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Page 1: RESEARCH...PHOTOVOLT Line-operated Electronic pH METER ATruly Universal Instrument * for laboratory andindustrial application * fcr all types anddesigns of electrodes * fcr pH, titration,

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Page 2: RESEARCH...PHOTOVOLT Line-operated Electronic pH METER ATruly Universal Instrument * for laboratory andindustrial application * fcr all types anddesigns of electrodes * fcr pH, titration,

Rat U.5.a. 9

CRYSTAL L I NEAMINO ACIDS

Availablefor

Nutritional Research

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Writefor complete price list.

60 LABORATORY PARK * CHAGRIN FALLS, OHIO

LaboratorY Prei-Testfor MicrobiologiclUe

"Vitamin Free" Casein Hydrolysate GBI-(acid hydrolyzed) for U.S.P. and otherstandard assays for B-complex vitamins,amino acids and bacterial nutrition studies.100 cc. serum bottles-$18.00 per dozen.

"Special" Casein Hydrolysate GBI-same asabove product but more economical to usefor all those procedures where its content oftrace quantities of niacin will not interfere.100 cc. serum bottles-$15.00 per dozen.

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Our various strains of mice, rats and guineapigs all carry the identifying initials "CF"-Carworth Farms.

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Page 3: RESEARCH...PHOTOVOLT Line-operated Electronic pH METER ATruly Universal Instrument * for laboratory andindustrial application * fcr all types anddesigns of electrodes * fcr pH, titration,

A JOURNAL OF SCIENCE

A JO URNAL OF SCIENCEAND ITS APPLICATION

RESEARCHSCIENTIFIC ADVISORY BOARD:

The Rt. Hon. Sir John ANDERSON, G.C.B., F.R.S., M.P. (Chairman)Sir Wallace AKERS, C.B.E.

DIRECTOR OF RESEARCH I.C.I. AND LATELYDIRECTOR OF ATOMIC ENERGY RESEARCH UNDER

THE DEPARTMENT OFSCIENTIFIC INDUSTRIAL RESEARCH.

Sir Charles DARWIN, K.B.E., M.C., F.R.S.DIRECTOR, NATIONAL PHYSICAL LABORATORY.

Sir Alfred EGERTON, F.R.S.PROFESSOR OF CHEMICAL TECHNOLOGY,

IMPERIAL COLLEGE OF SCIENCE.

EDITOR:Dr. Paul ROSBAUD.

Issued montky First issue: Octber, 1947

Sir Alexander FLEMING, F.R.S.PROFESSOR OF BACTERIOLOGY IN THE

UNIVERSITY OF LONDON.

Professor R. S. HUTTON, D.Sc. (Secretary)LATELY PROFESSOR OF METALLURGY IN THE

UNIVERSITY OF CAMBRIDGE.

Sir Edward SALISBURY, C.B.E., F.R.S.DIRECTOR OF ROYAL BOTANIC GARDENS, KEW.

DEPUTY EDITOR:D. R. REXWORTHY.

Subscription *10.00 yerly Poaefre

This new British journal is a pioneer among high-level scientific publications. Inselecting contributions with the view to the applicability of the results of pure scientific re-search, covering the broad front of science, it is not limited by subject matter, but purpose-fully and practically serves as a functional link between specialized scientific research andIndustrial development and technological progress.

In addition to articles, reviews of recent scientific work and practical applications,reports from industrial laboratories and academic establishments of applied science, and bookreviews, RESEARCH will contain a supplement for the publication of original research paperswhich combine the results of fundamental science and technical progress.

Published by BUTTERWORTH SCIENTIFIC PUBLICATIONS, London

Sole Agent for the United States of America:INTERSCIENCE PUBLISHERS, Inc., 215 Fourth Ave., New York 3, N. Y.

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Page 4: RESEARCH...PHOTOVOLT Line-operated Electronic pH METER ATruly Universal Instrument * for laboratory andindustrial application * fcr all types anddesigns of electrodes * fcr pH, titration,

youare seeking

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see this issue page 19

WE TRY TO MAKEPERFECT

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Page 5: RESEARCH...PHOTOVOLT Line-operated Electronic pH METER ATruly Universal Instrument * for laboratory andindustrial application * fcr all types anddesigns of electrodes * fcr pH, titration,

Order these books now for Free ExaminationPRINCIPLES OF FOOD FREEZING

by W. A. Gortner, Assoc. Professor of Biochemistry, F. S. Erdman, Assoc. Professor ofMechanical Engineering, and Nancy Masterman, Research Associate in Home Economics.L.A. Maynard,ProfessorofNutrition andBiochemistry (Editor). All at Cornell University.

