2 August 1957, Volume 126, Number 3266

AMERICAN ASSOCIATIONFOR THE

ADVANCEMENT OF SCIENCE

Board of DirectorsLAURENCEH. SNYER, PresidentrtidWALLAcE R. BRODE, President ElectPAUL B. SEARS, Retiring President SincePAUL M. GROSS on the raGEORGE R. HARRISON markedPAUL E. KLOPSTEmCHAUNCEY D. LIAzE correspoiMARGARET MEAD necessaryTHOMAS PARK DurinlWILLIAM W. RUBEY tory at tlALAN T. WATERMAN occupiedPAUL A. SCHERER, Treasurer ScienDAo WOLFLE, Executive Officer Science

matter, .DARL WOLFLE, Executive Officer the first

GRAHAM DUSHANE, Editor similar pCHARLOTTE V. MEETINo, Associate Editor sity was

JOSEPH TURNER, Assistant Editor SubsecEditorial Board were est:

WALLACE R. BRODE EDWIN M. LERNERBENTLEY GLADs WILLIAM L. STRAUS, JR. come to

KARLLARK-HoRovrrz EDWARD L. TATUMof choic

Editorial Staff laboratoiPATRICIA L. CARSON, MARY L. CRABILL, HARRY appearecDAVID, SARAH S. DEES, NANCY S. HAMILTON, Yale, 2;OLIVER W. HEATWOLE, YuKIE KozAI, ELLEN E. MichigaiMURPHY, ROBERT V. ORMES, BET8sABE PEDERSEN,LaboratcMADELINE SCHNEIDER, JANE STINE, JACQUELYN laboratVOLLMER laborato

EAaRL J. SCHERAGO, Advertising Representative holm, Y

will sooJSCIENCE, founded in 1880, is published each It s c

Friday by the American Association for the Ad- Ivancement of Science at Business Press, Lancaster, field maPa. Entered at the Lancaster, Pa., Post Office as

second class matter under the Act of 3 March 1879. articlesSCIENCE is indexed in the Reader's Guide to in comp

Periodical Literature and in the Industrial Arts to establIndex.

Editorial and personnel-placement correspond- with raence should be addressed to SCIENCE, 1515 for us toMassachusetts Ave., NW, Washington 5, D.C.Manuscripts should be typed with double spacing pand submitted in duplicate. The AAAS assumes no the Auxresponsibility for the safety of manuscripts or forthe opinions expressed by contributors. For detailed tute persuggestions on the preparation of manuscripts, book Radicreviews, and illustrations, see Science 123, 16 (4 publisheJan. 1957).

Display-advertising correspondence should be reportsaddressed to SCIENCE, Room 740, 11 West 42 of the d.St., New York 36, N.Y.

be permChange of address notification should be sent to be pern

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MONTHLY.

SCIENCE

les on Radiocarbon --Dating1947 Science has played a large part in the publication of articlesadiocarbon method of dating organic remains. However, the recent

increase in the number of laboratories at work in this field and theriding increase in the number of radiocarbon lists has made ity for the Editorial Board to reconsider its publication policy.g the years immediately after 1947 the radiocarbon dating labora-he University of Chicago, under the direction of Willard F. Libby,ithe field alone. The Chicago group published several papers inon cosmic radiation and radiocarbon, on radioactivity of livingand on the radiocarbon method of estimating age, and, in 1951,extensive list of radiocarbon dates. In the same year the first

paper from the newly established laboratory at Columbia Univer-

published in Science.quently, several additional laboratories for radiocarbon datingablished in this country and in Europe. Inasmuch as Science hadbe regarded as the archival journal in this field, it was the journal,e for publication of almost all of the results from the various

tries. From 1951 through 1956, 18 articles on radiocarbon datingd in Science: from the Chicago group, 5 articles; Columbia, 3;Copenhagen, 2; U.S. Geological Survey, 3; Pennsylvania, 2; and

