A SWIVEL THATHOLDS - ScienceIn press-ready in September The most complete work of its kind ever published, this handbook constitutes an invaluable text and reference book covering

JULY 27, 1945 SCIENCE-ADVERTISEMENTS 9

A SWIVEL THAT HOLDS

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JULY 2 7, 1945 SCIENCE-ADVERTISEMENTS 9

SCIENCE-SUPPLEMENT VOL. 102, No. 2639

SCIENCE NEWSScience Service, Washington, D. C.

THE CONTROL OF AIR TRAFFICEXTENSIVE planning is now under way by officials con-

cerned with LaGuardia Field on Long Island, New YorkCity's great airport, for controlling sky traffic because ofthe enormously increased use of the field expected inpostwar days. This means particularly radio communica-tion with approaching planes, instructing them relative toweather conditions, what air levels to use, and when andwhere to land.LaGuardia field is now one of the largest and busiest

traffic control centers in the world, according to the U. S.Civil Aeronautics Administration. But, it says, a tre-mendous increase in business after the war may be ex-

pected, and preparations for it must be made now.

"New York's problem is complicated," the Adminis-tration states. "Here, at LaGuardia Field, is a mixtureof foreign traffic entering the streams of domestic trafficcoming from every part of the continent centering at thecountry 's greatest metropolis. New York is now, and willbe increasingly, the terminus for intercontinental traffic. "

Controlling sky traffic becomes increasingly importantin bad flying weather. When instruments were developedto enable pilots to fly through storms and cloudy weatherconditions, traffic control along the airways became neces-

sary. Now, -with many planes in the air in all kinds ofweather, and scores converging on a spot like New Yorkand other great American fields, the pilot must be helpedto the ground.The pilot must be given information by radio relative

to weather conditions and landing conditions, and mustbe instructed at which thousand-foot level to approach,when to drop a thousand feet to a lower level, and whenand on which strip to land. Three kinds of governmentworkers perform these services, air traffic controllers,meteorologists and aircraft communicators.

These men rarely see the planes whose progress theychart and direct along the airways of the world. They sitbefore inclined posting boards with movable- cards on

which are recorded radio reports of planes received from

pilots when miles away. As the planes approach the cards

are moved downward on the board, and off the board when

the plane lands.New York's station handles both overseas-foreign and

interstate-domestic communications, distinguishing it

from others of the 400 stations operated by the Civil

Aeronautics Administration. The big gun of the stationis the intercontinental transmitter WSY at Sayville, LongIsland. All overseas communication is handled by the

administration.

ITEMS

THE amount of ascorbic acid, or vitamin C, in tomatoes

-the most important vitamin of this fruit-varies di-

rectly with the light intensity in the growing areas, is

indicated by studies in the U. S. Plant, Soil and Nutrition

Laboratory of Cornell University. Of this discovery, Dr.

L. A. Maynard, director of the laboratory and head of

Cornell 's School of Nutrition, said, " investigators be-lieve that it will be worth while to chart areas where

commercial production will yield the highest vitamin con-

tent in this important food." In the tomato research.studies by Dr. W. L. Nelson showed first of all thattomatoes as marketed vary widely in their content ofascorbic acid. Dr. Karl C. Hamner and Dr. G. F. Somersethen found that most variations resulted from differencesin light intensity prior to harvest. In a recently com-

pleted study, the tomatoes grown in one area had one

third more ascorbic acid than the same variety grown inanother nearby area. A light-measuring device showedthat those grown in the first section were subject to one-

third greater light intensity.

INCREASING the family 's vitamin A consumption is goodfor young and old, it appears from studies of rats re-

ported by Dr. H. C. Sherman and Dr. H. L. Qampbell, ofColumbia University, to the National Academy of Sci-ences. Liberal intakes of this vitamin, found in such

foods as butter, liver, egg yolk, carrots and green leafy-vegetables, tends to postpone aging and increase lengthof life, Dr. Sherman and colleagues have previously re-

ported. Now they find that the offspring in rat families-on the liberal vitamin A intake grow somewhat more-

rapidly and with less individual variability. This indicates that liberal vitamin A has both a favorable and a

stabilizing influence on growth. This favorable, stabiliz-ing effect on rat growth was observed with vitamin Aintakes two and four times higher than the intake con-

sidered fully enough to meet the rat 's nutritional needs-

USE as a water softener of New Jersey marl or green-

sand, formerly important as a fertilizer, has inspired ar

program of rehabilitation and expansion for New Jersey 's

mineral industry which has dwindled in output, incomeand employment in recent years. A new bureau of min-eral research at Rutgers University, headed by Dr. AlfredK. Snelgrove, formerly of the Michigan College of Mining:and Technology, will conduct the study.

