This is a close-up view of a rack of microslidesundergoing staining on the Autotechnicon. Theprocess is completely automatic, and geared tosplit-second timing. The slides are now descend-ing into one staining-fluid beaker: at the precisemoment when the required immersion period hasbeen completed, they will be promptly raised,and rapidly shifted to the next station in thesequence . . . automatically, infallibly. Duringimmersion the slides are rotated gently within thefluid, thus assuring rapid, even stain permeation.

Any technique prescribed by the pathologistmay be employed. Once the master dial has beenset for the correct time intervals, the method maybe repeated time after time, without the minutestvariation, and independent of any supervision.Each batch of slides put through is stainedin exactly the same way, resulting in unvaryinguniformity.Autotechnicon staining is not only convenient,

dependable, time-saving ... it produces "Sunday-best" slides . . every day.

Trode Mork Registered U S Patent Off

automatk tissue processing... fixation,dehydration, infiltration, washing, staining

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These pumps are designed and built for those requiring the utmost in accuracyand dependability in the metering of small volumes of liquid. They providefor precision control in the dispensing of hot or cold viscous or non-viscousliquids such as soaps, oils, perfume, liquid fat, wax, glue, beverages, fruitjuices and numerous chemicals. And they have been found equally valuablefor the control of biological fluids and other sterile solutions.

The flow of the Maisch Pump is continuous, smooth and non-pulsating.Variable speed is instantly adjustable to the exact amount desired fromzerojml sec to the maximum capacity of the pump. The simple design permitseasy disassembly for cleaning and sterilizing.

Materials used in Maisch Pumps are non-pyrogenic and remain sterilewhile dispensing sterile liquids. They resist corrosion and chemical reactionof most liquids and do not contaminate or otherwise affect the quality andflavor of beverages.

Maisch Pumps are available in a wide variety of types and capacitiesranging from zero to 4.8 gallons per minute. Write today for completedetails and prices.

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These signals find the way Wl°OiOeOffJ e U | |~~~~~D DDD«| D D!D DDO

When you dial a telephone number, high-speed switchingmechanisms select your party and connect you. Through a newdevelopment of Bell Telephone Laboratories, similar mecha-nisms do a similar job in private wire teletypewriter systemswhich America's businesses lease from the telephone company.

Company X, for example, operates an air transportation busi-ness with offices all over America. At one office, an operator

DING wishes to send a message, let us say, to Kansas City. Ahead ofthe message, she types the code letters "KC". The lettersbecome electric signals which guide the message to its destination.

Any or all stations in a network, or any combination of sta-tions, can be selected. Switching centers may handle 50 ormore messages a minute...some users send 30,000 messagesa day. Delivery time is a few minutes.

IVING Defense manufacturers, automobile makers, airlines andmany other American businesses are benefiting by the speed andaccuracy of the new equipment-another example of how tech-niques developed by the Laboratories for telephone use con-tribute to other Bell System services as well.

4 BBELL TELEPHONE LABORATORIESImproving telephone service for America providescareers for creative men in scientific and technical fields.

SENC

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RESEARCHBIOCHEMICALS &

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CAN CER tesujcofoutstanding A A. A. S. Symposium Volumes:MAMMARY TUMORS IN MICE, 1945:10' contributors, viii + 223 pages, 7Y2 x lOy2, cloth-bound, doublc column, illustrated, $3.50. Cash orderprice to A.A.A.S. members, $3.00. Coordinated knowledgeof cancer of the breast in mice. It cannot fail to stimulateinterest and further research efforts in one of our mostfascinating and important biological problems. Preparedby members of the staff of the National Cancer Institute.

APPROACHES TO TUMOR CHEMOTHERAPY, 1947:93 contributors, x + 442 pages, 7%/2 x 10%A, clothbound,double column, illustrated, $7.75. Cash order price toA.A.A.S. members, $6.50. A progress report, addresedlargely to future workers. An important and trustworthyreference book. Planned under the auspices of NationalCancer Institute, Memorial Hospital of New York, Sloan-

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TO: AAAS PUBLICATIONS1515 Mass. Ave., N.W., Washington 5, D. C.

Enclosed is $ .. .. Please accept my order forO MAMMARY TUMORS in MICEO APPROACHES to TUMOR CHEMOTHERAPY

SCIENCE, Vol. 1174

" -Iafor the

instruments- ~~recording

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Phonocardiogramof DIAGNOSTIC quality

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ElectrocardiogramWITH

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Equipped with oneECG amplifier and

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2.5, 50 and 5, 100 and 10 mm/sec.5 inch recording Permapaper.