This book is the result of the collective efforts of a biochemist, a mechanical engineer and a homeeconomist. It deals with all aspects of food freezing from the raw material to the finished productas it goes to the consumer's table. Major attention is given to farm, home and community equip-ment, their suitability for various jobs, and the problems involved in their use. Basic principlesare stressed regarding equipment and handling of foods. The book explains biochemical and nutri-tional aspects of freezing, cooking and storage, and engineering principles of the construction andoperation of equipment. Opposing viewpoints are given and references cited to aid food packers,locker operators and homemakers. From the preface-"the book should not only prove useful toall individuals concerned but it should also help in the promotion and evaluation of this compara-tively new method of food preservation which may well prove to be a large contribution to betternutrition and health."

approx. 262 pages probable price, $3.50

PLANTS AND ENVIRONMENT

by R. F. Daubenmire, Assoc. Professor of Botany, State College of Washington.A detailed exposition of the basic principles of autecology, with special attention given to applied

ecology. This book cuts across many specialized fields, showing how research in those fields is tiedtogether. This is the first ecology book to give special consideration to adaptation and ecologicevolution. Illustrations are taken from a wide area, and references are inserted liberally throughoutthe book. Conflicting terminology, the despair of ecologists, is eliminated. Chapter headings:Soil Factor, Water Factor, Temperature Factor, Light Factor, Atmospheric Factor, Biotic Factor,Fire Factor, Environmental Complex, Ecologic Adaptations and Evolution.

February 1948 approx. 385 pages probable price, $4.00

INTRODUCTION TO GENETICSAND CYTOGENETICS

by HerbertLP. Riley, Professor and Head ofthe Department of Botany, University ofKentucky.

This book features the chromosomal ap-

proach to genetics. Genes are treated as unitslocated in the chromosomes. The book beginswith a discussion of cells, points out chromo-somes and genes, and then treats mendelianinheritance as a function of chromosomebehavior. All material is presented logicallyrather than historically. Some elementarybiology is included for review purposes. Plantand animal material is treated with no over-emphasis of either. There is an extensivediscussion of blood groups, of great importancein the study of genetics.

January 1948 approx. 580 pagesprobable price $4.50

FUNDAMENTALS OFPHOTOGRAPHIC THEORY

by Thomas H. James and George C. Hig-

gins, both of Eastman Kodak ResearchLaboratories.

A general account, based on fundamentalchemical and physical concepts. The greaterpart of the book is devoted to that portion ofthe process which involves the use of silversalts. No attempt is made to treat lens designor camera construction, these being separatesubjects. Basic knowledge of physics andphysical chemistry is needed. The reader whois interested in any branch of the subject nottreated in the book will find ample material ingeneral references at the end of each chapter.

January 1248 approx. 290 pagesprobable price $4.00

JOHN WILEY & SONS, Inc., 440 Fourth Ave., New York 16, N. Y.

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Page 6: RESEARCH...PHOTOVOLT Line-operated Electronic pH METER ATruly Universal Instrument * for laboratory andindustrial application * fcr all types anddesigns of electrodes * fcr pH, titration,

PHOTOVOLTLine-operated Electronic

pH METER

A Truly Universal Instrument* for laboratory and industrial application* fcr all types and designs of electrodes* fcr pH, titration, and oxidation-reduction potentials* for all AC power lines 90-275 volts 50-60 cycles* available with or without portable wooden housing* furnished with shielded glass electrode, available also with

shielded compartment for unshielded electrodes

PHOTOVOLT95 Madison Ave.Also: Colorimeters

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LABORATORYEQUIPMENT

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LaMOTTE FIELD UNITFor Inspection of Food Stuffs

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Page 7: RESEARCH...PHOTOVOLT Line-operated Electronic pH METER ATruly Universal Instrument * for laboratory andindustrial application * fcr all types anddesigns of electrodes * fcr pH, titration,

The INTEISCIENCE ENCYCLOPEDIA, Inc.

