NOVEMBER 3, 1939 SCIENCE-ADVERTISEMENTS

EASTMAN ORGANIC CHEMICALS

15

V/ACANCIES IFOR:(a) PROFESSIONAL OFFICER (FIELD HUSBANDRY)-SOUTH AFRICAN DEPARTMENT OF

AGRICULTURE AND FORESTRY-SALARY SCALE £ 500-25-700.(b) DIETITIAN-SOUTH AFRICAN DEPARTMENT OF PUBLIC HEALTH-SALARY SCALE £ 260-

2"300-20-00.Applications are invited from suitable candidates for appointment to the above mentioned posts in the Public Service of

the Union of South Africa.The commencing salaries will be determined according to qualifications and experience, and increments are grantable

annually, subject to satisfactory service and good conduct.Candidates should furnish full particulars regarding qualifications and experience. Original certificates and testimonials

should not be submitted in the first instance.Before appointment to the fixed establishment in a permanent capacity, the successful candidates will be required to

serve on probation for a period of not less than twelve months; they must be British subjects and have resided in the Unionof South Africa or in the Mandated Territory of South West Africa for not less than three years and they must furnish satis-factory certificates of birth and health. Successful candidates who do not satisfy the nationality and/or residential qualifi-cations will be appointed on contract until, if their services are satisfactory, they acquire eligibility for permanent appoint-ment. Proficiency in one of the official languages English and Afrikaans (or Nederlands), is an essential requirement.

The successful candidates will be provided with free first class Railway and Steamship tickets from their respective placesof residence to the centre at which they are to assume duty. Salary at half the commencing rate will be payable during theperiod necessarily occupied in travelling from the port of embarkation to the place of appointment, but no other incidentalor travelling expenses and no expenses in respect of the successful candidates' families or dependents will be paid.

Copies of publications and/or scientific reports of which the applicant is the author, must be attached to all applicationswhere possible.

Any degrees obtained by candidates must be those of Universities of recognised standing. Any qualifications additionalor of a standard enual to those which are required will also be taken into account.

Special qualifications required in respect of these posts are as follows:(a) Post of Professional Officer (Field Husbandry).

Applicants must be in possession of at least a B.Sc. degree with Botany and Chemistry as major subjects. Post-graduateexperience in Plant Physiology will be a strong recommendation.(b) Post of Dietitian.

Candidates must hold a degree in Home Economics. A post-graduate training in practical institutional management willbe a recommendation. The duties attaching to the post consist of inspecting and advising on diets and dietary arrangementsin force in Government and Provincial and Government-aided and Provincial-aided institutons in the Union of South Africa.

Application must be made on prescribed form (Z.83) which is obtainable from the Secretary, SouthAfrican Legation, 8101 Massachusetts Avenue, Washington, D. C., to whom all completed forms must beaddressed. Applications must reach the above address not later than December 11, 1939.

Inorganic Analysiswith Organie ReagentsS PEED, convenience, accuracy, and selectivity characterize

the analytical methods in which organic reagents areemployed for the determination of metals. A choice of proce-dures-gravimetric, colorimetric, or volumetric-is availablefor most of the common metals.

If inorganic analyses are an important part of your routine,write for the list of free abstracts describing the use of EastmanOrganic Chemicals.... Eastman Kodak Company, ChemicalSales Division, Rochester, N. Y.

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16 CC - DV R I E E T Vo 90 o.24

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THE SCIENTIFIC MONTHLYEdited by

J. MCKEEN CATTELL, F. R. MOULTON AND WARE CATTELLCONTENTS FOR NOVEMBER

RECENT PROGRESS IN PLANT BREEDING. PROFESSOR E. B. BABCOCK.THE LAST EPIDEMIC OF YELLOW FEVER. PROFESSOR GLENN W. HERRICK.THE RURAL COMMUNITY AS A SCIENCE LABORATORY FOR CITY CHILDREN. DR. N. ELDRED BINCEAM.THE PAN AMERICAN HIGHWAY. II. HERBERT C. LANKS.WRINKLES OF ASIA. PROFESSOR BAILEY WILLIS.

