December23,1949, Vol.110 SCIENCE 11~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

QUANTITATIVE ULTRAMICROANALYSISBy Paul L. Kirk. Collects and organizes the data on ultramicroanalysis, covering, with com-plete assurance of accuracy, all essential techniques for use of these methods. Viewed from astrictly chemical aspect, all methods are adapted to general application. Among the main sub-jects treated are: Volumetric Apparatus and Technique; Colorimetry: Apparatus and Tech-nique; Microgram Titrimetry; Metallic Constituents: Titrimetric Methods; Volumetric Gas Meth-ods; Spectrophotometric Methods; and Physical Methods.

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December 23, 1949, Vol. 110 SCIENCE 11

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December 23, 1949, Vol. 11012 SCIENCE

December 23, 1949, Vol. 110 SCIENCE 13

Academic Press Announce_PHYSICAL CHEMISTRY of HYDROCARBONSEdited by Adalbert Farkas In Two Volues

The last decade or two has witnessed an unprecedented development andramification of hydrocarbon technology. The purpose of this work is to summarize the physico-chemical basisof the new techniques and methods recently adopted by the hydrocarbons industry, and to help the researchworker in exploiting these procedures more extensively and more intensively. "Physical Chemistry of Hydro-carbons" has been written primarily for the chemist, engineer, or physicist engaged in hydrocarbon tech-nology or research.

VOLUME 1, 1950, approx. 460 pages, Illustrated, about *8.50The Chemical Bond in Hydrocarbon Molecules. By G. W. WHELAND.The Molecular Structure of Hydrocarbons as Determined by Spectroscopy and Electron X-Ray Diffraction.

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VOLUME AI, 1950, in preparationDensity, Refractive Index and Surface Tension of Hydrocarbons. By STEWART S. KURTZ, JR.Viscosity of Hydrocarbons. By ROBERT W. SCHIESSLER.Heat Capacity of Hydrocarbons. By J. G. ASTON.Critical Properties of Hydrocarbons. By R. H. OLDs.Optical Activity of Hydrocarbons. By ROBERT L. BURWELL, JR.The Mechanism of some Hydrocarbon Reactions. By R. C. HANSFORD.Separation and Purification of Hydrocarbons by Solvent Extraction. By J. C. ELGIN.Separation and Purification of Hydrocarbons by Adsorption. By ARvo JUHOLA.

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@Academic Press inc., Publishers (!j) |125 East 23rd Street, New York 10, N. Y.

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December 23, 1949, Vol. 110 SCIENCE 13

SCIENCE December 23, 1949, Vol. 110

LIMNOLOGICAL ASPECTS OFWATER SUPPLY AND WASTE DISPOSAL

v +87 pages-6 x 9-illustrated -clothbound-7949

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IThis volume of 20 papers treats of a field of science of rapidly

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December 23, 1949, Vol. 110

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PHOTOSYNTHESIS IN PLANTS, 22 chapters, a Monographof the American Society of Plant Physiologists; 500 pages, 129illustrations, cloth, 1949-$7.00. IOWA STATE COLLEGEPRESS, Office 102, Ames, Iowa. R 12/23

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18SINEDcme 2,14,Vl

Are YOU destroying valuable information?_ Every issue of Science contains information and reference ma-

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THE RICKETTSIAL DISEASES OF MAN

This symposium volume is a comprehensive survey of the general field of Rickettsialdiseases in man. Among the contributors appear the names of many of the foremostAmerican authorities on this important and relatively new field of medicine.

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