in specifications when no filtering isrequired, or below 10,000 ohms whenfull filtering is utilized.-R.L.B. (E. H.Sargent and Co., Dept. S217, 4647 W.Foster Ave., Chicago, Ill. 60630)

Automated hemagglutination systemis based on continuous measurementof degree of agglutination resultingfrom an antibody-antigen reaction. Thesystem provides results expressed inpercent agglutination or percent hemol-ysis, obtained from data automaticallyrecorded on a strip chart. It elimi-nates the variables inherent in manualmethods by a design that decants theagglutinated cells as they are formed.The remaining unreacted cells are thenhemolyzed. Color resulting from homol-ysis is directly proportional to theamount of cells removed and is auto-matically detected and measured. Ablank consisting of red cells and salinebut without antibody is handled in ex-actly the same way as the test sample.Colors developed by hemolysis of thecells in the blank and in the sampleare measured and recorded simultane-ously. The curve of the blank repre-sents 0 percent agglutination. Percentagglutination in the reactive circuit is

then calculated from the difference be-tween the two curves. Completely au-tomatic in operation, cells, antiserum,and reagents are correctly propor-tioned, mixed, and pumped throughthe system. All factors in the process-mixing time, proportioning, temper-ature, reaction time-are held constant.For the producer of serum and viruses,the system provides a standard proce-dure, a written record, and reproduci-ble results. For clinical and blood-bankoperations, the technique virtuallyeliminates blood typing errors. Thechart is a permanent record clearlyidentifying the sample and the corre-sponding result. Test rate of 40 com-plete typings per hour is achieved.By adding circuits, information onother reactive materials can be ob-tained simultaneously. A range of cellconcentrations from 2 to 50 percentcan be handled by changing theamount of water used for hemolysis.Cell concentrations of 1 percent andbelow are hemolyzed with an alcoholsolution of benzidine; with this re-agent, 0.001 percent cells can be de-tected. Also available are serologicalsensitizing agents-such as gum acacia,PVP, papain, ficin, dextran, and so

forth-which augment the reactionwithout developing false results.-D.J.P. (Technicon Instruments Corp.,Dept. S226, Research Park, Chauncey,N.Y.)

Vacuum evaporator attains pressuresof 5 X 10` torr in 15 minutes and theultimate is below 2 X 10` torr. Newlydeveloped traps and valves have veryhigh conductance for handling gasloads during evaporation. The large,reservoir-type trap is liquid-nitrogencooled, and has complete optical den-sity and a fully effective anti-migrationshield. The cantilevered work chamberis polished to a No. 7 finish. Top andbottom cover plates are removable andinterchangeable for maximum versatil-ity. A large, hinged sight door, with150 in.2 (968 cm2) of viewing area,provides virtually unlimited visibilityand access to the work chamber. Afull range of accessories includes plainor water-cooled chamber, temperature-controlled shrouds, new seals for ro-tary motion, and equipment for glowdischarge, evaporation or sputtering,and electron beam heating.-D.J.P.(General Vacuum Corp., Dept. S220,82 Hicks Ave., Medford 55, Mass.)

If you are working with400 Channel Analyzers,-

of this new PackardBulletin 1032a will give

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insight intoinstrument capability.

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1362

GLASS ABSORPTIONCELLS mae KLETT

SCIENTIFIC APPARATUSKlett-Summerson Photoelectric Colorimeters-Colorimeters - Nephelometers - Fluorimeters-Bio-Colorimeters- Comparators - Glass Stand-ards-Klett Reagents.

Klett Manufacturing Co., Inc.179 East 87 Street, New York, New York

SCIENCE, VOL. 143

PERSONNEL PLACEMENT

|||||||||||| POSITIONS WANTEDIIIRIIIIIIIIIBacteriology, Bachelor of Science degree; ex-perience in medical bacteriology and pharma-ceutical research; relocation desired. Box 353,SCIENCE. 3/27; 4/3, 10

Biochemist, Ph.D., 10 years' experience researchin metabolism: some teaching; prefers Midwest.Box 346, SCIENCE. X

Chemistry Study, PSSC Physics Teacher, 30years' experience, wants suburban high school,1964-65. J. A. House, Box 2424, Williams-burg, Virginia. 3/20, 27

Clinical Chemist, Ph.D.; 7 years' experience,university hospital. Desires larger laboratorywith automation and special chemistry needs.Current salary, middle teens. Box 350, SCIENCE.

