ACrIONA'flONvRO8LEMS?here's help for you..*THIS tireless servant in your laboratory will automatically

collect any number (up to 200) of rigidly controlled samplesof predetermined fluid volumes. Each collected sample maycomprise any number of drops from one to four hundred. Aseach separate sampling is completed, the carriage automat-ically advances to repeat identical collections consecutivelyuntil the whole fractionation has been made.

All you have to do is to set it up for the conditions of thechosen experiment, short or long, and then leave it alone.The machine will plod along without attention hour after hour,all day (and night) long. When the job's done, it will shutitself off,

The Technicon Fraction Collector has been thoroughlytested in actual laboratory installations, where it has proveninvaluable to busy reseorch staffs. We shall be happy to sendyou details.

Ref. Chromatography of Amino Acids on Starch Columns-W. H. Stein and S. Moore, Jrnl. Biol. Chem. 176, 337,(1948)

saves time and laborrelieves laboratory staff of the fretful and time-consuming chore of fraction-cutting: releases workersfor other duties.

triples work outputyou can run It twenty-four hours a day, continuously,to triple fractionation output as compared with an 8hour laboratory day.

gives greater resolutionby collecting a large number of small fractions,rather than a few gross ones, you'll get more datafrom a given fractionation, e.g. a chromatogram, ora fractional distillation.

& aseswes accuracybecause the possibility of human error Is automati-cally ruled out. Now fraction-collection becomes astraightforward mechanical procedure.

tECiIliCOM CWOMAOGAPit CO.y215 IEast 149th Street,tNeW York 51i N. '.

automatic

fractioncollector

Send mie detailed 1nfornction n C ltoron the echlc, .............

-.

Nan e- -'''''''',,,,,,....---.-.Addt*SSO" - - - -- .....State- ''

........ .

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In the famous Quiet Room at Bell Laboratories, this young volunteer records speech for analysis. Scientists seek to isolate the frequenciesand intensities which give meaning to words ... stripping away non-essential parts of word sounds to get the basic "skeleton" of speech.

A child or an adult . . . a man or a woman... an American or an Englishman - all speaka certain word. Their voices differ greatly. Yetlisteners understand the word at once. Whatare the common factors in speech which conveythis information to the hearer's brain?

Bell scientists are searching for the key.Once discovered, it could lead to new electricalsystems obedient in new ways to the spokenword, saving time and money in telephony.

Chief tool in the research is the sound spec-trograph which Bell Telephone Laboratoriesdeveloped to make speech visible. Many kindsof persons record their voices, each trying toduplicate an electrically produced "model"sound. While their voice patterns are studied,a parallel investigation is made of the wayhuman vocal cords, mouth, nose and throatproduce speech

Thus, scientists at Bell Laboratories digdeeply into the fundamentals of the way peopletalk, so that tomorrow's telephone system maycarry your voice still more efficiently- offeringmore value, keeping the cost low.

5-4-

-oE 3-

0 2-Q1

.4

-3

-2

time U.6 seconds

Spectrograms of young girl's voice (right) and man's voice making "uh"sound as in "up." Horizontal bars reveal frequencies in the vocal cavitiesat which energy is concentrated. The top of the picture is 6000 cycles persecond. Pictures show how child's resonance bars are pitched higherthan man's.

BELL TELEPHONE LABORATORIESImproving telephone service for America provides careersfor creative men in scientific and technical fields.

Analyzing air brakes

for faster stops

How LONG does it take pressure to build up to required levels atthe brake chambers after the driver applies the brake pedal? Toanswer this all-important question of "air-transmission" time,Bendix-Westinghouse Automotive Air Brake Company as-sembles on a test stand a complete counterpart of the brakesystem which is to be installed in a truck, truck-tractor, or bus.All components and air lines are the same as those to be usedon the vehicle.

Pressure pickups are used at various critical points in thesystem, and a mechanical foot is used to depress the brake pedal.A Consolidated Recording Oscillograph records the time thatthe pedal starts downward and the rate at which pressure buildsup at the brake chambers. At maximum pressure, the brakepedal is released and the rate of pressure drop recorded. A fullreport on the air-transmission time of the system based on thisaccurate analysis is furnished the vehicle manufacturer.

I I

III

LLL

Consolidated EngineeringCORPORATION

300 North Sierra Madre Villa, Pasadena 8, California

Sales and Service through CEC INSTRUMENTS, INc.,

.a subsidiary with offices in: Pasadena, New York, Chicago,Washingtoni D. C., Philadelphia, Dayton.

U..Dynamic Recording Systems... like the one shown here are designed and manu-factured by Consolidated. Variations in the arrangementof the equipment are infinite. Applications are widelyvaried throughout industry and the sciences. A typicalrecording system includes pickups, amplifiers or bridgebalances, and a recording oscillograph. Write for Bulle-tin CEC 1500B.

