, Balance, 103, 130Asparagin, 29, 121, 290Asparagimc Acid, 29Aspergillus fumigatus, 307, 308Assimilation (Utilisation) must not be

confused-with Digestion and Absorp-tion, 92

Asthenia, see DebilityAsthenia, cardiac, 289, 297, 321Ata, 247Atomcity, see ToneAtrophy—

brown, 273in A deficiency, 239in B deficiency, 201m C deficiency, 267in malnutritional Oedema, 273, 284in Kehlnahrschaden, 296in IMilchnahrschaden, 297in "Vitamin deficiency, 143, 154.muscular, 147, T-57, ^seqNerve, in Pellagra, 300

Atropin, 122, 144A/TWATER, 39, 40Auditory Nerve, Affections of, in Pel-

lagra, 300AUER, 232, 364.AULDE, 74, 241, 380Autoclave, 197, 229Autointoxication, 281Autolysis, 114, 120, 121, 136, 186, 187,

Autolytic Poisons, 243Avitaininosis (Terminology), 23, 24Azoospermia in Vitamin Deficiency, 143

B, water-soluble {see also Growth-factor),22, 136, 138, 139-142, I44-, 160,161, 187-201, 216, 218, 222, 226,227, 228, 230, 231, 235, 236, 239,246, 249, 256, 262, 265, 275, 283292, 294, 295, 296, 298, 514., 317,322, 333,334, 335,336

confounded "with A, 222, 226confounded-with D, 195-196historical, 187—191Occurrence, 191—194.physiological Effects, 198—201Properties, 195-198quantitative Estimation, 194—195

BABES, 306, 359BABES and JONESCU, 311, 350BAXCELLI, see XuiBACH, 365BACHMANN", 194, 369, 378Bacon, 249, 280

salt, 251Bacterial Flora of Intestine, see FloraBAGUONI, 42, 43, 45, 313, 350, 352

INDEX 393Balance, nitrogenous, etc. See Nitro-

genous, etc.Balkan War, Scurvy during, 247Banana Protein, 140, 176, 178Bananas, 50-51, 54, 55, 66, 140, 182,

186,191, 224, 251, 329BANG, 32, 286, 354, 363JBANGNESS> see MCCLENDONBarcelona Nuts, 224.BARGER, 349Barley, 46-47, 138, 176, 181, 186, 191,

223, 247, 253, 329BARLOW, 338BARNES and HUME, 233, 253, 255, 257,

261, 365, 369BARR, 77, 91, 103,104, 145, 293BARSICKOW, 119, 34.7BARTENSTEIN, 339Bases, see also Alkalies

Deficiency of, 53, 73, 199, 247, 268,296, 298, 317, 318, 321, 322

Excess of, 56, 58, 64, 65, 66, 70-75,140, 180, 182, 183, 209, 217, 241,261, 262, 270, 321, 323

in organic combination, 90supply of, 58

BASS, 306, 343 ; set also WELLMANBASSET-SMITH, 260, 377, 379, 387BAUMANN" and HOWARD, 345, 358BAYLISS, 78, 370.Bean Flour, boiled, 305, 314Beans (see also Haricots, Katjang-idjo,

Leguminosae, Soy Beans), 48-49,55,133,175, 191,196, 223, 249, 280, 328

fresh, r 06, 328germinated, 248, 249, 328green, unripe, 252

Beef—corned, iorfat, 222, 225, 331lean, 138Suet, 236

BEESOIST, 380Beet, Sugar, 192, 224Beetroot, 192,224, 252,330BEGER, see MORG-ENBEGUN, HERRMANNT, and M^NZER, 79,352B enamour of the Glands, 142-146BEHRE, 379BEHRINTG, 311BENEDICT, F. G., 60, 370BENEDICT and ROTH, 73, 351BENEDICT, S, R., see SUG-IURABENINDE, 371Benno-Schilde Company, 261Benzoic Acid, 236BERG, 9, 10, 11, 12, 13, 14, 15, 18, 19,

28, 41, 48, 51, 53, 58, 60, 61, 62,65, ?o, 7i, 73, 75, 76, 84, 85, 86,89, 90, r8i, 34.0, 342, 345, 347, 348,357, 364, 388 ; see also BIRKNER,ROSE

BERGMANN, 206, 365Beriberi, 77, *74, 245, 254, 264, 273, 283,

292, 299, 314, 347acute cardiac, 131and other forms of Polyneuritis, roo-

T71 (for Details see Table of Con-tents, Chapter Four), 333

Beriberi (continued}—dry, 130Etiology, 100—109,124fulminant, 272latent, 162ship, 109, 279—281wet, 130, 131, 271

Berkefeld Filter, 306Betain, 121, 122,123BEZSSONOFF, 383, 385BEZZOLA, 310, 340BIDAXJLT and COUTURIER, 119, 379BIERICH, 246, 368BlERRY, 38, 365 369BlERRY and PORTIEH, 78, 361B I E R R Y , PORTIER, and RANDOIN1 , 143,

153, 3/7BIESTER, seeDutchex, WheelerBlGLAND, 279, 282, 315, 316, 371, 375Bilberries, 215Biogenen Amine, etc., 370Biological Value—

of Acid-formers, the Effect of Oxida-tion on, 94-99

of animal Proteins, 52-58of various Proteins, 29—61, 327of vegetable Proteins, 41-52 ; see also

Protein, Importance ofBiophor, 22B I R K N E R , 75B I R K N E R and BERG-, 347Biscuit, 249, 252, 268, 305, 315BISHOP, see EVANSBleaching of Vegetables, 211 , 247, 261,

262, 278B L E N C K E , 373B L I E C K and BAJUDET, 369Blindness, 297BLOCH, 233, 357, 362, 383BLOCK, 211, 212, 380Blood—

(as Nutrient), 178-count, 274-pressure, 142, 144, 154, 2.72, 273, 285,

289, 292, 295, 297, 303, 304Protein, 53, 178self-regulating Power of, 81 , 83-serum, 53, 269, 310, 311, 312

BLOOMBERGH, see CHAMBERLAINBLUM, 379B L U N T and W A N G , 383BOAS, see MCCOLLUMBody—

Temperature, see TemperatureWeight, see Weight

Body-fat, 185, 222, 223BOGEL, see VERZARBoiling—

effect on. A, 219, 229effect on. B, 196effect on. C, 244, 249, 257-262effect on Vitamin, 118 et seq.f 124, 125of Vegetables, effect on Base Content,

of Vegetables -with subsequent Rejec-t ioa of Water , 73, 125, 171, 183,217, 249, 262, 278, 283

unduly prolonged, 249, 250,^78, 283BOLDVREFT, 358

394 VITAMINS

BONAR, see PHEMISTERBone, Diseases of, see OsteopathyBONNE, see KOCKBORDONI, see VOLPINOBORTJTTA.N, 42, 363, 37O, 378BORY, 375BOSSERT, 76, 294, 371BOSTOCK, 139, 347BOSWORTH and BoWDITCH, 357Bottle-feeding, {see also Breast-feeding),•r, 255

BOTTOMLEY, 355, 356BOUTWEIX, see STEENBOCK:BOWDITCH, see BOSWORTHBOWERS, see MCCLENDON-BOYD, 41, 45, 48, 54, 58, 61, 307, 313,

316, 320, 377BRADDON, 339BRADDON and COOPER, 349, 350Bradycardia, 273, 289Brain—

as Food, 139, 193, 195, 196, 328changes in Polyneuritis, 142, 143

BRAMMERTZ, see ABDERHALDEKTBran, 45, 51, 59, 111, 113, 189, 191, 200,

223, 247, 253, 328. (See also RiceBran.)

BRANDT, see MILLERBRAVETTA, 315, 316, 374Brazil Nuts, 224.Bread, 196, 244, 249, 250, 251, 253, 278,

280, 283, 320, 328, 329baking of, 196white, 101,106, 124, 125, 328wholemeal, 328

Breast-feeding, Advantages of, 206, 207,231, 238

BREAUDAT, 103, 343BREEST, 319, 380Brief Experiments, see DurationBritish Medical Association, 236, 317British Navy, Antiscorbutics in, 243BROWN, M. A, 172, 370BROWN, W. L., 383BRUDZINTSKI and CHELKOWSKI, 351BRTJGSCH and KRANS, 212BRUNTZ and SPILLMA,**, 51, 363Bucco, 105, 378BUCKNER, N"OLLATJ, and CASTLE, 351BUCKNER, NOIXATJ, WILKINS, and

CASTLE, 41, 46, 366BUELL, see STEENBOCKBuffer Salts, 79, 81Bulgarian Army, Scurvy in, 247Bulimia, 299BULL, 360BULXEY, 232, 364, 367BCRGER, 273, 275, 276, 277, 278, 282,

283, 284, 367, 378Butter, 185, 187, 209, 211, 220, 221,222,

223, 224, 225, 229, 230, 233, 236,283, 297, 320, 327, 33i, 332, 333,335

superheated, 221, 229Buttermilk, 232, 233, 331Butternuts, 224Butter-and-Flour Preparation, 298Butyric Oil, 185, 222, 227, 228, 230BYFIELD, 139; see also DANIELS

BYFIELD, DANTIELS, and LOUGHLIN, 196,334> 376

C, water-soluble (antiscorbutic), 22,159160, 210, 2ix, 217, 227, 228, 235,242-270 (for Details see Table ofContents, Chapter Seven), 296, 322,333, 334, 335

Animals cannot synthetise, 253Cabbage, 118, 119, 192, *96> X97, 224,

225, 229, 244, 251, 330boiled, 2.57, 258, 330dried, 224, 229, 244, 258,259, 260,330pickled, 248, 330white, 192, 224, 251, 257> 33°juice, 257, 258, 261

Cabbage Water as Source of nutritiveSalts, 90

Cachexia, 300, 301,321Cage Factor, 25CAJORI, 50, 193, 380Calcium, 55, 87, 88, 91, 209, 218, 241,

274Balance, 93, 94, 103, 267, 275, 303, 318Carbonate, 319Chloride, 319Deficiency of, 43, 69, 70, 71, 72, 74,

140, r8o, 181, 182, 184, 205, 209,218, 234, 235, 237, 241, 247, 268,282, 294, 295, 296, 298, 318, 322

Demand for during Growth, 180,181Embryo may rob Mother of, 72Ions and Oedema, 287-288, 293-295Metabolism, 93, 287-288Requirements, 62Xerophthalmia and, 241

Calcium Salts—injection of as Remedy for Scurvy, 269their paradoxical Effect, 83-87their stimulating Influence on endo-

thelial Activity, 288, 290urinary Excretion and, 290use in malnutritional Oedema, 277utilisation of, 180utilisation in various forms of Admin-

istration, 92—94Calories (see also Energy)

deficient Supply, aggravates Scurvy,267

deficient Supply, in re la t ion to m a l -nut r i t iona l Oedema, 277, 281, 282

in pellagrogenic Die t , 305, 315CAMPBELL, H . 1 . , see M E R , S H E R M A NCAMPBELL, M. E . D . , and C H I C K , 363CAMURRI , 307, 343Cancer, 201, 216Cancer Hospital Research Inst i tute , 77Canning, 125Carbohydrate D i e t —

in relation t o Acidosis, 77 , 78in relation to malnu t r i t iona l Oedema,

277, 282excess of, accelerates onse t of Poly-

neurit is , 118Carbohydrates—

as Nitrogen Economisers, 39manufactured from Prote ins , 37

C A R B O N S and CA.ZZAMA.LLI, 308, 348

INDEX 395Carbonic Acid, free, as cause of hyaline

Degeneration, 288Carbonic-Acid Tension in Alveoli, 79, 80Careace, 10, 14Careace fruste, 14Carence, Maladies de, 10, 24Caries, dental, 209, 248, 266CARLETTI, 307, 312, 343 ; see- also

LUCA/TELLOCARNEIRO, 347Carnivora, supplementary Vegetarianism

in, 58Carolina, Pellagra in, 307Carotin, 228Carpopedal Spasms, 76, 294. Set also

TetanyCARREL, 163, 164.Carrot Juice, 211Carrots, 50, 51, 55, 66, 92, 93, 94, 137,

176, 178, 182, 186, z8g, 192, 196,197, 21/, 224, 225, 244, 252, 277,290, 330

boiled, 257, 33Odried, 244, 258Extract of, 252Juice, 330

CARRUTH, sec WITHERSCARV, 380Casein, 34, 43, 45, 46, 48, 50, 57, 53,

54, 55-56, r.40, 178, 186, 194, 197,221, 222, 230, 277, 332, 334

CASTILE, see BUCKNERCatabolism, 171Catalase, 147, 148, 158, 159, 171, 263Cauliflower, 330Causes and Prevention of Beriberi, 339CAZZAMAIXI, see CARBONECAZZANI, 358Celery, 330CENTANNI arid GALASSI, 3Z3, 318, 347Cereals, 41-47, 176, 178, 181, 183, 185,

186, 187, I91, 2O9, 2IO, 211, 217,232, 241, 244, 252, 253, 269, 278,296, 327, 328, 329

unsuitable Food for growing Animals,181, 296; see also iinder specificnames, as Wheat, Maize, etc.

