20 June 1958, Volume 127, Number 3312

AMERICAN ASSOCIATIONFOR THE

ADVANCEMENT OF SCIENCE

Board of Directors

WALLACE R.. BRODE, PresidentPAUL E. KLOPSTEG, President ElectLAURENCE H. SNmDERs Retiring PresidentPAUL M. GROSSGEORGE R. HARRISONCHAUNCEY D. LEAKEMARGARET MEADTHOMAS PARKMINA REESWILLIAM W. RUBEYALAN T. WATERMANPAUL A. SCHERER, TreasurerDAEL WOLFLE, Executive Officer

DAEL WOLFLE, Executive OfficerGRAHAM DUSHANE, Editor

JOSEPH TURNER, Assistant EditorROBERT V. ORMES, Assistant Editor

Editorial BoardWALLACE R. BRODE EDWIN M. LERNEEBENTLEY GLASS WILLIAM L. STRAUS, JR.

EDWARD L. TATUM

Editorial StaffSARAH S. DEES, LUCILLE GUINARD, NANCY SHAMILTON, OLIVER W. HEATWOLE, NANCY L.JACKSON, YUKIE KOZAI, ELLEN E. MURPHY,BETHSABE PEDERSEN, MADELINE SCHNEIDER, JAC-QUELYN VOLLMER, MARIA A. WOLSAK

EARL J. SCHERAGO, Advertising Representative

SCIENCE, which is now combined with THESCIENTIFIC MONTHLY, is published each Fri-day by the American Association for the Advance-ment of Science at Business Press, Lancaster, Pa.The joint journal is published in the SCIENCEformat. Entered at the Lancaster, Pa., Post Officeas second class matter under the Act of 3 March1879. SCIENCE is indexed in the Reader's Guideto Periodical Literature.

Editorial and personnel-placement correspond-ence should be addressed to SCIENCE, 1515Massachusetts Ave., NW, Washington 5, D.C.Manuscripts should be typed with double spacingand submitted in duplicate. The AAAS assumes noresponsibility for the safety of manuscripts or forthe opinions expressed by contributors. For de-tailed suggestions on the preparation of manu-scripts, book reviews, and illustrations, see Science125, 16 (4 Jan. 1957).Display-advertising correspondence should be

addressed to SCIENCE, Room 740, 11 West 42St., New York 36, N.Y.Change of address notification should be sent to

1515 Massachusetts Ave., NW, Washington 5, D.C.,4 weeks in advance. If possible, furnish an addressstencil label from a recent issue. Be sure to giveboth old and new addresses, including zone num-bers, if any.Annual %ubscriptions: $8.50, foreign postage,

$1.50; Canadian postage, 75¢. Single copies, 35¢.Cable address: Advancesci, Washington.

SCIENCE

Members x 2Professors sometimes remark that the university would be an ideal place

if it were not for the students. But no one ever makes such quips about anassociation. They may complain about the officers, or the policies, the pub-lications, or the meetings; they may dislike some of their fellow members;but everyone agrees that an association is the members who comprise it.Within rough limits, the rate of growth of membership is a function of theusefulness of the association, and, again within rough limits, an increase inmembership allows the association to be of greater service to its member-ship, for the cost of operation increases less rapidly than does the numberof members.AAAS membership has shown marked growth since its founding 110 years

ago, and had a big spurt in the years surrounding the centennial celebrationin 1948. A well organized membership drive increased the total from 29,000in 1946 to 45,000 in 1949. Then came a slack period; from 1950 through1954 the annual increases were small, and totaled only 4000 in the five-yearperiod. Since 1954, however, there has been an upturn, with a gain of 7000in the past three years.The Board of Directors has decided that a substantial further increase

is in the interest of all members and that this year, when the Associationcompletes its 110th year, is a good time to make a special effort to increasethe membership. Accordingly, each member was recently mailed a letterrequesting him to invite one or more of his nonmember colleagues to jointhe Association. The every-member-get-another-member idea is more thana membership-drive gimmick; scientists who are already members are thebest judges of who among their colleagues would find AAAS membershipmost profitable, and experience shows that their nominees are likely to join.The members of any association must decide what the admission re-

quirements will be. Some societies set quite specific requirements in termsof education or experience; others welcome anyone who is sincerely inter-ested in the association's objectives and activities. The AAAS followed theBritish Association in adopting the latter policy. Thus anyone who is sin-cerely interested in the advancement of science and who wishes to receiveScience is eligible for membership.