3/20, 27

(a) Ph.D. Biochemist (minor organic chemistry),postdoctoral research: alkaloids, organic nitrogencompounds; interests: natural products of syn-thesis of physiological compounds; prefers teach-ing/research. (b) M.S. Astronomy (B.S. physics;75 hours toward Ph.D. mathematical statistics);strong chemistry, psychology training; prefersuniverity teaching, data processing analyzingcomputer programming development. (c) 1964Ph.D. Plant Ecologist (natural history, botanyminors), strong statistical evolution training;honor roll throughout; prefers teaching and re-search, western location. (Please write for infor-mation regarding these and other scientists,senior and junior, in all fields.) Science Division,The Medical Bureau, Inc., Burneice Larson,Chairman, 900 North Michigan Avenue, Chicago11, Illinois. X

Ph.D. Science Education. To teach physicalscience or introductory physics. Experience highschool and college. Presently directing man-power studies. Box 349, SCIENCE. X

Ph.D. Zoologist; 7 years' experience: embry-ology, vertebrate morphology, endocrinology. De-sires teaching position with research opportu-nities. Box 352, SCIENCE. X

Plant Physiologist, Ph.D., with B.S. in botanyand postdoctoral training in biophysics, desiresacademic position, September 1964. Main in-terests: ion transport, cell physiology. PrefersWest Coast, East Coast, or western states. Box354, SCIENCE. X

Professional Journal Editor. If you need aneditor for your society publication I offer anengineering education; 35 years' experience aseditor of technical journals; intimate knowledgeof printing. I seek editorial position part-time,workng from my own office, on a bimonthly orquarterly journal, preferably engineering, elec-tronics, or physics. Box 355, SCIENCE. X

Science and Public Affairs Writer seek positionindustry, trade association, or specialized publi-cation. Information-editorial services relating toscience, technology, government, liaison in Wash-ington. Strong experience scsence news, PR,publications. Box 344, SCIENCE. X

20 MARCH 1964

CLASSIFIED: Positions Wanted. 25t perword, minimum charge S4. Use of BoxNumber counts as 10 additional swords.Payment in advance is required.

COPY for ads must reach SCIENCE 2 weeksbefore issue date (Friday of every week).

DISPLAY: Positions Open. Rates listed be-low-no charge for Box Number. Ratesnet. No agency commission allowed forads under 4 inches. No cash discount.Minimum ad: 1 inch. Ads over 1 inchwill be billed to the nearest quarterinch. Frequency rate will apply only torepeat of same ad. No copy changes.Payment in advance is required exceptwhere satisfactory credit has been es-tablished. Send copy for display adver-tising to SCIENCE, Room 1740, 11 West42 St., New York 36.

Single insertion $65.00 per inch4 times in 1 year 60.00 per inch

For PROOFS on display ads, copy mustreach SCIENCE 4 weeks before date ofissue (Friday of every week).

Replies to blind ads should be addressedas follows:

Box (give number)SCI ENCE1515 Massachusetts Ave., NWWashington, D.C. 20005

M.S. Microbiology desires teaching or researchposition. Box 362, SCIENCE. 3/27; 4/3

Ph.D. Physiology, M.S. Zoology. Desires teach-ing-research position West Coast. AvailableSeptember. Box 359, SCIENCE. X

Ph.D. Vertebrate Zoology. Experienced. Publi-cations. Available September 1964. Box 365,SCIENCE. X

Ph.D. Virologist. Broad experience. Desires aca-demic affiliation with good opportunity for re-search. Box 364, SCIENCE. X

Physical Chemist, Ph.D. Publications in surfacechemistry, electrochemistry, membranes. Someteaching. Academic or research institution. Box358, SCIENCE. X

Ph.D., Professional Engineer. Interested in posi-tion involving reviewing, abstracting, translating,and editing of scientific and engineering litera-ture. Box 348, SCIENCE. X

Researcher, Ph.D. Established in sense receptorelectrophysiology and psychophysiology; publi-cations, grants; desires research position inprogressive institution, some teaching desirable.Box 363, SCIENCE. XScientific Administrator-Administrative Officer(Col. MSC USA) and B.A. with over 10 years'experience as administrator in Army medicalresearch laboratories. Seeks position as assistantto vice president or scientific director responsiblefor university or industrial research programs.Box 361, SCIENCE. X

Translator. German/English, experienced in medi-cal literature, accepts free-lance assignments.Reasonable fees. Please write Box 4K, 67-25Dartmouth Street, Forest Hills, 75, N.Y.