CAMBRIDGE 39,CompanyMASSACHUSETTS

January 2, 1953

Sanborn

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ELECTROPHORESIS-SCHLIEREN APPARATUS

Both models of Aminco Electrophoresis Apparatus constitutecomplete electrophoresis laboratories in single, compact units.They incorporate precise schlieren optics in an air-conditioned -space, automatic integral refrigeration system, built-in line-voltage-regulated and current-stabilized high-voltage power

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SCIENCE, Vol. 117

Uniform Results

CF RATS* For years CF RATS have been used with out-standing success in a wide range of research. . . a fact well evidenced by the continuallyincreasing demand for them.

* Should your work require the use of ratswe urge that you consider the proven depend-ability and versatility of CF RATS.

* For further information please write:

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16

What GENERAL ELECTRIC People Are SayingE. DALE TROUTJOHN VLACHX-Ray DepartmentNEW TOOL FOR MEDICAL RESEARCH: Com-pletion of the Cobalt-60 irradiator marks thebeginning of an era which medical re-searchers look, hopefully toward.

Pile-produced isotopes for teletherapv must,among other things, emit gamma radiation andhave a half-life longer than 150 days. Radio-active Cobalt-60 emits gamma radiation, hasa half-life of 5.3 years, and is obtained fromthe waste by-products of plutonium pro-duction. A 1000-curie Cobalt-60 source shouldproduce a radiation intensity about equal to1500 grams of radium.

Availability and cost of the source will gen-erally determine the future of Cobalt-60teletherapy. Until it becomes available at muchlower cost, or another artificial source is ac-cessible, the super-voltage x-ray machine willnot be supplanted by artificial radioactivesources.

General Electric ReviewNovember, 1952

*

R. BLOUNTLamp DivisionELIMINATION OF TV CAMERA LIMITATIONS:TV pictures with three-dimensional qualitiesare within reach of TV engineers today. Witliproper lighting methods and equipment thisgoal is immediately obtainable.The following methods will help in obtaining

required brightness differences: 1) providing100 vertical foot-candles of base light; 2) de-veloping form b,y applying modeling light 30to 50 per cent greater than base light; 3)separating actors from the background byapplying backlight 50 to 100 per cent greaterthan the base light; and 4) adjusting back-ground brightness with respect to foregroundsubjects.

Television Studio ClinicCleveland, Ohio

H. A. WINNEEngineeringTHE ATOMIC-ELECTRIC POWER INDUSTRY: It isunfortunate that our entry into the atomicenergy era was by way of the atomic bomb-and when I say that I am not thinking at allof the use of the bomb. It seems to me that wemay have entered the development path atthe wrong end.Most people undoubtedly feel that atomic

energy development is so vastly expensivethat it would not have come about unlessgovernment undertook it.We certainly would not have had the atomic

bomb, at the present time, nor submarineatomic power plants scheduled for the nearfuture, without government financing, but Iam not at all sure that we shall have a soundatomic-electric power industry sooner than wewould have had if this development had takena more normal course in the interested privateindustries.

Various studies now under way contemplatethe possible construction of atomic-electricpower plants, designed to produce plutonium,with electric power as more or less of a by-product.

This situation would not constitute a soundbasis for an atomic-electric power industry.Certainly, barring war, at some time in thefuture our atomic bomb stockpile should reachan adequately high peak, and the governmentwould not then be justified in continuing topurchase the plutonium output.

Atomic-electric power will- be really eco-nomically sound only when it can compete withconventional electric power without requiringa government-supported weapons market.It could not do that today-unless in somevery peculiar and unusual circumstances-nor, in my opinion, for a good many years tocome.

AIEE Machine Tool ConferenceAlbany, New York

G E N E RA L a ELECTRIC

January 2, 1953 7

* IN VISUAL RESEARCH MICROSCOPYComplete line, with widest choice of superb apochromatic objectivesfor general and highly specialized studies. Slow-motion, low-.position fine focusing adjustment; permanently aligned nosepiece;inclined parallel eyepieces, for strain-free observation.Adaptable to phase contrast, dark field and polarized light.Exclusive variable intensity Panfocal Illuminator, optional.

* IN ALL MONOCULARAPPLICATIONSQuickly interchangeable monoculartube adapts instrument for

* photomicrography, measuring,micro-projection, etc. widest rangeof accessories, for maximum use.

SCIENCE, Vol. 117