There are, of course, other reasons than the receipt of Science for joiningthe AAAS, yet that is the most frequent and tangible advantage of mem-bership. It is an advantage that is also enjoyed by a considerable numberof nonmembers, for sample surveys of readers have consistently shown thatthe number of readers is about twice as large as the number of subscribers.These nonmember readers are a good potential source of additional mem-bers, for their active interest in one aspect of the Association's program hasalready been demonstrated.The letter that the Board of Directors sent to all members not only in-

vited each to nominate a new member but also urged him to encouragehis nominee to accept the invitation to join. Early returns indicate a largeresponse, but there are still many members to be heard from. This editorialis a reminder that the invitation was seriously meant; we hope that themembers will nominate a very substantial number of new members. Thiseditorial is also an invitation to readers who are not members. An appli-cation form is printed on page 1450. Nonmembers who are interested inthe objectives and activities of the AAAS are invited to use it.-D.W.

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MeetingsStatistics and Probability

During the week of 2-8 March, an in-ternational conference on statistics andprobability took place in the Mathe-matical Research Institute, Lorenzenhof,Oberwolfach, Germany. This conferenceexhibited the remarkable growth of inter-est in statistics on the continent ofEurope. Also it emphasized a certainshift in emphasis in statistical researchin general. For these reasons, a brief ac-count of the conference may be of gen-eral interest.As is well known, up to the end of

World War II, the geographical loca-tion of research in statistics and in prob-ability was extremely uneven. Statisticaltheory (that is, theories of tests of hy-potheses, of estimation, and of decisionfunctions) was developed mostly in Eng-lish-speaking countries and was largelyignored in western Europe. Probabilitytheory centered in France and in Russia,while English-speaking countries trailedbehind. After the end of the war, thissituation changed radically. The worksof Bochner, Doob, Feller, and Loevebrought this country to the forefront ofprobabilistic research, and, at the sametime, there appeared in Europe several

young centers of research in statisticsvhich promise remarkable developments.

In addition to this geographical redistri-bution of effort, the end of the warmarked a change in the subject of sta-tistical research which may justify a dis-tinction between what may be called theclassical and the modern theories of sta-tistics. I propose to use the term classicalto describe those sections of statisticaltheory that deal with numerical randomvariables. They may be exemplified (i)by measurements, subject to randomerror, of a given physical magnitude;(ii) by responses to a treatment of or-ganisms selected at random from theirpopulation; (iii) by pairs of numbers ofions generated by a cosmic ray particlein two adjoining unit lengths of its path;.and so on. In each of these cases we dealwith a chance mechanism producingnumbers, either singly or in pairs or ipmultiple groups. More recently, modernscience and modern industry broughtunder consideration more complicatedchance mechanisms, connected with theterm stochastic processes, which, at asingle trial, produce not just a singlenumber or a finite set of numbers butmore complicated mathematical entities.such as a function. In the classificationproposed, the term modern theory of sta-tistics is applied to the statistical theoryrelating to stochastic processes that is,

American Association for the Advancement of Science1848 110th Anniversary 1958

SECTIONS: Indicate below the section(s) in which you are interested.

A ---MathematicsB PhysicsC ChemistryD- AstronomyE -Geology and Geog-

raphyF Zoological SciencesG Botanical SciencesH AnthropologyI Psychology

K Social and EconomicSciences

L History and Philoso-phy of Science

M EngineeringN Medical SciencesNd DentistryNp Pharmacy0 AgricultureP Induxstrial ScienceQ- Education

APPLICATION FOR MEMBERSHIP IN AAAS

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Mail this slip and annual dues of $8.50 (enclose check or money order) to AAAS, 1515 Mass.Ave., N.W., Washington 5, D.C. (Dues include one year of SCIENCE.)