Well-paid underfed (academically) professor anddepartmental chairman; too young for malnu-trition (age 39, zoology Ph.D., 1953). Assets:broad teaching background, grant experience,and program development. Liabilities: limitedreseach and publications, but wants to do more.Interests: invertebrates, cytology, cytochemistryand cytogenetics. Any offers to give up my sine-cure? 1964? or 1965? Box 351, SCIENCE. X

Young Woman desires responsible position inWashington, D.C., area commensurate with fol-lowing training; B.S. physics; M.S. mathematics;college mathematics teaching; journalistic andeditorial experience. Box 345, SCIENCE. X

II1IIIIIIIIIIIIIDIIIIIIIIIIIII POSITIONSOPEN flljlVETERINARY

BIOLOGICAL RESEARCHProgressive midwestern veterinary division of

a major international drug corporation offerschallenging growth opportunities in an expand-ing biological research and development pro-gram.

Senior Virologist-will conduct and supervisebench-level virus research associated with newproduct research and development. Will play akey role in planning future virus research pro-grams. Will supervise a research team. Thesuccessful candidate will be a Ph.D. virologistor a D.V.M. with advanced training in virologyor experience equivalent. Industrial research ex-perience is desirable but not essential.

Virologist-Will conduct bench-level virus re-search. Will supervise several junior level re-search people. Position requires recent gradu-ate D.V.M. or Ph.D. degree in microbiology orperson with equivalent in training and experi-ence. Should have a keen interest in virus re-search.

Send detailed resum6 to Personnel Manager,Jensen-Salsbery Laboratories, Division of Rich-ardson-Merrell, Incorporated, 520 West 21stStreet, Kansas City, Missouri. X

IIIIIIIIIIIIIIIIIIIIIIIIIIIIIII POSITIONS OPEN 1If 11111111111111111||||||||||||| POSITIONS WANTED|||||||||||||||

Biochemist, Bachelors degree, 7 years of medicalresearch. Desires gerontology research position.Box 301, SCIENCE. X

Biologist, Ph.D.; three books in print, manypublications, teaching experience; experience inexperimental carcinogenesis; is looking for aleading position. Box 356, SCIENCE. X

Geologist; 6 years in gas liquid systems, radio-carbon dating. Research experience and publi-cations. Desires research position in datinglaboratory at college-university, preferably insouthern or southwestern U.S. Box 347, SCI-ENCE. X

Immunologist, Ph.D., experienced teacher andresearcher; experienced also in clinical bacteriol-ogy; seeks academic appointment in East. Box360, SCIENCE. X

REGISTERED ASCP MEDICALTECHNOLOGIST

With heavy hematology background and experi-ence; salary commensurate with ability; excel-lent benefit program. Write Personnel Depart-ment,

Indiana University Medical Center1100 West Michigan Street

Indianapolis, Indiana

INVERTEBRATE ZOOLOGISTTo lead program of developing live materials forteaching application. Ph.D. desirable, with broadtraining and/or experience. Should be familiarwith culture techniques. Salary commensuratewith experience and education. Should be in-terested in improving materials available forteaching biology at all levels.

Box 366, SCIENCE

LABORATORY TECHNICIANPrefer a college graduate with a degree inchemistry; experience in clinical chemistry de-sirable; would prefer man with no militaryobligations or educational commitments; salarycommensurate with ability; excellent benefits.Write Personnel Department,

Indiana University Medical Center1100 West Michigan Street

Indianapolis, Indiana

MICROBIOLOGISTRecent Ph.D. or M.S., to conduct and superviseantibiotic and chemotherapeutic research, micro-biological assays, and diagnostic studies. Excel-lent opportunity, offering independence and goodfuture. Salary commensurate with experience andability. Good benefit program. Send resum6 to

Box 368, SCIENCE

Ph.D.'s interested in teaching college-levelcourses in mathematics, business administration,economics, humanities; eight 3-hour eveningcourses annually in Cape Kennedy area.No committee work or other administrative

duties.Write: Resident Director, P.O. Box 4393,

Patrick AFB, Florida.