ENCYCLOPEDIAof Chemical Technology

in 10 volumes

Edited by Raymond E. KIRKHead, Department of Chemistry,Polytechnic Institute of Brooklyn

and Donald F. OTHMERHead, Department of Chemical Engineering,

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$20.00 per volume

VOLUME I

A to

Anthrimides

This Encyclopedia is designed to present the en-tire field of chemical technology to professional chemistsand chemical engineers in industry and at universitiesand other research institutions.

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Topics technologically related to each other aregrouped together. Individual compounds of consider-able technical importance, however, are treated inseparate articles.

Preference has been given to American practices,but deviations from these have been mentioned, wherea foreign practice seemed to offer advantages of gen-eral interest. All articles have been written by spe-cialists in each field from the American chemical indus-try and other research institutions.

Send orders or requests for detailed information to Dept. S

INTEISCIENCIE PIDLISHE1IJS, Inc., 215 Fourth Ave., New York 3, N. Y.15

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Page 8: RESEARCH...PHOTOVOLT Line-operated Electronic pH METER ATruly Universal Instrument * for laboratory andindustrial application * fcr all types anddesigns of electrodes * fcr pH, titration,

HOTEL RESERVATIONS"-Gus- 114th AAAS MEETING

Chicago, December 26-31, 1947

The list of hotels and the reservation blank below are for your convenience inmaking your hotel room reservation in Chicago. Your application is to be sent,not to the hotel directly, but to the AAAS Reservation Center in Chicago for clear-ance and assignment. Mailing your application now will be of material assistancein securing hotel accommodations.

HOTELS AND RESERVATION PRICES

HOTEL SINGLE DOUBLEDouble Beds Twin Beds

Bismarck $5.00 to $8.50 $8.50 to $12.00

Blackstone 12.00 to 13.00

Congress $4.00 to $10.00 6.00 to 12.00 7.00 to 9.00

LaSalle 4.00 to 7.00 5.00 to 8.50 8.50 to 10.00

Morrison 3.25 to 6.50 5.00 to 8.00 7.00 to 8.50

Palmer House 4.00 to 9.00 7.50 to 11.50 8.00 to 14.50

Sherman 3.95 to 8.95 5.95 to 10.95 6.95 to 10.95

Stevens 4.00 to 9.00 6.40 to 11.00 8.00 to 12.00

Some suites will be available ... $14.00 to $25.00 per day

-----This is your HOTEL RESERVATION BLANK * Mail now- ------

AAAS Reservation CenterChicago Convention Bureau33 North La Salle StreetChicago 2, IllinoisPle reserve the following accommodations for the AAAS Chicago Meetings. Attached findlistgiving name of each guest in my party.Hotel Type Accommodation DesiredFirst Choke ......... Single Room .............. Rate ............

I Double Room ........... Rate.Second Choice ......... Twin Bed Room.......... Rate ............

Suite ........... Rate.IThird Choice .......... No.in party......

Date of Arrival ......... Departure Date.......... (These must be indicated)SIGNED...............................................................................Street Address..........................................................................

City. .Zone .............. State .....................

Rooms will be assigned and confirmed in order of receipt of reservation

16

Page 9: RESEARCH...PHOTOVOLT Line-operated Electronic pH METER ATruly Universal Instrument * for laboratory andindustrial application * fcr all types anddesigns of electrodes * fcr pH, titration,

REGISTER NOWfor Chicago Meeting of A.A.A.S.

Dear Fellow Scientists:Since accepting the chairmanship of the Registration

Committee for the December 26-31 meeting of theAmerican Association for the Advancement of Science, I

have come to realize how important registering for themeeting will be. I am sure those of you who plan toattend the meeting will agree with me, particularly as toadvance registration, when you consider the followingconditions.

(1) At times 50 to 60 scientific sessions will be heldsimultaneously by the 15 sections of the Association andthe more than 50 cooperating societies. Therefore, sessionsmust be held in every important hotel in and near theLoop Area of Chicago. Your problem relative to thesessions will be-where, when, how to get there. TheGeral Program, issued only to registrants, gives all theanswers, and a Map. It will be indispensable, not onlyas a guide to the many sessions, but also, if you registerin advance, it will enable you to plan unhurriedly the bestuse of your time during the meeting.

(2) Even if you have the program in your own speci-alty, you will want to attend important sessions in relatedfields. Widening horizons are now characteristic ofscience as never before, and the Association meetingsprovide unparalleled opportunities for becoming ac-quainted with specialists in many fields. The GeneralProgram will give you the where, when, and how to getthere, with a great saving in time and taxi fares.