1450

to random variables whose possible valuesare not numbers but functions.The basis for this subdivision of sta-

tistical problems into the categories "clas-sical" and "modern" is the difference inthe mathematical apparatus needed fortheir treatment. Consider a classicalproblem of statistics with some n observ-able numerical random variables X1,X.,

. . ,X.. The possible values of each Xiare numbers. Hence, if one visualizes then-dimensional Euclidean space, a singleobservation on these variables can berepresented by a single "point" with itsfirst coordinate equal to X1, its secondcoordinate equal to X2, and so on. Theprobability that the random point(X1,X9, . . . X,,) will fall within anyspecified region, say R, is then repre-sented by the measure of this region. Thetheory of measure is based on the worksof Borel and Lebesgue, developed earl)in this century and now commonly taughtin all universities with reasonably devel-oped mathematical programs. The situ-ation is different with modern statisticalproblems in which the outcome of a sin-gle "trial" is a curve, say f(x) for valuesof x between zero and unity. If one triesto extend to this case the representationof the outcome of a trial by a point, it isnecessary to deal, roughly speaking, withas many coordinates as there are num-bers between zero and unity-that is, thecontinuum. For "spaces" filled withpoints of this kind ("abstract spaces").one needs a definition of "distance," of"measure," and so forth. Theories ofthese concepts (Hilbert spaces, Banachspaces, and so on) are of more recentorigin and are included in our universityprograms only in the most advanced in-stitutions.

As far as "modern" problems are con-cerned, it was logical and unavoidablethat their probabilistic treatment shouldprecede their statistical treatment. Thepriority here belongs to the Russianschool of Kolmogorov and Khintchine.More recently, the remarkable book bvDoob clarified many concepts andcleared new paths. While it is difficult topoint out exactly the first attempts atstatistical problems concerned with sto-chastic processes, we certainly owe agreat deal to the Scandinavian schoolof Cramer, particularly to Grenander.However, modern statistical theory isstill in its infancy. One reason for thisstate of affairs is the tendency of statis-ticians to concern themselves with theso-called "practical" problems suggestedby various fields of application, and, untilrecently, both science and industry of-fered only problems with numerical ran-dom variables. However, currently oneencounters a number of problems wherethe observable random variables arecurves. One example must suffice. The"observations" by a radio telescope pro-vide a single oscillating curve summariz-

SCIENCE, VOL. 127

ing the radio emissions of all the sourceslocated within a certain solid angle. Cos-inological theories are concerned withthe spatial distribution of these sources(one particular chance mechanism) andwith the distribution of their individualintensities 'another chance mechanism).Also, the records of emission of the cos-mic radio sources are combined by thetelescope with unavoidable "noise" (athird chance mechanism). The statisti-cal problem here is to use the observablerandom curve in order to verify this orthat cosmological theory. Modern indus-try provides similar problems. Thus, thedomain of probability distributions inabstract spaces that, until recently, wasfrequently considered one of the dreanumof abstract-minded pure mathematicians,is now rapidly becoming a domain ofpractical statistical problems. In orderto stand up to these practical deinands,the efforts of theoretical statisticians mnuisthe reoriented.The conference in Loreuzenhof re-

flected both of the changes indicated:the change in the geographical distri-bution of effort in statistical researchand the change from classical to modernstatistical problems. Of the 42 partici-pants, 32 were from Germany and tenwere from other countries (three fromthe United States and one each fromAustria, Czechoslovakia, Egypt, Finland,France, Holland, and Hungary). Eachof the foreign visitors and nine Germanswere asked to present papers. The con-tents of these papers are far too techni-cal to be reported here, and the follow-ing brief enumeration is limited to casesasxhere the contributions at the confer-ence indicated the emergence of a newstatistical research center on the conti-nent of Europe. There appear to be atleast five such centers, each inspired byan outstanding personality. Roughly,from West to East, these centers areParis, Hamburg, Munich, Prague, andBudapest.

For quite some time Paris has been oneof the foremost centers of research inprobability. However, the theory of sta-tistics seemed to attract less attention.Nowse this situation has changed. and theconferences at Lorenzenhof were muchimpressed by a very interesting statisticalpaper by Robert Fortet, a noted proba-bilist. This paper dealt with the theoryof testing statistical hypotheses concernedwith stochastic processes and establishedan intriguing connection with Shannon'stheory of information.Hamburg was represented by L.

Schmetterer, leader of the group; by therecently appointed docent, Krickeberg;and by a group of promising graduatestudents. Incidentally, Schmetterer wasresponsible for the organization of thescientific program of the conference atLorenzenhof. His own paper was proba-bilistic and dealt with limit theorems ongroups. Krickeberg spoke on convergence20 JUNE 1958 1451

of stochastic processes and exhibitedsigns of the influence of Doob.The center of Munich provided four

active participants, D. Bierlein, K. Jak-obs, K. Gaede, and H. Richter. The firstthree spoke on problems of probability,while Richter dealt with Lindley's ver-sion of the statistical decision problem.The same problem was also treated byE. Brandau of Tubingen.The two statistical groups of eastern

Europe, one in Prague and the other inBudapest, were represented at the con-ference by their respective leaders, A.Spacek and A. Renyi. Their papers tes-

tified to the very intense and modernactivity of the two groups and wereloaded wtih material.

