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INTRODUCTION TO COLORby Ralph M. Evans, in charge of Color Quality, Color Control Department, Eastman Kodak Company.

A fundamental study, written in completely non-mathematical language. The book systemati-cally covers the physical, psycho-physical and psychological aspects of color, discussing the effects ofthese factors on the observer. Starting with the physics of color, the book goes on to include atreatment of the properties of the eye, then considers the effects due to the observer himself. Thewhole is then discussed in relation to the various fields in which color plays an important part.Only a knowledge of first principles of physics and psychology is needed for the study of Intro-duction to Color.Ready in May Approximately 336 pages Probable price, $6.00

FOUNDATIONS OF PSYCHOLOGYEdited by Edwin G. Boring, Professor of Psychology, Harvard University; Herbert S. Langfeld,Stuart Professor of Psychology, Emeritus, Princeton University; and Harry P. Weld, Professor ofPsychology, Emeritus, Cornell University, Visiting Professor of Psychology, Rice Institute.

Each of the 25 chapters in this new book has been written by a recognized authority on thesubject covered. As a result of expert writing, checking and editing, the book offers a unified,concise, smoothly-flowing exposition of fundamentals. Beginning with response as basic, the treat-ment passes to emotion, learning and thought. It concludes with chapters on individual differences,personality, personal adjustment, vocational selection, attitudes and opinion, and social relations.Ready in May 613 pages (double-column) Probable price, $4.00

POPULAR GEMOLOGYby Richard M. Pearl, Assistant Professor of Geology, Colorado College.

A readable survey of the field, using the method of classification explained in Dana's Systemof Mineralogy, seventh edition. Popular Gemology is the only book with separate chapters covering(1) fluorescence and (2) quartz and other silica gems. Contents: The Lure of Gems; RecognizingGems; Faceted Gems; Cabochon and Carved Gems; Gems of the Silica Group; Gems with a Genealogy;Man-Made Gems; Luminescent Gems; Selected Reading.Ready in May 312 pages $4.00

ANIMAL BREEDINGFourth Edition

by Laurence M. Winters, Professor of Animal Husbandry, in charge of Research in Animal Breeding,University of Minnesota.

Presents the subject from the biological viewpoint, tracing the developmental history of variousbreeds, and discussing the principles of heredity and the physiology of the reproductive organs.Revisions in this edition are many. The discussion of community breeding has been incorporated intoother sections. Material on inbreeding, crossbreeding and artificial insemination has been greatlyexpanded. The treatment of selection now comprises two chapters covering selection and the ef-fectiveness of selection. The final chapter has been completely rewritten; it now discusses buildingsuperior germ plasm, giving full attention to the progress made in recent years.April 1948 402 pages $4.50

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T. STERRY HUNT was an AmericanChemist, mineralogist, and geologist.

In 1845 he became assistant to the elderSilliman at Yale College; later was chem-ist and mineralogist to the Canadian Geo-logical Survey, Professor of Chemistry atLaval and McGill Universities, and Pro-fessor of Geology at M. I. T.

In 1859 he invented the green ink withwhich greenbacks are printed.

He was President of the Royal Society ofCanada in 1884, a member of the NationalAcademy of Sciences, member and Presidentof the American Association for the Ad-vancement of Science, and member of theAmerican Institute of Mining Engineers.He was President of the American Chemi-cal Society in 1879 and again in 1888.

He died in 1892.

This is the eighteenth of a series of briefbiographies of eminent chemists sponsoredbyThe Coleman & Bell Co., ManufacturingChemists, Norwood, Ohio, U.S.A.

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PHYSICO CHEMICAL EXPERIMENTSBy Robert Livingston

Professor of Physical ChemistryUniversity of Minnesota

In the revised edition of this laboratory manual the author has clarified certainexplanations, modified the technique of a few experiments to simplify the stu-dent's laboratory work, and added new experiments-one in which heats of com-bustion are measured by means of a commercial bomb calorimeter and a quanti-tative study in the field of colloid chemistry, which requires only simple apparatus.The section on Measurements, Errors and Computations, has been revised,although the fundamental outline has not been changed. A brief discussion ofreport writing has been added as a new feature. Second Edition.

To be published this spring. $3.00 (probable)

FOOD PRODUCTSBy Henry C. Sherman

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Maintaining the general scope and arrangement of the first editions of this well-known text, the new fburth edition has been brought completely up to date, andrevised in the light of new developments in the field. Each chapter has four mainparts: (1) ant account of food production, its preparation for the market, andwhere necessary, a brief sketch of marketing and storage methods; (2) questionsof sanitation, inspection, and standards of purity or of conventional marketgrade; (3) the general composition, mineral content, and vitamin values; (4)special characteristics, digestibility, nutritive value and place in the diet. FourthEdition.

