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Requires no previous training-

AN INTRODUCTIONTO COLOR

by Ralph M. Evans, in charge of Color Quality,Color Control Department, Eastman KodakCompany.

A fundamental study, written in non-mathe-matical terms. The book systematically coversthe physical, psychophysical and psychologicalaspects of color. Starting with the physics ofcolor, the treatment includes a section on theproperties of the eye, then considers the effectsdue to the observer himself. The whole is thencovered in relation to the fields in which colorplays an important part. Fifteen full-page colorplates are included in a total of about 300illustrations.

June 1948 340 pages

Gives the farmer's point of view-

FARM SOILSFourth Edition

by Edmund L. Worthen, Professor Emeritus ofSoil Technology, Cornell University.

Written from a practical point of view, FarmSoils includes: directions for managing soils infarming; wide coverage of such operations asfertilizing, liming, manuring, draining, irri-gating and tilling; practical methods of soilconservation; complete details of managing soilsof gardens, lawns and orchards. This editioncontains a new chapter on erosion and its con-trol. The most recent information is includedon the best types of fertilizers and theirapplication.

Ready in August Approx. 511 pagesProbable price, $3.60

For classroom and laboratory-

ANIMAL BREEDINGFourth Edition

by Laurence M. Winters, Professor of AnimalHusbandry, in charge of Research in AnimalBreeding, University of Minnesota.

The subject is presented from the biologicalviewpoint, tracing the developmental history ofvarious breeds, discussing the principles ofheredity and the physiology of the reproductiveorgans. The material on inbreeding, crossbreed-ing and artificial insemination has been ex-

panded in this edition. The treatment of se-

lection now comprises two separate chapters.Throughout the book, full attention is given tothe progrem made in recent years.

$6.00 April 1948 404 pages $4.50

Readable exposition of clear thinking-

ATOMIC ENERGYby Karl K. Darrow, Physicist, Bell TelephoneCompany, and Secretary, American PhysicalSociety.

This is a book of four lectures delivered in1947 by Dr. Darrow as the Norman Wait HarrisLecturer at Northwestern University. Well-known aspects of the atom come first, followedby a discussion of mass and isotopes. Then, atalk on nuclear theory leads the reader to anunderstanding of atomic fission. "The lec-tures," says one reviewer, "are typical Darrowproducts-semi-popular scientific exposition witha clarity and charm that continue the Darrowtradition at its best."

Ready in June Approx. 84 pagesProbable price, $2.00

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NEW EDITIONS*

The Machineryof the Body

By ANTON J. CARLSON, M.D. and VICTOR JOHNSON, M.D.REVISED 1948 EDITION

New material on: Transfusion of blood, the "wonder" drugs, vitamins,pernicious anemia, emotional disorders, cancer, radio-active elements inmedicine, pugs several new illustrations. $4.50

AnimalsWithout Backbones

By RALPH BUCHSBAUM

An Introduction to the InvertebratesREVISED 1948 EDITION

* Completely up to date* 537 magnificent photographs-more than 150 of them new* Legends for photographs rewritten-and, as before, form an integral partof the text

* 316 drawings and diagrams-many not included previously* Gravure illustrations numbered for easy reference $5.°°

* The revised editions of The Machinery of the Body and Animals Without Backbones will be ready around July 1.Order your examination copy (see coupon on next page) and plan now to use these new editions in your fall classes.

THE UNIVERSITY OF CHICAGO PRESS

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FOR FALL CLASSES!NEW!

MANUAL FOR LABORATORY WORK IN

Mammalian

Physiology 'tBy FRED D'AMOUR and FRANK R. BLOOD

The Manual includes a group of 50 experi-ments in which the rat is used exclusively. Itprovides ample material for work in physiologyfor premedical students and physiology majors.Two hundred and fifteen large and amazingly

clear photographs illustrate, step by step, theinstructions for each experiment.Equipment required is all low cost-most of

it standard laboratory apparatus. Rats are

cheaper, hardier, and more easily obtainablethan other laboratory animals.The authors follow the customary sequence

of experiments: blood, heart and circulation,respiration, digestion and metabolism, excre-tion, nervous system, endocrine system, andantibody formation. This arrangement is flexi-ble enough, however, to allow adaptation toindividual course needs.Now available. $2.75

Two other standard texts in Biological ScienceFor vertebrate zoology

MAN AND THE VERTEBRATESBy ALFRED SHERWOOD ROMER. This textpresents a clear and readable story of the evo-lution of the body of man through four hundredmillion years. 552 pp., hundreds of illustrations.

$4.50For elementary botany

THE STORY OF THE PLANT KINGDOMBy MERLE C. COULTER. Phylogenetic se-quence holds a more prominent place in this bookthan in most others-not in the form of dogma,but as an attractive basis for organization.284 pp., 119 illustrations. $2.75

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Write direct for "Modern pH andChlorine Control". 96 pages ofthe latest methods and equipmentin 34 basic industries. See yourdealer for equipment.