While several of the papers men-tioned, and also some of those omittedfrom the above enumeration, were essen-tially probabilistic in character, they in-cluded distinct statistical elements. Also,predominantly, the papers presenteddealt with modern problems.

Taking into account the activities ofthe new centers just described, togetherwith those of the older centers in Hol-land, Denmark, Scandinavia, and Po-land, all subject to a considerable extent

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to influences of the Russian school, oneobtains the impression of a very strongdrive now prevalent in Europe towardsthe development of an important newchapter of statistical theory.The present account would be incom-

plete without a few lines about theMathematical Research Institute atLorenzenhof. Erected in the hills ofSchwartzwald early in this century, theLorenzenhof was intended to serve asthe hunting lodge of a magnate. In duecourse it became the property of the stateand, in 1944, became the seat of theMathematical Research Institute. Origi-nally, the intention was to concentratecertain branches of war research in theinstitute. However, in practice, theLorenzenhof became a refuge for someof the German mathematicians who, forvarious reasons, had to abandon theiruniversity positions. Currently, under thewise guidance of its director, W. Sfissof Freiburg University, and of his col-league and friend, H. Kneser of Tii-bingen University, the activities of theinstitute consist of the organization ofsome 12 mathematical symposia peryear. Each symposium is given to a sepa-rate mathematical discipline and lastsabout a week. From time to time, indi-vidual mathematicians come to Lorenz-enhof for a period of quiet work.As a means for fostering research, the

usefulness of the institute and of itssymposia is supreme. Leisurely life inbeautiful surroundings, divided betweena moderate number of lectures, walks inthe countryside, and occasional periodsof good music, creates excellent oppor-tunities for informal contacts and dis-cussions which have a most beneficialinfluence on the development of mathe-maticians in Germany and, through asubstantial attendance from abroad, alsoelsewhere. One cannot help asking: Whatabout establishing a similar institutionin the United States?

JERZY NEYMANMiller Institute forBasic Research in Science,University of California, Berkeley

Hot Laboratories

Abstracts for papers to be presentedat the seventh Conference on Hot Labo-ratories and Equipment, to be held inCleveland, Ohio, April 1959, are due on15 September 1958 and should be sentto the program chairman: L. G. Stang,jr., Brookhaven National Laboratory,Upton, N.Y. Deadline for papers will beannounced later. Papers are invited onall phases of hot laboratories and equip-ment for handling radioactive material,including design, construction, operation,maintenance, decontamination, remodel-ing, shielding calculations, costs, and soforth.

SCIENCE, VOL. 127

1

First All-India Conferenceof ZoologyThe Zoological Society of India is or-

ganizing the first All-India Congress ofZoology, to be held in Calcutta from 31October to 6 November. This is the firsttime that an attempt has been made tobring together all the zoologists in India.A number of delegates from foreigncountries are also expected to attend.Dr. B. S. Chauhan of the ZoologicalSurvey of India, Calcutta, is the localsecretary. The last date for submission ofpapers to be read before the congressis 15 August.

Society Elections

*Oregon Academy of Science: pres., C.R. Monk, Willamette University; v. pres.,Lloyd W. Staples, University of Oregon;past pres., E. C. Gilbert, Oregon StateCollege; sec., and representative to theAAAS Council, F. A. Gilfillan, OregonState College, Corvallis, Ore.; treas., E.A. Yunker, Oregon State College.

* National Association for Research inScience Teaching: pres., Thomas P.Fraser, Department of Science Educa-tion, Morgan State College, Baltimore,Md.; v. pres., Vaden W. Miles, PhysicsDepartment, Wayne State University;sec.-treas., Clarence M. Pruitt, Univer-sity of Tampa, Tampa, Fla. The repre-sentative to the AAAS Council is GeorgeG. Mallinson.

