23 August 1957, Volume 126, Number 3269

AMERICAN ASSOCIATIONFOR THE

ADVANCEMENT OF SCIENCE CostsBoard of Directors

LAURENCE H. SNYDER, President DunnWALLACE R. BRODE, President Elect sh rpyPAUL B. SERs, Retiring President sharply.PAUL M. GRoSS and prigGEORGE R. HARRISON from 50PAUL E. KLOPSTEG AlthoiCHAUNCEY D. LUEA that sch(MARGARET MM4D others wTHomAS PARK quenceiWILLAM W. RUBEY scholars]AAN T. WATERMAN educaticPAUL A. SCHERER, Treasurer promiseDARL WOLFLE, Executive Officer lack ofi

DAm WOLFLE, Executive Officer creasesHGRAHAM DUSHANE, Editor How 1

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SCIENCE

of Higher Educationg the last decade the cost of a college education has increasedA recent survey by the New York Times of 35 representative publicvate colleges and universities showed that tuition increases rangedto more than 100 percent in the period from 1946-47 to 1956-57.ugh spokesmen for some of the institutions in the survey thoughtolarship aid would keep pace with the rise in costs, spokesmen forrere not so hopeful. An important and socially undesirable conse-of the tuition increases, insofar as they are not met by additional;hip aid, will be to bar some well-qualified students from higherin on purely economic grounds. This is, of course, not new. Someng students have always been prevented from going to college bymoney. But, if it is not new, it is intensified, and further rapid in-may deter a proportionally larger number of students.great is the loss of potential college students? Charles C. Cole, Jr.,tdean of Columbia College, attempted to answer this question lastin a study carried out for the College Entrance Examination Boardgrant from the National Science Foundation. Cole estimated that)0,000 high-school students who were in the upper 30 percent ofnior classes last autumn failed to go on to college; some 700,000,whom were not as well qualified, did go. The loss is substantial,

an be attributed only in part to lack of funds. Of the 200,000 Colethat about 50,000 had considerable potential scientific ability, andluded that between 8000 and 15,000 male high-school students ofcup "could be retrieved if they could be found and provided witht financial aid to enable them to go to college."the states should make some contribution to education has longcognized, as is shown by tax exemptions granted to private collegesiversities and by state support of public institutions. The Federalment has a long record of support of education from the Morrill Actwhich made possible the land-grant colleges, to recent grants for

land training.partial support of the institutions of higher education is a well-

hed function of both state and federal government. The direct sup-students is more recent and more fragmentary. A few states, Cali-and New York among them, have extensive scholarship programs.cderal Government has, aside from financial aid during the depres-d scholarships to veterans of World War II and the Korean War,of. The numerous scholarship bills introduced at each recent sessionrress have died in committee.a hopeful sign that private and industrial donations, both for oper-Kpenses and scholarships, are increasing and that a National Meritship Program has been launched with support from the Fund forvancement of Education and from industrial donors. The proposalIE. Klopsteg of a tax adjustment that would greatly encourage pri-cd industrial gifts to education is attracting widespread interest [Sci-4, 965 (1956)]. In addition, for those who have some financial re-,the pay-as-you-go plan for tuition and board and eoom is'helpful.reasing number of colleges and universities are entering contractsNew York corporation, Tuition Plan, Inc. Tuition Plan pays theional fees in a lump sum in September and January and bills parentsy. The only cost is a 4-percent carrying charge to the parents. Thisinstallment payments for education has caught on rapidly: in 1955,ts totaled $8.7 million; in 1956, $12 million; in 1957, $30 million; inn estimated $100 million.too early to tell what final balance between public and private sup-ill be worked out, but the vigorous discussion and numerous plansounds for the hope that some way will be found to see to it that nod person fails to attend college for financial reasons.-G. DuS.

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THE RICKETTSIALDISEASES OF MAN

0 This symposium volume is a comprehensive sur-vey of the general field of Rickettsial diseases inman. Among the contributors appear the names ofmany of the foremost American authorities in thisimportant and relatively new field of medicine.

* The first group of papers includes discussions ofthe taxonomy, biology, isolation, and identificationof vectors, and reservoirs of infection of the Rick-ettsial diseases of man. The second group of papersis devoted to discussions of serological reactions, theWeil-Felix reaction, the complement-fixation andagglutination reactions, and the preparation andstandardization of Rickettsial vaccines. The finalgroup of papers treats of insecticides, methods oftheir application, and mite control.

To: AAAS Publications1515 Mass. Ave., N.W., Washington 5, D. C.

Please accept my order for one copy of TheRickettsial Diseases of Man (7%,4 x lU'/2, cloth-bound). My check in correct payment is enclosed($5.25 to A.A.A.S. members, $6.25 to those whoare not members; including postage.)

