Kodak reports to laboratories on:a reagent for the isolation of ketones . . . how to learn the fundamentals ofradiography... hunting cosmic ray particles without a camera

To capture ketonesLet us say you wish to demonstratethe particular ketone setup whencearises the subtle flavor that makescaraway seeds taste so good incookies or in fresh rye bread. p-Hydrazinobenzenesulfonic Acid hasthe useful property of forming eas-ily cleaved condensation productswith ketones but does not react atall with aliphatic aldehydes. Fromthe cleavage of the condensationproducts, yields of 70% and betterare reported. You cannot do thiswith aromatic aldehydes becausethey give only addition compoundsthat are not converted into true con-densation products by splitting offwater. Thus you have a reagent forthe separation of aliphatic and iso-cyclic ketones from caraway seedoil or whatever other essential oilsinterest you.For a procedural abstract on isolating

ketones with p-Hydrazinobenzenesul-fonic Acid (Eastman 1129), or a copyof the catalog that lists more than 3500other Eastman Organic Chemicals,write Distillation Products Industries,Eastman Organic Chemi-cals Department, Roches-Iter 3, N. Y.

RadiographySuppose you, desire to find out alittle more about the practical as-pects of working with x-rays thanwhat you have been able to observeas a medical or dental patient andrank layman. One way to informyourself painlessly and withoutnuisance to acquaintances who areprofessional in the field is throughour 100-page book, "The Funda-mentals of Radiography." Just is-sued is the rewritten eighth editionof this work, which has introducedmany thousands of practicing x-raytechnicians to their careers.The typical reader the author has

in mind is an intelligent and earnestyoung person who has never pre-viously given much thought to thedifference between an anode and acathode but is willing to learn. Cer-

tain of the earlier pages you canprobably afford to pass over ratherquickly to get to the parts where we

review the geometry of x-ray imageformation, the effect of kilovoltageon what is shown, scattered radia-tion and its control, intensifyingscreens and how to use them, theselection of film and processingprocedures, calculation of expo-sures, how to get more contrast,how to get more detail, how in gen-eral to run a radiographic operationfor consistently good results andmaximum personal safety. Theviewpoint is essentially that of themedical x-ray clinic, but the con-tent can be useful elsewhere-toyou yourself or to a newcomeryou'd like to interest in the topic.

To get a copy of "The Fundamentalsof Radiography," one simply drops anote to Eastman Kodak Company,X-ray Division, Rochester 4, N. Y. If,however indirectly, it results in an incre-ment to the ranks of the radiographers,we shallfeel amply rewarded.Hobby?Not only is there no need for a cam-era with Kodak Nuclear Track Platesand Pellicles, Type NTB3, but onedoesn't even need to open the orig-inal shipping package to exposethem. Their function is to pick updevelopable tracks of the ceaseless,silent rain of cosmic ray particlesthat stream through the atmosphere-electrons, protons, deuterons,mesons of the several breeds, posi-trons, multiply charged heavy ions,V-particles, etc.

(The number of species seems togrow with every meeting where high-

energy physics is on the agenda; thetheoreticians are way behind ontheir explanations.)Any wrapping material we can

put around the emulsion not onlyfails as a shield but even acts as asource of additional ionizing parti-cles knocked out of the material bycosmic radiation. This makes TypeNTB3 just about our most perish-able product. We keep no stock,even wait till the last moment tomake the emulsion, get it to thephysicists by the fastest means, andwarn them to process as soon aspossible.Associating Type NTB3 with

urgency in our minds, we hadn'tthought till just the other day of aleisurely experiment with them: letus, we said, simply leave a few dozenpackages of NTB3 plates and pelli-

cles on the lab roof for a while,somewhat after the casual mannerin which M. Becquerel opened thefield of nuclear physics. After proc-essing, will we find tracks of inter-esting particles and events? Howmuch searching with a good high-power microscope will it take to findthe interesting tracks against thecamouflaging background of sec-ondary electron tracks that the pro-fessionals avoid by exposing in high-altitude balloons? -We'll let youknow if we find anything that mightbe encouraging to the dedicatedamateur.A dozen 1' x 3' Kodak Nuclear

Track Plates, Type NTB3 cost $6.40 in25-, 50-, or 100-micron emulsion thick-ness. Orders are placed with a localKodak Industrial Dealer, whose name isobtainable from Eastman Kodak Com-pany, Industrial Photographic Division,Rochester 4, N. Y. Larger sizes, 150- and200-micron emulsions on plates, and pel-licles cost more. A pellicle, by the way, isa sheet ofunmounted emulsion one-quar-ter millimeter thick.

This is one of a series of reports on the many productsand services with which the Eastman Kodak Company and

Price quoted is subject tochange without notice.