Ln, 1. So far in 1957 two articles from the Humble Oil Companyories have been published, and the first article from the Heidelberg)ry appears in this issue. Articles from Columbia, Groningen, Stock-

fale, and Arizona await publication. The U.S. Geological Surveyn submit its fourth list.lear to the board that the increase in the number of papers in this

akes it impossible for Science to continue to publish radiocarbon

in full. Perhaps the best solution-and indeed the usual solution

arable specialized fields in the past-would be for those interested

lish their own journal. Nevertheless, in view of our close association

diocarbon dating, the board sought some way to make it possibleZ continue to serve as a medium for the publication of radiocarbon

if those concerned wished to take advantage of it. The existence of

iliary Publications Project of the American Documentation Insti-

rmits an alternate solution.Dcarbon lists received on or after 1 October 1957 will no longer beed in full as lead articles, but will, if acceptable, be published as

without dating lists. These reports will serve to describe the scope

[ating done and will provide a citation to the dating lists, which will

ianently stored in the American Documentation Institute, Auxiliarytions Program, the Library of Congress. Each report will carry a

that will give details about how photocopies of the lists may be

d. -This form of publication will make the radiocarbon dates per-

ly available to all who are interested and will make it possible for

to continue to play an important part in making known th-e.resultsocarbon dating-results that are of interest to scientists in fields as

as archeology, geology, and prehistory.-G. DuS.

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annual, Woods Hole, Mass. (A. M.Shanes, NIH, Bethesda 14, Md.)

4-6. Latency and Masking in Viral andRickettsial Infections, symp., Madison,Wis. (A. S. Evans, Div. of PreventiveMedicine, Univ. of Wisconsin MedicalSchool, Madison 6.)

4-6. Magnetic Amplifiers, technicalconf., Pittsburgh, Pa. (G. F. Pittman, Jr.,Westinghouse Electric Corp., P. 0. Box10596, Pittsburgh 35.)

4-7. American Soc. for Pharmacologyand Experimental Therapeutics, Balti-more, Md. (P. K. Smith, George Wash-ington Univ. School of Medicine, Wash-ington 5.)

4-11. British Assoc. for the Advance-

ment of Science, 119th annual, Dublin,Ireland. (Secretary, BAAS, BurlingtonHouse, London, W.1, England.)

5-7. American Physical Soc., Boulder,Colo. (W. A. Nierenberg, Univ. of Cali-fornia, Berkeley 4.)

5-7. American Political Science Assoc.,natl., New York, N.Y. (E. M. Kirkpatrick,APSA, 1726 Massachusetts Ave., NW,Washington 6.)

6-12. Medicine and Social Hygiene, in-ternatl. symp., Trieste. (M. Lovenati, viaCavana 18, Trieste.)

7-14. Odontostomatology, 12th inter-natl. cong., Rome, Italy. (G. Corradi, 16via Boezio, Rome.)

7-14. Sociology, 17th internatl. cong.,

New dual-purposeLaboratory Autoclave

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Beirut, Lebanon. (G. Gini, via Adige 39,Rome, Italy.)

8-12. International College of Sur-geons, 22nd annual, Chicago, Ill. (K. A.Meyer, ICS, 1516 Lake Shore Dr., Chi-cago 10.)

8-13. American Assoc. of ClinicalChemists, annual, New York, N.Y. (M.M. Friedman, Lebanon Hospital, NewYork 57.)

8-13. American Chemical Soc., NewYork, N.Y. (A. H. Emery, ACS, 1155 16St., NW, Washington 6.)

8-13. Nuclear Structure, internatl.conf. (IUPAP), Rehovoth, Israel. (A. deShalit, Weizmann Inst. of Science, Re-hovoth.)

8-15. International Cong. of Crop Pro-tection, 4th, Hamburg, Germany. (Bio-logische Bundesanstalt fur Land- undForstwirtschaft, Messeweg 11-12, Braun-schweig, Germany.)

9-11. Electron Microscope Soc. ofAmerica, annual, Cambridge, Mass. (D.M. Teague, Chrysler Corp., Box 1118,Detroit 31, Mich.)

9-11. Quantitative Methods of Mam-malian Cell Culture, 2nd annual, Denver,Colo. (Office of Graduate and Postgradu-ate Education, Univ. of Colorado MedicalCenter, Denver 20.)

9-13. Illuminating Engineering Soc.,annual, Atlanta, Ga. (A. D. Hinckley,IES, 1860 Broadway, New York 23.)

9-13. Instrument Automation Conf.,12th annual, Cleveland, Ohio. (Instru-ment Soc. of America, 313 Sixth Ave.,Pittsburgh, Pa.)

9-13. Neutron Interaction with Nuclei,internatl. conf. of- IUPAP, New York.(W. W. Havens, Pupin Cyclotron Lab.,Columbia Univ., 538 W. 120 St., NewYork 27.)

9-15. Macromolecular Chemistry, inter-natl. symp., IUPAC, Prague, Czechoslo-vakia, (Secretariat, ISMC, 5, Technicki,Prague 6.)