GROWING plants in glass flowerpots will feed on the-walls of the pots themselves if they are made of a new

nutrient glass fertilizer. The glass will supply all the-necessary food elements except nitrogen, organic matter-and water. This use is suggested by A. E. Badger andR. H. Bray, of the department of ceramies engineering.of the University of Illinois, as one of the results of workcarried on on the solubility of fused mixtures of rockphosphate, potassium carbonate and silica. Should propersolubilities be obtainable with the more complex mixtures,.these scientists state, and costs be competitive with pres-ent fertilizers, glass fertilizers may offer interesting ad-

vantages. The ease with which glass can be manipulated,.the scientists say, suggests many commercial adaptations;for soilless growth experiments as well as ordinary appli-cations for soil enrichment.

10


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THE CHEMISTRY OFNATURAL COLORING MATTERSBy FRITZ MAYERFormer Professor of Chemistry, The University of Frankfort-on-MainTranslated and Revised by A. H. COOK,Department of Chemistry, Imperial College of Science, LondonThis unique and masterly treatise presents a vast amount of essential data onthe constitution, physical constants, structures, and functions of all the knownpigments and related substances. In easily accessible form, the extensivelydocumented basic information should prove of greatest interest to biochem-ists, dye technicians, and students of organic structure.354 Pages A.C.S. Monograph No. 89 $10.00

SOILLESS GROWTH OF PLANTSBy CARLETON ELLIS and MILLER W. SWANEY

Today's tremendous success in U. S. Army research and experiment proj-ects in the science of hydroponics places increasing emphasis on this im-portanit new science. SOILLESS GROWTH OF PLANTS, the first book writtenon this subject, has won outstanding recognition in this rapidly expandingfield. It explains and describes all phases of Soilless Growth-Water Cul-ture Sand Culture and Sub-Irrigation.160 Pages 60 illustrations-3 in color $2.75

BIOCHEMISTRY of the FATTY1ACIDSand Their Compounds, The LipidsBy W. R. BLOORProfessor of Biochemistry and Pharmacology,The University of Rochester, Rochester, N. Y.

A dynamically important study of the vital group of substances included inthe term "fatty acids," this comprehensive critical review is of inestimablevalue to those in the food and pharmaceutical fields, including physicians,nutritionists, organic chemists and biochemists.387 Pages Illustrated . $6.00

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12 SCIENCE-ADVERTISEMENTS VOL. 102, No. 2639~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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*WERTHEIMLaboratory Guide for Organic Chemistry

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* WERTHEIMExperiments in Organic Chemistry

34 Illus. A sufficiently large number of experiments are provided in this book to221 Pages allow considerable variation of the work as the course is repeated. A

$1.35 number of biochemistry experiments are included. Helpful questionsare given within the laboratory directions and others are added in a sepa-rate group. The average time needed for each experiment is indicated.By E. WERTHEIM, PH.D., University of Arkansas

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This book pioneers in presenting a concise, practical account of the far-682 Pages reaching and important advances in analyses that have been made with

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* HACKI-GRANTChemical Dictionary. 3rd Edition

217 Illus. The extensive progress in all branches of chemistry and related sciences925 Pages is fully represented in this new edition of Hackh. The plan and scope

$12.00 of the book is to provide concise, intelligible definitions based on the latestresearch findings and current acceptations. Numerous original tablesand illustrations are included.Revised by JULIUs GRANT, M.So., PH.D., F.R.I.C.