TO WHAT EXTENT IS A SCIENCE OF MAN POSSIBLE? FREDERICK OSBORN.ENGINEERING-ANCIENT AND MODERN. E. H. HULL.BAKING TECHNOLOGY AND NATIONAL NUTRITION. DR. JAMES A. TOBEY.ARISTOTLE AND THE SCIENTIFIC METHOD. RUFUS SUTER.BOOKS ON SCIENCE FOR LAYMEN:

Gone with Wind and Water; Classics of Geology; The Origin of Life.THE PROGRESS OF SCIENCE:

Harvey Cushing, An Appreciation; Seventh Assembly oj the International Union of Geodesy and Geophysics; ThirdInternational Congress for Microbiology; The Meeting of the American Chemical Society in Boston; Casualties in Science;Lunar Eclipse on October 27-28.

Published for theAMERICAN ASSOCIATION FOR THE ADVANCEMENT OF SCIENCE

SMITHSONIAN INSTITUTION BUILDING, WASHINGTON, D. C.

by THE SCIENCE PRESSNEW YORK, N. Y.

TheFoundations of Science

By H. POINCARE

Pp. xi+ 553.

Containing the authorized En-

glish translation by GeorgeBruce Halsted of "Science and

Hypothesis," "The Value of

Science" and "Science and

Method, " with a special preface

by Poincare, and an introduc-

tion by Josiah Royce. Price,postpaid, $5.00.

THE SCIENCE PRESSGrand Central Terminal New York, N. Y.

THE SCIENCE PRESSPRINTING COMPANY

PRINTERS OF

SCIENTIFIC AND EDUCATIONALJOURNALS, MONOGRAPHS

AND BOOKS

Correspondence Invited

LANCASTER, PENNSYLVANIA

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Vou 90, NO. 234016 SCIENCE-ADVERTISEMENTS

NovExm 3, 1939 SCIENCE-ADVERTISEMENTS 17

ICONSTANT TEMPERATURE EQUIPMENT

Illustration shows AmincoConstant Temperature Assem-bly, consisting of QuicksetBimetal Rustproof Thermo-regulator, LoLag ImmersionHeater, Control Box, LabStand, and Bath Jar.Complete ..... $74.50

BATHSGeneral or special purpose for wateror oil. Adjustable to temperaturesfrom - 300 to 2000 C. Constant to+ 0.250 C. With or without built-inrefrigeration.

CABINETSFor incubation, proofing, condition-ing, etc. High or low temperaturecontrol constant to ± 0.0250 C. Hu-midity control to suit requirements.

THERMOREGULATORSSensitive; rustproof. Mercury andbimetal types for air or liquid im-mersion. Hold baths constant to+ 0.020 C. Adjustable from - 300to 3000 C.

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SERVICESpecial constant temperature equip-ment designed and built to meetspecific needs. A quarter centuryof experience is at your service.

* Fully described in new Catalog 39-A

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AMEBA

MICROSCOPE SLIDESOur slides of Ameba proteus offer some

rather unusual features. Each slide con-tains many Amebae from three differentbatches, killed and fixed in three differentways. This results in a wide variety ofshapes, including those with long, slenderpseudopodia. Two staining methods wereused, one for general structure and one forprotoplasmic detail. We consider these thebest Ameba slides we've ever made and wethink that you will like them. This slideis our catalog number Z1.11 and is pricedat $1.25.

OCIC4 GENERAL ITURTX UCETS

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PURE CULTURESTurtox fills orders for thousands of Ameba

cultures each year. We furnish the speciallarge strain of Ameba proteus, developedand cultured in our constant-temperaturelaboratory for its large size and excellentshipping qualities. The cultures we furnishare pure and rich; the Amebae active andeasily studied.

1V121 Ameba, giant strain. Pure culturefor class of 12 to 25 students ............$2.50

1V12 Same, pure culture for class of 50students $3.50

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NovEwssBI 3, 1939 SCIENCE-ADVERTISEMENTS 17

SCIENCE-ADVERTISEMENTS VOiL. 90, NO; 2340

KEWAUNEE FURNITUREAssures COMPLETE SatisfactionThe wisdom of selecting Kewaunee Furniture is never

questioned. Those in authority recognize the outstand-ing position of this finer furniture in the school world.They know Kewaunee represents the best in design, thatit is flexible, efficient, space-saving furniture that pro-

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LABORATORY FURtURE EXPERTSC. G. CAMPBELL, PRES. AND GEN. MGR.115 Lincoln St., Kewaunee, Wis.

