.SEPTEMBEa 21 1945 SOIENOE-AD1.ERTI.EMENTS 11

"In clarity, logic, method of presenta-tion and student appeal, no textbookhas more to ofter"-From a teacher

| ~~~~ByE. Wertheim, Ph.D., University of Arkansas 1

|TEXTBOOK OF ORGANIC CHEMISTRY 12nd Edition Published 1945 * 113 Illustrations * 867 Pages * $4.00

Teaching organic chemistry and teaching it well is helped considerably by the textbookchosen. In presenting this new edition, the author makes the initial learning easy bystressing the "humanizing" features of organic chemistry and its development. Thethumb-nail biographical sketches and portraits of important chemists, the chronologicaltables of historical events, the wide use of structural formulae, the charts of relationshipsfor study purposes, emphasis on industrial importance of organic chemistry, up-to-datereferences, colored plates of molecular models, and excellent practical problems-all arefeatures that have elicited the most appreciative comments of teachers and students usingthe book. The text meets the needs of beginning students-those who will major in chem-istry or specialize in organic chemistry and those enrolled in premedical or chemicalengineering courses.

WERTHEIMLABORATORY GUIDE FOR ORGANIC CHEMISTRY

2nd Edition (Reprinted 1945)24 Illustrations * 560 Pages * $2.00

This manual provides 169 varied experiments illustrating properties, methods of prepara-tion, reactions of organic compounds, and a section on "spot tests." Numerous appro-priate drawings are included and a timetable for each experiment is given as a guide tothe student.

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'SEPTiMBicp. 21, .945 SCIENCE-ADVERTISEMENTS 11

12 SCIENCE-ADVERTISEMENTS

9'~aaa REINHOLD Emu&CARBON DIOXIDESecond PrintingBy Elton L. Quinn, Professor of Chemistry, University of Utahand Charles L. Jones, Formerly Chief Engineer, American Dry Ice Corporation

Activity in the chemical field has rekindled the need for this out-of-print book. The many re-quests for it have resulted in its reprinting in a limited edition. It covers the history of the in-dustry, the occurrence of carbon dioxide in nature, by-product carbon dioxide from fermentation,the coke process, absorption and desorption, chemical properties and uses of carbon dioxide, manu-facture of solid carbon dioxide.294 Pages A.C.S. Monograph No, 72 Illustrated $7.50

BIOENERGETICS AND GROWTHWith Special Reference to the Efficiency Complex in Domestic AnimalsBy Samuel Brody, Chairman, Committee on Growth and Energy Metabolism, College of Agri-culture, University of Missouri

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THE CHEMISTRY OF ACETYLENEBy Julius A. Nieuwland, Late Professor of Organic Chemistry, University of Notre Dame;and Richard R. Vogt, Professor of Chemistry, University of Notre Dame

This volume serves thoroughly and systematically the entire literature relating to acetylenecompounds. Many years in preparation it carries on the unfinished work of the late FatherNieuwland, so vitally important to the early development od synthetic rubber in the UnitedStates. The book features valuable detailed discussions of: The Physical Properties, Prepara-tion and Purification of Acetylene; Metallo-Derivatives of Acetylene; Substitution of Non-Metal Atoms or Radicals for the Hydrogen of Acetylene; Addition of Non-Metallic Elementsand Compounds to Acetylene; Polymerization of Acetylene and Its Condensation with CarbonCompounds. Includes complete information on the chemistry, properties, and uses of Neoprene.216 Pages A.C.S. Monograph No. 99 Illustrated $4.00

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12 SCIENCE-ADVERTISEMENTS VOL. 102, No. 2647

SETM- 21 195CE C-D E TS M N S1

a5~~~~afd4 7ez(>~FOUNDATIONS OF BIOLOGYBy L. L. Woodruff

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HANDBOOK OF METEOROLOGYEdited by F. A. BERRY, JR., Comdr., USN, Staff Comair 7th Fleet; E. BoLLAY, Lieut. Comdr.,USNR, Aerological Staff, Postgraduate School, U. S. Naval Academy, and N. R. BEERS, Lieut.,USNR, Aerological Staff, Postgraduate School, U. S. Naval Academy. 1116 pages, 54 x 84,616 illustrations. $7.50