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12 SCIENCE-ADVERTISEMENTS VOL. 102, No. 2639


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MANUAL OF CHILD PSYCHOLOGYEdited by LEONARD CARMICHAEL, President and Director ofthe Laboratory of Sensory Psychology and Physiology, Tufts College

BRIDGING the gap between elementary textbooks andthe scientific periodical literature of. psychology, this is CONTENTSan advanced bibliographical survey of the literature on Methods of Child Psychol-child development now available. It presents an accurate ogy * The Onset and Earlypicture of the field of child psychology and evaluates the Development of Behavior6result of research in the scientific psychology of human Animal Infancy 0 The Ado-lescentS0 The Feeble-Mindeddevelopment. Child * The Ontogenesis of

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Sex Differences S PhysicalGrowvth@* Index:.T HIS handbook of reliable facts, established theories,Growth __Index.

techniques and methodology is presented as a series ofseparate chapters, each written by a recognized authority.The book is designed for the -use of serious advanced August 1945undergraduate students and graduate students as well as Approximately 1459 pagesfor specialists in psychology and in such related fields aseducation, psychiatry, pediatrics, and medicine in 6 1/8 by 8 9/16general. Probable Price $6.00

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The most complete work of its kind ever published, thishandbook constitutes an invaluable text and referencebook covering the entire field of meteorology, and pre-senting a wealth of authoritative information needed byboth the beginner and the expert. Among 'the topics

dealt with are mathematics; thermodynamics; physics ofthe air; radiation; descriptive meteorology; climatology;dynamic meteorology; instruments; codes, maps, andplotting; synoptic meteorology and weather forecasting;oceanography; and hydrometeorology.

Wave Propagation in Periodic Structures. Electric Filters and Crystal LatticesBy LEON BRILLOUIN, Columbia University. In press-ready in September

This important new volume incorporates a variety ofproblems, linked by their common mathematical back-ground, extending from electrical engineering to electro-magnetism and wave mechanics of the spinning electron.

All problems discussed deal with periodic structures ofvarious kinds, which, whether they are electric lines orcrystal lattices, behave like band-pass filters. A generaldiscussion of the zone theory is presented.

Transmission Lines, Antennas, and Wave GuidesBy RONOLD W. P. KING, HARRY ROWE MIMNO and ALEXANDER H. WING, Harvard University.347 pages, 54 x 84, 214 illustrations. $3.50

In this book the authors present, with some additions, the versity. Transmission lines are presented exclusivelymaterial given in the lectures on transmission lines, an- from the high frequency point of view; antennas fromtennas, wave guides, and wave propagation, constituting the point of view of electromagnetic theory; and wavepart of a course of instruction in preradar training for guides from the point of view of generalized transmissionArmy-Navy officers, at Cruft Laboratory, Harvard Uni- circuits.

Electromagnetic Engineering. Vol. 1.-FundamentalsBy RONOLD W. P. KING. Radio Communication Series. 580 pages, 5i x 84, 76 illustrations.$6.00

The first of a series of three volumes, this book gives asystematic introduction to those basic concepts of electro-magnetism that are fundamental in the study of electro-magnetic waves, antennas, electromagnetic horns, wave

guides, and ultra-high frequency and microwave circuits.The physical and mathematical essentials of electrody-namics are logically developed and critically discussed.

Introduction to Industrial ChemistryBy W. T. FRIER, General Electric Company, and ALBERT C. HOLLER, United States MetalProducts Company. In press-ready in August.

In this new book two industrial chemists provide an ex-ceptionally clear and interesting elementary text, espe-cially suitable for use in training classes *ithin industry,and, in general, with students of limited scientific back-

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McGRAW-HILL BOOK COMPANY, INC.330 West 42nd Street, New York 18, N. Y.


Aldwych House, London, W.C.2.

SCIENCE-ADVERTISEMENTS

-INTERSCIENCE SERIESiADVANCES IN NUCLEAR CHEMISTRY AND THEORETICAL ORGANIC CHEMISTRY-Frontiers in Chemistry, Volume Ill

Edited by: R. E. BURK, E. I. du Pont de Nemours & Co., Wilmington, Del. andOLIVER GRUMMITT, Western Reserve University, Cleveland, Ohio.

1945 6 x 9 178 pages 39 illustrations $3.50

CONTENTS: ALBERT S. KESTON, New York, N. Y., "Isotopes and Their Applica-tions in Biochemistry"; H. S. TAYLOR, Princeton, N. J., "Applications of Istotopes inCatalytic Reactions at Surfaces"; H. R. CRANE, Ann Arbor, Mich., "Techniques inNuclear Physics"; L. G. S. BROOKER, Rochester, N. Y., "Resonance and OrganicChemistry"; W. H. RODEBUSH, Urbana, Ill., "The Hydrogen Bond and Its Signi-ficance to Chemistry'.