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Representatives in Principal Cities

RARE GASESAND MIXTURES

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The Linde Air Products CompanyUnit of Union Carbide and Carbon Corporation

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18

ELECTRO-M EDICALLABORATORY, INC.

HOLLISTON, MASSACHUSETTS, U.S.A.

PRECISION INSTRUMENTSFOR

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HENRY TROEMNERThe Standard of Excellence for 99 years.

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Catalog 1929S

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SCIENCE-ADVERTISEMENTS

NEWVI-SIOGRAPH FILMROLS

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Complete Set of Six

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school course in physics and is priced at only$12.00, or slightly less than 7 cents per picture.

Each roll is accompanied by lecture manual and

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0

See our catalog, either No. 46 or 48 for complete listings ofPhysical Instruments, Apparatus and Supplies.

EPPLEY

THERMOPILESfor

RADIANT ENERGY

MEASUREMENTS

A view of some of the apparatus used forcalibrating thermopiles at the Eppley Lab-oratory, Inc.

Adequate manufacturing, testing andcalibrating equipment in the hands ofour skilled and experienced techniciansinsures satisfaction to the users of Ep-pley Thermopiles.

We are prepared to furnish thermopilesof either bismuth-silver or copper-con-stantan, mounted in vacuum or air typecases. We also furnish thermopilesand mountings especially designed tomeet individual needs. A card willbring you our Bulletin R-3 which con-tains illustrations, sample curves, com-plete descriptive matter, prices, refer-ences, etc., with regard to EppleyThermopiles.

THE EPPLEY LABORATORY, INCSCIENTIFIC INSTRUMENTS

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N0VF,3BZR. 3, 1939 19

20 SCIENCE-ADVERTISEMENTS VoL. 90, No. 2340

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NOVEMBaR 3, 1939 SCIENCE-ADVERTISEMENTS 21~~~~~~~~~~~~~~~~~~~~~~

EXPERiMmENTAL WORK in the PurinaResearch Laboratories and the expe.

rience of many other laboratories showsthat Purina Laboratory Chows providesufficient nourishment, vitamins and min.erals to maintain long life and vigor instock and breeding colonies.For example, at the Purina Experimen.

tal Rabbitry, it has been found that PurinaComplete Rabbit Chow will keep does inexcellent condition while kindling sixlitters and raising 30 to 35 young a year.Other experiments with rats and micealso show that Purina Laboratory Chowspromote long life and vigor!__ ___. TEAR HERE-__ _PURINA MILLS, 861 Checkerboard Square, St. Louis, Mo.

Please send sample of diet for following animals and bulletingiving ingredients, cost and feeding directions.

I keep about (No.) .... Rats ....Mice ... Dogs ... Rabbits ... Guinea Pigs.Name ............. Dept.Institution ............. Address

GAERTNER PRECISIONCHRONOGRAPHS

SPEEDS:I to 1000 mm. per second

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TAPE CHRONOGRAPHSDRUM CHRONOGRAPHSTUNING FORKSPRECISION CLOCKS

DESCRIPTIVE BULLETINTON REQUEST

THE GAERTNER SCIENTIFIC CORPORATION1204 WRIGHTWOOD AVE. - CHICAGO, ILL.

NovzMBEX 3, 1939 SCIENCE-ADVERTISEMENTS 21

22SCIENCE-ADVERTISJ.MENTS 2340

ZEISS

ABBE REFRACTOMETERFor determining the refractive indices and meandispersions of liquid, plastic and solid substances.The refractive Index Is read off a graduated sector withoutany calction whatever. - The mean dispersion of thesubstance under examination is calculated from readingsfurnished by the graduated drum of the compensator.

Range nD =1.3 to nD = 1.7. Accurate to within abouttwo units of the 4th decimaL With heatable prisms.Complete in case with thermometer and dispersion table..

Prices and literature on request.

CARL ZEISS, INC.4 8 5 Fi ft h Av e n u e 728 So Hil l StreetN E W- Y 0 R K ci1LE LOS AN-GELESL

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22 SCIENCE-ADVERTIS,EMENTS- VoL. .90, No. 2340