Its divisions are... sewving laboratories everywhere

UNIVERSITY PRESS

Age and AchievementBy HARVEY C. LEHMAN. Certain assumptionsabout man's creativity in relation to his chrono-logical age have become so widely accepted as factthat the findings of this book will surprise both gen-eral reader and specialist and may have far-reachingeffects in psychology and in education. This statisti-cal evaluation of achievement in relation to age as-sembles an incredible amount of factual informationon the ages of superlative achievement in everyfield from prize-fighting to philosophy. The authoris professor of psychology at Ohio University. Pub-lished for the American Philosophical Society.

368 pages. Charts and graphs. $7.50

Man and EppidemicsBy C.-E. A. WINSLOW. The conquest of epidemicdiseases is one of the outstanding achievements ofman in the past century. This book presents for thegeneral reader the fascinating account of the modernmethods of control that make it possible for theaverage citizen to draw pure water from the faucet,enjoy a sanitary milk supply and eat food withoutfear of infection."A scholarly exposition of the conquest of epi-

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Order from your bookstore,Princeton University Press

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Acetyl Choline Chloridep-Aminobenzoic Acid

Ascorbic AcidBiotin, CrystallineBiotin Solution

Calciferol, Vitamin D,Calcium Pantothenate

Choline ChlorideDL Desthiobiotin

Folic Acidi-Inositol

2-Methyl Naphthoquinone (Menadione)Niacin (Nicotinic Acid)

Niacinam'ide (Nicotinamid)Pyridozine Hydrochloride (Vit. B.)

RiboflavinRutin

Thiamine HydrochlorideTocopherol, Alpha

A READY REFERENCEThat will Save Time for You

Use this catalog as a "one stop" source S Eof Amino Acids, Vitamins, Carbohydrates,Adenylates, Nucleates, Purines, Pyrimi-dines, Tetrazolium Salts, Enzymes, Micro-biological and Bacteriological Media,,Complete Animal Test Diets and YOUR COPYIngredients for investigational use. TODAY

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New Top-DriveLaboratory HomogenizerHere, at last, is a laboratory homogenizer speci-fically designed to simplify the many problemsentailed in laboratory homogenization-bothmicro and macro-and still yield superior results.Its chief advantages over existing apparatusare . . .* UNPRECEDENTED SPEED-universal heavy dutymotor controlled by variable transformer gives speedsfrom 100 to 27,000 R.P.M.

* ONLY 15 to 120 SECONDS HOMOGENIZINGTIME-high R.P.M. and razor sharp replaceable 18-8stainless steel blades give maximum efficiency.IDEAL FOR ELECTRON MICROSCOPE PREPA-RATIONS, ETC.-works with micro volumes of 0.2 to0.5 ml. Transition Flasks for volumes from 0.5 to 5 ml.are also available.HANDLES MACRO VOLUMES OF 5 to 50 ml.-special design of fluted flask and blades permit this versa-tility.

* AEROSOL FREE ASSEMBLY-for both micro andmacro homogenization, precision machined cap andwasher made. of teflon are available. Assembly's uniquedesign eliminates chance of harmful aerosols escaping.

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* SIMPLE TO STERILIZE-shaft, blades, homogenizingflask and cap may be placed in autoclave as a unit.

R63-186 Micro Homogenizer for volumes from 0.2to 0.5 ml complete with stainless steel micro cup,shaft. blades and aerosol free assembly, asillustrated ..... $96.00R63-186C Attachment for converting to macrohomogenization consisting of glass (Pyrex brand)fluted flask, shaf and blades aerosol free as-sembly, plastic cooflng cup and clamp .. $30.00

All prices F.O.B., New York, N. Y.

For complete details about Homogenizerand its many accessories write for Bulletin

Ocoe 6 931Oetober 16, 1953 is

MINIATURE MERCURY VAPOR LAMPtThis miniature mercury vapor lamphas a special glass housing to per-

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FILUORESCENT PIGMENTSBrightest glowing, basic concentrated phosphors, noinert ingredients. Available in many colors. Red,White, Blue, Green, Yellow and Orange. Mix withclear lacquer for painting.SAMPLE SIZE (specify color) ...... ......... 35¢ eachCOMPLETE SAMPLE KIT (6 colors) .. $1.75ONE OUNCE BOTTLES (specify color) ..... 50¢ eachCOMPLETE 1 oz. KIT (6 colors) .......... $3.00

No. 2444 POCKET DIFFRACTIONSPECTROSCOPE

This is a very convenient pocket spectro-scope for general laboratory and experi-mental use. Diffraction grating used formaximum spectrum definition. Protected bya glass cover to prevent dust from entering.An adjustment for accurately focussing thespectrum is provided. A scientific instru-ment. Available for the first time in smallsize.