ADVANCES IN ENZYMOLOGY, VOLUME V

Edited by: F. F. NORD, Fordham University, New York, N. Y. and C. H. WERK-MAN, Iowa State College, Ames, Iowa.

1945 6 x 9 268 pages 11 illustrations $5.50

CONTENTS: N. W. PIRIE, Harpenden, Eng., "Physical and Chemical Properties ofTomato Bushy Stunt Virus and the Strains of Tobacco Mosaic Virus"; E. CHAR-GAFF, New York, N. Y., "The Coagulation of Blood"; H. BLASCHKO, Oxford, Eng.,"The Amino Acid Decarboxylases of Mammalian Tissue"; J. LEIBOWITZ and S.HESTRIN, Jerusalem, Palestine, "Alcoholic Fermentation of the Oligosaccharides";E. STOTZ, Geneva, N. Y., "Pyruvate Metabolism"; F. F. NORD, New York, N. Y.and R. P. MULL, Summit, N. J., "Recent Progress in the Biochemistry of Fusaria";F. SCHLENK, "Enzymatic Reactions Involving Nicotinamide and Its Related Com-pounds"; C. V. SMYTHE, "Some Enzyme Reactions on Sulfur Compounds."

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JULY 27, 1945 is


EXPERIMENTAL BIOLOGY MONOGRAPHS

This important series of scientific monographs constitutes. a cumu-lative library on research in the various branches of the biologicalsciences in which substantial progress is being made. Each ofthe volumes listed below is written by an active worker, or work-ers, in its field; and presents a summary of the experimental con-tributions to that field and discusses in detail the theoretical im-plications of important experimental findings.

PHYTOHORMONESBy F. W. Went, Calif. Inst. of Technology & K. V. Thimann, Harvard Univ.294 pages Illustrated $4.00

THE EGGS OF MAMMALSBy G. Pincus, Harvard University

160 pages Illustrated $3.75

VERTEBRATE PHOTORECEPTORSBy S. R. Detwiler, College of Physicians and Surgeons, Columbia Univ.


AUTONOMIC NEURO-EFFECTOR SYSTEMSBy W. B. Cannon and A. Rosenblueth, both of Harvard University


NEUROEMBRYOLOGY. AN EXPERIMENTAL STUDYBy S. R. Detwiler


PACEMAKERS IN RELATION TO ASPECTSOF BEHAVIOR

By H. Hoagland, Clark University138 pages Illustrated $3.00

DYNAMICS OF INFLAMMATIONBy Valy Menkin, Harvard University Medical School


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POSITIONS OPENLeading manufacturer of ethical products in Chi-cago has opening for man capable of directing allquality control work. Chemical training and ex-perience in quality control as applied to processindustries desired. Must have proven ability toorganize and direct work of this type and to workwell with other departments. Send details oftraining, experience, and personal data with firstletter. Box 184, "ScIENCE," Smithsonian Insti-tution Building, Washington 25, D. C.Biochemist for research on quantitative incidenceof certain enzymes in the brain. Salary $2500less government deductions. Write W. AsBYr,Saint Elizabeths Hospital, Washington.Medical Bacteriologist: teaching and research posi-tion, department of bacteriology, class A medicalschool, east. Ph.D or M.D. required. State quali-fications and experience. Box 187, " SCIENCE, "Smithsonian Institution Building, Washington 25,D. C.WANTED by southern state university: Two zool-ogists-one with teaching interests in physiology,the other in vertebrate zoology. Must have Ph.D.degree and interest in doing research as well asteaching. Young men preferred. Salary and rankcommensurate with training and experience of per-sons appointed. Box 190, "ScIENcE," Smith-sonian Institution Building, Washington 25, D. C.

