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How Balcote Surfaces

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11 October 1946 9

SCIENCE-ADVERTISEMENTS

o4aued1 66eme 7gez4Arnow's PHYSIOLOGICAL ANDPATHOLOGICAL CHEMISTRY-2ndEdition. 574 pages, 142 illustrations.$3.75

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Whiteford and Coffin's ESSENTIALSOF COLLEGE CHEMISTRY-2nd Edi-tion. 534 pages, 32 illustrations. $3.50

Myers' LABORATORY DIRECTIONSIN BIOCHEMISTRY-288 pages, 17illustrations. $3.50

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SCIENCE-ADVERTISEMENTS

It (d4

ESSENTIALS OF PHYSIOLOGICAL CHEMISTRYBy ARTHUR K. ANDERSON, Professor of Physiological Chemistry, The Pennsylvania StateCollege.

Revised and expanded, this excellent elementary textbook gives a clear and concise account of themain aspects of biochemistry. It provides the material necessary to meet the strictest require-ments for short courses for students of chemistry, bacteriology, home economics, dietetics, nutri-tion, agriculture, and premedicine. The new edition is completely up to date and contains muchnew material. There is a comprehensive set of review questions at the end of each chapter.Ready in November.

Third Edition; Approximately 397 pages; 6 by 91/4; Probable price $3.50

LABORATORY EXPERIMENTS IN PHYSIOLOGICALCHEMISTRY

By ARTHuR K. ANDERSON.A companion piece to Professor Anderson 's " Essentials of Physiological Chemistry," this labo-ratory manual is now presented in a revised printing. Experiments are carefully selectedand directions are clear and precise. Blank right-hand pages permit taking notes on experi-ments. Suggested lists of reagents, apparatus, and chemicals in approximate amounts for aclass of twenty-five students are included. Ready in November.

Revised First Edition; Approximately 238 pages; 5% by 8%; Probable price $2.00

FOREST SOILSBy HAOLD J. LuTZ, Professor of Forestry, Yale University, and ROBERT F. CHANDLER,JR., Professor of Forest Soils, Cornell University.

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PHOTOGRAPHY BY INFRAREDBY WALTER CLARK, Assistant to the Vice-President in charge of research, Eastman KodakCompany.

Extensively revised, this popular book now includes the many recent developments and applica-tions in this field. As in the previous edition, it deals in equal detail with the general practiceof infrared photography as carried on today, the materials available, and the application of itsmethods to practically every field wherein it has been-used. The first part of the volume consti-tutes an introduction to the subject, covering the history, general practice, materials and lightsources; the remainder of the book deals with applications. Ready in October.

Second Edition; Approximately 460 pages; 6 by 91/4; Probable price $6.00

ELECTRONIC THEORY OF ACIDS AND BASESBy W. F. LUDER, Associate Professor of Chemistry, and SAVERIO ZUXPANTI, AssociateProfessor of Chemistry; both at Northeastern University.

This new book offers a systematic presentation of the relationship of the electronic theory ofacids and bases to chemistry as a whole; it points out the way in which this theory can performa useful function in chemistry. The text covers the historical background, atomic orbitals andvalence, electrophilic and electrodotic reagents, acidic and basic radicals, catalysis and othertopics. Piuilished October 7th.

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SCIENCE-ADVERTISEMENTS

From 30 Years' Research Comes This Important Workon RADIANT ENERGY'S USEFULNESS to Mankind

APPLICATION OFGERMICIDAL,ERYTHEMAL

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byMATTHEW LUCKIESH,

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INTRODUCTORY QUANTUM MECHANICSBy Vladimir Rojansky, Ph.D., Union College

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INTRODUCTION TO THE THEORY OF RELATIVITYBy Peter G. Bergmann, Ph.D., Columbia University

* Here is an up-to-date presentation of the theory of relativity by aphysicist who worked with Dr. Einstein. With this the physicsstudent can approach the subject by the familiar road of physicaltheory instead of through pure mathematics.287 pages 6" x 9" College List, $4.50

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CatalogNOW AVAILABLE UPON REQUEST

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Bacto-AgarBacto-Agar is a purified Agar prepared from

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SCIENCE-ADVERTISEMENTS

Greater Accuracy in Absolute UnitsHOEPPLER

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11 October 1946 15

Personnel Placment

POSITIONS OPEN

Biochemist-Assistant Professorship In midwest medicalschool; doctorate required; experienced teacher wanted;publications. Box 589, SCIENCE.

For Discerning Placement Write Tom COFFER, EmploymentCounsellor to the Scientist Exclusively. 20 W. Jackson,Chicago 4.

Experienced technician In histology. Immediate and perma-nent employment. Write to DR. L. F. BERLANGER, Dept. ofHistology, University of Ottawa, Ottawa, Ontario, Canada.

Opportunities Available-(a) Instructor or assistant profes-sor, department of botany, agricultural college; should beable to teach botany and one or two advanced courses suchas ecology, range and pasture botany or plant pathology;Ph.D. preferred; person with M.S. degree eligible. (b) As-sociate professor of bacteriology, fairly young man withPh.D. in bacteriology preferred; duties involve assistingwith teaching of course in general bacteriology and, also.courses in immunology, serology, food and sanitary bac-teriology; New England. (c) Instructor in organic chem-istry, liberal arts college; South. (d) Physiologist andpharmacologist to head department in university school ofmedicine; 1Ph.D. required; preference to one with medicaldegree; $3,500-$5,000. (e) Young physicist or astronomercapable of taking observations of the electrical and magneticactivities producing the Aurora and making technical calcu-lations of the results; service requires joining expedition tothe auroral zone in Greenland for approximately three monthsof the winter. (f) Instructors for freshman biology andbotany; master's degree or better required; state agricul-tural college; Southwest. (g) Biochemist well versed inmodern biochemistry and prepared to supervise chemistrydepartment; must be capable of carrying on considerableresearch; large hospital; New York City. (h) Young phy-sician with moderate amount of clinical experience to joinstaff of large pharmaceutical company; duties Involve prepa-ration of medical texts on use of medical products; East.S10-2 The Medical Bureau (BURNEICE LARSON, Director),Palmolive Building, Chicago 11.