9-20. Radio-Isotopes in Research,UNESCO conf., Paris, France. (UNESCOHouse, 19, avenue Kl1ber, Paris 166e.)

10-13. Alaskan Science Conf., 8th, An-chorage. (C. J. Beers, U.S. Coast andGeodetic Survey, College, Alaska.)

10-13. American Statistical Assoc., an-nual, Atlantic City, N.J. (D. C. Riley,ASA, 1757 K St., NW, Washington 6.)

10-13. Biometric Soc., Eastern NorthAmerican region, Atlantic City, N.J. (A.M. Dutton, Box 287, Sta. 3, Rochester,N.Y.)

10-13. Econometric Soc., Atlantic City,N.J. (R. Ruggles, Dept. of Economics,Yale Univ., New Haven, Conn.)

10-13. Institute of Mathematical Sta-tistics, annual, Atlantic City, N.J. (G. E.Nicholson, Jr., Dept. of Statistics, Univ.of North Carolina, Chapel Hill.)

14-15. Minnesota Acad. of Science,Cedar Creek Forest. (M. R. Boudrye, 51University Ave., St. Paul 3, Minn.)

15-18. American Inst. of Chemical En-gineers, natl., Baltimore, Md. (F. J. VanAntwerpen, AIChE, 25 W. 45 St., NewYork 36.)

16-21. Orthopedic Surgery andTraumatology, 7th internatl. cong., Bar-celona, Spain. (J. M. Vilardell, AvenidaJose Antonio 654, Barcelona.)

(See issue of 19 July for comprehensive list)

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EQUIPMENT NEWSThe information reported here is ob-

tained from manufacturers and fromother sources considered to be reliable.Science does not assume responsibilityfor the accuracy of the information. Allinquiries concerning items listed shouldbe addressed to Science, Room 740, 11W. 42 St., New York 36, N.Y. Includethe name(s) of the manufacturer(s) andthe department number(s).

*QUADRUPLE-BEAM OSCILLOSCOPE is lin-

ear to ± 0.5 db from direct current to100 kcy/sec. Input may be either differ-ential or single-ended. Features includeautomatic amplitude calibration, four-step sequence timer, crystal-controlledtiming pulse, and provision for synchro-nization and control of recording cam-

eras. (Electronic Tube Corp., Dept.S462)

* LABORATORY RELAY iS transistorized toimprove reliability. Input of 12 ga willactuate the relay. A noninductive loadof 4 amp is controlled with a guaranteedlifetime of a million contacts. Up to 10amp can be handled for short periods.Any combination of normally open or

normally closed input circuits and nor-

mally on or normally off output is pro-

vided. No warm-up period is required.(Fisher Scientific Co., Dept. S463)

* AMPLIFIER is designed to furnish con-

stant voltage output at frequencies rang-

ing from 40 to 1000 cy/sec. for operationof synchronous motors requiring up to150 va at 115 v. Input may be providedby a signal generator, a tuning-fork, or

a crystal-controlled oscillator. Input im-pedance is 10,000 -ohm; gain is 56 db;and signal-to-noise ratio 54 db. (Am-plifier Corporation of America, Dept.S466)

* BLOOD-PRESSURY RECORDER employs theusual measurement procedure followedby the physician, but does so automati--cally. Measurements are made at inter-vals of from 30 sec to 1 hour. A self-contained source of air inflates anddeflates the sphygmomanometer arm cuffperiodically. A microphone and ampli-fier respond to the arterial sounds whencuff pressure corresponds to systolic anddiastolic values. The instrument can befurnished with a settable alarm. (TheColson Corp., Dept. S457)

* PULSE-HEIGHT ANALYZER can storemore than 1 million counts in each of100 channels. Linearity is better than 0.2percent. Pulse amplitude discriminationis accomplished by means of amplitude-to-time conversion with crystal-oscillatorgating. Magnetic-core memory is usedfor storage of counts. Counting loss, re-

sulting from conversion to time, is keptto a minimum by providing temporary

2nd printing July 1957

THE FUTURE OF

ARID LANDSA symposium volume of theAmerican Association for theAdvancement of Science

Edited by Gilbert F. WhiteDepartment of Geography,

University of Chicago6 x 9 inches, 464 pages, 49 illus-

trations, index, clothbound,October 1956

Price $6.75. AAAS Members' pre-paid order price $5.75

The volume presents the ef-forts of scientists from 17 coun-tries and from as many disci-plines to assess the state ofman's struggle to make produc-tive and stable use of theworld's arid lands,