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4. Role of Agriculture in Future Soci-ety, 75th anniversary symp., Geneva, N.Y.(New York State Agricultural ExperimentStation, Cornell Univ., Geneva.)

4-6. Indiana Geologic Field Conf., 9th,Mitchell, Ind. (H. H. Gray, Indiana FieldConf., Dept. of Conservation, GeologicalSurvey, Bloomington, Ind.)

6-10. Electrochemical Soc., fall, Buf-falo, N.Y. (H. B. Linford, 1860 Broad-way. New York 23.)

7-9. National Electronics Conf., Chi-cago, Ill. (J. S. Powers, NEC, 84 E. Ran-dolph St., Chicago 1.)

7-11. American Inst. of Electrical En-gineers, fall general, Chicago, Ill. (N. S.Hibshman, AIEE, 33 W. 39 St., NewYork 18.)

7-11. Research Contributions to Clini-cal Practice, New York Acad. of MedicinePostgraduate Week, New York. (Secre-tary, Postgraduate Week, New York Acad.of Medicine, 2 E. 103 St., New York 29.)

8-10. International Assoc. of Milk andFood Sanitarians, annual, Louisville, Ky.

(H. H. Wilkowske, Dairy Science Dept.,Univ. of Florida, Gainesville.)

8-10. Upper Air Conf., American Me-teorological Soc., Omaha, Nebr. (K. C.Spengler, AMS, 3 Joy St., Boston 8.Mass.)

9-11. High Vacuum Technology, 4thannual symp., Boston, Mass. (Committeeon Vacuum Techniques, P.O. Box 1282,Boston 9.)

9-11. Society for Experimental StressAnalysis, fall, San Diego, Calif. (W. M.Murray, SESA, P.O. Box 168, Cambridge39, Mass.)

9-12. Tau Beta Pi Assoc., annual, Madi-son and Milwaukee, Wis. (R. H. Nagel,Univ. of Tennessee, Knoxville.)

10-1 1. Noise Abatement Symp., 8th an-nual, Chicago, Ill. (J. J. Kowal, ArmourResearch Foundation, 10 W. 35 St., Chi-cago 16.)

10-13. Angiology, 3rd internatl. cong..Atlantic City, N.J. (H. Haimovici, 105 E.D0O St., New York 28.)

11-13. Iroquois Research, 11th conf.,

in balances...

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368

Red House, N.Y. (W. N. Fenton, NewYork State Museum, Albany 1.)

12. Fat and Diabetes Symposium, NewYork, N.Y. (T. Kingsley, New York Dia-betes Assoc., 104 E. 40 St., New York 16.)

13-18. American Acad. of Ophthalmol-ogy and Otolaryngology, annual, Chicago,Ill. (W. L. Benedict, 100 First AvenueBldg., Rochester, Minn.)

14-16. Association of Official Agricul-tural Chemists, 71st annual, Washington,D.C. (W. Horwitz, Box 540, BenjaminFranklin Station, Washington 4.)

14-18. American College of Surgeons,43rd annual clinical cong., Atlantic City,N.J. (ACS, 40 E. Erie St., Chicago 11,Ill.)

14-18. American Soc. of Civil Engi-neers, New York, N.Y. (W. H. Wisely,ASCE, 33 W. 39 St., New York 18.)

14-18. International Industrial Devel-opment Conf., San Francisco, Calif. (E. S.Prentice, Stanford Research Inst., MenloPark, Calif.)

16-23. Enzyme Chemistry, internatl.symp., Tokyo and Kyoto, Japan. (Inter-national Symp. on Enzyme Chemistry,Science Council of Japan, Ueno Park.Tokyo.)

17-18. American Ceramic Soc., 10thPacific Coast mtg., San Francisco, Calif.(C. E. Pearce, ACS, 4055 N. High St.,Columbus 14, Ohio.)

17-18. Industrial Hydraulics, natl.conf., Chicago, Ill. (Conference Secre-tary, Armour Research Foundation, 10 W.35 St., Chicago 16.)

17-19. Indiana Acad. of Science,Greencastle. (H. Crull, Dept. of Mathe-matics, Butler Univ., Indianapolis 7, Ind.)

17-19. Optical Soc. of America, Co-lumbus, Ohio. (S. S. Ballard, VisibilityLab., Scripps Institution of Oceanog-raphy, San Diego 52, Calif.)

18-19. National Soc. of ProfessionalEngineers, Bismark, N.D. (P. H. Robbins,2029 K St., NW, Washington 6.)

19-26. Social Work, 3rd Pan Americancong., San Juan, Puerto Rico. (A. PorrataDorla, Apartado 3271, San Juan.)

20-22. American College of Apothe-caries, St. Louis, Mo. (R. E. Abrams,Hamilton Court, Chestnut and 39 St.,Philadelphia, Pa.)