Simple, RapidNa and K Analysesby Flame PhotometryNa and K analyses in a few minutes and ac-

curate to within 1 or 2 per cent, are standardprocedure with the new, improved Perkin-ElmerModel 52-C Flame Photometer. Not an attach-ment, but a separate, complete instrument, thePerkin-Elmer Flame Photometer operates bymeans of either direct intensity or internal stan-dard methods. Analyses are readily made on

blood, food, water, or any substance placed insolution. Operation is simple and dependable;results, reproducible.

The Perkin-Elmer Flame Photometer oper-

ates wherever electricity, compressed air, andpropane or acetylene fuel are available. Its pre-

cision electronic circuits are more rugged anddependable than delicate galvanometers. Fivecc of fluid, including dilution, is needed per

determination; one cc of serum is sufficient forthree determinations of both Na and K afterdilution.

Write for complete details

THE PERKIN-ELMER CORPORATIONNORWALK, CONN.

Leading manufacturers of Infrared Spectrometers, Con-tinuous Infrared Analyzer. Universal Monochromator,Flame Photometer. Tiselius Electrophoresis Apparatus,D. C. Amplifier, and other electro-optical instruments

for analysis and reserch.

G.A.B. Interference Filters(Made in Switzerland)

for isolating narrow spectral, bands

3-

2s0at H.

400 450 500 550 6W 65U 7W00WVE LEN£H mp

Spectral Range: 400-900 millimicronsSpectral Widtk- 2-15 mR, Transm.: 45-50%

Size: 2" x 2". Other sizes on order.ForFlame Photometry and Color Densitometry

Microscopy and PhotomicrographyColorimetry and Fluorimetry

also In reflectometry, light scattering measurements,microcolorimetry, refractometry, polarimetry, and in allother fields requiring monochromatic light In the visibleand near-infrared range.

Write for Bulletin #180 to

PHOTOVOLT CORP.95 Madison Ave. New York 16, N. Y.

SCIENCE, Vol. 111I4

~water flow ana increases-! condensing efficiency.

$';a'3~~~~~~~~~~~5Z ~~~~& 4 ~~~Hand -tooled outlets -onsome side for convenience.

YOUR

BUDGET PYREX brand ReagentBottles-5Permainemt redglass labels for quick easy

Whether you are teaching chemistry or eading. IterHageeasy grip stoppers. Highrunning a business, costs are mounting. chemical stability for pro-They must be watched more carefully tection of standard solu-

tion. Special labels avail-than ever. You definitely can make able without mold charge.economy part of your teaching programby standardizing on PYREX brand lab-oratory ware.

Experience over a long period oftime points to the fact that PYREXbrand laboratory apparatus stands uplonger under student abuse than anyother brand. Its low coefficient of ex-pansion minimizes loss from thermalshock. Its chemical formula is such that PYREX brand Teit remains stable under heat and acids. Tubes-PovedbcIts over-all design provides exceptional the most serviceablephysical strength. You can stretch your can buy. Made from F

.cision tubing, careftlaboratory ware budget farthest by al- annealed for strengways asking your laboratory dealer for Available with andwiPYREX brand. o r

CORNING GLASS WORKS, CORNING, N. Y.

c.~?ae44fe4r4(4eef4r

VISIT THE NEW CORNING GLASS CENTER

July 18, 1952 _5

onu n

proportionalcounters

by

= A=

riMz. MOJDEL rc.3

Total instrumental error is less than0.5%; the character of the "CandidDecade".scaling circuit guarantees thatscaling errors will not participate. Nogeometry or window error exists. Reso.lution loss 1% per 100,000 c/m.

The yield runs typically 5 to 50 timeshigher than an end-window GM counter.

Beta background runs less than 2 c/mper cm' of counting area; Alpha back.ground is less than 0.1 c/m.

m- Built-in automatic features reduce theoperating cycle to 4 rapid operations.

Less than 10 minutes is required to de-contaminate, clean and reassemble thecounting chamber.

Designed specifically for ProportionalCounting with the least possible com-promise.

The instrument counts Alphas, Betas andGammas. Alphas are counted with com-plete discrimination from high intensityBeta activity. Betas are counted in thepresence of Alpha activity.

You can depend on Instrumentsby Nuclear Measurements whenyou need Instruments forRAIICIOIEMISRY MINERAL ASSAY