CESSNA, see NELSONCHACE and MYERS, 374CHAMBERLAIN, 342, 352CHAMBERLAIN, BLOOMCBERGH, and KIL-

BOURNE, 102, 132, 342CHAMBERLAIN and VEDDER, 102,120,342CHAMBERLAIN, VEDDER, and WIILIAMS

116, 343Chamberland Filter, 256Charcoal as Roughage, 190Cheese, 222, 331Chemie der Zerecdien, 354Chestnuts, 191, 329Chicago experiences, 209CHICK, 211, 238, 249, 372, 374, 379 ; see

also CAMPBELL, DAL\TILL, HOPKINS,HUME

CHICK and DALYEZ,L, 176, 373, 380CHICK and DELF, 367CHICK and HUME, 119, 248, 315, 357,

368, 374 ; see also HUME and" IICK

368,CHIC

CHICK, HUME, and SKELTON-, 253, 340,360, 361, 368

CHICK and RHODES, 361Chicken Fat, 225Children, Feeding of, 172 ei seq., zog-

2x2, 250Chinin, 121, 122Chinolinic Acid, 123CHITTEN-DEN and UNDERHILI,, 305, 314,

357Chlorine Ion—

effect on. Kidney, 290paralysing Influence of, 276, 290, 293-

295Chocolate, 252, 268Cholesterin, 204, 221, 274

Impoverishment, 285-287, 288Cholin, 113, 121, 144, 145, 204, 295

the natural Antagonist of Adrenalin,295

CHRISOSTOMO, 350CHRISTMANN, 357CIACCIO, 371Cinchoraeronic Acid, 123Cinchonidin, X21Cinchonin, 121, 122Citrates, 246Citric Add, see LemonsCitrozinic Acid, 123Citrus, 251Civilisation, 205CLAIR, 105, 373CLARK, A. B., see STEPHENSONCLARK, E., 203, 352, see VEDDERCLATPON, see LANJE-CLAYPONCLEMENTI, 106, 304, 354Clover, 192, 200, 224, 252, 330, 332Cocoanut, 50, 329

Cake, 191, 224, 329Oil, 185, 224, 225, 331

Cocum, 329Cod,225Codliver Oil, 147, 185, 211, 221, 223,

225, 229, 233, 235, 236, 237, 331phosphorated, 235

Co-enzymes, 147, 154, *55, *59, 166COHEN, see GIVENSCOHEN and MENDEL, 246, 253, 362Coffee, 250

Substitute, 251COLE, see MCCLEN-DONCOLLATZ, see DUTCHERCOLLODI, 306, 341Colloids, 198Coma, diabetic, 79, 88Commandeering by Foetus, see Milk,

secretion ofComplement Activity, 199

Deviation of the, 308Formation, 311

Complettin Content of Foodstuffs, 326-33i

Experiments, Nutrition in, 327, 333-336

Complettin, term defined, 22COMRIE, 248, 249, 374Conarachin, 49CONCEPTION, see GIBSON, GTJERREROConclusion, 323-337

396 VITAMINS

Condensation, of Milk, see MilkConditions of growth, 172-218Conditions requisite for Efficiency of

various kinds of Protein, 58-61Congestion, passive, 272, 285, 293, 295Conglutin, 48,176CONKLIN, see MATTILLConsequences of Insufficiency of Vita-

mins (Funk's)—(a) clinical, 126-128(b) pathological anatomy, 128-129(c) the Forms of the Disease, 130-

132Constipation, 245, 246, 279, 299 ; see

also RoughageConsumption, 243Contractures—

cicatncial, after Scurvy, 266spasmodic, see Tetany

Control experiments, 60, 72, 136, 201Cooking Salt, see Sodium ChlorideCOOPER, 109, 1x7, 122, 129, 137, 346,

34-7, 348, 349, 386 ; see alsoBRADDON

COOPER and FUNTK, 343COPEMANT, 201Copper, 67 et seq., 332CORNALBA, 358Cornea, IJlceration of, see Keratoma-

laciaCorned Beef, see BeefCottonseed Oil, 186, 187, 224, 225, 3°5>

314, 33iCouirs, 36rCOUTURIER, see BIDAULTCOWARD, see DRUMMOND, ZILVACOWARD and DRUMMOND, 376, 388COWGILL, 383, 387, 388Cotton Seeds and Cottonseed Meal, 43,

49, 50, 107, 176, 178, 182, 185, 191,253,329

Proteins of, 55, 182Toxicity of Meal, 67

COWGILL and MENDEL, 388Cox, see LEWISCRAMER, 145, 374, 379CRAMER, DREW, and MOLTRAM, 387CRAMER, and SCHIFF, 381Cramming, 132, 143, 333Cranberries, 70Cream, 147, 222, 233, 297, 298, 331

University, 236Cress, 330CRONHEIME, 341CROWELL, see STRONG, WILLIAMS, R. RCryoscopic conditions, 289Cucumbers, 251, 330CULLEN, see SLVKECURJEL, see GREIG-Curry, 216CUTLER, see ROBERTSONCyclopoiesis, 31, 34, 156,157, 167, 262Cynuric A.cid, 34Cystein, 29, 30, 31, 95,168, 269Cystin, 29, 31, 34, 4-7, 49, 53, 54, 56, 57,

59, 95, 96, 168, 176, 177, 180, 296,322

CZERNTV, 298CZERNV and KLEINSCHJIIDT, 298

D, water-soluble (antineuritic), 136, 138,139—142, 159, 160, x6i, 162, 164,165, 166, 170,194, 197,200,204,218,228, 239, 262, 322, 333,334, 336

confounded with B, 195-196, 197confounded with Funk's Vitamin, 333

DAHLE, see DUTCHER.DALYELL, 211, 231, 235, 379DALYELL and CHICK, 388DALYELL and STILL, 255DAMIANOVICH, 388, 389; see also

MATHEWDandelion, 244, 251, 257

dried, 244, 258Leaves, 330

DANIELS, see BYFIELDDANIELS, BY-FIELD and LOTJGHLIN, 366DANIELS andLOUGHLIN, 49, 360, 375,381DANIELS and MCCLURG, 118, 119, 365DANIELS and NICHOLS, 49, 66, 359DARLING, 350Dasheens, 330DAVEV, 384DAVIS, D J , 358, 361, 3 5,388DAVIS, M, and others, 373DAVIS, M, and OUTHOUSE, 387DAWSON, see SULLIVANDebility, 200, 231, 239, 268, 279, 299,

305Deficiency Diseases, 24Deficiency in Diet of Parents may affect

Offspring, 72, r74, 189, 204-207Degeneration, hyaline, 270, 271Degeneration, so-called, as an Outcome

of parental dietetic Errors, 174, 204-207

DEHIO, 370DELF, 14, 189, 229, 257, 260, 264, 364,

374, 375 ; see also CHICKDELF and SKELTON, 230, 259, 261, 364DELPRAT, see ROBERTSON*Denaturation of Food, 220,246DEN-TON and KOHMANN, 182, 277, 282,

363DESGREZ and BIERRY, 374Dermatitis—

in, Pellagra, 299, 300, 305, 308,309,321in Scurvy, 266

Determinants of Growth, see Growth-Factor

Deviation of the Complement, 308DEVLOR, 339DEZANI, 221, 350DIABETES, 76, 77, 78, 79, 88, 239Diarrhoea, 200, 283, 299, 300, 305Diathesis, haemorrhagic,

see HaemophiliaDICK, see MCCLENDONDlCKENSOiN, 109, 351Diet, Analysis of its Constituents

essential, 91Diet—ill-balanced, 126, 132, 151, 159,

232,276, 281, 282, 304, 305,315monotonous, 221pathogenic of malnutritional Oedema,

277, 278pellagrogenic, see Pellagraremedial in Pellagra, 320-322rigid, 126

INDEX 397Dietetic Errors in Parent, their Effect

may be first noticeable in Offspring,72, 173, 174, 175, 204-207

Dietetic Errors leading to Arrest ofGrowth, 208

Dietetic Experiments, their Difficulties,324-325

Dietetic Test, see TestDifferences between Polyneuntis and

Starvation States, 148-153DJLfferences between water soluble B and

water-soluble DDifficulties attendant on dietetic Experi-

ments, 324-326Digestion, Absorption and Assimilation

distinguished, 92Disaminisation, 169, 170Discussion on the present Position of

Vitamins in Clinical Medicine, 236,317

Diuresis, 292, 294, see also PolyuriaDizziness, 299, 3roDODD, 346; see also TALBOTDONALDSON-, H. H, 365DONALDSON, J C, 365DOTSCH, 339DOUGLAS, see FUNKDOWNS and EDDY, 389DREIFUS, 77, 372DREW, see CRAMERDRIEL, 143, 375Dnpping, 185Dropsy, see OedemaDrugs that cause basic Deficiency, 73DRUMMOND, 22, 44, 138, 185, 188, 189,

193, 198, 199, 200, 228, 229, 240,247, 354, 357, 360, 366, 376, 383,388 ; see also ANREP, COWARD,HALLIBURTON, HOPKINS, ROSEN-HEIM, ZlLVA

DRUWMOND and COWARD, 229, 376, 382,DRUMMOND and PUNK, 112, 350, 361DRUMMOND, COWARD, and WATSON, 388DRUWMO»ND, GOLDING, ZILVA, and

COWARD, 382DRUMMOND and WATSONDrying of Foodstuffs, Effect on B, r gj

Effect on C, 245, 2S8-262Dryness of the Cornea, see XerophthalmiaDUB IN, see FUNKDUB IN- and LEWI, 372DUBOIS, 7S, 361Ductless Glands, see EndocrineDUFOUG-ERE, 109, 379DUNHAM, 384DuRANr>, 356Duration of Experiments, 18, 35, 36, 41,

65. 72, <A 173, m , *77D<JRCK, 128DURHAM, 103, 155, 339DURLACII, 99, 346BUTCHER, 146, 14.8, 252, 368, 370, 387,

see also ANDERSON, FIERSONBUTCHER and COIXATZ, 148, 362, 363BUTCHER, ECKIXS, DAHLE, MEAD, and

SCHAEFER, 255, 382BUTCHER, HARSH AW, and HALX, 387BUTCHER, KENNEDY, and ECKLES, 373BuTCHER,PiERSoar,and BIESTER, 252,377

DUTCHER and WILKINS, 388DYKE, 361Dysentery, 283

EARTH-NUT, 45, 49, 160, 191, 223, 329Oil, 236, 331, 333

ECHOLS, see TANNERECKLXS, see ANDERSON, BUTCHER,

PALMERECZEMA, 300; see also DermatitisFDDY, K. B , see DOWNSEDBY,W H 138,198,356, 357,372,384EDEV, HEFT, STEVENSON, and JOHNSON,

386EDDY and ROPER, 357EDDY and STEVENSON-, 139, *4** 37i, 378EDELSTEIN, see LANGSTEINFDELSTEIN and LANGSTEIN, 54, 365Edcstin, 43, +9, 56, 98,176, 332FDIF, ser SIMPSON*EDIE, EVANS, MOORE, SIMPSON-, and

WEBSTER, 103, 113, 344Effect of Oxidation on biological Value

of A.cid-formers, 94-99Effects of Punk's Vitamins, 136-139Egg Albumin, see OvalbuminEgg Fat, 331Egg Plant, 330Eggs, 52-53, 55, 176, 192, 209, 223, 233,

255, 268 315,320, 328are rich in P unk's Vitamins, 124raw, 294., 295their To-xicity m Acidosis, 76White, set WhiteYolk, see Yolk

Egypt, Pellagra in, 316, 320Egypt, Prison Dropsy in, 279EHRLICH, 97, 338ElJKMAN, IO2, 129, 148, 338, 339, 343,

348, 354, 362EIJKMAN and HOOGENTHUVGE, 355EIJKMAN and Hui SIIOFF-POL, 363Einfiuss des Abbruhens anf den Nahrwen

unserer Gemusekost, 342Einwirkuns von Erdsalzen itsw auf

A usscnetdung, and Zusammen-settling des Hams, 343

EISLER, 369EKEUJF, 105, 243, 339EL KANTARA, 316ELIAS, 76, 360ELLIS, N. R, see HARTELLIS, N\ R, STEENBOCK and HART,

385ELLIS, "W*. G , 341Emaciation, 78, go, 98, 102, 126, 132,

134, 135,136, 137,148,149,150, *&o.r6i, 178, 199, 208, 2x3, 230, 231,239, 265, 267, 273, 297, 300, 305, 321

Embryo, see GermEMMET, 90, 373, 386, 387EMMET and ALLEN, 367EMMET, GRINDLEY, JOSEPH, and

WILXIAMS, R H., 348EMMFT and JLUROS, $6, 141, 366, 367,EMMET and MCKIM, 116, I36,"359EMMET and STOCKHOLM, 14.1, 194, 378

398 VITAMINSEms Water, 215Endocrine Glands, 35, 201-204, 235

239-241, 267, 292, 301, 302; see alsoGlands

Endosperm of Maize—its low nutritive Value, 314

Endosperm, Growth-factor in, 140Endosperm, Value as Nutrient, 42, 43,

45, 46, 223, 328Vitamin. Deficiency of, 124,125

Endothelium, secretory Activities of,287-288, 293 ei seq

Energetics of the Muscular System, 146-148

Energy, Diet as Source of, 179, 326, 327 ;see also Calories

ENGSTRAND, see MCCLENDONENRIGHT, 316, 320, 371, 377Enzymes (see also Co-enzymes), 166, 171,