21. Air Pollution Symp., 2nd annual,Philadelphia, Pa. (A. D. Hollingsworth,Franklin Inst., Benjamin Franklin Park-way at 20th, Philadelphia 3.)

21-25. Medical Aspects of Workmen'sCompensation, New York. (Office of As-sociate Dean, New York Univ. Post-Grad-uate Medical School, 550 First Ave., NewYork 16.)

21-26. Ultra High Frequency Circuitsand Antennas. internatl. conf., Paris,France. (Congres Circuits et AntennesHyperfrequences, Societe des Radioelec-triciens, 10, Avenue Pierre-Larousse,Malakoff (Seine), France.)

22. American Soc. of Safety Engineers,annual, Chicago, Ill. (J. B. Johnson,ASSE, 425 N. Michigan Ave., Chicago11.)22-25. American Dietetic Assoc., an-

nual, Miami. Fla. (Miss R. M. Yakel,ADA, 620 N. Michigan Ave., Chicago 11,Ill.)

(See is su of 16 1Augu.% for iompr/prchnsie. list)

SCIENCT. VOL. 126

LETTERSThe editors take no responsibility for

the content of the letters published in thissection. Anonymous letters will not be con-

sidered. Letters intended for publicationshould be typewritten double-spaced andsubmitted in duplicate. A letter writershould indicate clearly whether or not hisletter is submitted for publication. For ad-ditional information, see Science 124, 249(1956) and 125, 16 (4 Jan. 1957).

Autoradiography: Terminologyand Definition

D. L. Joftes and S. Warren [Science124, 1155 (1956)] recommend the term

radioautography in preference to auto-

radiography [W. N. Tauxe, A. H. Moser,and G. A. Boyd, Science 120, 149 (1954);G. A. Boyd, Autoradiograph) in Biologyand Medicine (Academic Press, NewYork, 1955)]. Joftes defines this tech-nique, in part, as a method by which an

image is obtained in which the image'corresponds to the distribution of a

radioisotope within an object"; theimage is "the result of radiation fromthe contained isotope and does not

necessarily correspond to the interiorstructure."

I am convinced that the prefix auto

should be used in the prime position(thus, autoradiography) for etymologi-cal reasons and beg the indulgence ofJo.tes and Warren in such use in thiscommunication. The primary purpose

of this letter is not to comment on

semantic and etymological merits of thetwo terms but rather to point up theneed either for new terms for certaintechniques that are identical to, or very

closely akin to, autoradiography, or forrevision of the foregoing definition ofthe technique. The definition attributedto Joftes and Warren limits the auto-

radiogram to an image correspondingto radioisotope distribution "within"an object. Such a concept does not

recognize the broad implications of thetechnique in physics, metallurgy, chem-istry, and geology, beyond the classicalhistological applications. Where such a

definition is accepted, then certain in-stances of work could not be definedas autoradiography although the methodseems best identified by this term. Twoexamples follow:

1) This is a technique in which a sur-

face is selectively covered with a radio-active isotope in very thin film form[L. E. Preuss, Nucleonics 12, No. 8,(1954)], and the intimate detail of thatsurface is reproduced through latentphotographic image production, by theconventional gross apposition technique,in which an appropriate photographicemnulsion is used. This may be gener-ally categorized within the techniqueunder discussion except for the fact thatthe radioisotope is not imbedded withinthe object.

23 AUGUST 1957

2) This is a systemn by which a radio-isotope is laid down on a uniform sub-strate to form a pattern not related tothe substrate (L. E. Preuss, in a paperpresented before the National VacuumSymposium, Chicago, Ill., 11 Oct.1956). This pattern is duplicated againby the gross apposition technique on anautoradiographic emulsion. However,this does not fall into the category ofJoftes' "radioautography," since the iso-tope is on a surface and not in an ob-ject. To go farther afield for anotherexample, Erik Odeblad [Acta Radiol.43, 145 (1955)] discusses a method ofradioisotope self-photography and termsit "pin-hole autoradiography." Here,the source is removed from the emulsionduring the latent image production.

Perusal of the foregoing techniques.the classical histological applications,and the host of other modifications ofautoradiography, too numerous to men-tion, discloses two obvious features thatare common to them all, throughout.The first essential is a radioisotope ina particular pattern or array. The sec-ond is the photographic impression ofthat pattern by radiation-stimulatedlatent image production.The first two examples outlined seenm

to fill the general conception of auto-radiography, yet the radioisotope is not-within the object.' Shall these becalled "autoradiography," but withmodifying terms to give specific mean-

ing, such as "surface detail autoradiog-raphy by gross apposition," for the firstexample? Such a system is pedantic.The logical alternative is to alter Joftes'definition to one which is more inclu-sive. It becomes apparent, as time goeson, that multitudinous variations willbe played on the theme of the originaltechnique by scientists in every realmof investigation. Thus, a general defini-tion which is not restricted by the limi-tation within one discipline seems logi-cal.