* American Society of Ichthyologists andHerpetologists: pres., Edward H. Taylor;treas., James E. Bohlke, Academy ofNatural Sciences, Philadelphia, Pa.; sec.,Roger Conant, Philadelphia Zoo, 34thSt. and Girard Ave., Philadelphia 4, Pa.The vice presidents are: Boyd W.Walker, Department of Zoology, Univer-sity of California; John C. Marr, La-Jolla, Calif.; James A. Kezer, Depart-ment of Biology, University of Oregon.

Forthcoming Events

July20-23. National Shellfisheries Assoc.,

49th annual, Baltimore, Md. (P. A. But-ler, U.S. Shellfisheries Laboratory, GulfBreeze, Fla.)

20-27. Americanists, 33rd intern. cong.,San Jose, Costa Rica. (33rd Intern.Cong. of Americanists, National Museum,P.O. Box 749, San Jose de Costa Rica,Central America.)

21-24. High Polymer Conf., intern.,Nottingham, England. (Conference Sec-retariat, Dept. of Scientific and IndustrialResearch, Charles House, 5-11, RegentSt., London, S.W. 1.)

22-26. Brazilian Soc. for the Progressof Science, 10th annual, Sio Paulo, Brazil.Sociedade Brasileira para o Progresso da20 JUNE 1958

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Society of Systematic Zoology. (R. E.Blackwelder, Box 500, Victor, N.Y.)Tomato Genetics Cooperative. (E. C.

Stevenson, Horticulture Dept., PurdueUniv., West Lafayette, Ind.)

24-29. Atmospheric Diffusion and AirPollution, intern. symp., Oxford, England.(F. N. Frenkiel, Applied Physics Lab.,Johns Hopkins Univ., Silver Spring, Md.)

24-29. Mental Health, world federation,1 1 th annual, Vienna, Austria. (Miss E.M. Thornton, World Federation for Men-tal Health, 19 Manchester St., London,W. 1, England.)

24-30. Prehistoric and ProtohistoricScience, 5th intern. cong., Hamburg, Ger-

many. (Biiro des Internationalen Kon-gresses fur Vor- und Friigeschichte, c/oFremdenverkehrs- und Kongresszentrale,Hamburg 1, Bieberhaus, Hachmannplatz.)

25-28. Institute of Mathematical Sta-tistics, annual, Cambridge, Mass. (G. E.Nicholson, Jr., Dept. of Statistics, Univ.of North Carolina, Chapel Hill.)

25-28. Mathematical Assoc. of America,39th summer, Cambridge, Mass. (H. M.Gehman, Univ. of Buffalo, Buffalo 14,N.Y.)

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GENERALS ELECTRIC1456

LettersWithdrawal versus Withholdingof Positive Reinforcement

C. B. Ferster (1) in his experimentsused withholding of food reinforcement(called by him withdrawal of positivereinforcement) in differentiation of con-ditioned motor reflexes. It seems, how-ever, that under the circumstances of hisexperiments, the procedure cannot beconsidered as "the withdrawal of posi-tive reinforcement" nor as "the with-drawal of the situation in which the re-inforcement occurs." The situation inwhich the reinforcement occurred wasonly partially changed by switching offof the overhead lamp, or by appearanceof the red light, and in spite of the factthat the animal performed the move-ment (pressing of the key), the rein-forcement was withheld. The differen-tiation which was attempted in theseexperiments developed slowly and wasonly a partial one, because the reinforce-ment was withheld regularly only whenthe movement occurred during periodswhen the red light appeared, whereas inthe absence of the red light the rein-forcement was applied irregularly.

Ferster emphasizes in his report theanalogy between the punishment and thewithholding of positive reinforcement,both of which had as a result the elimi-nation of the conditioned movement.But I think that there is a very impor-tant difference between the two events:the punishment, whether used in classicconditioning (type I) or in escape oravoidance conditioning (type II) (2),can give rise to new conditioned move-ments, whereas the differential inhibi-tion can only eliminate some preexistingconditioned movements. The suggestionthat punishment and differentiation havecommon "aversive" features is, as of thepresent time, based only on introspectiveimpressions.

In my own experiments (3), whenreal withdrawal of positive reinforce-ment was used, a new kind of behaviorwas obtained. These experiments con-sisted in the withdrawal of food duringthe act of eating. The withdrawal wassignaled by an acoustic stimulus applied5 to 10 seconds beforehand. After sev-eral such trials the animal stopped eatingwhen the stimulus sounded and turnedaway from the food tray. This condi-tioned "cessation reflex" was later differ-entiated: the food was withdrawn afterone of the stimuli, hut after another itwas not. During the action of the firststimulus the dog turned away from thefood, but during the action of the other(that which was not reinforced by with-drawal of food), he ate without inter-ruptions.