tAIUIOLOUY WATER & SEWAGE ASSAY

RADIOTHERAPY NUCLEAR PYSICSHELTH PHYSICS MINERAL SUECH

Contact NM C First. . . For The Finest

2450 N. ARLINGTON * CH. 2415 * INDIANAPOLIS, INDIANA

RESEARCH

BIOCHEMICALS* ~~~ForINVESTIGATIONAL USE

AMINO ACIDSA complete selection of more than 90

amino acids of maximum purity including:DL ALPHA ALANINEBETA ALANINEL AL-ANINEDL ALPHA AMINO-n-BIJTYRIC ACIDL ARGININE (HCI, Free Base)ASPABAGINE (L, DL, D)ASPABTIC ACID (L, DL, D)BETAINEDL CITRULLINECBEATINECREATININECYSTEINE (HCI, Free Base)CYSTINE (L, DL)DL DOPADJENKOLIC ACIDDL ETHIONINEGLIJTAMIC ACID (L, DL, HCI)GLUTAMINEGLYCYL GLYCINEHISTIDINE (L, DL, D)DL HOMOCYSTEINEDL HOMOCYSTINEHYDROXY-L-PROLINEISOLEUCINE (L, DL, D)LBUCINE (L, DL, D)LYSINE HCI (L, DL)METHIONINE (L, DL, D)METHIONINE SU1LFOXIDEDL NOBLEUCINEDL NORVALINEORNITHINE HCI (DL, L)PHENYLALANINE (L, DL, D)PROLINE (L, DL)SARCOSINEDL SERINEB PHENYL SERINETAURINETHREONINE (L, DL, D)DL ALLO THREONINETRYPTOPHANE (L, DL, D)TYROSINE (L, DL)VALINE (L, DL, D)

ALSO-A SELECTION OF 20 PEPTIDES

WRITE FOR

NEW

CATALOGUE

#S 975

Listing over 600Research Biochemicals

SCIENCE, Vol. 116

l1 MALIWAUL

.U~uZaU~EEVEE~IIa ii1

-I-

-.

I

I

^ * ^ - -

M Aft d%

4NN NOUU N C I N GThe New Line of

PAPER PARTITION

CHROMATOGRAPHYE QU I PM E N T

For the rapidly growing field of paper partition chromatographyresearch we offer a more complete line of chromatographic cabinets,drying ovens, and accessory equipment, especially designed for theparticular requirements of this new chromatographic method.

THE NEWLY DESIGNED CHROMATOCABBoth Models A300 and B275 are now offered with hinged top

.....and convenient bottom drawer. Model A300 is fully insulated toinsure constant temperature conditions during the period ofoperation. Both models with interior lining of stainless steeland screw type legs for leveling.

DRYING OVEN FOR CHROMATOGRAMSA mechanical convection oven designed specifically for heatingpaper chromatograms, offering the following features:1. Controlled temperature over a wide range.2. Continuous circulation of heated air. Both heat and air circula-

tion controlled according to requirements.3. Heater and air blower operate independently, permitting air

circulation without heat if desired. .R4. Sliding rack permnits easy handling of chromatograms without

transference from original anti-siphon rods. Each chromatogramcan be added or removed from the oven without moving orhandling other chromatograms on the rack.

RACKS AND 5SOLVENT ASSEMBLIESEither Pyrex glass or ALSO AVAILABLE:stainless steel racks and

-- l R solvent assemblies for * Pyrex Solvent Troughs * Pyrex Disc Chambersone dimensional separa- CSailes * Micro Pipettes

tions. Pyrex chromatog- * Densitometers . . . for * Stainless Steel Chromatog-raphy jars and the neces- quantitative determinations raphy Clipssary solvent assemblies on paper * Pyrex Aspirators for Spray-are Included with the * Ultraviolet Lamps ing Indicatorsracks, or sold separately.

g u 1 g g . . ~~~~~~~~~~WriteFor Brochure and Prices

RESEARCH EQUIPME'NT CORPORATION-~A N U F A C T UN~R E R S

~..-~4~ 44~41 113 5 T H IRD ST-R E,ET, OAKLAND 20, -CAL IF.~~~~~ ~~~~~~~4~~~~~~~~~~~4; ~~~~~~~~~Dept. S

July '18, 1952 7

he PRODUCTION LINE!

Sueed Readigs. ... from ALL NEW DE-SIGnt Want analyses in 10 seconds? 15 seconds?

an have the speed your process requires.N ore losses of time, materials and money due to~sow readings! This new Bausch & Lomb Indus-trial Refractometer is strictly a production instru-ment ... designed and built for use right besideyour vats. You'll want several ... at least one foreach testing area.* Super Speed Loading ... new prism design.* Super Speed Cleaning ... prisms easily, quicklycleaned. Prevents contamination of new samples.Internal parts protected from dirt, fumes, strayliquids.* Super Temperature Stability... easier to main-tain stable temperatures.

New Bausch & Lomb

REFRACTOMETER

9flhrt* dependable, uniform accuracy of+.0001. Simplified to basic essentials . . . oper-ated by any average worker. Scales "tailor-made"to seven specific ranges industry requires.

BAUSCH & LOMB OPTICAL COMPANY

624-27 ST. PAUL STREET, ROCHESTER 2, NEW YORK

Please send me complete information on the NewBausch & Lomb Industrial Refractometer.

NAMEI TITLE* COMPANY* STREET I* CITY ZONE STATE_ _L m m___ m - __ __- _m m - J

SCIENCE, Vol. 116