(3) You will want to find your friends during themeeting and you will want them to find you. Thatwill be no needle-in-the-haystack problem if you areregistered and have the General Program. The names

of those registered in advance of the meeting will be onthe Visible Directory, open for inspection adjacent tothe International Science Exhibition in the StevensHotel. The Visible Directory is also an invisible direc-tory, meaning that you can obtain the address, by ele-phone, of any person registered in advance for the.meeting. All you will have to do is telephone the at-tendant in charge of the Visible Directory at the StevensHotel.

(4) In addition to listing the titles of papers andauthors, the General Program will contain an index ofthe names and institutions of all persons on every pro-gram of the meeting. That is obviously something tokeep. Every person registering will have a copy of it.

There are other good reasons why you should register,but I will use the remaining space to ask you to fill inpromptly, carefully and fully the registration blank belowand send it now to theA A A S Office in Washington withyour check for the registration fee (see blank). You willthen receive your copy of the General Program early inDecember.

Cordially yours,HANs 0. HOEPPNERUniversity of Chicago

17

Registration Blank(Please type or print clearly)

A.A.A.S.1515 Massachusetts Avenue, N. W., Washington 5, D. C.

1. Registration Fee Enclosed (Check one)$2.00 A.A.A.S. Member D $3.00 Nonmember 0 $2.00 College Student 0

2. Name.......................................................................................3. Academic, Business or

Professional Connection. .....................................................................

4. Mail Address...............................................................................5. Your field of specialization ....................................................................6. Convention Address (if known)...............................................................

Page 10: RESEARCH...PHOTOVOLT Line-operated Electronic pH METER ATruly Universal Instrument * for laboratory andindustrial application * fcr all types anddesigns of electrodes * fcr pH, titration,

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A monthly publication com.piled for laboratory direc..tors, technicians and physi-cians. Full of essential factsand reviews of current literature on labora-tory procedure, professionally edited by R.B. H. Gradwohl, M. D., Sc. D. A neces-sity in the modern laboratory. Published by

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Write for Bulletins describing chemicals inwhich you are interested.

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Page 11: RESEARCH...PHOTOVOLT Line-operated Electronic pH METER ATruly Universal Instrument * for laboratory andindustrial application * fcr all types anddesigns of electrodes * fcr pH, titration,

Personnel Placement

POSITIONS WANTED

The California Medical Bureau, Agency for scientific and lay personnel inmedicine, biology, chemistry, physics and allied sciences, supplies teachers,research workers, laboratory dieners, skilled office help. Prompt service.Registration free. Your patronage respectfully solicited. Tuz Cawot-

MEDICAL BREAU, Agency, Arcade Medical Center, 696 ColoradoStreet, Pasadena 1, California.

Biologist: PhD 1931, woman, with experience in biochemistry, vitaminanalysis, endocrinology, animal work, teaching. Thirty publications; atpresent in charge of clinical nutrition research project; available Januarfirst for academic or industrial position; North Atlantic Seaboard preferred.

Box 124 A, SCIENCE.

Botanist: Man, 18 years experience, general botany undergraduate andgraduate morphology, research, good references. besires change withadequate salary and opportunity for research. Available June, 1948.Will make appointments at AAAS Chicago meetings. Box 119 A,SCIENCE.

Botanist: MS with three years toward PhD desires teaching position.Box 125 A, SCIENCE.

SoilChemist: young. Mastersdegree. Experience in laboratory analysis,soil moisture studies, field plot experimentation, and teaching. Box 126 A,SCIENCE.

Laboratory Technician: Young woman with AB in zoology. Experiencepreparing entomological exhibition cases for educational purposes. De-sires position in a museum of natural history. Box 127 A, SCIENCE.

Pharmaceutical research executive, now director of research in a pharma-ceutical company, is available for appointment offering greater opportuni-ties with full research facilities; PhC, PhG, degrees, and experienceequivalent to PhD; has developed several nationally-known products; isfully familiar with control methods and procedures and is experienced inwriting medical literature and technical bulletins; for further informationplease write Burneice Larson, Director, The Medical Bureau, PalmoliveBuilding, Chicago 11.