243, 263, 264Epilepsy and Epileptiiorm Convulsions,

76Epipayses, Separation of, 266Epistaxis, see NosebleedEFPINGER and ARNSTEIN, 345EPPINCER and ULLMANN, 380EPSTEIN, 361Erdsalzarmut and Entartung, 339Erganzungskorper, 22ERLACHER, 385Errors of Diet, set Dietetic ErrorsEskimos, Scurvy among, 242ETIENNE, 86, 345ETIEN-NE and FRITSCH, 86, 340EULER and PETTERSSON, 384, 388Europe, Western, Scurvy in, 249EUSTIS, see WELLMANEUSTIS and SCOTT, 350EUTONINS, 22, 137EVANS, H. M, and BISHOP, 389EVANS, W. H., see EDIEEWALE, see ABDERHALDENEWING, see WELXSExcelsin, 50, 176Experimental Stations Office, 62, 336Experiments, "brief, see DuratioaExperiments, Control, see ControlExperiments, Duration of, see Dura-

tionExperiments on insufficient Nurnbei of

Animals, 190Exudation into Tissues, see InfiltrationEve Troubles of Roumanian Children,

386N, see EIJKMAN

FABER, 377, 381, 388Faeces, Vitamin in, 163, 325FAHRION, 375TALK, 369FALTER and QUITTNER, 358Famine Dropsy, see Oedema, malnu-

tritionalFANDARD, see RANDOIN-FANDARDFARGIER, 345Fat, Intolerance of, in Milchnahrschaden,

297Fat-soluble A, see A

Fats, 186, 187, 189, 327, 33i ; see alsoBody-fat, and Storage-fat, andspecific Fats

Fats as Nitrogen Economisers, 38, 39Fats as Tissue Builders, 37, 38Fats, hardened, 225Fats in Infant Feeding, 296-298Fats, Ingestion of, in Relation to

Acidosis, 77, 78in Relation to Malnutritional Oedema,

277, 282, 283, 286Fats manufactured from Proteins, 37, 40FEIGH, 273, 274, 289, 361Fermentation in Bowel, 104, 214, 215,

245, 246, 296, 3°3, 3*3Ferments, see Enzymes, Co-enzymesFERRY, 382 ; see also OSBORNEFEUILLE, 82, 364FIBRIN, 53FIGUEIRA, rip, 200, 245, 255, 372FILDES, 383Filter Paper, 160, 190, 333, 335FINDLAY, G. M., 340, 382, 384, 387FINDLAY, L., see PATONFINDLAY, L., PATON and SHARPE, 385FINE, see MYERSFINGERLING, 63, 97, 343FlNKELSTJEIN, See ANDERSONFINKS, see JOHNSFINKS and JOHNS, 386FISCHER, 29, 59FISH, see HESSFish (see also specific Fish, e.g. Pike,

Cod), 57, 139, 327, 328dried, 242fresh, 248Fat, 223, 328lean, 328Oil (see also Codliver Oil, etc.), 185,n 223, 331Roe, 328smoked, 242

FISHBACK, see HAWKFlat-foot, 209FLATHER, 364FLEMING, 388FLETCHER, 143Flora, intestinal, 189, 198, 234, 245, 246,

303FLORENCE, 269, 376Hour, 186,249, 280, 328, 329Flour, white, 101, 106, 183, 296

"wholemeal, 280Fluorescence, 309, 310Fodder, 234

<ky> i94» 226green, 194, 318lactation and, 194, 207

Fodder Pea, 48-49Fodder, seasonal Variations in, 225, 226,

253, 255Fodders, natural, 192FORBES, HALVERSON, and SCHXJLZ, 70, 84,Forced Feeding, see CrammingForms of Combination of Inorganic

Substances, 88-90Fragility of the Tissues, 270FRANCHETTI, 374

INDEX 399FRANCIS, C. K, andTROWBRiDGE, 170,341FRANCIS, E., see LAVINDERFRANK, A., see FREISEFRANK, L., and SCHLOSS, 348; see also

SCHLOSSFRANK, M., 370FRANKEL and SCHWARZ, 114, 382FRASER and STANTON, IIO, 132, 133,143,

155, 340, 341, 342, 345, 348, 352Frederick the Great Orphanage, 250, 261FREISE, 177, 264, 350, 370FREISE, GOLDSCHMIDT, and FRANK, R.,

232, 233, 352French Beans, 328Fresh Nutrients, natural Craving for in

Scurvy, 268FREUDENBERG, 349FREUDENBERG and GYORGY, 147, 380FREY, 82, 364FRITSCH, see ETIENNEFROLICH, 253, 257, 340, 344Fruit (see also under specific Names (as

Orange, etc.), 209, 215, 217, 218,247, 327

dried, 251, 329fresh, 244, 246, 248, 251, 268, 269is poor in A, 224is rich in water-soluble B, 191juice, 251, 256raw, see Fruit, freshsalt-rich, 209

Fuel, Food as, 151FUHGE, 84, 86, 366FUHNER, 380FUJITANI, Il8, 34IFULLER, see HARTFULMER, see NELSONFULMER, NELSON, and SHERWOOD, 194,

384FUNGI, certain, cannot synthetise A, 240,

241FUNK, 9, 10, 12, 13, 21, 22,23, 77, 104,

no, in , 112, 113, 114, 116, 117,118,120,121,122, 123,134,135,136,138; *39, 142,156,159,161,181,187,198.199, 200, 202,204, 226,239, 245,246, 247, 264, 269, 284, 313, 314,316, 317, 333, 336, 341,342,343,344,346, 347, 348, 349, 350,352,353,354,369,387: see also COOPER, DRUMMOND

FUNK and DOUGLAS, 349FUNK and DUBIN, 373, 381, 388FUNK, LYLE, and MCCASKEY, 52,175,356FUNK and MACALLUM, 52. 142, 198, 221,

226, 228, 349, 352, 356FUNK and POKLOP, 355FUNK and SCH6NBORN, 104Funk's Vitamins (antineuritic), see

Chapter Four, passim, 187, 188,194,198.200, 201, 218, 220, 226, 228, 239,245, 246, 247, 255, 264, 275, 283,315, 3i6, 317, 325, 333i 334> 335, 33$

confounded with D, 333FURST, 244, 245, 264, 268, 340, 343, 344FORTH and NOBEL, 54, 381

GAERTNER, 377GALASSI, see CENTANNIGALMOZZI, 303, 376

GARRISON, see SILERGastralgia, 279, 299Gastro-intestinal Disorder as exciting

Cause of Beriberi, 126Gastro-intestinal Disorder—

in B Deficiency, 198in C Deficiency, 267in malnutritional Oedema, 274, 278

281, 283in Mehlnahrschaden and Milchnahr-

schaden, 296-298Gastro-intestinal Disorder in Pellagra,

299, 30°, 301, 302, 311Gastro-intestinal Disorder in Ship Beri-

beri, 279Gastro-intestinal Disorder in Sprue, see

SprueGATTI, see VIDONIGefahr einer an Kaliumverbindung xu

armen Ernahrungsweise und ihreBeziehung zu Erndhrungskrankheiten,

r* 354

GEILING, 33, 359Gelatin, 45, 46, 58, 176, 269GELLHORN, see ABDERHALDENGERARD, 82, 345Germ (of seed), biological value as

Nutrient, 42, 45, 191A content of 223, 225,removal of, 210, 211rich in Funk's Vitamins, 124WheaVsee Wheat

German Prisoners, Pellagra among, 316Scurvy among, 248, 249

German Society for Tropical Hygiene, 280Germinated Beans and Peas as anti-

scorbutic, 248, 249Effect of Boiling, 258, 261Effect of Drying, 261

Germination—of Beans promotes their Digestibility,

48, 59of Seeds develops antiscorbutic

Principle, 245, 255-256GERSTENBERGER, 387GIBSON, 347, 354GIBSON and CONCEPCION, 348Gigantism, 203GIVENS, see HUNTERGIVENS and COHEN, 227, 260, 362GIVENS and MCCLUGAGE, 258, 239, 260,^ 365, 372, 376, 384GIVENS, MCCLUGAGE, and HORNE, 383GIVENS and MACY, 384Glands—

Behaviour of, 142-146, 153, 154, 201-204, 218, 267, 297, 333

Glands, endocrine, see EndocrineGlaucoma, 281Gliadin, 45, 46, 55, 176, 3*3Globulin, 50, 176GLOGNER, 341, 343Glutamic Acid, 29, 31Glut am in, 29Glutazin, 123Glutelin, 43, 176Gluten, 178, 315

Maize, 178, 315Glutenin, 43, 45

400 V I T A M I N S

Glycogen, 273; see also Hyperglycaemia,and Hypoglycaemia

Glycyl-alanin, 59Glycocoll, 29, 31, 33GODLEWSXI, 385Goitre, 319GOLDBERGER, 35O, 356, 362GOLDBERGER, WARING, and WILLETS, 35 2GOLDBERGER and WHEELER, 305, 316,

318, 352, 373, 376GOLDBERGER, WHEELER, and SYDEN-

STRICKER, 315, 317, 362, 374, 377GOLDFLAM, 381GOLDING, see DRUMMOND, ZILVAGOLDSCHMIDT, see FREISEGooseberries, 215Gosio, 312, 350GOXJZIEN, 345GOY, 384GRABER, 382GRABLEY, 91, 369Grain diet, exclusive, 70, 73, 74-

supplemented with, green Fodder, 182GRALKA, see ARONGraminivorous Birds require green Food

also, 182Graminivorous Birds, their Young are

carnivorous, 181Grains, see Seeds, CerealsGrape Juice, 251, 329Grape-fruit, 224, 329Grapes, 329Grass, 192, 330

dried green, 25 3GREEN, 362; see also RICHARDSONGreen Parts of Plants contrasted with

Seeds as Nutrients, 182, 252Green Parts of Plants as source of A, 240Green "Vegetables, 124,133, 186,189,192,

222, 224, 227, 251, 269, 318, 330Greenness of Vegetables and Fruits, their

Richness in C proportional to, 251GREGERSEN, 98, 342GREIG, 359, 361GREIG and CURJEL, 360GRIJNS,339, 340,343GRIMM, see LAVINDERGRIND LEY, see EMMETGROSS, see STEENBOCKGROSSER, 96, 346Growth {see also Growth-Factor)

Arrest of, 199, 204, 208, 226, 230, 231,239

Growth, Conditions of, 172-218, 334Inhibition of, Effect on subsequent

growth, 207-209Maintenance of, 179, 181, r82, 207,

222, 223Normal, dependent on Diet, 209 et seqStimulation of, 200

Growth-factor {see also B, water-soluble,and A, fat-solufcle), 138, 139, 140,141,142,144-, 172-218, 219-222,224,334

Tiel, :Gruel, 294, 295,296GUAZON, see MENDOZA-GUAZONGuanin, 121GUERRERO and CONCEPCION, 371GUGGENHEIM, 370

GUILLAIN, 376Gums, scorbutic Affection of, 265, 265GURBER, 358GUTMAN, see HESSGVORGY, see FREUD ENBERG

HAAN, 341Haematemesis, 279Haemoglobin Richness, 231, 267, 274Haemophilia, 160, 242, 265, 266, 267, 284Haemorrhages, see Scurvy, passimHaemorrhagic Diathesis, see HaemophiliaHaemotoxin, 281Hair, 200HALL, see DUTCHERHALLIBURTON, 221, 361, 382HALLIBURTON and DRUMMOND, 357HALPIN, see HARTHALVERSON, see FORBESHAMSHIRE and HAWKER, 236, 367,Handbuch der allgemeinen Therapie, 212HARDEN, 383 ; see- also HOPKINSHARDEN and ROBISON, 365, 368, 374, 388HARDEN and ZILVA, 123, 527, 246, 256,

260, 268,357,360,363, 364, 3^6, 368,374, 386

HARDEN, ZILVA, and STHX, 364Hardening of Fats, 225Haricot Beans, 48, no , 118,119, 175,182

328HARLEY, see JACKSON, P. G.HARRIS, R. H., see DUTCHERHARRIS, S., 316, 372HARRIS, H. C, 306, 348HARROW, 9, 12HARSHAW, see DUTCHERHART, C, 344, 345HART, E. B., see ELLIS, N. A.,STEBN-

BOCKHART, HALPIN, and MCCOLLUM, 66, 106,

108, 357HART, HALPIN, and STEENBOCK, 43, 44,

181, 190, 359HART, HALPIN, STEENBOCK, and JOHNSON

0. N., 380HART, HALPIN, and SURE, 359HART, HUMPHREY, and LEPKOWSKY, 381HART and MCCOLLUM, 42, 44, 52,53, 182,

350, 353HART, MCCOLLUM, and PULLER, 98, 340HART, MCCOLLUM, STEENBOCK, and

HUMPHREY, 357HART, MILLER, W. S.,andMcCoii/UM, 74,

107, 190, 354HART and STEENBOCK, 181, 207, 368HART, STEENBOCK, and ELLIS, N". R., 255,„ 379, 385,HART, STEENBOCK, and HOPPERT 373,

387HART, STEENBOCK, and LETCHER, 42,367,

375HART, STEENBOCK, and SMITH, D. W.,

246, 367HARTWELL, 382, 384HASTINGS, see SMITH, P.Hatmaker Process, 261HATJSMANN, 341HAUSSLER, 154, 379

INDEX 401HAWK, see SMITH, C. A.HAWK, FISHBACK, and BERGEIM, 260, 372HAWK, SMITH, C. A., and BERGEIM, 384,

385HAWK, SMITH, C. A., and HOLDER, 52,

175, 366HAWKER, see HAMSHIREHay, 192, 234, 251, 255, 330Hazel Nuts, 50, 191, 329Headache, 299, 305Heart, 57, 138, 193, 223, 328 : see also