It contains the papers andrecommendations of the Inter-national Arid Lands Sympo-sium and Conference, Albu-querque and Socorro, NewMexico, April and May 1955.The symposium develops

around a few basic questions.The representation and treat-ment of the subjects are highlyinterdisciplinary and lead tosome important conclusions.The breadth and scope are in-dicated by the groupings ofthe Conference recommenda-tions: Anthropology, Archaeol-ogy and Geography; Meteorol-ogy and Climatology; Hydrol-ogy, Geology and Soils; Biology,Ecology and Conservation; Or-ganization, Communication, andInterdisciplinary Programs.Workers in all -these fields, aswell as administrators of gov-ernment and private programs,will find the contents of thisvolume both stimulating forideas and invaluable as a sourceof information."An extremely useful and

stimulating assessment of thesubject."

British Agents-Bailey Bros. vSwinfen, Ltd., 46 St. Giles

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SCIENCE, VOL. 126

=

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storage for a second pulse while the firstpulse is being analyzed. Data are printedout on ten-column adding machine tape.(Pacific Electro-Nuclear Co., Dept.S489)

* CRYSTALLINE MATERIALS made fromglass provide a useful combination ofproperties. Specific gravity is less thanthat of aluminum; the materials have astrength-to-weight ratio almost equal tothat of aluminum alloy. High-frequencyand high-temperature electric propertiesare excellent. The materials, trade namedPyroceram, are formed by methods usedfor glass. (Corning Glass Works, Dept.S485)

* SPECTROPHOTOMETER, a single-wave-length, narrow-band instrument, is de-signed to measure absorbance and opticaldensity changes at 350 mit. The instru-ment, called the "Coenzometer," func-tions to measure transaminase, lactic de-hydrogenase, blood alcohol, turbidity,and pyridine nucleotides for diagnosis ofcardiac or hepatic disorder. The instru-ment operates on standard electricpower. (Macalaster Bicknell Co., Dept.S487)

* ULTRASONIC GENERATOR for therapeuticapplications features a transducer incor-porating a 10-cm2 quartz crystal. Totaldosage intensity is 30 w, with no energybeing reflected back into the hand of theoperator. The unit complies with allFCC requirements on minimum con-ducted line and radiation interference.(Dakon Tool and Machine Co., Inc..Dept. S492)

* AUTOMATIC CHART READER moves a re-corder chart at a uniform rate, sensesthe position of the inked trace, and pro-duces an output proportional to theordinate value of the trace. Output ispresented as voltage, shaft-rotation,pulse-width-modulated-carrier, and alsoin digital form. Accuracy is ± 0.1 percentof full scale. (Geotechnical Corp., Dept.S506)

ELECTRONIC GALVANOMETER is a com-

bination of d-c null detector, linear de-flection indicator, microvoltmeter, mi-cromicroammeter, and low-level d-c am-plifier. Its circuit is fully transistorizedand chopper stabilized. Seven decaderanges cover 10 [tv to 10 v or 0.001 ga to1 ma full scale. The instrument is insensi-tive to shock, vibration, or stray fields.Sensitivity as a galvanometer is 2 x 10-ilamp per division. (Kin-Tel, Dept. S491)

* SPECTRUM ANALYZER for the range 450to 550 kcy/sec has resolution ranges from3.2 kcy/sec to 10 cy/sec. Signals up to1000 Mcy/sec can be observed by meansof an external signal generator and aninternal aperiodic mixer which translate2 AUGUST 1957

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NORTHWESTERN UNIVERSITY CONFERENCEON

LIQUID SCINTILLATION COUNTING

20-22 August

Cj ~~~~~~1957Evanston,

This Conference will be sponsored jointly by the National Science Foun-dation and the Technological Institute of Northwestern University.The papers presented will cover fundamental theory and applications ofliquid scintillation counting.To receive complete program and also to receive future announcementsregarding liquid scintillation counting, send letter or card to:

Dr. Carlos G. Bell, Jr.Northwestern Technological Institute

Evanston, Illinois

a

the spectrum segment to be analyzed tothe input range of the instrument. Scanrate is adjustable in steps of 30, 5, 1,and 0.1 cy/sec. (Panoramic Radio Prod-ucts, Inc., Dept. S391)

