May 13, 13

QUANTITATIVE ORGANIC ANALYSISvia FUNCTIONAL GROUPS

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A LABORATORY BOOK OFELEMENTARY ORGANIC CHEMISTRYBy the late Alexander. Lowy and Wilmer E. Baldwin,

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ANALYTIC GEOMETRY AND CALCULUS:A Unified Treatment

By Frederic H. Miller, The Cooper Union School of EngineeringIn this book the subjects of plane and solid analytic geometry, differential

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PRINCIPLES OF STRUCTURAL GEOLOGYBy Charles M. Nevin, Cornell University

A new chapter on the solution of problems that arise in the field and in thepreparation of reports and maps is included in this fourth edition. The authordiscusses the deformation of the earth as simply as possible, and emphasizes theunderstanding and interpretation of structures.Fourth Edition, April 1949 410 pages 250 illus. $6.00

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14 SCIENCE May 13, 1949, Vol. 109~~~~~~~

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May 13, 1949, Vol. 109 SCIENCE

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16SCIENCE May 13, 1949, Vol. 109

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May 13, 1949, VoL 109 SCIENCE

~INTERSCIENCE

QUANTUM THEORY OF FIELDSBy Gregor Wentzel, University of Chicago.Translated from the German.1949 234 pages, illustrated. 6* x93 $6.00

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SCIENCEis May 13, 1949, VoL 109

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BIOLOGYUNRESTING CELLS, by RALPH W. GERARD .

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Position Open:(a) Biological chemist: preferably Ph.D.; manufacturing chemi-cal business in highly specialized field; Middle West; $5200. (b)Assistant or associate professor and, also, instructor in anatomy,university medical school; full-time; salaries, $7000 and $4000-$5000 respectively. (c) Men with sound scientific background anddemonstrated ability to initiate and conduct research, clinical andfundamental research; department of physiology, state university.(d) Statistician: preferably with medical or biological background;Chicago area; $5200. (e) Ph.D. qualified to teach biochemistry,physiology, pharmacology; university dental school. (f) Ph.D.in soil microbiology; university appointment; $4500-$5200. (g)Two instructors in zoology; Ph.D.'s preferred; state university;West. (h) Chemist for protein isolation work; Master's degreedesired; university medical school; East. (i) Biophysicist experi-enced in handling radioactive tracers for directed research in in-fectious diseases; biochemist experienced in enzymes, proteins,exudates and modern fractionation procedures; virologist forresearch in virus infections; $5000-$6200; Middle West. S5-2Burneice Larson, Medical Bureau, Palmolive Building, Chicago. X

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May 13, 1949, Vol. logSCIENCE

May 13, 1949, Vol. 109

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