Kodak reports to laboratories on:a radiological safety device ... tocopherol and an iron-bound policy ...snap shooting in depth

Neutron filmSurely people whose work may ex-pose them to neutron irradiationare not dependent on advertising bya film manufacturer to alert them totheir possible personal perils.We wish nevertheless to spread

upon the record word that anyKodak Industrial Dealer is now pre-pared to sell you for $11.25 a cartoncontaining 150 1¼"/4 x 1/'" KodakSpecial Nuclear Track NTA FilmPackets. These look just like thepaper-sheathed rectangles of x-rayfilm which we turn out by the mil-lions for the dentists. The film isquite different.By virtue ofcertain adjustments of

silver content, silver halide crystalsize distribution, and susceptibilityto the action of developers, this filmreveals tracks of individual ionizingparticles that have passed throughthe emulsion. It captures no picturesand is read not with a densitometerbut with a microscope. One countsin, say 50 fields, the number ofstraight lines formed by groups ofdeveloped grains after the film hasbeen worn in a badge for, say, twoworking weeks.

Neutrons themselves, of course,are not ionizing particles. The tracksseen are those of either recoil pro-tons knocked out of the organic ma-terial of the emulsion by fast neu-trons, or of protons originating fromthe reaction of thermal neutronswith nitrogen, viz. N'4(n,p)C'4.Eastman Kodak Compatnv, Indclustial

Photographic Division, Rochester 4,N. Y., can keep you in touch with what'snew in the use of the photographic emul-sion as a radiological sapftv device.Make siure we know of your initerest.How in the age ofneuitront economics canwe have a healthy scienice without healthyscientists ?

OfferVitamin E is one of the principalproducts of one of our plants. Wehave never sold as much as a milli-gram of it in dosage form. A greatdeal of our production goes out in

55-gallon drums to some of theworld's most honored pharmaceuti-cal houses. A fast-growing portiongoes to manufacturers of animalfeeds, not on the strength of scareadvertising to farmers, but of soberand practical judgments stemmingfrom research by the millers' ownnutritionists and by the state agri-cultural colleges.

Yet, despite mountains of data,vitamin E plays its physiological rolebehind a tantalizing, exasperatingveil. We do whatever we can to pene-trate it, and we encourage as manyother qualified investigators as wecan reach to join us in the endeavor.Though pure d-x-Tocopherol and

d-a-Tocopheryl Acetate are sold forinvestigational use as Eastman Or-ganic Chemicals, we are pleased toannounce in this case an exceptionfrom an iron-bound policy that hasmade it possible to build up the greatcollection of research organics to itspresent stature in the world of sci-ence. The policy says that since allEastman Organic Chemicals are in-tended for research, none can bemade available gratis, however wor-thy the research.Now we say that if you are en-

gaged in biological experiments inwhich vitamin E is a major variable,we shall be happy to consider sup-plying without charge reasonablelaboratory quantities of either thepure free tocopherol or its pure ace-tate. This material contains only thestereoisomer which occurs in na-ture, undiluted with associated lip-ids or isomers of lesser biologicalactivity.

Inquiries and corresj'onbdence on sci-entific aspects of vitamin E should beaddressed to Dr. Norris D. Embree,Director of Research, Distillation Prod-ucts Industries, Rochester 3, N. Y. (Divi-sion of Eastman Kodak Compancv).

The stereo storyYour Kodak dealer is now in a po-sition to offer you a top-qualitystereo camera and viewer at a con-venient price, and he may be able

to extend payment terms that makeit even more convenient.