Thus, both the inhibition produced bySCIENCE, VOL. 127

withdrawal of food and punishment bypain reinforcement may give rise to newconditioned movements.

A. W. ZBROZYNADepartment of Neurophysiology,Nencki Institute of ExperimentalBiology, Wl'arsaw, Poland

References

1. C. B. Ferster, Science 126, 509 (1957).2. S. Miller and J. Konorski, Compt. rend. soc.

biol. 99, 1155 (1928); J. Konorski, ConditionedReflexes and Neuron Organization (CambridgeUniv. Press, Cambridge, 1948).

3. A. W. Zbrozyna, Acta Physiol. Polon. 3, 70(1952); Bull. acad. polon. Sci. Classe VI, 5,261 (1957); Acta Biol. Exptl. Warszawa, inpress.

A. Zbrozyna is correct in stating thawin establishing the aversive event in myexperiment I did not withdraw all ofthe stimuli correlated with reinforce-ment. The stimulus I withdrew is theone differentially correlated with rein-forcement. The conditioned response wasnever reinforced in the absence of theoverhead light, while, alternately, it wasintermittently reinforced in its presence.That the rate of pressing the key fell tozero in the absence of the overhead lightis evidence of its effectiveness. The aver-sive nature of the absence of the over-head light is demonstrated by the sup-pression of key pressing during a secondstimulus preceding the termination ofthe experiment (warning stimulus).

This experimental procedure has beenstudied extensively with electric shockas the aversive stimulus (see 1). Whetherthe degree of awversiveness of the stimix-hIis correlated with the nonreinforcemen.of the conditioned response depends onhow many of the stimuli present duringreinforcement are withdrawn is an ex-perimental question worth raising. Forexample, would the discontinuation ofthe reinforcement of key pressing bemore aversive if we physically removedthe animal from the experiment for 60minutes rather than "prevented" himfrom emitting the conditioned responseby presenting a stimulus in whose pres-ence the conditioned response has con-sistently gone unreinforced in the past?The paradigm used in my experiment

investigates only one aspect of an aver-sive stimulus: the suppression of someon-going. positively reinforced behaviorby a stimulus preceding the aversiveevent. Other properties of aversive stim-uli (such as electric shock) not studiedin this experiment include (i) the prop-erty of maintaining another responsewhich terminates, postpones, or avoidsthe aversive event; (ii) the property ofdifferentially suppressing conditioned orotherwise maintained behavior by pun-ishment-that is,, by application of theaversive event to the response that is tobe suppressed. Experiments demonstrat-ing both the first (2, 3) and secondproperty (2) of the discontinuation of20 JUNE 1958

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positive reinforcement have already beencarried out, although they have not yetbeen published.

C. B. FFRSTFR,Institute of Psychiatric Research,Indiana University, IndianapolUs

References

1._2.

J. V. Brady, Science 123, 1033 (1956).C. B. Ferster, Psychol. Monographs, in press.R. J. Herrnstein and W. H. Morse, Am. Psy-cIhologist Abstr. (1956).

Prepublication Problems

The editorial in Science [127, 623(1958)] on "Pitfalls of prepublication"called attention to a new type of scien-tific publication problem.

Problems of printing the works ofproductive, perhaps overproductive,scholars are old ones. By the 17th century,for example, the practice of rushing intoprint was deplored by William Harvey,who wrote of "the crowd of foolishscribblers whose observations were as in-consequential as their theories werewordy" (1). Lilienthal, in his De Machi-avellismo Literario, likened the offspringof such scholarly productivity to blindwhelps brought forth without pain (2).Johann Mencken, writing in 1715 in DeCharlataneria Eruditorum (3), could notoverlook mentioning "those writers whoconsider themselves suitably blessed ifno year, or better, no month passes with-out receiving something new from theirexceedingly fruitful minds."

Until I read the Science editorial, how-ever, I had been aware of only onecomplaint regarding prepublication pro-ductivity. That complaint concernedParacelsus, who dictated the majority ofhis books. One of his students complainedthat they were dictated at such a speed"you'd think that the devil was speakingin him" (4). This prepublication com-plaint is interesting historically but barelyapplicable, because Paracelsus' bookswere handwritten manuscripts.