Zoologist: PhD; nine years teaching experience. Research interests;invertebrate zoology, parasitoloqy. Desire teaching position with sometime for research and opportunity for professional advancement. Willattend AAAS meetings. Box 128 A, SCIENCE.

POSITIONS OPEN

Bacteriologist: PhD, with specialized training in virology medical bac-teriolopy and immunology. Position is with the Researchiepartment oflarge blogical firm. Salary $400-4800. Box 113 A, SCIENCE.

Positions Ope: (a) Assistant professor in biochemistry; PhD with teach-ing experience and public research to his credit required; university medicalschool; Middle West. (b) Histologist to take charge of histo-pathologicallaboratories; research department of large industrial company; South.(c) Botanist for editorial position; duties include some research; $4000East. (d) Medical mycologist; qualified to diagnose pathogenic fungicausing diseases; duties include teaching; PhD or DSc degree; universitymedical school; South. (e) Neurophysiologist experienced in using theelectroencephalograph; PhD or medical degree required; opportunity ofconducting own research program; university medical school; East. (f)Pharmaceutical chemist to head department, college of pharmacy; middlewestern university; may report anytime between now and September 1948.(g) Manuscript editor trained and experienced in the fields of purely bio-logical sciences; large publishing company; opportunity for working intokey position. (h) Physiologist; PhD preferred, Masters degree eligible;experience in gastro-intestinal and cardio-vascular physiology desirable;duties consist of research and teaching interns and residents; large teachinghospital; MiddleWest. S11-4 Medical Bureau (Burneice Larson, Director)Palmolive Building, Chicago 11.

Personnel PlacementPOSITIONS OPEN

Economic Entomologist: To serve in technical service capacity for promi-nent manufacturer of insecticides and fumigants. Duties will includetechnical liason between sales, research and customers. Travel requiredfrom New York City base. Fundamental training in entomology andsome field experience required. Include resume of training, experience,personal data, salary requirements and recent snapshot, if avilable, inreply. Box 114 A, SCIENCE.

The Market PlaceBOOKS

WANTED TO PURCHASE SCIENTIFIC BOOKS AN PERODICANEntire libraries and smaller collections; sets and runs;

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Send us your Lists ofSCIENTIFIC BOOKS AND PERIODICALS

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CHARGES FOR CLASSIFIED ADVERTISINGRegular setting iog a word. Minimum charge $2.50 for each inser-tion. A box number counts as 8 words of the advertisement (e.g. 25words plus box number equals 33 words). Make checks payableto the A.A.A.S. All insertions must be accompanied by correctremittance and sent to the Adv. Dept. A.A.A.S. Please addressreplies as follows: Box number, ScrNcx, 1515 Mass. Ave., N.W.,Washington 5. D. C.

Index of Refraction Liquids for ImmersionMethods of Microscopy. Stable, non-volatile, cer-tified liquids 1.400 to 1.700; high index liquids,above 1.80 in preparation. Write for data S47-ND.R. P. Cargile, 118 Liberty St., New Yortk 6, N. Y.

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NOW AVAILABLE I

NEW NO. 6 CATALOG

The new No. 6 Catalog combines Catalog No. 5 and the CumulatedSupplement; in addition, it lists fifty new titles and later editionsof several titles.

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JL78300-Aloe-Willett Culture Tube CapsFor tubes,mm. 25 i8 i6 I3Size,mm..... 28X 30 25X20 22X I8 .20oXI5Per dozen.... $0.85 $0.80 $0.80 $0.75Per gross. 9.18 8.64 8.64 8.10

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School or Business Address

t;iitv E-nsp RtaMwbtowy

Page 14: RESEARCH...PHOTOVOLT Line-operated Electronic pH METER ATruly Universal Instrument * for laboratory andindustrial application * fcr all types anddesigns of electrodes * fcr pH, titration,

Dark-colored corpuscles, brilliantlines, and the subdued background ofthe Spencer Bright-Line Haemacyto-meter provide a strong contrast thatmakes cells easy to see and thereforeeasy to count accurately.Only the Bright-Line counting

chamber has a semi-transparent coat-ing of metal to eliminate glare, in-

crease visibility of the lines, and causecells to be more evefly distributed.An instructive booklet on the use

of the Haemacytometer is enclosedwith each chamber. If you do nothave a copy, write dept. Y3 for one.

American P OpticalCOMPANY

Scientific Instrument DivisionBufflo 15, New York