Asthenia, cardiacHeartburn, 299, 303Heat, Effect on C, 257-262 ; see also

Boilingprolonged moderate Heating more

destructive than fierce but briefHeating, 258, 263

Heat Production and Heat loss, seeTemperature

HEFT, see EDDYHEHIR, 367HEIM, 253HEISER, 342, 344Hemeralopia, 279Hemp Seeds, 49, 59, 185, 224, 232, 329HENDERSON, see PALMERHENDERSON and PALMER, B. W., 351HEPBURN, 373HERBST, 96, 237, 238, 345, 346Herring, 193, 225

salted, 249HERRMANN, see BEGUNHERTER, 338HERXHEIMER, 85, 338HESS, 91, 236, 253, 255, 351, 353, 354,

356, 357, 362, 370, 37i, 378, 384,387; see also PAPPENHEIMER,

HESS and FISH, 349HESS and GUTMAN, 388HESS and KILLIAN, 360HESS, MCCANN, and PAPPENHEIMER, 386HESS and UNGER, 181,186, 246,251,256,

261, 360, 362,364, 367, 368, 371,374,376, 383, 387, 389

HESS, UNGER, and PAPPENHEIMER, 387,389

HESS, UNGER, and SUPPLE, 71, 382HEUBNER, 96, 352Hickory Nut, 50, 191, 329HIFT, 363HIGHET, 341HILLS, 371HINDHEDE, 41, 51, 374, 375HINKEL, see SCHOLZHINTZE, see KRUSEHIRSCH and MORO, 362HlRSCHFELDER, 309, 310, 345HlRSCHSTEINT, 96, 168, 345Histidin, 30, 31, 33, 35, 49, «5» JI7, 121HOCHST, 202HOCSON, see ARONHOESSLIN, 369HOFMEISTER, 112, 120, T24, 374HOGAN, 42, 47, 53, 55, 66, 74, "9 . x8x,_ 356, 358, 360HOLDER, see HAWKHOLST, 118, 279, 3O4, 339, 340, 342, 343,345, 36i

HOLST and FROLICH, 106, 107, 108, 244,245, 257, 253, 268, 279, 280, 339,

„ 340, 343, 347, 356, 381HOLSTI, 98, 341HOLT, 60, 374.Honey, 251, 3 31HOOGENHUYGE, See ElJKMANHOOPER, see JOHNSONHOOPER, ROBSCHEIT, and WHIPPLE, 379HOPKINS, 54,55, 75, 80,95,101,119,137,

139, *77,184,187,194, 201,229,232,236,238, 253, 317, 339, 344,348, 365,371, 382, 386; see also ACKROYD

HOPKINS and CHICK, 365HOPKINS and NEVILLE, 220, 346HOPKINS, CHICK, DRUMMOND, HARDEN,

and MELLANBY, 368HOPKINS, BOYD, WILLCOX, WALLIS,

ROAF, HUME, and DELF, 372HOPPERT, see HARTHORBACZEWSKI, 305, 308, 34IHORDEIN, 47, 176Hormones, 154, 162, 235HORNE, see GIVENSHorse Fat, 331HOWARD and INGVALDSEN, 357HOWE, 378HOWLAND and KRAMER, 389HULDSCHINSKY, 376HULSHOFF-POL, 21, 102, 107, 110, I48,

339, 340, 341, 343, 358, 377HUME, 383, 384; see also CHICK, BARNESHUME and CHICK, 101; see also CHICK

and HUMEHUME and NIRENSTEIN, 388HUMPHREY, see HARTHunger, see StarvationHunger Oedema, see Oedema, malnutri-

tionalHungerodem, see Oedema, malnutritionalHungerodem, Das, 372HUNTER, see VOEGTLIN, WATSONHUNTER, GIVENS, and LEWIS, 354HUNTER and WATSON, C.Husks, 191HUSSEY, see MACKLINHUTCHISON, 360Hyaline Degeneration, 270, 271, 288Hydantoin, 121Hydraemia, 273, 285, 288-289, 290, 291,

293Hydrarthrus, 272Hydration, 165, 167Hydrocithin, 204Hydrogen Concentration, 79, 80, 83Hydrolysis, 59, 97, 114, «o, 135, 168,

170Hydropericardium, 272Hydroperitoneum, 272Hydrothorax, 272" Hyj?iea," 243Hygiene, Nutritive, Institutes off 337Hygiene, Tropical, German Society for,

280Hyperglycaetnia, 104Hyperkeratosis, 300Hypertonicity, see ToneHypocarence, 14Hypochlorhydria, 88

402 VITAMINS

Hypoglycaeinia, 74, 273, 282Hypophysin, 202Hypophysis, see PituitaryHypotbyroidisrn, 202Hypoxantbin, 121

Iced Drinks, 216IDE, 339, 385Ill-balanced Diet, see DietImmunity, 244, 311, 312Importance of an Excess of -Alkaline

Substances, 70-75Importance of inorganic Constituents in

Metabolism, 40-41, 62-99; se* a^,°Inorganic Nutrients, InorganicSubstances

Importance of Nutrition of the Mother,204—207

Importance of Protein, 29-61, 174-179Importance of methods of preparing

Food, 183-184Inanition, see StarvationIndia, Famine Dropsy in, 279, 280Indicanuria, 300,303Infants, Feeding of, 172, ei seq., 178 255,

297; see also "breast-feedingInfection in malnutritional Oedema, 281Infection—

in Osteomalacia, 234in Pellagra, 306 et seq., 314, 317in Rickets, 237in Scurvy, 245, ei seq.intestinal, in Mehlnalirschaden, 296

Infections, Resistance to, see ResistanceInfiltration of the Tissues—

haemorrhagic, 285serous, 83, 145, 285, 287, 292, 293

etseq.Influenza, 231INGIER, 254, 350INGWALDSEN, see HOWARDInorganic Nutrients—

diet in experiments on, 332-333lack of, causing Arrest of Growth,

208their Importance in Metabolism,

40741, 62-99, 179-183, 184Inorganic Substances, their Import-

ance, 62-99, the*1 mutual inter-dependence, 90—91, 179; see also

Insomnia, 299Instinct in the Choice of Food, 191,

268Insufficiency of Vitamins (Funk's), Conse-

quences of, 126-132Interdependence of the inorganic Sub-

stances, 90-91Intestinal Flora, see FloraIntoxication by damaged Nutrients, 281Introductory, 17-28Iodine, 68Ionic Concentration, 78, 79, 83Ionic Days, 78, 79Ions, various, their Effect on the Kidneys,

290-292their Effect on serous transudation,

20.0-29.5

Iron, 274Iron as supplement to Milk Diet, 66

deficiency of, 69, 180demand for, during Growth, 180

Iron to counteract Toxicity of CottonseedMeal, 67

ISENSCHMID, 379Isolation of Vitamin, 110-116Isoleucin, 29, 33Isomerism, 49Italian Views concerning Pellagra, 307-

308Italy, Pellagra in, 307-308, 315,316, 321

JACKSON, C. M., 365JACKSON, C. M., and STEWART, 208, 364,

372JACKSON, L., 360JACKSON, F. G., and HARLEV, 339JACKSON, L., and MOODY, 356JACKSON, L., and MOORE, 356JANSEN, B. C. P., 365, 370JANSEJT, B. C. P., and MASTGKOEWINOTO,

37oJANSEN, W. H., 273, 274-, 275, 2?S, 277,

282, 36O, 372Japan und seine Gesundheitspflege, 342Japanese Experience of Beriberi, 100, 125JEPHCOTT and BACHARACH, 384JOBLING and PETERSEN, 314, 355JOHNS, see FINKSJOHNS and FINKS, 44, 48, 49, 373, 377,

384JOHNS, FINKS, and PAJUL, 50, 366, 374JOHNSON and HOOFER, 389JONGE, 340JtTR&Eisrs, 281, 354Just-Hatmaker Process, 261Kakke, see BeriberiKantara, 316Kapirin, 47KARR, 160, i6r, 381; set also LEWISKA.RRan.cL LEWIS, 246, 358Katjang:idjo, 21,106, 107, no, 135, 328Kawashina, 221, 351KELIAWAYT, 383KEMPSTER, see PALMERKENNEDY, see DUTCHER, MCCOIXUM*

PALMERKENT, see STEENBOCKKeratomalacia, 231-233KERXEY and HERMAN, 375Ketosis, SoKidney, 223, 328Kidney Fat, 225, 331Kidneys, Behaviour of, in connexion

with Oedema, 289—292KILBOTJRNX, see CHAMBERLAINKILLIAN, see HESSKIMTJRA, 368KlTTEI ON, 373KLEIMTJNGER, 347KLEINSCHMIDT, 298KLIGLER, 364KLOCKMANN, see LASTKLOTZ, 372

INDEX 403, IOI, 384

KNTACK, 276, 355 ; see also RUMPELKN-ACK and NEUMANN, 282, 358Knee-jerks, 300, 305KOCH, J., 366KOCH, M\ L., and VOEGTLIN-, 355KOCH, W., see ASCHOFFKOCHMANN, 63KOCK arid BONNE, 380KOEHLER, see ABDERHALDENKohlrabi, 392, 278, 283, 290, 330

intestinal Irritation due to, 278KOHMA>*, 1277, 282, 283, 373KONINTGER, 129, 338KORENCHEVSKY, 387KOYAMA, see YANIGAWAKRAMER, B., see HOLLANDKRAMER, 3YL M., see SHERMANKRAPT, 57, 371KRATJS, 212KRAUSE, 261KRAUT, 112Kreatinuria, 74, 199, 274, 303Kronprinz Wilhelra, 280KRUSE and HINTZE, 373KCLZ, 91, 365JKUSAMA, see SHIGA

XABBE, 372, 377Laboratory Factor, 25, 189-190Lactalbumin, 34,35, 43, 46,49,54, 56-57,

176, 177, 178, 230, 332Lactation, see Milk, Secretion ofLactic Acid, 234.Lactone, 167Lactose, 56, 186, 288, 194, 221, 245,246LAHMANN, 28, 63, 64, 65, 212LAKE, see VOEGTLIN:LANE-CLAYPON, 340LANTGSTEIN, see EDELSTEISTLANGSTEINaadEDELSTEIN, 185, 191,193,

361, 363Lard, 185, 221, 223, 225, 278, 283, 331LARNE, 344LARSON, J. H., 378LARSON, L. A., 203, 367Lavage, gastric, as Cause of Acidosis, 80LAVINDER., FRANCIS, GRIMM:, and LORENZ

306, 350Law of the Mininum, 17, 18, 25, 27, 41,

59, 68, 91, 178, 188,200, 222,241,314, 318, 326

Laxatives, 245, 246 ; see also RoughageLeaf-wax, 186LEARY and SHEIB, 359LEAVEITWORTH, see OSBORNELeaves, see Green Vegetables also SeedsLEBLANX, 378Lecithin, 97, 155, *56, 204, 295Lecithinophilia, 281Lecksucht, 7o-7rLECOQ, 58,69,138,192, 372,373LEENT, VAIT, 339LBERSUM, 385LEETJWENT, see STORM VAN LEEUWEWLEGGATE, 102, 370LEGGET, see MCCOLLUMLBGROUX, sec A&XJLKON

Legumin, 47-48, 175Legmninosae, see PulsesLEHMANST, 85, 338Lehrbuch dcr Pathologie des Staffwechsels,r 3 3 8

LEIMDORFER, see PORGESLEIPZIGER, 97, 338Lemon Cure, 77

Jiuce, 244, 249, 251, 260, 261, 330dried, 260

Lemons, 192, 224, 243, 251,252, 269, 329Lemons as cause of Acidosis, 77Leatils, 138, 244, 269LEPKOWSKY-, see HARTLettuce, 330

white, 224Leucin, 29, 33, 49Leucopenia, 304LEVA, 82, 350LEVI, 39LEVY, MAGNUS, see MAGNUS-LEVYLEWIS, M. J., see DUBIN

LEWIS, H. B., 32, 50, 57, 359, 369*377370,

L E W I S , COX, and SIMPSON, 32, 55L E W I S and KARR, 356L E W I S and ROOT, 377Lick, the 70-71L I E B E R S , 277, 373LlEBIG, 17, 25,26L I E C H T I and RITTER, 71,382L I E C H T I and TRUNINGER, 71, 346Life, Prolongation of, see ProlongationLight {see also Ultraviolet), 229Lime, see CalciumLime Jttice, 249, 251, 260

dried, 260preserved, 249

Limes, 243, 251, 329LIITD, 365LINTOSSIER, 366, 373Linseed, 224, 329Unseed Oil, 147, 185, 305, 314, 331LIMTZ, see MCCOLLUMLipochromes, 186,187, 226

in relation to A, 224-226Lipoid Solvents, 286Lipoids, 184,185, 187, 2i£, 220, 221, 22

229, 285, 294LiPSCHtfrz, 96, 341, 364L I T T L E , 107, 346, 350Liver, 57, r93, 223, 225, 252, 328

Pig's, Oil expressed from, 223L L O Y D , 138, 354LOEB, 163L O E B and N O R T H R O P , 141, 1^5, 356L O E W , see EMMERICHLOOSER, 339Lords and Ladies, see ArumLORENZ, see LAVINDER.Loss of Weight, see EmaciationLOTZSCH, see SCHEUNERTLouGHLiN, see DANIEXS, B Y F I E U >LOVELACE, 103,105,109, 346LtrcATELLO and CARLETCT, 312, 3421Lucerne, 192, 224, 252, 330L see MCARTHURL i n and BACCELXI, 311, 346L U M I E R E , 194, 375, 37&, 383

404 VITAMINS

LUNIN, 184, 338Lupines, 48, 175LUROS, see EMMETLUSK, 245LUST and KLOCKMANKT, 344LYLE, see FUNKLYMAN" and RAYMTJND, 65, 80, 369Lymphocytosis, 300, 304Lysin, 29, 31, 33, 43, 45, 46, 47, 53, 56,

