July 29, 1949, Vol. 110 SCIENCE 9

GEOLOGY. Principles and Processes. New 3rd editionBy W. H. EMMONS; GEORGE A. THIEL, University of Minnesota; CLINTON R. STAUFFER,California Institute of Technology, formerly of University of Minnesota; and IRA S.ALLISON, Oregon State College. 502 pages, $4.50

Here is a revision of a successful text for college students. Some minor changes in arrange-

ment have been made and new material added. In simple but technical style, the authors pre-

sent the fundamental concepts of physical geology and give the student a scientific view of theprocesses that operate on and in the earth. There is new emphasis on the interpretation oflandscape and geologic structure as seen from the air, with many new aerial photographs.

ELEMENTS OF GEOGRAPHY. Physical and Cultural. New 3rd editionBy VERNOR C. FINCH and GLENN T. TREWARTHA, University of Wisconsin. McGraw-HillSeries in Geography. In press-ready for fall classes

As before, the authors treat physical geography as an analysis of the resource base for nationsand peoples. This stressing of forms rather than processes gives the student a better conceptof physical geography as the science which deals with the potentialities of the physical earthfor human use. The book has been carefully revised in the light of recent developments. PartI, Physical Elements of Geography will be available in a separately published volume.

ESSENTIALS OF GEOGRAPHYBy OTIS W. FREEMAN, Eastern Washington College of Education, and H. F. RAUP, KentState University. McGraw-Hill Series in Geography. In press-ready for fall classes

Describes the principal physical aspects of the earth as a planet, and the varied environmentswhich provide for the habitat of man. Different human economies and their relationships tothe principal natural environments comprise a large portion of the book. In addition, the cul-tural aspects of some phases of human existence have been included, such as political geographi-cal settlements, urban life, etc.

PLANT AND SOIL WATER RELATIONSHIPSBy PAUL J. KRAMER, Duke University. McGraw-Hill Publications in the BotanicalSciences. In press-read for fall classes

Gives an integrated discussion of the various factors which affect the absorption of water byplants. These factors include the availability of soil moisture, the development of efficient rootsystems, the nature of the absorption process, the relation between the absorption of water andthe absorption of minerals, and the relation between water absorption and other plant processes.The fundamental scientific principles are explained as simply at possible, and many applica-tions of these principles are described.

AN INTRODUCTION TO VERTEBRATE EMBRYOLOGY. New second editionBY H. L. WIEMAN, University of Cincinnati. McGraw-Hill Publications in the Zoological

Sciences. In press-ready for fall classesThis is a revision of a college text which is noted for its sound and somewhat rigorous treatmentof the development of selected vertebrates. The treatment assumes that the chick and pigembryos are the principal forms studied in the laboratory, but the treatment is not limited tothese forms. Some work on the embryology of Amphioxus and the frog is included withoutcurtailing the work on the embryology of the mammal.

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References or abstracts on request

FRIEND, Dale G. Iron Ascorbate in the Treat-ment of Anemia. New England Journalof Med. Vol 219 No. 23 Dec. 8 '38

HEILMEYER, L. "Die Behandlung Eisenempfund-licher Anemien mit Ascorbin sauren EisenZugleich Ein Beitrag Zum Mechanismsder Eisenwirkung und zur Frage derEisenmangel Krankheit. Deutsches Archf. Klin Med. 179:216, 231, 1936.

PIJOAN, M. The Antiscorbutic Properties of aSalt of Iron and Ascorbic Acid. Science86:80, 1937.

RUSKIN, Simon L. & Merrill, Alice, "NewerStudies of Iron Ascorbate" AmericanJournal Digestive Diseases Vol 16, No. 5,May 1949

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SCIENCE July 29, 1949, Vol. 1 10

July 29,

GENEAL ELECTRIC people siay-

SAUL DUSIIMANRetired Assistant Director,Research Laboratory

THE VACUUM: Although the vacuum wvas littlemore than a scientific curiosity for ages. dur-ing the past two decades the art of producingand maintaining high vacuums has become anindustrial process of great importance. Torealize this, you need only consider the radioindustry; it depends for its very existence onthe use of vacuum processes in turning out theextremely diversified range of electron tubes-from the little ones used in yoior radio re-ceiving set to the mighty 100-kilowatt tubesused by the large broadcasting stations. Allof these must be evacuated to the highestdegree obtainable.

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STANDARDS: The terms "standards" and"standardization" have broad meanings andhave a general application, so that we come incontact with some form of standards almost(laily in our personal activities as well as ourbusiness. One place where we frequently hearof standardization is in connection with massproduction. The production of goods in largequantities makes it important that the prod-uets and parts be readily interchangeable.Experience has shown that one of the mosteffective ways of bringing this about is throughstandardization.

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*I. F. KINNARDManager of Engineering,Meter & Instrument Divisions

CLRRENT TRANSFORMERS: During more than50 vears of continuous manufacture, it has beenalmost universal practice to insulate dry-typeinstrument transformers by wrapping a fibrousmaterial-commonlv varnished cambric orcrepe paper-aroundl the transformer coils andthen impregnating this matrix with asphaltor a similar insulating compound. In many de-signs as much as one-quarter mile of crepepaper has been wrapped on the coils for properinsulation. Because of the complex configura-tion of the coils, most of this wrapping hasbeen done by hand. It has, therefore, longbeen the goal of instrument-transformer engi-neers to develop a method of molding or castingan insulating material around the transformercore and coils, thus eliminating the necessityfor hand wrapping.

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General Electric Review,June, 1949

GENERAL* ELECTRIC

July 29, 1949, Vol. 1 10 SCIENCE 13

July 29, 1949, Vol. 110

Personnel Placement

POSITIONS WANTEDToxicologist: B.S., Chemistry; graduate training, toxicology andphysiology; year's fellowship industrial hygiene; twelve years,director, industrial hygiene activities and toxicological research inindustry; for further information, please write Burneice Larson,Medical Bureau, Palmolive Building, Chicago. X

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Biochemist: Ph.D., capable of independent work. Wanted bypharmaceutical firm. Good background in basic medical sciencesrequired. Experience in enzymology desirable. Submit completepersonal and professional data. Box 281, SCIENCE. 8/12

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Stratigrapl!er and Geophysicist desired by mid-western school.Expanding Department. Ph.D. required in specialty. Rank andsalary open. Box 258, SCIENCE. R7/15-29; 8/12-26Medical Bacteriologist: M.D. degree, satisfactory interneship, twoyears' graduate experience in general pathology and medical bac-teriology, or satisfactory equivalent of the foregoing. Duties in-clude research in production of antistreptococcus grouping andtyping sera and in mechanisms of active immunity to streptococcalinfections. Beginning salary $4242. Annual increment $180 upto $5232. Apply Associate Director, Division of Laboratories andResearch, State Department of Health, Albany 1, New York. 7/29

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