No. 2444. Pocket spectroscope, in leather case.Special Price $12.50

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These are government releasedBritish snooperscope tubeswhich employ the special sim-plified design, making con-struction of experimental mod-els possible with simple handtools. Highly sensitive, theyprovide a bright clear image

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Supply Limited! Special $14.95PRISM SPECTROSCOPE

Used for very weak light analysis as it contains a setof five optically ground prisms for maximum lighttransmission. Passes several times more light thandiffraction types. Adjustable slit and focussing makethis an ideal laboratory instrument. The Model 2459has a comparison prism for standardizing. Perfect fortests of filters, glow lamps, chemical compositions.Comes in beautiful lined case.Prism Spectroscope, Model 2458 ...... ........ $49.50Prism Spectroscope, Model 2459 .............. 52.95

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4

GET YOUR ADVANCE COPYof the General Program-Directoryof the Boston Meeting of the AAAS

By first class mail - early in DecemberThe General Program-Directory of the 120th Meeting of the AAAS in Boston, December 26-31,

1953, will be available to anyone, at cost, within the first week in December-whether he can attendthe Meeting or not. You will want the General Program-Directory for your reference shelf.

0

Program content

1. The General Symposia: "Species Which Feed Man-kind" and "The Sea Frontier."

2. Programs of the 18 AAAS sections and subsections(symposia and contributed papers).

3. Programs of the more than 40 participating societies.4. The Special Sessions: AAAS, Academy Conference,

Conference on Scientific Editorial Problems II, Con-ference on Scientific Manpower III, British AAS,National Geographic Society, Phi Beta Kappa,RESA, Sigma Xi.

5. Details of the Mechanics Building and downtownhotels.

6. Titles of the latest foreign and domestic scientificfilms to be shown in the AAAS Science Theatre.

7. Exhibitors in the 1953 Annual Exposition of Scienceand Industry and descriptions of their exhibits.

Directory content

1. AAAS officers and staff for 1953.

2. Complete roll of AAAS presidents and their fields.

3. The 245 affiliated organizations.

4. Historical sketch and organization of the Associa-tion-and the new Constitution and Bylaws.

5. Publications of the Association.

6. AAAS Awards and Grants-including all pastwinners.

7. Membership figures by sections.

8. Section committees (Council members) in detail.

9. Local committees.

10. Future Meetings of the AAAS-through 1958.

Advance RegistrationAdvance registration has these decided advantages: 1) You avoid delay at Registration Desks upon arrival;

2)You receive the General Program-Directory in ample time, unhurriedly, to decide among events and sessions youparticularly wish to attend; 3) Your name is posted in the Visible Directory as the Meeting opens.

The following coupon may be used both by advance registrants and by those who wish onlythe advance copy of the General Program-Directory.

--- THIS IS YOUR COUPON FOR AN ADVANCE COPY OF THE GENERAL PROGRAM-DIRECTORY --

I a. O Enclosed is $2.50 for my advance Registration Fee which brings me the Program-Directory, ConventionBadge, and all privileges of the Meeting.

lb. E Enclosed is $1.50 for only the Program-Directory. (It is understood that, if I should attend the Meetinglater, the Badge-which is necessary for all privileges of the Meeting-will be secured for $1.00 more.)

(Check one)

2. FULL NAME (Dr., Miss, etc.) ....................................................................(Please print or typewrite) (Last) (First) (Initial)

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6. CONVENTION ADDRESS .......................................................................(May be added later, after arrival)Please mail this Coupon and your check or money order for $2.50 or $1.50 to the

AMERICAN ASSOCIATION FOR THE ADVANCEMENT OF SCIENCE1515 Massachusetts Avenue, N.W., Washington 5, D. C.

ScrF,NcF,, Vol. 119is

~~~~~~~~~~~~~~~~~~~0 o:0̂ 0

in

x cancer detection

The value of the Papanicolaou techniquelies not only in early diagnosis of cervical and uterine cancer, but as acriterion against which newer experimental methods may be tested.Mellors, Keane and Papanicolaou, selecting their materilal accordi'ng toPapanicolaou's staining method and morphological analysis found asignifi'cant increase in the nucleic acid content of squamous cancer cellnuclei over normal nuclei.Mellors, R. C.; Keane, J. F., Jr., and Papanicolaou, G. N.: Nucleic Acid Content of the Squamous Cancer Cell, Science116:265 (Sept. 12) 1952.

Ortho's Papanicolaou staining preparations give the sharp nuclear andcytoplasmic definition required for accurate cytologilc diagnosis.

~~~~~ORTHOO offers the following Papanicolaou stains:EA 50, 100 cc. and 450 cc. bottlesEA 65, 100 cc. bottlesOG 6, 100 cc. and 450 cc. bottlesHarris Hematoxylin (Ortho modification) 100 cc. and 473 cc. bottlesVaginal Pipettes and Aspirator Bulbs.

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Patented Autofocus Changer feeds slideson one side, ejec them aitomatically fromthe other. All slides are automaticaflv fo-cused without readjusting.Front rotates 3600

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