*STAINLESS STEEL containing 1 percentboron is available in plate, sheet, strip,and bars. The boron content contributesthermal-neutron absorption properties.The material is workable hot and cold,and is weldable and machinable. (Su-perior Steel Corp., Dept. S469)

* NASOMETER measures the degree ofpatency of the nasal respiratory passages.The instrument is actuated by the pa-tient, who exhales through each nasalpassage into tubes. Two pens on a stripchart respond to the flow of air, and, ifthere are no obstructions, draw a sym-metrical pattern. (Royson Engineering,Dept. S473)

* PHASEMETER utilizing a passive systemis available in a single frequency modelbetween 60 cy/sec and 20 kcy/sec andin a three-frequency unit for any threeselected frequencies in the same range.Continuous measurement of phase anglefrom 0 to 360 deg may be obtained. Line-arity error is less than ± %2'. (StathamDevelopment Corp., Dept. S507)

M CAPACITORS are said to be stable to ± 0.1percent over a temperature range from- 20° to + 150'F. Insulation resistance isI00WMohm times capacitance in micro-farads at 250'F.'Units are hermeticallysealed in nonmagnetic tubes with com-pression glass seals. They are availablein 300-, 600,- and 1000-v ratings. (Elec-tron Products Co., Dept. S467)

* PUMP uses the principle of moving steelfingers, in a wavelike motion over flex-ible tubing, to pump liquids, gases, andslurries. Tubes of inside diameter from1/32 to Y/4 in. are accommodated. Pump-ing rate is variable from 0.1 to 250 ml/min. (Sigmamotor, Inc., Dept. S475)

* TRANSISTOR CIRCUIT SIMULATOR elimi-nates "breadboard" layout by simulatingcomplete amplifier stages. Everything re-quired for R-C amplifier circuits is builtinto the instruments, including 2- and20-gf direct coupling capacitors. Circuitresistances are variable over a widerange. Battery voltage supply for separatebias and load provides 1.5, 3, 4.5, and6 v. (Sprague Products Co., Dept. S490)

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exciter consists of a driving head, hy-draulic accumulator, high-pressure hy-draulic pump, electronically controlledservo valve, and electronic control sys-tem. (MB Manufacturing Co., Dept.S470)

* AUTOMATIC BLOOD CELL COUNTER basesits operation on differences in electricconductivity between blood cells andcommon diluents. The sample beingcounted passes through a 0.1-mm orifice.An individual cell, in passing through theorifice, raises the electric resistance ofthe orifice contents. Resulting voltagepulses, which are proportional to cellsize, are displayed on an oscilloscope andcounted by a pulse-height discriminator.Counting stops automatically when 0.5ml has passed through the orifice. Count-ing time is approximately 25 sec. (Coul-ter Electronics, Dept. S454)

* PLATINUM RESISTANCE THERMOMETERSfor temperature sensing in noncorrosiveliquids or gases achieve rapid responseby providing almost immediate contactbetween the environment and the ex-posed sensing element. The platinumwinding is protected by a stainless-steelcage. Thermal response time is less than2.5 sec in air and less than 50 msec inwater. Range of operation is from - 3200to + 750'F with accuracy better than ± 1percent of full scale and repeatability± 0.2 percent. Up to 5 v can be deliveredwithout additional amplification. (Trans-Sonics Inc., Dept. S484)

*AIR SAMPLING DEVICE is based on a mi-croventuri principle in which Freon pro-pellent is ejected through a jet nozzle toprovide pumping action. The suctionend of the aspirator is connected to astandard glass impinger assembly forother than solid particle counts. For dustsampling, a standard Millipore filter at-tachment is substituted for the glass im-pinger. (Union Industrial EquipmentCorp., Dept. S472)

* OHMMETER is designed to measure lowresistance. Readings are obtained from0.1 to 25 ohm, in two ranges, with accu-racy of ±3 percent of full scale. Maxi-mum circuit current is 5 ma. One 1.5-vbattery furnishes power to the meter.(Simpson Electric Co., Dept. S483)

*PORTABLE RECORDING MILLIVOLTMETERis designed for electrolysis surveys. Move-ment sensitivities of either 2000 or10,000 ohm/v can be furnished. Recordis made on an 8-in. diameter, carbon-coated chart. The writing stylus is vibra-tor-actuated so that drag is avoided. Therecorder is weatherproof and can be leftunattended for up to 1 week. (BristolCo., Dept. S509)

JOSHUA STERNNational Bureau of Standards

SCIENCE, VOL. 126

6592 HAMILTON AVENUE * PITTSBL