I submit that autoradiography consistsof two essentials: (i) The presence ofa radioisotope in some significant array

(not necessarily, within a matrix); and,(ii) the reproduction of this arraythrough photographic latent image pro-duction by the attendant radiation.

Therefore, I propose the following as

a more general alternative definition:"Autoradiography is that method inwhich a photographic response preciselyreproduces the significant array of a

radioisotope. The isotope may or maynot exist within or on some supportingstructure or substrate, the latent imageproduction being attributable to the iso-topic radiation."

Such a general definition will satisfythe conditions for use of the term bythe chemist, geologist, physicist, histolo-gist, and other workers. It may be em-

phasized that autoradiography is not

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only applicable to location studies ofisotopes in tissues but in the investiga-tion of surface layers as well as self-supporting structures of the isotopesthemselves. Thus, the limitation, bydefinition, that the isotope must be con-tained within the matrix of some struc-ture is not logical. It is my convictionthat this method has now become socommon and unrestricted in applicationto all phases of science that such adefinition is contrary to the generallyaccepted meaning of the term.

LUTHER E. PREUSSEdsel B. Ford Institute for MedicalResearch, Detroit, Michigan

Preuss criticism is based on the er-roneous assumption that we were at-tempting to promulgate the definitivedefinition of radioautography. Actually,ours was simply a working definition,used to describe the basic conditions ofradioautography. The fact remains thatin all radioautographic techniques, in-cluding those of Preuss, there is no ex-ternal source of radiation which pene-trates the object and therefore there isno radiography auto or otherwise.Autoradiography is a self-contradictoryterm.

As for defining terms, any definition,including that of Preuss, is open to criti-cism for the reason advanced by Preusshimself namely, lack of sufficient gen-erality to encompass all the permuta-tions to which the technique is suscep-tible. For instance, Boyd suggests thatthe use of photographic emulsions(which Preuss makes a condition of his"general" definition) do not have to bethe sole method of registering the image.Other materials that are sensitive toradiation and can be caused to yield avisual image may be used. This kindof hairsplitting is futile and will serveus ill in the long run.

Preuss' definition would be accept-able if it were amended as follows:"Radioautography is a method by whichan image is obtained which reproducesthe array of a radioisotope or isotopesduring exposure of a radiation-sensitivematerial. The isotope(s) may existwithin, on, or near the structure or sub-strate under investigation, the image ob-tained being attributable to the radia-tion emanating from the isotope."Doubtless even this definition is notbroad enough.

I hope that my acceptance of all themain elements of his definition will in-duce a similar attitude of conciliationin Pruess and that he will accept thebasic point of the original comment anduse the term radioautography for theingenious methods which he has de-veloped.

DAVID L. JOFTESCancer Research Institute,Boston, Massachusetts

SCIENCE, VOL. 126

WJ1 1 14 ._MYA..

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EQUIPMENT NEWS

The 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).

* TRANSISTOR CURVE TRACER displayscharacteristic curves of p-n-p and n-p-ntransistors on the face of a cathode-raytube. Four to 12 curves per family are

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* COORDINATE CATHETOMETERS make botha horizontal and a vertical measurementin a vertical plane in one setting. Thecathetometer consists of a microscope or

telemicroscope mounted so that it can bemoved on a vertical bar. This assemblyin turn may be moved laterally on hori-zontal ways. Micrometer screws providefine adjustments. Coordinate ranges from2 by 2 in. to 42 by 42 in. are available.(Gaertner Scientific Corp., Dept. S516)

* METAL DETECTOR has an inspectionaperture measuring 64 by 1/8 in. throughwhich the material to be checked passes.Magnetic or nonmagnetic metals are de-tected. Sensitivity is adjustable for de-tection of particles as small as 0.039 in.in diameter. Distortion by metal of thehigh-frequency electromagnetic field thatis set up in the aperture creates an elec-tric signal, which is amplified to triggeran alarm. Strip material can be inspectedat speeds of from 10 to 1000 ft/min.(Radio Corporation of America, Dept.S518)

I CODING DISKS, for shaft-rotation ana-

log-to-digital conversion, are now offeredwith nonlinear and decimal codes. Thedisks can be mounted in the manufac-turer's standard 6- and 9-in. encoderhousings. Decimal code disks up to 100,-000 are available. Nonlinear disks can

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checked by automatic means to 1 sec ofarc. (Baldwin Piano Co., Dept. S564)23 AUGUST 1957

* PULSE GENERATOR operates in therange from 1.6 to 10.4 Mcy/sec. Pulsesare half sine wave and are adjustable inamplitude from 1 to 30 v. Five pulsewidths are selectable in the range from30 to 70 mgsec. (Burroughs Corp., Dept.S561)

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