SCIENCE-ADVERTISEMENTS

From thc men who know . . .unqualified praise

THEORY OF X-RAY DIFFRACTION-- ~IN CRYSTALS

By W. H. ZACHARIASEN,Associate Professor of Physics, University of Chicago

OFFERING a complete presentation of the fundamental theories of crystalstructure, this book has been welcomed by crystallographers, physicists, andchemists. Some of the reasons for its success may be found in the followingcomments.

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January 1945 255 pages

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NEW BLAKISTON BOOKS

HOBERPhysical Chemistry of Cells and Tissues

By RUDOLF H6BER, M.D.Department of Physiology, University of Pennsylvania Medical School;and Collaborators.

Dr. Hober and his collaborators present in this work an intelligible accountof the material and developments in various fields of physical chemistry intheir application to general and medical physiology. Emphasis is given tonew developments in the field of submicroscopic structures, as evidenced bythe complex organic macromolecules, the fibres, interfacial films and mem-branes. The significance of the structural aspect especially in the analysisof contraction, excitation, absorption, secretion and other processes is pointedout, and alterations of the ultrastructures with metabolic changes are corre-lated. Thus is offered a new approach to the problem as to how, in celllife, chemical energy is transformed into mechanical or osmotic work.

BENSLEYPractical Anatomy of the Rabbit E'd

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SCIENCE-ADVERTISEMENTS

STORER'S

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14 SCIENCE-ADVERTISEMENTS VOL. 102, No. 2645

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SEPTEMBER 7, 1945 SCIENCE-ADVERTISEMENTS 15

-~~ea Z cmdta 7ez4THE EARTH AND MANBy D. H. DAVIS

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SCIENCE-ADVERTISEMENTS VoL. 102, No. 2645

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A New Eastman Spectroscopic PlateofExtreme Resolving Power

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20 SCIENCE-ADVERTISEMENTS VOL 102, No. 2645

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T E MARKET PLACERATES to be paid in advance. Regular setting 10 a word, minimum charge $2.00 each; count 8 words if a box address isused. 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 Advancementof Science, SMITHSONIAN INSTITUTION BUILDING, WASHINGTON 25, D. C. Correct remittance must atcom.pany instructions and copy and advertisements will be published in sequence of completed orders.ADVERTISERS are requested to mention in their announcements the section of the country in which a position is open or de-sired to ensure replies only from employers or prospective employees geographically available.SUBMIT copies, not original documents, when replying to advertisements. Advertising circulars will not be forwarded and tothat end all letters will be opened for inspection at the forwarding office.

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