Today, however, all sorts of duplicat-ing processes exist, making possible anextensive, but strictly informal, kind ofpublication-that is, prepublication. TheScience editorial mentioned one reasonfor prepublication: accelerating the re-search process. Sending mimeographedcopies of articles in press to colleaguesmakes them immediately cognizant of in-formation that may not appear formonths or, in the case of some journalsin my own field, for years. In the fieldof psychology, three other reAsons forduplicated copies have been advanced:(i) There is a growing tendencv for con-vention "handouts" to take the form offull drafts of the paper to be read (5).(ii) Brief reports, limited to one printedpage, are solicited by one journal forearly publication. An author, however, is

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SCIENCE, VOL. 127

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required to prepare at least 100) mimieo-oraphed copies of a full report of the re-search study to send without charge toall who request it (6). (iii) Authors ofmanuscripts not yet submitted for publi-cation are routinely advised to give thema "trial run" on professional colleagues(7). In many cases the feeling seems tobe "the more the merrier," and mimeo-graphed copies are scattered broadside.A few years' collection of such items

may result in confusion about citationsand reduce the helpfulness of the refer-ence section of articles. Gradually, afixed procedure is being introduced inpsychological writing (7). For example,only articles accepted for publicationmay be designated "in press.' In suchcases the name of the accepting journalis part of the citation form. If a paperhas been presented at a meeting, the pre-ferred forms of citation are (in order ofrank) to the published version of thepaper, to the published abstract, or (if itis essential to cite the paper and no ver-sion exists in the professional literature),to the title and author, followed by ablanket citation, such as "paper read atVa. Acad. Sci., Old Point Comfort, May,1957.' It should be noticed that thisleast preferred method eliminates cita-tion of a specific page reference for anypuotation and thus avoids difficulties oc-,caioned by editorial changes in a versionpublished later. To differentiate betweenconvention "give-aw~ays," which oftenbear only a title and the author's namefor identification, and the full reportsmentioned in (ii), I suggested that suchmaterial carry a reference to the brief.published report. My suggestion wasadopted by the editor, L. F. Shaffer (per-sonal communication). It is in the hopethat these methods will be of use to re-search workers in other fields that theyare presented here.

Early alchemists, like Paracelsus, re-sembled donkeys lured along by carrotsdnantling before their noses. Todays sci-entists are like jet planes-propelled bytheir own exhaust. For, a~l)larcntly, it isonly in our communication-conscious erathat problems of prepublication arise.Concrete remedies are necessary, lest the(xhatist eradicate bibliographic accuracy.

DFEIT LEBORich Ationd Professioiital Inilstitute,Richitiond, 'irginia

References

1. H. Graham., Eternal Eve (Doubleday, NewYork. 1951). p. 249.

2. D. Lebo, Ant. Psvrhologist 12, 158 (1956).3. T. B. Mencken, The Charlatanry of the Learned

(Knonf, New York. rev. ed of De Charlatan-eria Eruditorumn, 1937), p. 70.

4. K. Walker. The Story of Medicine (OxfoidUniv. Press. New York, 1955), p 121.

5. H. Schlosberg. Amt. Psychologist 11. 345 (1956).1. 1. Consulting Psy hol. 22. ii ( 1958).7. Publ. Manual Ain P.schol. Assoc.. Washinem-

ton. D.C., res ed. 1957). p 17; D. Lebo.Gu dehook fJor Thesis (omIpo). tion (RichmondProfessional Institute. Richmonld. Va., 1957).

20 JUNE 1958

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front manufacturers and from other sources con-sidered to be reliable. Science does not assumeresponsibility for the accuracy of the informa-tion. A coupon for use in making inquiries con-cerning the items listed appears on page I462.