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Here is an up-to-date, well illustrated glossary containingclear-cut and accurate definitions of nearly 6,500 termsused in radio, television, industrial electronics, communi-cations, facsimile, sound recording, etc. This compilationof authoritative, readily understood definitions constitutes

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PULSED LINEAR NETWORKSBy ERNEST FRANK, Garden City Research Laboratories, Sperry Gyroscope Company, Inc. 266pages, 51 x 84, 183 illustrations and tables. $3.00

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SCIENCE-ADVERTISEMENTS VOL. 102, No. 264714

SETME 21 95SINEADETSMNS1

ESSENTIALS OF HUMAN EMBRYOLOGYBy GIDEON S. DODDS, Professor of Histology and Emnbryology, School of Medicine, WestVirginia University

Extensively revised, this third edition retains the plan and aims of earlier volumes but includesthe more recent advances in embryological knowledge. The chapter on early development iswholly new. Other sections which have been extensively rewritten are those dealing with thefetal membranes, the early mesoderm, the organs of respiration, the body cavities, the bloodvascular system, the lymphatics, the reproductive organs, and the organs of special senses. Newillustrations have also been added. November 1945.

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INTRODUCTION TO ORGANIC CHEMISTRYBy ALEXANDER Lowy, Late Professor of Organic Chemistry, University of Pittsburgh,BENJAMIN HARROW, Professor of Chemiltry, and PERCY APFELBAUM; Both at CityCollege of the City of New York.

This well-known text book has been thoroughly revised, with much new material added, includinga more extended discussion of the electronic concept of valence and the inclusion of such topicsas resonance, substitution in the benzene ring, alicyclic ring structures and high polymers. Thechapter on terpenes has been rewritten, and the list of references revised. October 1945.

Sixth Edition; Approximately 448 pages; 5% by 8%; Probable price $3.50

YOUTH, MARRIAGE AND PARENTHOODBY LEmo D. RoCKWOOD, Professor of Home Economics, and MARY FORD, Assistant Pro-fessor of Home Economics; Both at New York State College of Home Economics, CornellUniversity.

Essentially a presentation of research findings, this study of the attitudes of three hundred andsixty-four university juniors and seniors toward sex education, premarital sex behavior, marriage,parenthood and divorce stresses the relation between the attitudes expressed and selectedfactors in the students' own backgrounds. The findings of the present study are related topreviously made studies and to conditions as. they actually exist. September 1945.

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ELECTRON OPTICS AND THE ELECTRON MICROSCOPEBY V. K. ZWORYKIN, G. A. MORTON, E. G. RAmBERG, J. HILLmER, A. W. VANCE; All atBCA Laboratories,, Princeton, N. J.

This comprehensive book covers the electron microscope in all its phases. The material waschosen to fulfill a two-fold purpose. The first is to aid the present or prospective electronmicroscopist in understanding his instrument and using it to greatest advantage; the second,to present systematically the practical and theoretical knowledge which must form the basis forfurther progress in electron microscope design. September 1945.

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ORGANIC SYNTHESES. Volur1 W. E. BACHMANN, Editor-in-Chief

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SEPTEMBEP. 21, 1945 SCIENCE-ADVERTISEMENTS 15

SCIENCE-ADVERTISEMENTS VoL. 102, No. 2647

TWO IMPORTANT NEW BOOKS!

NETWORK ANALYSISand FEEDBACK AMPLIFIER DESIGN

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IN THlE MARKET PLACERATES to be paid in advance. Regular setting 10¢ a word, minimum charge $2.00 each; count 8 words if a box address is used.Display, 3 inches maximum, $8.80 per column inch. No discounts or commissions.SEND advertisements with remittance to the ADVERTISING DEPARTMENT, American Association for the Advancement of Science,SMITHSONIAN INSTITUTION BUILDING, WASHINGTON 25, D. C. Correct remittance must accompany instructions andcopy and advertisements will be published in sequence of completed orders.

