OF THE MORE THAN 3/09 EASTMAN ORGANIC CHEMICALS

For sub rosa branding...

Chrysene (Eastman 4217) and An-thracene (Eastman 480-X) are use-ful, among other things, for catchingculprits. Imperceptible dustings ofchrysene fluoresce violet; ditto an-thracene, but in another hue. An en-tomology prof we know of has foryears had his own private mixture ofthe two, which he very, very lightlydusts over every field collection ofspecimens turned in by his studentsat the end of the term. The charac-teristic shade of blue-violet fluores-cence excited by an ultraviolet lamphas trapped many a junior trying toget by with a senior fraternitybrother's bugs. Have you any "bugs"in your business you want identified?

seas shipment. Nowadays there areother, better inhibitors. But whatabout the laboratory worker whowants a small quantity of a substi-tuted hydroquinone? He could startwriting letters to tonnage producersof petroleum additives. On the otherhand, if he values his time, he justopens his Eastman Organic Chem-icals catalog.

Cadmium-conscious...CH3\CH3-NCHs/ L I

Trimethylphenylammonium Iodide(Eastman 4423) is a quaternary am-monium salt we first prepared for amidwestern zinc firm back in theearly thirties. Not long ago theytold us there was no objection torevealing that they use it in a method

they worked out for determiningcadmium in their products, in con-centrations ranging all the way from.006% to 90%. It seems to be ahighly selective precipitant for cad-mium in the presence of any amountof zinc. Zinc smelters generally areusing it in their operations. It's alsoused to detect small amounts of cad-mium in electrolytes and plant-wasteliquors. If you're cadmium-con-scious, we'll be glad to send you fulldetails.

Perhaps more important for yourown research, development, or ana-lytical work are others of the morethan 3400 compounds you can orderfrom our List No. 37. If you don'thave a copy, write to DistillationProducts Industries, Eastman OrganicChemicals Department, Rochester3, N. Y. (Division ofEastman KodakCompany).

"Obsolete" to some ...

(C5H11)2C6H2-1,4-(OH)2Di-tert.-amylhydroquinone (Eastman3142) was an important chemical ofcommerce at one time. It was usedto prevent discoloration and gumformation in kerosene on long over-

2~I ~~Eastman Organic Chemicalsfor science and industry

Also ... vitamins A and E ... distilled monoglycerides ... high vacuum equipment

VAN SL YKEMANOMETRIC BLOODAPPARATUS-~~~ Ai

GAS

HE original Van Slyke principle andtechnique remain unchanged, but these im-provements are noted in this present-daymodel: more substantial construction, ajust-able leveling bulb, new glare-proof manom-eter and burette illumination, independentlycontrolled lights and motor, mounted washbottle and receptacles for glass tips of suc-tion and distilled water tubes contribute toease and accuracy of operation.Manufacturers Distributors

WRITE

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NOW! Bring your AAAS Directoryup-to-date with the NEW,

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6 x 9 inches, clothbound, 392 pagesJanuary 1951 ............ . $5.50AAAS members' prepaid orders. $4.75

combination offer .

AAAS Proceedings and Direc-tory, 1940-1948, plus the newCentenary Supplement - bothvolumes in one order-$10.50AAAS members' prepaid orders

-$8.50* order now, from AAAS -

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a CENTENARY SUPPLEMENT 0 special COMBINATION OFFER

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Supplied in 500 cc vials, sterile, ready for use in-travenously containing 6% gelatin (knox) and0.5% glutathione S H (reduced form) or S S(oxidized form) as desired.Bibliography on Request

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7j x 1Of inches,double column,clothbound,320 pages

Symposia presentedto commemorate thefirst hundred yearsof AAAS include42 papers by lead-ing scientists in thir-teen major fields:

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SCIENCE, Vol. 114

ID

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16

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