Opportunities Avallable-(a) Pharmacologist andmanufacturing chemist, experienced with veterinaryproducts; one of the leading companies in the fieldof veterinary medical supplies; $3600-$4000. (b)Young man trained and experienced in medicalschool physiology with research interest in bio-chemistry; Eastern university. (c) Physicist tohandle lectures, recitations and laboratory work inelementary college physics; teaching experiencepreferably at college level required; work largelywith Marines and men of the Navy in the V-12program and academic refresher unit; East. (d)Bacteriologist to head bacteriological control, largecompany important in pharmaceutical industry;preferably some one with major in bacteriology andminor in chemistry; Middle West. (e) Directorfor new antibiotic department; Ph.D. with gradu-ate training in bacteriology and biochemistry andexperienced in field of antibiotics required; new

pilot plant and research quarters; duties involve di-recting work of ten persons; $5,000; Middle West.(f) Young physician to head professional servicedepartment, export division, large pharmaceuticalcompany; duties administrative including someeditorial work; knowledge of foreign languages,particularly Spanish, Portuguese or French ad-vantageous; interesting post-war possibilities;headquarters in Chicago. S7-3 Medical Bureau(Burneice Larson, Director) Palmolive Building,Chicago 11.

POSITIONS OPENPhysical Chemist or Physicist for x-ray difErac-tion research on protein -fibers. Work is funda-mental, classified as essential, will continue afterwar. Training in exact field desirable but not re-quired. Send personal data, professional qualifiea-tions, references, photo, salary required, availabilityin first letter. Address Dept. of Biology, Mass.Inst. Technology, Cambridge, Mass.

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POSITIONS WANTED

Biochemist: 35, Ph.D. Nine years industrial ex-perience, enzyme and protein technology. Nowhead of small department. Wishes similar positioninvolving research and/or administration in ex-panding organization. Box 188, "SCIENcE,y"Smithsonian Institution Building, Washington 25,D. C.

College Administrator-Available to coordinateoffices of admissions, examinations, registrar, deansof men, women, and veterans' counselling. Ex-perienced teacher with Ph.D. Wide industrialcontacts. Writer and speaker. Box 185 "Sci-ENCE," Smithsonian Institution Building, Washing-ton 25, D. C.

Pharmacologist (Dental) seeks assistant professor-ship in dental school; B.S., D.D.S. degrees; gradu-ate work in pharmacology; instructor large easternuniversity, teaching experience dental and medicalschool. Box 192, "SCIENCE," Smithsonian Insti-tution Building, Washington 25, D. C.

Physiologist (officer in service) desires contactsfor post-war employment. Broad background,research and teaching experience. Box 189,"SCIENCE, " Smithsonian Institution Building,Washington 25, D. C.

Theoretical Physicist, longtime Associate of Re-search Institute of large Western European Uni-versity; long experience in research and over eightterms of teaching experience in large Eastern Col-lege, engaged in war research, available for teach-ing next Fall. Preferably West Coast and Institu-tion where, in postwar period, research in Physicsis planned. Box 191, "SCIENCE," SmithsonianInstitution Building, Washington 25, D. C.

Opportunities Wanted-Malariologist is available;B.S. in Biology; M.S. in Protozoology; Ph.D. inBacteriology and Parasitology; two years instructorand professor of biology, small college; while en-gaged in graduate work served as assistant in de-partment of bacteriology and parasitology; expectsearly discharge from Army after three years withSanitary Corps; work has been principally inmalaria survey and control; has distinguished him-self in the field of research. For further informa-tion, please write Burneice Larson, Director, Palm-olive Building, Chicago 11.

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Features each month* Nine original articles interpreting theprogress of science each written by anauthority on the subject.

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* Comments and Criticisms. AForum for scientists and laymen topresent personal views about science.

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The Scientific Monthly is used in schoolsand libraries as a source of accurate andauthoritative information. Scientists useit to keep abreast of progress in fields otherthan their own and laymen enjoy its widecoverage of all the fields of science.

Edited and published by the AMERI-CAN ASSOCIATION for the ADVANCE-MENT of SCIENCE, a world-wide organi-zation of over 27,000. Members of theAssociation in good standing currently re-ceiving SCIENCE may subscribe to TheScientific Monthly for $3 additional. Non-member subscription for the calendar yearonly, $5.00; single numbers, 50 cents. Sub-scriptions beginning at times other thanJanuary, $6.00 per year. Sample copiesupon request.



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20 1SCIENCE-ADVERTISEMENTS VOL. 102, No. 2639

Documents

A SWIVEL THATHOLDS - ScienceIn press-ready in September The most complete work of its kind ever published, this handbook constitutes an invaluable text and reference book covering