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RADIO FUNDAMENTALSBy Arthur L. Albert. Oregon State College. Ready in May

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FUNDAMENTALS OF PHYSICAL SCIENCE. New second editionBy Konrad B. Krauskopf, Stanford University. Ready in MayAs before, the author presents physical science as a unified field of knowledge, with emphasis on basiclaws and principles rather than details of applied science. The material has been brought up to date.The chapter on the atomic nucleus has been entirely rewritten and other important changes have beenmade.

FUNDAMENTAL PRINCIPLES OF BACTERIOLOGY. New third editionBy A. J. Salle, University of California at Los Angeles. 725 pages, $6.00

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Laboratory Manual on Fundamental Principles of Bacteriology. New third edition| By A. J. Salle. 200 pages, $225

HEREDITY. New fourth editionBy A. Franklin Shull, University of Michigan. McGraw-Hill Publications in the Zoological Sciences.322 pages, $4.00

* This well-known text has been extensively rewritten in terms of the important new developments ingenetics, and includes a discussion of the work of Beadle and others on the biochemical effects ofgene mutation.. As in earlier editions, the text deals with the principles of biological inheritance, withparticular emphasis on human heredity.

CHEMICAL CALCULATIONS. New fifth editionBy J. S. Long, formerly of Lehigh University, and H. V. Anderson, Lehigh University. InternationalChemical Series. 410 pages, $3.75

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Here, from the researcher's point of view, is thefascinating story of modern industrial research.Here are the techniques that led to the develop-ment of high-octane gasoline; celluloid, thefirst synthetic plastic; modem refrigerants;synthetic rubber, and a host of other importantachievements.

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SCIENCE will present two his-torical articles. One will cover thesignificant scientific and technicalbooks during the AAAS century,1848-1948. The second article willpresent the growth and develop-ment of scientific journals duringthe same period. A third featurewill be an informational listing ofoverseas publishers of scientificbooks.

THE SCIENTIFIC MONTHLYbook issue will feature the organi-zation and management of scientificinformation. Articles are beingprepared by leading scientists andstaff members of libraries specializ-ing in scientific publications. Twocontributions are planned from theLibrary of Congress's staff.

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Personnel Placement

POSITIONS WANTED

Biochemist: Ph.D., desires position in research or teaching withresearch opportunities. Twenty years of experience research inuniversity medical school on protein chemistry, immunochemistry,bacterial chemistry, etc., also considerable teaching experiencechemistry and biochemistry in university and medical school.Numerous publications, middle age, married. Box 267A,SCIENCE.

Biologist: Man, Ph.D. zoology, publications. Seventeen yearsexperience, invertebrate, general zoology, parasitology. Minors:botany, bacteriology. East preferred, higher ranks, $4000. Box266A, SCIENCE.

Biologist: M.S., research publications, desires position teachingbotany, zoology, etc. 5 years experience. Write Box 273A,SCIENCE.

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Chemist: Recent Ph.D. (Major: physical and colloid chemistry),experience in biochemical post-graduate research (protein andenzyme chemistry); desires research -position. Speaking English,French, Italian, German and Dutch. Nationality, Dutch. 34Years old, married. Excellent references. Communicate airmail,Mr. Luddo Nanninga, Gabriel Metsustraat 6, Amsterdam, Holland.

Immunologist: Ph.D.; several years, research assistant universitymedical school; three years on faculty, department of bacteriology,middle western university; for further information, please writeBurneice Larson, Director, Medical Bureau, Palmolive Building,Chicago 1 1.

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Physicist: Ph.D., educated at M.I.T., and abroad, has charge ofinstrument development program of large optical manufacturing.concern; given papers and lectures at AAAS, Yale, M.I.T., ShellOil Laboratories, Mellon Institute, Microchemical Society, JohnsHopkins, U. of Texas, Marine Biological Laboratories, etc.; co-author of volume on Instrumentation; widely travelled: acquaintedwith scientific personnel and problems in physics, chemistry, geol-ogy, biology, medical sciences, metallurgy, ceramics, textiles,food technology, drugs, paper, plastics, and tool engineering.Interested in directorship of industrial laboratory, leading positionin educational field, or administrative function with broad pos-sibilities. Box 275A, SCIENCE.

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POSITIONS OPEN

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Personnel PlacementPOSITIONS OPEN

Anatomists: Attractive positions open in a progressive state uni-versity school of dentistry, excellent salaries and opportunities foradvancement and research, rank and salary open. Young men withPh.D. degrees preferred, give full details. Can interview at theWisconsin meetings. Box 251A. SCIENCE.