176, 180, 296

MAASE and ZONDEK, 282, 372Me ARTHUR and LUCKETT, 221, 351MACALLUM, 372MCCANTN, A. W., 280, 363IMCCAN-N, G. Jt.jSee HESS, PAPPENHEIMER.IVICCARRISON-, 12, 14, 15, 104, 145, 238,

239, 273,283,292, 294, 368,371, 372,377, 378, 379, 388

MCCASKEY, see FXJNKMACLEAN, 344, 345HCCLENDON, 15, 268, 375, 380, 386HCCLENDON and BANGNESS, 388^ T C 1 , BOWERS, and SEDGWICK,

384HCLENDON and COLE, 367MCCLEN-DON, COLE, ENGSTRAND, and

MlDDLEKAUFF, 369MCCLEN-DON- and DICK, 384MCCLXJGAGE, see GIVENSMCCLXJGAGE and MENDEL, 51, 92, 362MCCOLLUM, 54, 65, 80, 98, 138,182, 183,

205, 223, 238, 340, 350, 357, 360,361, 369, 380; see also HART,MCDONALD, SHIPLEY, SOU2A

MCCOLLUM and DAVIS, 44, 53, 118, 178,i8r, 182,185, 187,190,221, 346, 350,351, 352

MCCOLLUM and HART, 44MCCOLLUM and KENNEDY, 353MCCOLLUM, LINTZ, VERMILYE, LEGGET,

and BOAS, 370MCCOLLUM and PARSONS, 73, 142, 184,

381MCCOLLUM and PITZ, 245, 359MCCOLLUM and SIMMONDS, 42,44, 47, 48,

57, 71, 91, no, ir6, 137, 188, igr,195,196, 206, 222, 232, 233, 240, 241359, 360, 362, 371

MCCOLLUM, SIMMONDS, and PARSONS, 51,175, 181, 182, 235, 246, 314, 316,3*7, 320, 360,363,364, 365, 366,385,386

MCCOLLUM, SIMMONDS, PARSONS, SHIP-LEY and PARK, 383

MCCOLLUM, SIMMONDS, and PITZ, 42, 44,46, 48, 175, 181, 182,190, 191, 192,353,354,355,356,357,358

MCCOLLUM, SIMMONDS, SHIPLEY, andPARK, 386, 387, 389

MCCOLLUM, SIMMONDS, and STEENBOCK,35?

MCDONALD and MCCOLLUM, 194,383 385,MCDOUGAL, 382MACKAY, 236, 382MCKIM, see EMMETMACKLIN and HUSSEY, 387MCLEOD, F. S., see SHERMAN

MCLEOD, J. W., and WYON, 385MCNEAL, 355, 386 ; see also SILERMACOMBER, see REYNOLDSMACY and MENDEL, 381MAGNXJS-LEVY, 276, 376Magdeburg, 250Magnesium, 180, 209, 234, 303, 3i8MAIGNON, 38, 39, 53, 55, 57, 75, 358, 362

363, 366, 367, 368, 373, 375, 377Maize, 42-44, 48, 52, 53, 54, 55, 58, 66,

73, 104, 107, 176, 177,178, 181,186,191,223, 225, 234, 244, 329

"boiled, 305Gluten, 178, 315hulled, 106, 316in Relation to Pellagra, 304-322new, more toxic than stored, 310Oil, 331

Maize Protein, Inadequacy of, 312-313Starch {see also Maizena , 327, 331, 332sterilised, 106, 119wholemeal from, 106

Maize, yellow, 223, 308-310, 317, 329Maizena, 305, 329Maladies de Carence, 10, 24Malaria, 76Malignant Tumours, 188Malnutritional Oedema, see OedemaMalt Extract, 256Malt Vinegar, 248, 252Malted Grain, 191, 329Mangelkrankheiten, 24Mangel-wurzels, 192, 224, 330MANGKOEWINOTO, see JANSENMangoes, 329MANN, 236Marasmus, see EmaciatioaMARCHOUX, IOI, 105, 376Margarine, 185, 223, 224, 232, 331MARIANI, 307 ; see also VOLPINOMARINUS, 203, 367MARKOYICI, see PORGESMARSH, see MEIGSMARTIN, see CHICKMASON, 210, 370MATHETJ, 388MATHEXJ and DAMIANOVICH, 388MATTEI, 380MATTILL, 386, 387MA TOLL and CONTKLIN, 177, 380MAXJRER, 105, 339MAYER, 284, 378MEAD, see DUTCHERMEAT, 57,61,193,196, 209, 247,269, 314,

320, 327, 328boiled, 103,106,119, 125, 160,196, 249,canned, 125, r.68, 249,252, 258, 280,

32BDiet, exclusive, 74dried, 242, 252, 334Extract, 193, 328Extract, Preparation of, 101fresh, 247, 248, 252, 269, 328frozen, 328Juice, raw, 252frozen, 107, 249over-roasted, 125pickled, 278, 283

INDEX 405MEAT {conhnt4.ed)—

Protein, compared with Milk Protein,54, 58

raw, 107salt, 107, 278, 280, 283, 328smoked, 24.2sterilised, 125,168, 170,196superheated., 106, 196tinned, see meat canneduns\nta"ble as exclusive diet for growing

animal, 196Meat eaters, clamorous, 210MEDES, see SMITHMehlnahrschaden, yy, 284, 295-297, 298

possible kunship to maWtritionalOedema, 284, 295

MEIGS and MA^RSH, 347Melancholia, 76MELLANBY, E , 186, 187, 227, 235, 236,

365, 375 ; see also HOPKINSMELLANBY, M , 361MENDEL, 39, 55, 228, 236, 352, 354*

356, 378 ; see also COHEN, COWG-ILL,MCCLTJ CAGE, MAXy, MITCHELL,OSBORNE, THOMPSON

MENDOZA-GUAZON, 356Menstruation, Effect on Metabolism, 60Mental Disorder in Pellagra, 300, 301MER, 387MXR and CAMPBELL, 382MER, CAMPBELL, and SHERMAN-, 383, 389Merck, Firm, of, 99Mesopotamia, Beriberi in, 101-102, 125,

159, 170Scurvy in, 246, 247—248

Metabolism, Importance of inorganicConstituents in Metabolism, 40—41

Metabolism in growing Organism, 179inorganic, Anomalies of, as cause of

Oedema, 287-288Metabolism, inorganic, Anomalies of, as

Cause of Pellagra, 317-318Metaphosphates, 169, 170Meteonsrn, 296, 297Methods of Preparing Food, 183-184,

277Methoxypyridin, r23Methylpyndon, 123METSCHNIKOFF, 31MEYSENBUG, 378MICHEL, zoy ; see also MOREL, MOURI-

QUAND, WEIIXMlCHELSEN, See SWEITZERMicroorganisms can synthetise A, 24.0MIDDLEKATJIFF, see MCCLENDONMIDORIKAWA, see YAMIGAWAMIGNET, see MORELMigraine, Acddosis and Lacfcof organically

combined Sulphur as contributoryCauses, 322

Milch-cows, Slaughter of, 210Milchnahrsctiaden, 77, 284, 297, 298Milk, 51, 53—57, 9O, 92, 93) 94, 133, 177,

188,192, 193, 203,209,210, 212, 220,222,225, 233, 236,237,245, 250, 251,252,253, 255, 257,268,297, 3O5, 308,315, 320, 327, 33O, 331, see alsoCasein and Lactalburnin, skim-milk,Buttermilk

Milk, condensed, 244,258, 331boiled, 250, 257, 331

Milk Diet in Sprue, 215, d seq.dilution of, in Infant Feeding, 255,297

Milk, dried, 192, 193, 197, 244, 261, 268,33i

Drying Processes, 261Milk, ESects of Heating, 20, 73,142, 183,

184, 187, 244, 258Milk Fat, 225

fat free, 221Milk, human, 330Milk, human, compared with Cow's, 35,

193Milk, human, in Benben, 162Milk, pasteurised, 197,258,261, 262, 297,

33iMilk Protein, 48, 53-57, 58, 176, 177,

178, 184Milk Protein, as only Protein for Adults,

177 , s^ako Casein and LactalbuminMilk, protein free, 56, 64,88, 90, 140,141,

177,186, 193, 256Richness in Calcium, 180

Milk, Secretion of, 50, 175, 253-255Effect of Diet upon, 206,240, 241

Milk, stable in quality under -varying con-ditions of maternal nutation, 57, 71

sterilisation, of, see Milk, heatingtinned, see Milk, condensed

MILLER, E M, see PHEMISTERMILLER, E W, 141, 381, 388MILLER, W S , see HARTMillet, 47, 185, 224, 232, 329Minimum, Law of the, see LawMITCHELL,H.H, 3435, 36, 142,355,3&9MITCHELL, H S , and MENDEL, 389Mttieilungen der Beriberikommission, 342MIURA, see ZILVAMixed organic Compounds, 96, 155,169,

170MOCKERIDGE, 356, 376MOGI, see YAMIGAWA.MOLTRAM, see CRAMERMONACO, 354Monotonous Diet, see DietMOODY, see JACKSON, LMOORE, B, see EDIEMOORE, J J , 361; see also JACKSONMtooRE and JACKSON, 356MOREL, MOURIQUAND, MICHEL, and

THSVON, 389MOREL, MOURIQUAND, and MIGTJET, 383MORESCHI, 339MORGEN and BEGER, 352MORGULIS, 387MORI, 339, 342MORO, see HiRScaMORSE, 348Moss, Insh, 236MOSZKOWSKI, 107, 343MOURIQUAND, see MOREL, WKILLMOURIQUAND and MICHEL, 246,371, 377>

383, 389MUCKENFUSS, 364Mucor racamosus, 308Mulberries, 329MCLLER, 14, 84, 212, 25O,26l,M and BRANDT, 373

406 VITAMINS

MttNZER, see BEGUNMURATA, 383Murmansk, Scurvy in, 24.8, 249Muscarin, 143, 144Muscle ; see also MeatMuscle, fresh, contains Abundance of

Funk's Vitamins, 124Muscles, Condition in Beriberi and Ex-

perimental Polyneuritis, 157, et seqMuscles, Effects of Vitamin on, 144Muscular System, Energetics of, 146-148Mush, 29 6Mutton Fat, 331Mutual Interdependence of the Inorganic

Substances, 90-91MYERS, see CHASE, VOEGTLIN-MYERS and FINE, 347MYERS and VOEGTLIN, 53, 115, H7>

3.70, 375Myositis, 128Nahrungsntitteltheorien Uber die TJ-rsache

det Beriberi in kritischer Beleuchtung,343

Nahrungs und Genussmittel, 347KAKAMURA., see ONODERANashville, Pellagra in, 314NASSAU, 374Nausea, 279Need for State Aid in Experiments on

Nutrition, 337NEHRING, see SETTLERNEILL, see VOEGTLINNELSON, see FULMER, SXEENBOCKNELSON and LAMB, 232, 375NELSON, FULMER, and CESSNA, 384Nephritis, 81,300NEPPI, 380NEUMANN, 276 ; see also KNACKNeuralgia, 299, 300Neurasthenia, 126, 281, 305, 315, 322Neurin, 121Neuritis, 283 ; sec also Beriberi, Poly-

neuritisNEVILLE, see HOPKINSNewer Knowledge of NutritionNICHOLLS, L., 346, 364NICHOLLS, N. B., see DANIELSNICOLAIDI, 346, 347Nicotinic Acid, ir2, ri3, 121, 122, 123Nicotinic-Acid-Nicotine-Ester, 122NIELSEN, see SCHMIDT-NIELSENNlGHriNTGALE, 316, 349NIRENSTEIN, see HUMENISTICO, 302, 344Nitrogen Hunger, 275Nitrogen, residual, 273Nitrogen Retention, 8r, 82, 294,313Nitrogenous Balance, 75, 81, 82,103,130,

275, 303, 314; see also NitrogenRetention

Nitrogen-free Diet, Effects of, 36Nitrogenous Balance (see also Nitrogen

Retention), 267, 270, 30aNitrogenous Fertilisers, Excess of, pro-

duces acid Fodder, 71Nitrogenous Residues, Retention of, see

Residues, also Nitrogen Retention

NITZESCU, 32, 43. 81, 310, 311, 313, 349,350, 352, 364

NIXON, 275, 277, 282, 379NOBEL, 257, 382, 386 ; see also FORTHNOCHT, 129, 279, 280, 281, 339, 340, 358NOLLATJ, see BUCKNERNomenclature, 21-24NOORDEN, 85, 338Norleucin, 33NORTHROP, 208, 358, 359 ; see ulso LOEBNosebleed, 242, 266NOVARO, 372, 374, 375NOVELLA, see ALPAGO-NOVELLA, VOLPINONuclein, 123Nucleinic Acid, 121, 156Nucleoproteins, 97, 156, 169, 171Number of Experiments, inadequate, 325Nut Oil, 224, 331Nutramin, 22, 147, 195Nutrition in Complettin Experiments,

327, 332-336Nutritive Pills, 31Nutritive Salts, see Salts

Yeast, see YeastNuts, 50, 232, 329 ; see also under specific

names, as Walnuts, Almonds, etc,Nycturia, 273, 290Oatmeal, 185Oats,46,51, 54,55,58,176,181, 191,223,

244, 247, 249, 253, 329Observation, Period of, sec Duration of

ExperimentsOccurrence of the Vitamins (Funk's),

124—126ODAKE, see TSUZUKIOedema, 90, 108, 145, 160, 269

cardiac, 272, 274causes of, 284-293dyscrasic, 285in Beriberi, 130, i3r, 132, 271, 272