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NEW GEIGER COUNTER

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ai instrumentsinclude sipeleP charge. The new Model D31 counter can be provided with or withoutscalers, asm1 proportional socket, and incorporates provision for a mounting ring on the micacountertsh n tic \ end when used with upright-type sample holders.I nstru Model D31 counter has a plateau from 1100 to 1300 volts, with

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PRACTICAL ASTRONOMY.New 2nd edition

By J. J. NASSAU, Case Institute of Technology.315 pages, $5.00

Designed especially for students of practical or geodeticastronomy, this well-known text has been revised to cover

a broader point of view than the earlier edition, and topresent new material, illustrations, and diagrams. Themeridian angle and azimuth angle are defined and used,simplifying the exposition. The concept of sidereal timeis presented, but is not employed for ordinary de-terminations of time, latitude, and azimuth.

NUMBER THEORY AND ITS HISTORYBy OYSTEIN OnE, Yale University. Ready insummer

A readable account of some of the main problems, meth-ods, and principles of the theory of numbers, togetherwith the history of the subject, and a considerable num-

ber of portraits and illustrations.ber of portraits and illustrations. Although the authorhas not sacrificed mathematical rigor in the interest ofthe "cultural" student, this book is less technical mathe-matically than the usual text in the field.

HEAT CONDUCTION. With Engineeringand Geological Applications

By L. R. INGERSOLL, University of Wisconsin; 0. J.ZOBEL, Bell Telpehone Laboratories; and A. C.INGERSoLL, University of Wisconsin. InternationalSeries in Pure and Applied Physics. 295 pages,

$4.00

Presents the theory of heat conduction with discussionof many practical applications, including such topics as

ground heat-pump sources, geysers, periodic flow, electricwelding, post-glacial time calculations, canning anddrying operations, etc.

SEQUENCE IN LAYERED ROCKS. A Studyof Features and Structures Useful for De-termining Top and Bottom or Order of Suc-cession in Bedded and Tabular Rock Bodies

By ROBERT N. SHROCe, Massachusetts Institute ofTechnology. Ready in summer

Intended for advanced geology students, this book repre-sents, to some extent, a field manual of structural ge-ology. It contains extensive descriptions and illustra-tions of all the common, and many of the uncommon,features in rocks of all kinds.

PHARMACOLOGY AND THERAPEUTICSIN NURSING

By MARION S. DOOLEY, M.D., Syracuse University;and JOSEPHINE RAPPAPORT, R.N., Veterans Adminis-tration Hospital, Alexandria, Louisiana. 444 pages,$3.75

A concise text providing the essentials of drug therapy.Nursing care is stressed throughout and the material ispresented in such a way as to facilitate the correlationof pharmacology and therapeutics with both preclinicaland clinical courses.

ELEMENTS OF THE THEORY OFEQUATIONS

By J. V. UsPENSKY, late of Stanford University.Ready in summer

An exceptionally thorough treatment of the subject, withfull and explicit development of material. Emphasisthroughout is on both theory and numerical methods.An original and efficient method is given for separatingreal roots. Determinants are introduced, not as usual byformal definition, but by their characteristic properties.

Send for copies on approval

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

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Special Pre-Publication Offer

to Readers of Science

THE method of rhythmical designpresented by Joseph Schillinger

links together on a mathematical basis thearts of music, literature and the space arts.In his method, Schillinger reveals the funda-mental mathematical laws of structure un-derlying plant and animal life, and the ap-plications thereof in the art forms of de-veloped cultures of the past. In my opinionhis achievement is a genuine and valuablecontribution to the study of esthetics and toart education. Because the laws which heformulates are mathematically fundamen-tal, Schillinger's method is applicable notonly in the analysis of existing works of artand of musical compositions, but offers adefinite and workable procedure for archi-tects, painters, composers, sculptors, anddesigners in the industrial fields."While in no way interfering with or

limiting the imagination and feeling of theartist, it replaces the 'trial and error'method with one that is logical, easy of ap-plication, and as precise and sound as thestructure of nature itself. "-Prof. C. J.Martin, Teachers College, Columbia Uni-versity"ESTHETIC realities, states the original

and intriguing mathematician, JosephSchillinger, are in no way discontinuouswith physical realities. Schillinger pos-sesses for his affirmations and propheciesa base in technology and artistic experience.Bertrand Russell announces the gospel andSchillinger designs and constructs the ma-chinery of its applications.''-Dr. HoraceM. Kallen, Art and Freedom

LIMITED EDITION 0

Publication date isJULY 1948

If you send in your orderbefore publication, you canget your copy for

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THE

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"THE AUTHOR'S goal is, in his own

words, 'to disclose the mechanism of creator-ship as it manifests itself in nature and inthe arts.' We are convinced he has achievedthat goal. All the arts, like Architecture,must be built. And toward their building-perhaps as a guide in their planning andcertainly as a corrective of their creator'smortal errors of execution, a knowledge ofTHE MATHEMATICAL BASIS OF THEARTS is of profound importance. "

-Rockwell Kent

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THE CARWORTH FARMSQUARTERLY LETTER

This 4 page digest is mailed to people in thefield of scientific research. It is especiallyhelpful to those whose activities are centeredaround the use of laboratory animals.