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POSITIONS WANTEDPhysicist available. Ph.D., College teaching and industrialexperience. Desires academic or industrial position in middlewest. Box 246, "SCIENCE," Smithsonian Institution. Building,Washington 25, D. C.Entomologist-Biologist, Ph.D. Age 38. Desires teachingposition with opportunity for some research. Seven years'foreign study and travel. Two years' experience in the trop-ics. At present Associate Professor Entomology in largeeastern State Agricultural College. Box 244, "SCIENCE,"Smithsonian Institution Building, Washington 25, D. C.Electrical Engineer, Ph.D., desires associate professorshipand executive position in a western university. Experience:2 years' high-voltage research, 3 years' teaching power andcommunications, li years' industrial electronics. Age 28.Box 231, "SCIENCE," Smithsonian Institution Building, Wash-ington 25, D. C.Physiologist, P"h.D., Captain AAF desires postwar positionwith university or research laboratory. Member, AmericanPhysiological Society. Publications. Well qualified In teach-ing and experimental surgery of gastro-intestinal tract. Box238, "SCIENCE," Smithsonian Institution Building, Washing-ton, 25, D. C.Zoologist. Undergraduate and three years of graduate studyall at leading universities. 19 years of college teachinmostly Genetics, Physiology and Zoology In western state uni-versity. Publications. Stress personal relationship to stu-dent. Protestant. Box 228 "SCIENCE," Smithsonian Insti-tution Building. WVashington 5, D. C.Laboratory Assistant-preferably biological research labora-tory. Formerly penicillin, yeast research. Also tissues, gen-eral bacteriology, biology. Box 227, "SCIENCE," SmithsopianInstitution Building. Washington 25, D. C.Zoologist-PhysIologist, age 37, married, B.S.-General Sci-ence, MI.S.-Zoology. additional study In general physiologyand human physiology (Medical school) and other subjectsauxiliary to teaching or research In physiology, with eightyears research in insect physiology and toxicology, but withinterests not restricted 'to this, wants change preferably toteaching-research position. No pronounced geographicalpreference. Box 240 "SCIENCE," Smithsonian InstitutionBuilding. Washington 25, D. C.University teacher and research worker (M.D., Ph.D.) inmedical microbiology and epidemiology with wide experienceand scientific achievements in tropical and preventive medi-cine desires position in university medical school as professoror associate professor with opportunities of research. Box239, "SCIENCE," Smithsonian Institution Building, Washing-ton 25. D. C.Zoologist; B.S., Agriculture; Ph.D., Genetics; College andUniversity experience in middle west and east, desires changewith equal opportunity for teaching and research. Box 243,"SCIENCE," Smithsonian Institution Building, Washington 25,D. C.Physicist, terminating war research, is available for collegeteaching appointment. Eleven years' effective teaching; ex-tensive technical and interpretative publications. Box 249,"SCIENCE," Advertising, Smithsonian Institution Building,Washington 25, D. C.Opportunities Wanted-Physiologist is available for appoint-ment; B.A. (zoology and physiology), M.A. (physiology),Ph.D. (physiology); several years' successful teaching experi-ence; desires opportunity for teaching and research; will goanywhere; for further information, please write BURNEICELARSON, Director, Medical Bureau, Palmolive Building, Chi-cago 11.Bacteriologist-Physiologist, B.S., Graduate studies. Experi-ence as clinical bacteriologist in metropolitan hospital. Sev-eral years of research in chemotherapy. At present ResearchAssistant in large Eastern University. Desires position at$3,000. Box 247, "SCIENCE," Advertising, Smithsonian Insti-tution Building. Washington 25, D. C.Physicist, Ph.D. Professor of Physics small technical school.Selective Service and Ordnance engineering experience. Or-ganizing and coordinating activities of technical groups. De-sires enlarged opportunities In Industry or education. Mar-ried. Early forties. Box 250, "ScIENcE," Advertising,Smithsonian Institution Building, Washington 25, D. C.

22 SCIENCE-ADVERTISEMENTS VOL. 102, No. 2647~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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22 SCIENCE-ADVERTISEMENTS VOL. 102y No. 2647