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THE UNIVERSITY OF MANITOBAThe University of Manitoba invites applications for the followingpositions in the Department of Physics:1. One professorship (research), with limited teaching duties infield of specialization in senior undergraduate courses. Salaryrange $4100 to $4700.2. Several appointments as associate professor (salary range $3700to $4200), assistant professor (salary range $2700 to $3700) andlecturers (salary range up to $2750).Applications should be sent to the Dean of Arts and Science, Uni-versity of Manitoba, Winnipeg, Manitoba, and should include state-ment of the applicant's academic qualifications and his teaching andresearch experience, and three letters of reference of recent date.

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The Market Place The Market PlaceBOOKS SUPPLIES AND EQUIPMENT

All Amino Acids (natural and synthetic, rare sugars, biochemicalWANTED TO PURCHASE SCIENTIFIC BOOKS products and reagents, new pharmaceuticals in stock. Write for

AND PERIODICALS complete price list. BIOS LABORATORIES, 607 West 43rdEntire libraries, and smaller collections; sets and runs; Street, New York 18.

foreign and domestic.WALTER J. JOHNSON, Amino Acid and protein analysis by microbiologic methods. Re-125 East 23rd Street, New York 10. search problems on contract basis. SHANKMAN LABORA-

TORIES, 2023 South Santa Fe Ave., Los Angeles 21, California.Journals Periodicals, Learned and scientific serials bought andsold. (omplete or part sets, back volumes. J. S. CANNER &COMPANY, INC., 909 Boylston Street, Boston 15, Massachu-5etts. Index of Refraction Liquids for Immersion Meth-Send us your Lists of ods of Microscopy. Stable, non-volatile, certified

SCIENTIFIC BOOKS AND PERIODICALS liquids 1.400 to 1.700; high index liquids, abovewhich you have for sale. 1.80, in preparation. Write for data 847-ND.

Complete libraries; sets and runs; and single titles are wanted.Also please send us your want lists. R. P. CARGILLE,

STECHERT-HAFNER, INC., 31 Eat 10th Street, New York 3. 118 Liberty St., New York 6, N. Y.

The SPRING BOOK ISSUE of Pre-Mized Microbiological Assay Me (One complete mie):SCIENCE assay standards: pure amino acids (analysed): microbiologicalassays. H. M. CHEMICAL COMPANY, LTD., 144 North

will appear May 14, 1948. Hayworth Avenue, Los Angeles 36, CalforniaUse this special opportunity to advertise your wantsor books and journal sets that you may have for sale. Wanted to buy or rent: One Leitz Ultropak Illuminator without

microscope, with objectives giving magnifications 60-100. Box10# per word ($2.50 minimum) 271, SCIENCE.

Send to: SCIENCE, 1515 Massachusetts Avenue, N.W. PROFESSIONAL SERVICESWashington 5, D. C.

Electronic Engineer: Design and construction of special equipmentfor power, control and measurement. LIONEL LIPSCH ULTZ,273 South Clinton Street, East Orange, New Jersey.

BOOKS LARGE STOCK OFSCIENTIFIC AND TECHNICAL Second AnnualWORKS ALWAYS AVAILABLE InternationalI LONDON : H. K. LEWIS & CO., LTD. lll htga y-n iec Slo

Cables: Publicavit : Westcent: London : England. Sponsored byLANGUAGES THE SCIENTIFIC MONTHLY-

LINGUAPHONE MAKES LANGUAGES EASYAt home learn to speak S ish Portugnese, Italian, French, ITHSONIAN INSTITUTIONGerman, Russian, by quick easy Linguaphone ConversationllMethod. Save time, work, money. Linaphone CorrespondenceCourses are available to Veterans under GI BILL OF RIGHTS. Accepted entries will be shown fromSend for free book. State if GI. LINGUAPHONE INSTI- September 1 to 21, inclusive, in the Nat-

TUTE'4 RCA ldg..ewYor 0.'N. Y.ural History Building, U. S. NationalIF YOU ARE CHANGING YOUR Museum, Washington, D. C., and subse-

ADDRESS, please let.us know, if possi- quently in museums throughout theble, four weeks in advance, giving old as country.well as new address, and adding zone For information and entry blanks,number to meet postal requirements. If write toyou are unable to notify us, so as to affectsucceeding issues, kindly leave instruc- The Editortions and postage with your postmaster The Scientific Monthlyfor forwarding your copy. Second classmatter requires postage when remailed to 1515 Massachusetts Ave., N. W.a different address. Washington 5, D. C.

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1515 Massachusetts Avenue, N. W. NO ENTRY FEEWashington 5, D. C.

21

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With the TRACERLAB Su-3 0onitorthe SU3 RTOR

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Sh~own above on a background of tlle aberration curves witllM R~~wich American Optical Comnpany-scientists predict lens

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