The Kodak Stereo Camera toler-ates and thrives on rough guesses.After you have decided which of thefour available shutter speeds is ap-propriate, you set for "bright,""hazy," or "cloudy-bright," and thisautomatically matches the properlens opening to the shutter speedselected. Similarly, you focus for"close-ups," "groups," or "scenes,"and the great "depth" of the short-focus lenses takes care of you. Aspirit level visible in the viewfinderindicates when the camera is level,for levelness is most important instereo. There is no film threading,because the end of your roll of No.335 Kodachrome Film just dropsinto the take-up drum. The shutteris cocked automatically as you windthe film for each exposure. It can'tbe snapped again until the film isadvanced.For viewing the brilliant and life-

like results, you have a choice oftwo Kodaslide Stereo Viewers. Bothfocus by movement of the slideholder rather than the eyepiece, sothat the focus doesn't get jarred ac-cidentally. A lever adjusts lens spac-ing to the individual skull anatomy.Model I is battery operated. Model1I plugs into the nearest electricaloutlet, has a brightness control andcolor-corrected doublet lenses. Itconverts quickly to battery opera-tion if desired.

$84.50 for the camera, $12.75 for theXModel I viewer or $23.75 for the Model11: $4.65 for a 20-stereo-pair roll ofKodachrome Film, including process-ing, mounting in Kodaslide StereoMounts, and return postage.

This is one of a series of reports on the many productsand services with which the Eastman Kodak Company andits divisions are... serving laboratories everywhere

Prices include Federal Taxwhere applicable and aresiubject to changewithout noiice.

SLEEPING ACCOMMODATIONS AT 121st AAAS MEETINGBerkeley, California, December 26-31, 1954

The hotel, motel, and dormitory sleeping accommodations-their rates and the application coupon below-are for your convenience in making room reservations in Berkeley. Please send your application directly to theAAAS Housing Bureau and thereby avoid delay and confusion. The experienced Bureau will make assignmentspromptly; a confirmation will be sent you in two weeks or less. Single rooms may become scarce; double roomsfor single occupancy cost more; if possible, share a twin-bedded room with a colleague-and also save. Mail yourapplication now to secure your first choice of desired accommodations. All requests for reservations must give adefinite date and estimated hour of arrival and also probable date of departure.

HOTELS SINGLE DOUBLE TWIN SUITEClaremont 5.00-11.00 8.00-13.00 8.00-1 3.00 14.00-20.00Durant 4.00- 7.00 6.00- 9.00 6.50-10.00 10.00-16.00Shattuck 5.00-10.00 7.00-10.00 7.50-10.00 10.00-18.00Other hotels 3.00- 5.00 3.50- 5.00 4.00- 6.50 7.00-10.00

(Note: Most hotels have singles without private bath at $2.00-$3.50 per night)MOTELS FAMILY ROOMS

Berkeley Plaza 5.00 6.00 7.00 8.50-12.00California 4.00- 4.50 4.50- 5.00 5.50 6.00- 7.00Golden Bear 4.50- 5.00 5.00- 7.00 6.00- 8.00 7.50-10.00Other motels 4.00- 5.00 4.00- 6.00 5.50- 8.50 6.00-12.00

Dormitory Accommodations: NOTE: The 766 units in the University of California dormitories are primarily for students,younger faculty members, and those not on expense accounts. Occupancy, two persons per room; rate, $2.00 the first night,$1.00 per night thereafter, per person.

International House: Singles only, without private bath, $2.50 per night.For a discussion of the headquarters of the participating societies and sections, please see Association Affairs, Sc.ience, July 23, orThe Scientific Monthly, August.

- .___--____ THIS IS YOUR HOUSING RESERVATION COUPON - . -AAAS Housing Bureau2223 Fulton Street Date of Application.Berkeley 4, CaliforniaPlease reserve the following accommodations for the 121st Meeting of the AAAS in Berkeley, Dec. 26-31, 1954:

First Choice .. ..... Second Choice ........ Third Choice ....................(State name of hotel, motel, or other`)

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Only $18.00In lots of S or more $16.20

lumination for the entire laboratory tabletop.

Light supplied by the 150 watt cleardaylight lamp is evenly diffused by theopal glass globe. Both globe and lamp areinexpensive replacements available at anyelectrical supply store. Top-vented droprim shade assures cool operation. Thestable base is heavy enough to preventtipping. Attractive maroon wrinkle enamelfinish resists usual laboratory reagents.

Dept. K1Send information on the new No. 710 Illumi.nator to:

Name...................................

Address.................................

City Zone.

State...................................

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