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8 November 1946 9

0 0.1

Antibacterial Activity

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E. Bacillus pyocyaneus * F. Mycobacterium tuberculosisThe numerals indicate micrograms of Streptomycin per cc. of agar.

1.6

6.4 26. 104.

THESE photographs show the inhibitory action of increasing concen-trations of Streptomycin on a strain of six representative organisms URINARY TRACT INFECTIONS

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An important publication for all chemists, engineers, and other scientists interested in consultingthe original Russian sources. This book is a scientifically organized reference to 80,000 terms,with a comprehensive coverage of organic and inorganic chemistry, and chemical technology andmineralogy. Also extensively covered are metallurgy, mining, geology, engineering, physics, botany,pharmacy, and the more common terms in agriculture, medicine, aeronautics, meteorology, and mili-tary science. Besides the terms used in research and academic work, the book includes those usedmost frequently in industry.

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Personnel PlacementCHAGES FOR CLASSIFIED ADVERTISINGRegular setting 10¢ a word. Minimum charge $2.00for each insertion. A box number counts as 8 wordsof the advertisement (e.g. 20 words plus box numberequals 28 words). Make checks payable to the A.A.A.S.All insertions must be accompanied by correct remit-tance and sent to the Adv. Dept. A.A.A.S. Pleaseaddress replies as follows: Box number, SCIENCE,1515 Mass. Ave., N. W., Wash. 5, D. C.

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19

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'Trade Mlask. General Chemlial Company

GENERAL CHEMICAL COMPANY40 RECTOR STREET, NEW YORK 6. N. Y.

Sadei and Technisal Service Offices: Albany * Atlanta * Baltimore * Birmingham * BostonBridgeport * Buflalo * Charlotte * Chicago * Cleveland * Denver * Detroit * HoustonKansas City * Los Angeles * Minneapolis * New York a Philadelphia * PittsburghProvidence * San Francisco * Seattle * St. Louis * Wenatchee and Yakimna (Wash.)

In Wisconsin: General Chemical Wisconsin Corporation, Milwaukee, Wis.In Canada. The Nichols Chemical Company, Limited h Montreal * Toronto M Vancouver

Vapor pressure (p.s.;. abs.):

-30° C 6.0

-10° C 14.7

10° C 31.2

30° C 59.0

I--

All Cpm t£.l; . C4Q1tI cr t IW

HEMOGLOBIN DETERMINATIONSwith the New Spencer Hb-Meter

here is by far the simplest, fastest, mosteconomical way to make hem6globin de-terminations of laboratory accuracy.

Carried in pocket or bag, the new lib-Aleteris instantly ready for use at the hospital,office., or patient's bedside. It operates eitherfrom the self-contained dry cells or from anyelectrical outlet. No diluting fluids or volu-metric measurements are necessary. Notables or calibration curves need be con-sulted. The results appear directly in gramsper 100 cc or in terms of percentage normalfor any one of three recognized standards.

See your local supplier for further informa-tion about this companion to the well-known"BRIGIIT-LIlNE" llaemacytomneter .. . orvyrile Dept. L2.

Blood isdroppeddirectly onglasschambher.

Blood isquickly

B heinolyzedby agitatingwithhernolysisapplicator.

Chamber isC inserted andc the fields

misatched.

Conrentration Slay>{otw Be ReadI)irectly FromIlhese Scales

American ID OpticalCOM PA NY

Scientific Instrument DivisionBuffalo 15, New York