Oedema, in Mehlnanrschaden, 296, 297,in Scurvy, 267malnutritional, 109, 126,133, 238—239,

271-298 (for Details see Table ofContents, Chapter Eight)

Oedema—passive, 27r, 272renal, 271, ay2

Oedematogenic Diet, 285, 286, 290Offspring affected by parental Diet, see

Dietetic ErrorsOHLER, 349Oils, 331; see also under specific Oils, as

Codliver Oil, Olive Oil, etc.mineral, as Laxatives, 246

Olein, 185, 223, 33rOleomargarine, 185, 223, 331Olive Oil, 185, 224,236,331OLSKN-, 370Onions, 249, 252, 330

boiled, 249raw, 248,252

ONODERA, NAKAMURA, and TATENO, 345Orange Juice, 139, 186, 187, 192, 197,

251, 252, 253, 260, 261, 329,dried, 200Peel, api-peel oil, 331

I N D E X 407Oranges, 192,224, 251, 252, 329ORGLE-R, 342, 343Oridia, 22,112, 120ORMEA, 339Omithin, 29, 31Orthophosphates, 169, 170Orypan, 22, 143Oryzanin, 22, 112OSBORNE, 16, 65, 69, 88, 160, 173, 184,

186,313,327,333,357,3^OSBORNE and LEAVENWORTH, 384OSBORNE and IVLENDEL, 31, 32,41,42, 43,

, 44, 45, 46, 47, 48, 49, 52, 53, 55, 56,57, 58,63,64, 65, 69, 91,96,107,119,140,177,178,184., 188,190,191,192,193,194, 205, 207,208, 220, 221,224,226,228, 235,253, 256, 313, 334, 335,342,344,34-5, 348, 349, 352,353,355,357, 358, 360, 362, 364, 373, 3S2,383,3S4, 385

OSBORNE, MENDEL, and FERRY-, 31, 344,365

OSBORNE, MENDEL, FERRY, and WAKE-MAN, 99, 347, 35r, 358, 359, 36r, 366,367, 368

OSBORNE, MENDEL and WAKEMAN, 181,190, 374, 375, 380

OSBORNE and WAKE MAN, 114, 117, 118,35i, 356, 369

OSBORNE, WAKEMAJT, and FERRY, 368Osmosis, 287, 288, 289Osmotic Pressure, see PressureOsteomalacia, 58,72,86,227,233-235,239Osteopathy, 234, 239, 265, 266, 267, 269,

270 (see also specific Bone Diseases,as Osteomalacia, Rickets)

Osteoporosis, 58, 70, 86, 254OTTO, 307, 339O U T H O U S E , see D A V I S , M.Ovalbumia (sometinies called "Egg Albu-

min, to be distinguished from t h eVitellin of the Yolk), 43 , 53, I7&

Ovaries, 193Overheating of Food, see Sterilisation

and Sterilised F o o dO W E N , 379Oxidation of A, 229, 334

C, 257,261, 262, 263, 334Oxidation of Acid-formers, i ts Effect on

their •biological Value, 94-99Oxynicotinic Acid, 122, 123Oxyprolin, 30, 35Oxypyridin, 123Ozone, 229

P A C I N I and R U S S E L , 193, 360PADUA, 369Palm Oil, 331PALMER, B . W. , see H E N D E R S O NPALMER, B . W., and H E N D E R S O N , 81,351,

369PALMER, L. S., 352, 355, 368PALMER, L. S., and E C C L E S , 348PALMER, L. S., a n d KEMPSTER., 187PALMER, L. S., K E N N E D Y , and KEMPSTER,

385Palmin, 185Pancreas, 138, 193, 239

Pap, 183PAFPENHEIMBR, see H E S S , SHERMANPAFPENHEIMER, MCCANN, ZUCKER, and

H E S S , 386PAFPENHEIMER and MINOR, 385Para Nuts, 50, 191, 329Paradoxical Effect of Calcium Salts in

t h e Organism, 83-87Paraesthesia, 279, 284., 299, 300Paralysis [see also Paresis), 300 ; see also

Polyneuritis, and Beriberi, passimParaplegia spastic, 300Parasitism, 240, 241Parasympath.etic, 14.3Parathyroid Extract , 122Paxaxanthin, 121Parents ' Diet affecting Offspring {see

Dietetic Errors)Paresis (see also Paralysis), 300, 316;

see also Polyneuritis, and Beriberi,passim

PARK, see MCCOIXTJM, SHIPLEY"PARK and HOWLAND, 389Parsnips, 224, 330PARSONS, 381 ; see also MCCOLLUM,

SHIPLEY-PASCH, 388Pasteurisation, see MilkPATON-, 98, 338 ; see also F I N D I A YPATON-,FINDXAY, and WATSON, A. H.,363P A T O N and WATSON, A. H., 383P 7, 3 7 , 3 4PAUL, see J O H N SPea Flour, boiled, 305, 314Pea Legurnin, 47-48Pears, 191, 209, 329Peas, 4S-49, 175, 244, 249, 269, 280, 328

germinated, 248, 328green, 106young green, 290, 328,

PECKHAM, 74, 382Pellagra,, 34.8Pellagra, 42, 238, 299-322 (for Details

see Table of Contents, Chapter Nine)Pellagra and Beriberi, 316, 319

and malmitritional Oedemaand Scurvy, 319

Pellagra sine Pellagra, 300, 321Pellagra Commission Reports (U.S.), 34-9,

351, 357,Pellagrogenic Factors, 304-322Pellagrogenin, 308, 311PENAU and SIMMONTET, 387Penicilliuin, 308Peoicillium glaucum, 307Pericarp [set also Silverskin), 102, 105,

140 ; see also BranPeriod of Observation, see Duration of

ExperimentsPeristalsis, 199P E R L Z W E I S , 351PfeRONNET, see WEXLLPETERSON, see TALBOTPETTENKOFER, 26PETTERSSON, see E U L E RP E Z A R D , 57, 370Phaseolin, 48, 59, 175Paaseolus radiatus, 21, 107; see also

Katjang-idjo

40 8 VITAMINS

PHEMISTER, MILLER, E. M., and BONAR,384

Phenolphthalein, 246Phenyl-alanin, 29, 31, 34PHILLIPS, see SHERMAN-PHLORIDZINT, 122Phosphatases, 156Phosphates, Deficiency of, 15 5

Deficiency of, as Caiise of Pellagra, 317Excess of, 295

Phosphates, organic, 169, 170, 171Phosphatic Metabolism, 84-87,91, 96-99,

156, 180Phosphorus, 179, 234, 235, 274Phosphorus Balance, 81, 102, 103, 156,

267,275,303,318Phosphorus Compounds in Food, 95

{see also Phosphatic Metalbolism)Phosphorus—

organic Compounds of, 155organic Compounds cannot be reduced

by Anirnal Organism, 97Photodynamism, 313Photophobia, 300Phytin, 155, 156Pica, 70-71PIERSON, see DUTCHERPIERSON and DUTCHER, 371Pig Fat, 331Pike, 138Pilocarpin, 122, 143, 144Pine Kernels, 50, 191, 329Pituitary Body, 143, H4, *45, *93> 201,

202, 203, 273Pirz, 245, 253, 360, 363 ; see also

MCCOIXUMPlankton, 98PLANT, 199, 381Plants, vegetative (green) portions vs.

storage portions (roots and tubers)as Sources of Funk's Vitamins, 124as Sources of C, 252

Plasmon, 336PJLUMMER, R. H. A., 9, 12, 257, 376PLIMMER, VIOLET, 9, 12Plums, 191, 329POKXOP, see FUNKPOL, see HULSHOFF-POLPOLLINI, see PRETIPolyneuritis [see also Beriberi), 77, 101-

171, 292, 305Etiology, 100-109Experimental, of Birds, 174Gallinarurn, 106

Polyuria, 273, 290, 291POOLE, see RIVERSPOPIELSKI, 203, 382PORCHER, 374PORGES, LEIMDORFER, and MARKOVICI,

79, 342, 347Pork, salt, 249Porridge, 296PORTER, 377PORTIER, 143, 153, 154, 365, 374; see

also BIERRYPORTIER and RANDOIN, 163,197, 368, 372Potassium, 209, 233, 296, 298, 318, 322

Balance, 102, 303Ions and Oedema, 294,295; see also Ions

Potassium Salts, stimulating Influenceof, 82, 290, 293-295

"urinary Excretion and, 290Potato Protein, 175, 176Potato Starch, 160, 332, 333Potato Water as Source of Nutritive

Salts, 90Potato-control, 210Potatoes, 51, 58, 66, 124, 182, 186, 192,

209, 215,217,224, 227, 232, 244, 248,249, 257, 278, 280, 283, 318, 330

baked, 259boiled, 124,196,249, 252, 257, 258, 259,

330dried, 197, 244, 258, 259, 260, 280, 330raw, 248, 252, 258, 330sweet, 192, 224, 330 A „_

POVITSKV, see WILLIAMS, A.. W.POWERS, see SHIPLEYPrecipitin, 308, 311, 3*2

Preserved Foods and Scurvy, 243Pressure, osmotic, 89, 288, 289, 291, 293,

294PRETI and POLLINI, 342, 344Prison Dropsy, 279, 280

identical with malnutritional Oedema,280

PRITCHARD, 368Problems of Complettin Research, imme-

diate, 336Procreation, Capacity for, affected by

Errors in Diet, 72, 173, *74Proletarische Kind, Das, r 4Prolin, 30, 31, 33,49Prolongation of Life, 208Properties of Funk's Vitamins, 116-124Proteid vs. non-proteid Substances as

Nutrients, 37—40Protein Diet, an exclusive, is toxic, 38,

in relation to Acidosis, 76Importance of, 29-61, 172, i74-*79

Protein Insufficiency and Inadequacycausing Arrest of Growth, 208, 321general Results of, 321in Relation to Malnutritional Oedema,

277,282in Relation to Pellagra, 315-318, 320,

321Protein Insufficiency and Inadequacy in

Relation to Scurvy, 246minimal daily Requirement, 61

Protein Requirements -vary at differentAges, 60

Protein-calorie Doctrine, 326Protein-free Milk, see MilkProteins, biological Value of, 29-61

conditions requisite for Efficiency ofvarious kinds, 56-61

Proteins, inadequate, several, can com-pensate one another's deficiencies,244

Proteins, only a moderate amountrequisite, 40

over-estimation of their importance indiet, 172, 174, 175, 178

Proteins, specific, see under source (asMaize, Rice, etc.), and underspecific names (as Zein, Casein, etc.)

INDEX 409Psilosis, see SpruePsoriasis, 76Psychical Influences in Experiments on

Nutrition, 325Psychosis, War, 281Public must be enlightened regarding the

neyv Science of Dietetics, 337Pulse, infrequent, see BradycardiaPumpkin Seeds, 49, 50, 176

Sauash, 330Pulses, 48-4.9,182,186,191, 223, 269,315,

320, 328proteins of, 175 ; see also under specific

names, as Haricot Beans, FodderPea, Katjang-idjo, etc.

Purin, r2iPurpura, 265, 266, 269

kaemorrhagica, 269simplex, 269

PTOTTER, 98, 340PurziG, 377Pylorus, Stricture of, 80Pyrexia, 266; see also TemperaturePyrimidin, 122Pyrophosphates, 169, 170

QUITTNER, see FALTA

Rachitis, see RicketsRadishes, 330Radium, 120, 142, 198, 353RAIMONO, 146, 350, 351RAMSDEN, 228, 230, 361RANTDOIN-F.AISRDARJ>,$££ BLEHRY, PORTIERRape-seed Oil, 185Raspberries, 329Ratios of nutritive Substances in Diet,

37-4ORAUBITSCHEK, 309, 312, 313, 342, 346,

•O 353 T>RA\T, see ROBERTSONRAVMUND, sec LYMANTREAD, see SUREREED, 376Recherches swy le rdle des %raisses dans

Vutilis&Hon, des cdburnoides, 368REICHE, 298, 375Relationship of proteid to non-proteid

nutritive Substances, 37-40RENSHAW, 383Report on the present State of Knowledge

concerning accessory Food Factors, 10Reserve Alkalinity, 79, 80Residues, Retention of, 44, 45, 82; see

also Nitrogen RetentionResistance to infective Agents, 199, 230,

231, 239, 267, 317Respiration, internal, 144, 145, 146, 147,

158Respiratory Quotient, 104, 146Retention of Nitrogen, etc., see Nitrogen,

etc.Retinitis, 300REVNOLDS and MACOMBER, 387Rhagades, 300RHODES, see CHICKRhubarb, 330

Rice, 41-42,100, 139, 159,176,178, 181,186, 216, 249

Bran, in , 113, 118,133, 134,135, 137,139, 156

damaged, 105hulled, r06, 107, 125Halls, 121Husks, 112polished, ior, 102, 104, 105, ro6, 107,

ii2f 125, 132,135,136,137,139, 155,159, 171, 192,196,305

polishings, no, nr, 143 (see alsoSilyerskin)

sterilised, 119unhulled, 106, 119, 141, 155Vitamin, 122

RICH, 379RICHARDSON and GREEN-, 50, 55, 178,

182, 354, 358, 359RlCHET, 366RlCHTER, 346Rickets, 233, 234, 235-238,239, 242, 250,

254, 265, 284RlESELL, 85, 338Ring Compounds, Deficiency of, 176Ring-closing, see CyclopoiesisRipening diminishes C Richness of