Personnel PlacementPOSITIONS OPEN

Physicians, Laboratory and X-Ray Technicians, Bacteriolo-gists, Pharmacists, Physical Therapists let us help yousecure a position. Our service, established 1896, Is Nation-wide. Write us today. All information confidential.AZNOZ'S-WOODWAaD BUREAU, 30 North Michigan, Chicago 2.

Bacteriologist: D.V.M.; Ph.D. in immunological chemistryand pathology; 16 years laboratory practice and teaching;hospital, public health, toxicology; veteran. Box 607,SCIENCE.

Botanist, Ph.D., major physiology, minors morphology andecology, desires research or research and teaching position.Box 601, SCIENCE.

Opportunities Wanted-Biochemist is available: twelve years'experience in research; five years In laboratory of plantmanufacturing soap and edible fats; duties in army con-sisted of research in problems in applied physiology (aero-embolism and various other strictly practical aspects ofphysiology at altitude, dehydration, etc.); in early forties;particularly interested in laboratory methods and apparatusin chemical or biochemical research; for further information,please write BURNEIcE LARSON, Director, Medical BureauPalmolive Building, Chicago 11.

The California Medical Bureau, Agency for scientific and laypersonnel in medicine, biology, chemistry, physics, and alliedsciences, supplies teachers, research workers, laboratorydieners, skilled office help. Prompt service. Registrationfree. Your patronage respectfully solicited. THE CALI-FORNIA MEDICAL BUREAU, Agency, Arcade Medical Center, 69Colorado Street, Pasadena 1, California.

Zoologist: Vassar A.B., hematologist. Eighteen months ofpharmacological research at leading eastern industrial plant.Prefer research position in medical school or hospital. Box608, SCIENCE.

Organic chemist, woman, M.A. Columbia. Three years ex-perience synthetic pharmaceuticals research. French, Ger-man, Italian. Northern Newv Jersey. Box 614, SCIENCE.

Physicist, 29, A.B., M.S., desires position in New York-NewEngland area. Experienced in biological applications ofultracentrifuge and electron microscope. Box 615, SCIENCE.

Biochemist; Ph.D. (Minor: organic chemistry), at presenthead of university department of biochemistry, desires re-search position. Main fields of research: Nutrition (vita-mins) and Metabolism. Seventy publications. Minimumsalary $8,000. Box 617, SCIENCE.

TRANSLATIONSForeign technical and scientific articles translated at reason-able rates. BoX 611, SCIENCE.

CHARGES FOR CLASSIFIED ADVERTISINGRegular setting 10¢ a word. Minimum charge $2.00for each Insertion. A box number counts as 8 wordsof the advertisement (e.g. 20 words plus box numberequals 28 words). Make checks payable to the A.A.A.S.All insertions must be accompanied by correct remit-tance and sent to the Adv. Dept., A.A.A.S. Pleaseaddresse replies as follows: Box number, SCIENCE,1515 Mass. Ave., N. W., Wash. 5, D. C. EXCELLENT RESEARCH

OPPORTUNITYPhysicist or Biophysicist

For basic research on photosynthesis and otherbiological effects of light.

QualificationsTraining equivalent to that represented by gradu-ation from a recognized college and a Ph.D. inphysics or biophysics or three years professionalexperience in this field and other necessary quali-fications to meet the requirements of this P-4 CivilService position.

SalaryThe initial salary is $4,902.00, less 5 percent deduc-tion for retirement according to governmentalregulations.Full particulars and application forms may be ob-tained from the Division of Radiation and Organ-isms, Smithsonian Institution, Washington 25, D. C.

POSITIONS WANTED

PERSONNEL PLACEMENT113th Meeting AAAS

Boston, 26-31 December

Following the plan established for the 112thAAAS Meeting, St. Louis, 1946, SCIENCE willhave additional space devoted to PersonnelPlacement in the issues of December 6, 13,and 21, 1946.

While the AAAS does not maintain a place-ment service, it does provide the opportunityto arrange employment interview appointmentsat the meetings through announcements inthese columns. At the Boston Meetings specialfacilities for conducting interviews are beingprovided.

The October 18 issue of SCIENCE will have com-plete details of these services on this page.

The Market Place Now! Get COPIES ofWanted to purchase-Scientific Periodicals, sets and runs, n in luff!Foreign-Domestic. Entire libraries and smaller collections.WALTPOR J. JOHNSON, 125 East 23rd Street, New York 10.Journals, Periodicals, sets and runs. Also whole collectionspurchased for cash. J. S. CANNER & COMPANY, 909 Boylston ... Right in your own office! New low- cost,Street. Boston 15. massahsnee-ttsS E C O N D -H A N D B O O K S error- proof method records data permanently

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IIMEDICHROMESII*Series MB BACTERIOLOGY

A series of approximately 200 2 x 2" (35 mm.) Kodachrome lanternslides made with the cooperation of DR. GREGORY SHWARTZMAN,Department of Bacteriology, Mt. Sinai Hospital, New York City. Seriesconsists of photomicrographs of the organisms, photographs of colonies,cultures and various bacteriological phenomena. B 1 a phenomonPrices

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