Significant papers not in general circula-tion, important excerpts from specializedscientific publications, and new materialare grouped and edited for study and ref-erence.

We have received many appreciative com-ments on the Letter's usefulness. The Car-worth Farms Quarterly Letter will be sentwithout charge on request.

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ANIMAL COLOUR CHANGESAND THEIR NEUROHUMOURS

By George Howard ParkerEmeritus Professor of Zoology, Harvard University

We are pleased to announce the publication of this important survey of investigationsfrom 1910-1943 on animal colour changes. Dr. Parker's first chapter is a general intro-duction to the subject, and deals in orderly fashion with the several kinds of chromato-phores. Subsequently he discusses colour changes in cephalopods, crustaceans, vertebrates(four chapters), the development and growth of vertebrate chromatophores, and theirspecial activities. Fully ilustrated. Cambridge University Press. $6.50

INORGANIC PROCESS INDUSTRIESBy Kenneth A. Kobe

Professor of Chemical Engineering, University of Texas

This book presents the theory of inorganic processes and shows how this theory is appliedin basic procedures in industry and in the design and operation of equipment. It providesan excellent discussion of fundamental sciences and technology, equipment, processingmethods, flow sheets, etc. The industrial aspects of marketing and statistics, and therelative economics of different processing methods are fully dealt with. To be publishedthis spring. $5.75 (probable)

PHYSICO CHEMICAL EXPERIMENTSRevised Edition

By Robert LivingstonProfessor of Physical Chemistry, University of Minnesota

In the revised edition of this laboratory manual the author has clarified certain explana-tions, modified the technique of a few experiments to simplify the student's laboratorywork, and added new experiments-one in which heats of combustion are measured bymeans of a commercial bomb calorimeter, and a quantitative study in the field of colloidchemistry, which requires only simple apparatus. To be published this spring.$3.00 (probable)

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Personnel Placement

POSITIONS WANTED

Chemist: Ph.D. (Major, organic chemistry; minor, microbiology).:several years teaching experience; four years research fellow inbiochemistry and pathology; eight years director of research inlarge industrial company; for further information, please writeBurneice Larson, Director, Medical Bureau, Palmolive Building,Chicago 11.

Geologist: Ph.D. Ten years academic, commercial, governmentalexperience. Interested teaching with publication-research oppor-tunities. Available June, September. Box 328A, SCIENCE.

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Scientific Writing translating, abstracting; medical, biological ex-perience; knowledge scientific French and German; Philadelphiaarea or by mail. Box 322A, SCIENCE.

POSITIONS OPEN

LIBRARIANwith chemical and biological background. Some administrativeexperience preferred for technical library for pharasaceutical and,chemical manufacturer near Philadelphia.

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Botanist: Ph.D., to teach plant pathology and plant physiology.at a California state college. Instructor or assistant professor de-pending upon experience. Box 323A, SCIENCE.

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Positions Open: (a) Bacteriologist to take charge of new bac-teriology department in connection with research for new drugproducts, pharmacologist to head research department and organicchemist to do research in synthetic organic chemistry department;large biological manufacturing company having expansion program;salary range $4000-$5000. (b) Endocrinologist; Ph.D. required.should be experienced in various assay procedures for evaluation of.agents having hormonal activity; duties administrative including-research. (c) Young scientist, well trained in physical chemistryto join research staff of large industrial company; at present labora-tory relatively small but company has expansion program and is-remodeling building to be used strictly for research laboratories;-Chicago area. (d) Bacteriologist; duties include research on newproblem; meticulous worker with precise skills required; must be-qualified to supervise laboratories and direct research; opportunityfor academic appointment; university medical school; $4500-$5000.(e) Research librarian to join staff of medical research department,large industrial company; young woman with graduate training or.experience in chemistry, biochemistry or organic chemistry; dutiesconsist of literature research on the toxicity of various compoundsand products, assisting in planning toxicological experimental re-search; New York. (f) Bacteriologist and biochemist; Ph.D.'s-experienced in antibiotics; new antibiotic research laboratories;biological manufacturing company; Middle West. S5-4 MedicalBureau (Burneice Larson, Director), Palmolive Building,

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All Amino Acids (natural and synthetic, rare sugars, biochemicalproducts and reagents new iharmaCeUtical n stock. Write forcomplete price list. IBIOS LABORATORIES, 607 West 43rdStreet, New York 18.Amino Acid and protein analysis by microbiologic methods. Re-search problems on contract basis. SHANKMAN LABORA-TORIES, 2023 South Santa Fe Am., Los Angeles 21, California.

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