* TEMPERATURE MONITORS for any tem-perature from - 4000 to + 3000'F arecomplete controls ready to connect tothermocouples and to source of power.Each monitor contains a meter-type re-lay together with transformer and recti-fier or other components for the typeof control required. Control action maybe on-off or limit with external reset.Accuracy on the order of ± 2 percentapplies to most temperatures. (AssemblyProducts Inc., Dept. 81)

* PORTABLE POTENTIOMETER PYROMETERuses interchangeable scales to adapt toa variety of thermocouples. Scales areavailable for Pt, Rh-Pt; #242-#33 al-loy; Ni-Ni 18 percent Mo; and LC typeY. The instrument also measures d-c po-tentials from 0 to 155 mv. (TechniqueAssociates, Inc., Dept. 82)

* PHASE-ANGLE METER provides directreading without ambiguity over the fre-quency range 20 to 20,000 cy/sec. Angleis indicated from 0 to 360 deg with ac-curacy ± 1 deg. Complex or sinusoidalwaveforms are accepted as input; theoutput is suitable for operation of re-corders. (Control Electronics Co., Inc.,Dept. 83)

* DUAL-BEAM OSCILLOSCOPE has verticalamplifiers with calibrated sensitivities in16 steps from 200 Iv to 20 v/cm. Fre-quency response is from direct currentto 100 kcy/sec at maximum sensitivity.Input impedance is 1 megohm, 47 pffrom 1 mv to 20 v/cm. Sweep rates areselectable from 1 msec to 5 sec/cm. Ahorizontal-input amplifier provides forcurve tracing with both beams simulta-neously at sensitivities to 0.1 v/cm.(Tektronix, Inc., Dept. 85)

* FREQUENCY STANDARD for 400-cy/secoperation is said to be position insensi-tive. Output is frequency stable within+ 0.001 percent, under environmentalconditions of vibration, from 50 to 2000cy/sec, up to 18 g; shock up to 50 g;steady-state accelerations of 20 g; andtemperature between - 200 and + 70'C.The unit is hermetically sealed. (GyrexCorporation, Dept. 86)

* RADIOACTIVITY STORAGE CONTAINER formedical applicators consists of a leadshield 2 in. thick mounted in a cubicalwood enclosure. The container will safelyshield up to 125 mc of cobalt-60 or 165mg of radium. (NRD Instrument Co.,Dept. 111 )

1460

* ULTRASONIC GAGE is self-contained forthickness gaging, recording, and detec-tion of laminar flaws and includes con-nections for automatic sorting and re-jection. Thickness between 0.005 and 2.5in. can be measured from one side of thematerial. Accuracies as high as ± 0.02percent are said to have been achievedin applications which involved observa-tions of differential between a sampleand a reference of the same nominalthickness. The output record is producedby a strip-chart recorder. Readings aremade directly, in terms of thickness.(Branson Instruments Inc., Dept. 88)

M ANALOG-TO-DIGITAL CONVERTER operatesby comparing input voltage with an in-ternal reference voltage derived by sum-ming weighted current from a precisionpower supply. The instrument is a solid-state device operating at the rate of 100,-000 bits per second to produce 6000 con-versions per second. Accuracy is ± 0.05percent of full scale. A conversion canbe initiated by a push button or by anexternally applied 2-v transient. Thereading is displayed visibly by neon in-dicators in binary-coded decimal formand is available at output terminals.Both serial and simultaneous outputs areavailable. (Fischer and Porter Co., Dept.90)

* POWER SUPPLY is designed to furnishlow-voltage a-c and d-c power for stu-dent laboratory use. The unit, whichplugs into a standard 115-v a-c outlet,may be used by as many as eight stu-dents at a time. Outputs include 6 and12 v d-c at 10 amp and 6, 12, and 24v a-c at 10 amp. Also provided are fourneon continuity lamps for circuit-tracing.(Universal Scientific Co., Inc., Dept. 89)

* SIX-CHANNEL RECORDER provides recti-linear inked or electric-stylus records. In-put range for 20-mm deflection is adjust-able from 1 to 200 v in seven steps. Driftis ± 0.5 mm in 8 hr. Six paper speeds,from 0.5 to 25 or from 1.2 to 50 mm/sec,are regulated within ± 1 percent. Re-sponse is flat to 40 cy/sec. Channel-gaincalibration is provided by an internalstandard cell. A regulated stylus powersupply is available as optional equip-ment. (Mid-Century Instrument Corp.,Dept. 109)

* GLASS-SCREENS perforated with 562,-000 precisely etched holes per squareinch are being produced for electronstorage-tube applications. Transmissionof the screens may be from 40 to 70 per-cent. The screens are manufactured by aphoto-etching process. The largest screendiameter is 1.5 in., and the thickness is0.002 to 0.005 in. (Corning Glass Works,Dept. 112)

JOSHUA STERNNational Bureau of Standards

SCIENCE, VOL. 127