Frui t s and Vegetables, 251, 255RIOTER, see L I E C H T IR I V E R S , 386R I V E R S and P O O L E , 387R O A F , 302, 377R O B B , 378R O B E R T S , 307, 320, 370ROBERTSON, 355ROBERTSON a n d CUTLER, 355ROBERTSON a n d DELPRAT, 359ROBERTSON a n d R A Y , 60, 145, 190, 195,

202, 203, 204,325,326, 353, 365, 366,375, 381

ROBISON, 365 ; see also HA.RDENRobots , 15ROBSCHEIT , see HOOPERRodents, specially susceptible to Acidosis,

108susceptibility to Scurvy, 268

ROGOZINSKI, 99, 341R 6 H M A N N , 2 2 , 2 3 , 6 3 , 6 9 , I I Q , 2 3 5 , * 4 6 ,

313, 339, 353, 354 •R O I X Y , 345Romberg's Symptom, 300ROMMEL and V E D D E R , 107, 352JRONDONI, 309, 310, 312, 342, 345> 348,^ 365ROOT, see L E W I SRoot Crops, see Roots and TubersRoots and Tubers , 182,186, 224, 225, 252,

330R O P E R , see E d d yR O S E , 92 ,93 , 94, 3 /1 , 373> 389, o £R O S E , 18, 58, 6 r , 62, 71, 72, 75, 84, 86,

205, 206, 276,291, 339, 343, 35i , 358R O S E and B E R G , 363R O S E N A U , 389R O S E N BAUM, 381ROSENBERG, see SALLERROSEKHEIM, 356R O S E N H E I M and DRXJMMOND, 225, 226,

375

4io VITAMINSRossi, 362ROTH, see BENEDICTROTHSTEIN-, 83, 276, 364, 371Roughage, 160, 190, 327, 333ROUSE, see SHERMANROY, see SHORTENRUBNER, 17, 19, 26, 51RUHL, 316, 352RttHLE, 14Rumania, Pellagra in, 304Rummelsburg Orphanage, 250, 261RUMPEL, 354.RUMPEL and KNACK, 279, 352, 356RUSSEL, see PACINIRussia, Scurvy in, 248, 249RUTHERFORD, 383Rye, 45-46, 47, 59, x75i *76, 223

Salad, 248, 252, 269Salads, see VinegarSALEEBY, 364 ; see also WILLIAMS, R. R.Salivary Secretion in Scurvy, 267Salivation, 299SALLE and ROSENBERG, 370Salmon, preserved, 193Salmon, Spawning of, 98Salonica Front, Scurvy at, 249Salt Mixtures—

Aron's, 6Sy 336McCoUum's, 65,183Osbome's, 65-66, 180, 183, 327, 333Osbome and Mendel's, 64, 65Rohmann's, 63, 64.

Salt, Table, see Sodium ChlorideSalts (see also Alkalies and Bases), 40-41,

43, 5i, 57, 241Buffer, 79, 81Deficiency of, 233, 250, 268Deficiency of in maternal Diet, 207

Salts, inorganic, in Maize, 43in Milk, 206in Relation to Scurvy, 268in Relation to Sprue, 217in Relation to urinary Excretion, 290-

292Salts, nutritive, 17,18, 181

natural, 90supply of a Sufficiency of, 62-67,

184Salts, Retention of, 294SAMELSON, M., 105, 379SAMELSON, S., see ARONSand as Roughage, 190SANTOS, 387SAUERKRAUT, 330SAWAZAKI, 105, 346SAWYER, BAUMANN, and STEVENS, 359SCALA, 69, 382; see also ALESSAUDRINIScalding of Vegetables, 210, 211SCHABAD, 340SCHAEFER, See DUTCHERSCHAEFFER, 364SCHAMELHOUT, 377SCHATTKE, See SCHEUNTERTSCHAUMANN, 19, IO3, I06, IO7, 113, Ir7>

118,120, 121, 129,133,134,135, 136,143, 155, 156, 157, 170,280, 339, 340,341, 342, 343, 344, 345, 347, 349

SCHEARER, 356SCHETELIG, 85, 338SCHETTLER, See SOLLMANSCHEUNERT, 234, 373SCHEUNERT, SCHATTKE,and L6TZSCH, 334S C H I F F , 343, see CRAMERSCHIPFMANN", see A B D E R H A L D E NSchilde Company, see Benno-SchildeSCHITTENHELM and SCHLECHJT, -273, 275 ,

276, 277, 284, 367SCHLECHT, See SCHITTENTHELMSCHLESINGER, 283, 371, 376SCHLOSS, 96, 237, 238, 340, 341, 342, 344»

346, 348, 349, 353, 356 ; see alsoF R A N K

SCHLOSS and FRANK, 348SCHMIDT, see ABDERHALDENS C H M I D T - N I E L S E N , 243,339SCHMORL, 350SCHN\TDER, 3 4 9SCHOLZ and H I N K E L , 83, 349SCHONTBORN, St& FUNKSCHUBERT, 339SCHULZ, see F O R B E SSCHWARTZ, 376SCHWARZ, see F R A N K E LSCHWEIZER, 384, 388Science of Eating, 363Sclerotinia cinerea, 240Scorbutogenics, 244, 249, 251:, 254, 255 ,

256, 258, 267, 268, 269Scofbutus, see ScurvySCOTT, see Eustis, W E L L M A NScurvy, Past and Present, 370Scurvy, 106, 108,109, 126, 133, 211, 218 ,

236, 242-270 (for Detai ls see T a b l eof Contents, Chapter Seven), 2 7 2 , 2 7 8279, 280, 283, 299

infantile, 254, 255, 258, 265, 269, 2 9 7Sea Voyages and Scurvy, 243Seal Meat, fresh, as ant iscorbutic i n

Polar Exploration, 252SEAMAN, 379Se"borrhoic Dermatit is , 76Secretion, 144Sedgwick, see MCCLENDONSeed Protein, 178, 180Seeds, 185,191, 223, 252, 253, 255, 256Seeds deficient in inorganic N u t r i e n t s ,

182,183Seeds, see Cereals, also u n d e r specific

names, as Cotton Seeds, H e m p Seeds ,etc.

Seeds and Leaves contrasted as r egaxdsinorganic contents, 70 et seq.

as regards A content, 22 4preparat ion of, as Food, 107

Seeds are rich i n Funk ' s Vi tamins , 124SEGAWA, 102, 134, 347, 349S E I D E L L , 113, 355, 357, 383, 386, 387 ;

see also WILLIAMS, R. R.S E O W E , 373SELL, see STEENBOCKSerin, 29, 31Serological Constants, 231, 267

Relations in Pellagra, 312Serum as Remedy for P u r p u r a , 269Serum Albumin, 164

Pressure, 285

INDEX 411SHA»RPE, see FIND LA. YSHA.W, 76, 80, 374, 377SHEIB, see LEARYSHERMAN, 42, 54, 61, 326, 370, 372, 386;

see also MER.SHERMAN, MCLEOD, F. S., and KRAMER,

37iSHERMAN, MER, and CAMPBELL, 383, 387SHERMAN and SMITH, L. H., 14, 326, 389SHERMAN and PAPPENHEIMERJ 385, 388SHERMAN, ROUSE, ALLEN, and WOODS,

385SHERMAN, WHEELER, and YATES, 42,

4-4, 361SHERMAN and WINTERS, 42, 44, 362SHERMAN, WINTERS, and PHILLIPS, 46,

368SHERWOOD, sec FULNERSHIBAYAMA, 341, 345SHIGA and KTJSAMA, 342SHIMAMURA, see TOUZUKIShip Berberi, see BeriberiSHIPLEY, zee MCCOLLUMSHIPLEY, MCCOLLUM, and SIMMONDS,

389SHIPLEY PARK, MCCOIXUM, SIMMONDS,

and PARK, 383, 386SHIPLEY, PARK, POWERS, MXCOLLUM,

and SIMMONDS, 388SHORTEN and ROY, 385SILER, GARRISON, and MCNEAL, 306, 314,

348, 349,351,354,357Silicates in Pellagra, 318Silicates, soluble, are they essential?

68 et seq.Silicic Acid in Pellagra, 318-319SiTverskin {see also Pericarp, also Rice

Polishings), 102, no', 111SIMMONDS, see MCCOLLUM, SHIPLEYSIMON, 368SIMONNET, 159, 160, 161, 333, 381 ; see

also PENAXJSimpler Natural Bases, The, 349SIMPSON, G. E., see EDIE, LEWISSIMPSON, G. E., and EDIE, 342SIMPSON, K, 104, 376SIMPSON, S., 203, 377Sitacoid, 22SKELTON, see CHICK, DEL*Skim-milk, 186, 193,222, 232, 233, 33*Skin, 200SLATOR, 363Skorbut, Der, 368Sleeplessness, see InsomniaSLYKE, see WHIPPLESLYXE, CULLEN, and STILLMAN, 79> 80,

35i, 352SMITH, A. HE., 363, 365SMITH, C A., see HAWKSMITH, C. A., BERGEIM, and HAWK, 388SMITH, D. W., see HARTSMITH, E., and MEDES, 388SMITH, F., and HASTINGS, 109, 346SMITH, H., 281, 353SMITH, L. H., see SHERMANSMITH, ~L. ML, and LEWIS, 359SMITH, P. W\, see BASSET-SMITHSMITH, X, 338Smoking, see Tobacco

Sodium, 233, 241Bicarbonate in Treatment of Scurvy,

269Chloride, 274, 287-288

Sodium Chloride, Craving for, 276excessive use as Seasoning, 290, 294,

.321Sodium Chloride, Excretion of, 276, 291

Metabolism, 275-276, 287Retention of, 276

Sodium Chloride, storage of, 81, 82Sodium, Deficiency of, in Cereals, 296

in diluted Milk, 298Sodium Ions and Oedema, 287-288, 293-

295Sodium Salts, paralysing Influence of, 82,

275, 276,287-288, 293-295urinary Excretion and, 290-292

SOLLMANN, SCHETTLER, and WETZEL, 381Soup, 250

Powders, 278Tablets, 278

Sourness of Soil, effect on Plants asNutrients, 71

South Carolina, Pellagra in, 307SOUZA and MCCOLLUM, 380Soxhlet Apparatus, 184Soy Beans, 49, 59, 66, 118, 119,176,186,

191,192,223, 253,328Spartanburg, Pellagra in, 307Spasm, tonic and clonic in Pellagra, 300Spasmodic ASections, 76, 160, 235 ; see

also under specific Names, as Carpo-pedal Spasms, Epilepsy, etc.

Spasmophilia, 284, 294, 295Spastic Paraplegia, 300SPIIVLMAN, see BRTJNTZSpinach, 5r, 92, 192, 200, 209, 217, 224,

225, 251, 252, 330, 332, 335boiled, 249, 330dried, 330raw, 211, 330

Spleen, 328SPRAWSON, roo, 101, 378Sprue, 212—218

clinical Picture, 212-213Etiology, 215-218pathological Anatomy, 213—214Prognosis, 214Treatment, 215

Stall-feeding, 194STAMPERS, 382, 387Standard Diets for Experimental Work,

327, 332-336STANLEY, see TROWBRIDGESTANTON, A. T., see FRASERSTANTON, E. E., see SULLIVAN1

Starch, 221, 277, 33*, 335{see also special Starches, as Potato

Starch, etc.)STARK, 355Starvation, r59, 161, 162, i6<3, 282 309Starvation States, 171Starvation States and Polyneuritis, 148-153State Aid needed in Experiments on

Nutrition, 337Steaming of Vegeta"bles, 210, 211 ; see

also Bleaching .

412 V I T A M I N S

Stearin, 185, 223, 331STEENBOCK, 357, 360, 362, 367 ; see also

ELLIS, N. R., HARTSTEENBOCK, BOTJTWELL, GROSS, and SELL,

223, 228, 371STEENBOCK, BOTJTWELL, and KENT, 225,

229, 362STEENBOCK, BOTJTWELL, SELL, and GROSS,

372, 375STEENBOCK, GROSS, and SELL, 192, 224,

369, 372STEENBOCK and HART, 346STEENBOCK, KENT and GROSS, 47, 362STEENBOCK, NELSON and HART, 74, 80

35O, 388STEENBOCK, SELL, and BUELL, 385STEENBOCK, SELL, and BOUTWELL, 386STEFANSSON, 361, 364STEINACH, 28STEINITZ, 97, 338STEPHENSON, 382STEPHENSON and CLARK, A. B., 379STEPP, 138, 184, 219, 220, 221, 226, 227,

229, 231, 340, 342, 345, 347, 35O,354, 366

Sterilisation, destroys Vitamins, 101Sterilised (superheated) Food, 197

(see also under specific foodstuffs, asMeat, Milk, etc.)

Sterilisation, Effect on Vitamin, 119,etseq., 125

of Meat, see Meatof Milk, see Milk

Sterilised Food ia Dietetic Experiments,189, 198

Sterins, 226STERN, 379STERNBERG 349, 350STEVEN'S, see SAWYER.STEVEN-SON-, A. G., 380STEVEN-SON, H. C, see EDDYSTEWART, 201,361, 371 ; see also JACKSONSTILL, 236 ; see also HARDEN, 2ILVASTILLMAN, see SLYKEStock-fish, 193STOCKHOLM, see EMMETStomach, Lavage of, as Cause of Acidosis,

80Stomatitis, 266Storage, Effect on C content of anti-

scorbutics, 253, 257, 261, 262Storage Fat, 185, 223

Tissues, 192STORM VAN LEEUWEN and VERZAR, 385Strangury, 291STRAUSS, 85, 338Straw, 251Strawberries, 215STRONG and CROWELL, 105,135,344Strychnine, 121Studies in Deficiency Disease, 12SUAREZ, 304, 309, 353Suet, 236, 331Sugar, 186, 236, 246, 24.9, 268,296, 331Sugar Beet, see BeetSUGTURA, 114, 137SUGIURA and BENEDICT, 50, 140, 142,

191,198,363,369SULLIVAN, 373 ; sec also VOEGTLIN

SULLIVAN and JONES, 373SULLIVAN and VOEGTLIN, 353,SULLIVAN and STANTON, 378SULLIVAN and DAWSON, 384SULLIVAN, STANTON, and DAWSON 386Sulphates, excess of, 295Sulphur, 56, 95, 96, 179, 269, 303

Balance, 81Lack of, 269Neutral, of Urine, 95Organically combined 333Organically combined, Deficiency of,

296, 303, 322Sulphuretted Hydrogen, 168Sulphhydril Group, 168Sunflower Seeds, 59Superheating (120° C.) for three Hours

destroys all Antiscorbutics, 258SUFPLEE, see HESSSupply of a Sufficiency of Nutritive

Salts, 62-67Suprarenal, see AdrenalSURE, 33, 56, 32% 380SURE and READ, 382SUZUKI, seeTsvzyKtSweden, Scurvy in, 242, 250, 251Swedes, 192, 330Sweetness of varieties of Citrus, their

richness in C proportional to, 251Sweetstuffs, 327SWEITZER and MICHELSON, 76, 374SWOBODA, 381SYDENSTRICKER, 352; see also GOLD-

BERGERSynthetic Powers of Animal Organism,

165 et seq., 253Syrup, 236

Tahle Salt, see Sodium ChlorideTAKAKI, 338, 339TALBOT, DODD, and PETERSON, 346Tamarinds, 330TANJI, 146, 362TANNER and ECHOLS, 386Tares h6re"ditaires, 15TASAWA, 103, 348TATENO, see 0 NOD ERATea, 2r6, 249Teeth, carious, 209, 248, 265Teeth, loosened in Scurvy, 266TELFER, 383Temperature, Body, 146, 148^53, 154*

273, 308, 3ro ; see also PyrexiaTennessee, Pellagra in, 314TERAUCHI, 341TEREG, 96TEREG and ARNOLD, 338Terminology, see NomenclatureTERREIN, 173, 378TERROINE, 39, 366Test, Dietetic, 173Testicles, 193Tetany, 80, 235, 296 ; see also Carpo-

pedal SpasmsTethelin, 145, 202, 203Tetraoxypyridin, r23THEVON, see MORELTHJOTTA, 386

I N D E X 413THJOTTA and AVERY, 388, 389THOLIN, 388THOMAS, 51 ; see also RUBNERTHOMPSON1 and MENDIL, 208, 361Thymin, 121Thymo-nucleinic Acid, 121Thymus, 193, 223Thyroid, 193, 273Thyroid Extract, 122Thyroidectomy, 203Timothy Grass, 192, 224, 252, 330TIRABOSCHI, 307, 340Tissue Builders (see also Amino-acids),

18, 47, 164, 208TIZZONI, 307, 342, 343Tobacco, 216TOBLER, 364Tomatoes, 192, 196, 224, 251, 329

dried, 260Tone, arterial, 294

muscular, 284, 294, 296, 301nervous, 2 95tissue, 297, 298

Tonsillar Hypertrophy, 209Tonilin, 22TOTANI, 58, 357TOWLES, see VOEGTLIWTown-dwellers, Scurvy among, 242, 243Toxaenaia, 245, 272Toxins in Maize, 307 d seq.TOZER, 383, 386Tremor, 300Trichoderma lignorum, 308Trigonellin, 122, 123Tricxypyridin, 123Tropical Hygiene, German Society for,

280TROWBRIDGE, see FRANCISTROWBRIDGE and STANLEY, 170, 341TRTJtf INGER, See. LlECHTITryptophan, 30, 31, 32, 34, 43> 45, 46, 47,

49»53,54,56, X031 176TSCHIRSCH, 37OTSIRSCH, I56TSXJZXJKI, 340, 348TSUZXJKI and SHIMAMXJRA, HI , 341TSTJZTJKI, SHIMAMURA, and ODAKE, 112,

118, 344Tubers, see RootsTULLIS, see ALBERTOUITumours, 188, 193, 201, 216Turkish Prisoners, Pellagra among, 316,

320Turnip Juice, 260Turnips, 192,197, 224, 227, 252, 330

"boiled, 258Turnover, basic, 60, 73Turnover, increased, in growing Or-

ganism, 179Twitching, 300Typhoid Bacilli and Growth-factor, 193Typhus pellagrosus, 301, 321Tyrosin, 30, 31, 32, 34-, 5&> *7tft)ler kiitistliche Erndkrung undVUaminr,UHLMANTN, 78, 143, 144, 358, 362, 378T J N , see EPPIKGER

Ultraviolet Light, 120, 229, 264UMBER, 389UMMES, 309, 310, 345UNDERBILL, 73,356; see also CHITTENDENUNGER, see HESSUnited States Lead in dietetic Experi-

ments, 323United States, Investigations regarding

t Nutrition, 172United States, Investigations regarding

Etiology of Pellagra, 306, 307United States, Pellagra in, 305, 306, 307,rT . 313-315, 320-321University Cream, 236Uracil, I2rURBEANU, 72, 102, 205, 304, 310, 318,

320, 321,338,354Unc Acid, 121Urine in Beriberi, 130, 131Utilisation ; see also Assimilation.Utilisation of Calcium in various forms

of Administration, 92—94

Valin, 29, 33, 49VALIARDI, 307, 342Variety in Diet, 47, 176, 177,191, 221 ;

see also DietYEDDER, 102, 109, 134, 136, 345, 354,

356, 361; see also CHAMBERLAIN,ROMMEL

YEDDER and CLARK, E., 129, 135, 157,

"VEDDER and "WILLIAMS, 113, 135, 346,

Vegetable Juice, fresh, 212Yegetable Meat, 50Vegetables, 327Vegetables as ultimate Source of A,

240Vegetables, "bleached, see Bleaching,

dried, 197, 230, 257, 261, 262, 278fresh, 189, 209, 243, 244, 246, 247, 24S,

250, 251, 262, 269, 278green, see G-reen VegetablesFa Spme, 215, 217Preparation of, see Boilingpreserved, 247, 280, 281Steaming, Scalding, and Bleaching of,

210, sri, 278Vegetarianism, 37, 73, 290VERMILZE, see MCCOLLUMVertigo, 300VERZAR, see STORM VAN LEEUWBNVERZAR and BSGEL, 142, 239. 380Vichy Water, 215VIDONI, see GATTIVIDONI and GATTI, 342Viennese Institute for Mothers and

Nurselings, 25aViennese University Clinic, 250Vignin, 48-49. *75Viaegar, 248, 252Vinegar as Cause of Acidosis, 77VISWALHTGAM:, 361, 371Vitamin Manual, The, 384Vitammes, Essential Food Factors, 9Vitamins, xoVitamins, Th€t 14, 389

414 VITAMINS

Vitamins and the Choice of Food, gVitamine, ihre Bedeutung filr die JPhysio-

logie und Pathologie, etc., 350Vitamin., Funk's see Funk's VitaminsVitamin, term, defined, 21 et seq.Vitamin and Vi.tain.ias, passim ; but see

also Funk's VitaminsVitamine, Die, yyVitellin, 52, 176V N , 116, ng, 157, 319, 350, 354,

355> 379 ; see also KOCH, MYERS,SULLIVAN

and LAKE, 364.N-, LAKE, and MVERS, 363

VtEGTLiN1 and MYERS, 144, 363, 366, 367VtEG-TLiN, NEILL, and HUNTER., 370VtEG-TLiNr and TOWLES, 135, 346VtEGTLiN- and WHITE, 117, 356VtE&TLiN and HARRIS, 370VtEG-TLiN, SULLIVAN, and MYERS, 375V*GT, 250,372VfIT, 26, 102VtLPiNO, 3O7, 310, 311, 312, 348, 349VtLPiNO and BORDONI, 312, 352V BORDONI, and ALP AGO-NO-

VELLA, 343PiNO, MARIANI, BORDONI, and AL-PAGO-NOVELLA, 343

WAELE, 277, 278, 377WAKEMAN, set OSBORNEWALLIS, 10I, 360WALSHE, 360, 370Walnuts, 50, 191, 224, 329WANG, see BLUNTWai Psychosis, 281WARING, see GOLDBERGERWartime Feeding, 431, 271

as cause of malnutritional Oedema, 278Wartime Feeding of Children in Germany

and German Austria, 210-212Wartime Feeding of U.S. Soldiers in

Trenches, 268WASON, 385Wasting, see EmaciationWatercress, 330WATERS, 340Water-soluble B, see B

C, see CD, seel)

WATSON, A. F., see DRTJMMONDWATSON, A. H., see PATONWATSON, C, and HUNTER, 339Wax, 186Weakness, see DebilityWEBSTBR, see EDIEWeight, Body, see Emaciation

Arrest of Increase, 297, 298, 321Weight, Increase of, 173, 200Weight, Loss of, see Emaciation

Maintenance of, 175-176, 178,179,188,199, 208, 222, 231

WEILL and MOURIQUASTD, 106, 107, 119,137, 251, 353, 354, 357, 358, 359,361, 362, 363, 365

WEILL, MOURIQUAND, and MICHEL, 353WEILL, MOURIO,UAND, and BERONNET,

361

WEISER, 108, 234, 345, 348Weisser Hirsch, 211WELLMAN, BASS, and EUSTIS, 344"WELLMAN, EUSTIS, and SCOTT, 346WELLMANN and EUSTIS, 104WELLS, A. H., 364, 383WELLS, H. G., 386WELLS, C. A., and EWING, 355WELTMANN, 381WERTHEIMER, see ABDERHALDENWERTHEIMEER and WOLF, 386WETZEL, see SOLLMAHNWhale Oil, 225, 331Whalers, Scurvy among, 243Wheat, 44-4-5, 52, 54,55, 58, 59> 108, 140,

176, 181, r86, 191, 200,223, 253, 305,314, 315, 328, 329

Germ, 119,140,176, 181,186,191, 223,225, 327, 328, 332

Wheatmeal, 192, 328WHEELER, A. G., see G-OLDBERGERWHEELER, L., see SHERMANWHEELER, R., 346,352WHEELER, R., and BIESTER, 349Whey, 186WHIPPLE, B. K., 141, 192,196, 381WHIPPLE, G. H., see HOOPERWHIPPI-E, G. H., and VAN SLYKE, 751 361WHITE, see VOEGTLINWhite Flour and White Bread, see Flour

and Bread respectivelyWhite of Egg, 53, 55, ro3, 328 ; see also

OvalbiiminWholemeal, 280, 328WlELAlSD, 344." Wiener klinische Wochenschrift," 286WILBUR, see ANDERSONWILLAMAN, 240, 372WlLLCOX, IOI, 125, 144, 24.6, 247, 248,

253, 354, 358, 371WlLLETS, See GOLDBERGERWILLIAMS, A. W.} and POVITZKY, 385WILLIAMS, LEONARD, 12WILLIAMS, R. H., see EMMETWILLIAMS, R. J., 194, 368, 375, 384WILLIAMS, R. R., 122, 123, 353, 354,

355, 358, 387; see CHAMBERLAIN,VEDDER

WILLIAMS, R. R., and CROWELI,, 351WILLIAMS, R. E.., and JOHNSTON, 351WILLIAMS, R. R., and SALEEBY, 351WILLIAMS, R, R, and SEIDELL, xi4, 118,XXT ™*> 136, 356WILSON, 387WILTSHIRE, 249, 363, 381WINFIELD, 361WINTERS, see SHERMANWINTZ, 52, 175,355WITHERS and CARRUTH, 359WOLF, see WERTHEIMERWOLLMAN, 366, 369Wool-eating, 70-71WRIGHT, 339WITTH, 366WYON, see MCLEOD, J. W.X Acid, 21, noXan thiii, 121

INDEX 415Xanthophyll, 228Xerophthalmia, 227, 231-233, 240, 241,

254, 297YAMIGAWA, KOYAMA, MIDORIKAWA, and

MOGI, 105, 345

YATES, see SHERMANYeast, 36, 50, 52,113, 114,115, 119,120,

121,134., 135,136,137,13S, 139,140,141,186,187,193,194,195, 197,255,3O5, 331

nutritive, 174, 175Protein, 1:75Vitamin, 122

Yeast-nucleinic add, 121, 156Yeasts can synthetise A, 240Yolk of Egg, 53,138, 178, 220, 221, 222,

225, 295, 328 ; see also VitellinYolkless Eggs, owing to Calcium De-

ficieac7 in Fowls' Diet, 72

ZADIK, 97, 33 8ZAMBRZYCKI, 283, 376Zein, 43, 59, 176, 311, 312, 313Zeism, 316" Zentralblatt fur Biochemie und Bio-

physik," 284Zeochin, 308-310, 313, 321Zetror, 261ZILVA, 120, 199, 224, 227, 229, 264, 367,

376, 382, 384 ; see also DRUMMOND,HARDEN

ZILVA and MITJRA, 384, 386, 389ZILVA and STILL, 376ZILVA and WELLS, F, M., 366ZILVA, GOLDING, DRUMMOND, and

COWARD, 386Zinc, 67 et seq., 332ZOETHOUT, 82, 366ZONDEK, see MAASEZXINTZ, 72, 80, 205, 2O6, 365, 370ZUNZ, 376