WANTED-Electronics Engineer with B.S. or ad-vanced degree to develop and oversee mainte-nance of instrumentation in research laboratoriesof Dept. of Anesthesia at University of Pennsyl-vania. Liberal benefits. Write stating age, educa-tion, experience and salary requirement toPersonnel Office, 3025 Walnut Street, Philadelphia,Penna. 19104. An equal opportunity employer.

1363

UNIVERSITY OF OTTAWAFaculty of Medigine

Ottawa, CanadaAssociate Professor in Pharmacology $10,000

to $12,000 depending upon qualifications and ex-perience.Send applications to Professor M. F. Murnaghan,University of Ottawa, Faculty of Medicine, Ot-tawa, Canada.

REGISTERED ASCP MEDICALTECHNOLOGIST

With heavy chemistry background for challeng-ing work in research area; salary commensuratewith ability; excellent benefit program. WritePersonnel Department,

Indiana University Medical Center1100 West Michigan Street

Indianapolis, Indiana

Full-time Researchers in the fields ofinternal medicine, biochemistry and phys-iology desired for research-teaching pro-gram in continuing education. Salary$25,000 to $30,000 per annum.

Box 367, SCIENCE

0

DII1JIIIjDIIIIiijA PSI'TIONS OPEN j1jj1Q1jQjII IIDIIIIDIIIIIII POSITIONS OPEN | ||IIIIII|III|D1 POSITIONS OPEN |IIfIIIhBacteriologist-Management Level PositionNationally known veterinary drug manufac-

turer has a challenging job in its bacterial prod-uct section of Biological Production. Assign-ments are varied and include assisting in thesupervision of seed and media preparations,planting, growth harvesting and batching ofproducts. Supervisory ability is important. Degreein bacteriology or microbiology with job relatedexperience is necessary. Send r6sume in con-fidence to: Personnel Manager, Jensen-SalsberyLaboratories, Division of Richardson-Merrell Inc.,520 West 21st Street, Kansas City, Missouri. X

CHEMISTS-Several research opportunities areavailable to study the fate of organic pesticidesin the water environment. M.S. with analyticalor physical background preferred. Graduate studyopportunity available. Salaries to $7000. Write:Dr. Samuel D. Faust, Rutgers University, NewBrunswick, New Jersey.

GROSS ANATOMIST, Ph.D. to assist in teach-ing gross anatomy only. Twelve contact hoursper week. Research time, space and money avail-able. Opening for assistant professor, minimumsalary $7,000. Man preferred. Please send experi-ence and qualifications on initial inquiry to Dr.R. V. Gregg, Head, Dept. of Anatomy, Schoolof Dentistry, University of Southern California,Los Angeles 7, California.

MEMORIAL UNIVERSITY OF NEWFOUND-LAND. The Department of Biology invites ap-plications for a position involving teaching andresearch in the field of Vertebrate Anatomy.Teaching responsibilities will primarily involveinstruction of a course in Comparative Verte-brate Anatomy. Please send applications, alongwith curriculum vitae and names of three refereesto the Head, Department of Biology, MemorialUniversity of Newfoundland, St. John's, New-foundland.

(a) Ph.D. Physiologist, clinical, research; newCentral medical center. (b) Ph.D. Microbiologist,virology, immunology training; central univerityresearch unit; to $11,500. (c) Clinical Biochemist,special chemistries, supervisory duties; salaryequates degree, experience; Central hospitalgroup. (d) Bacteriology Research Assistants,M.S., B.S., university-affiliated institute, Mid-east. (e) B.S./M.S. Research Pharmacist; WestCoast pharmaceutical house. Faculty Appoint-ments: (f) Zoology, Genetics; M.S./Ph.D.; In-structor level; midwestern university; to $7000.(f) Ph.D. Physiologist, vertebrate mammaliantraining; teaching, research; Southwestern uni-versity; to $9500. (h) Molecular Biology/GeneralPhysiology, Ph.D./M.S.; research interests de-sirable; small southern liberal arts college. (i)Ph.D. Microbiologist; teaching, direction of grad-uate students; midwestern university. (j) Admin-istrative Dean, laboratory technology school;administration experience; technology background;start $8000. Mideast. Many other opportunitiesavailable for both junior and senior scientists.Please write to Science Division, The MedicalBureau, Inc., Burneice Larson, Chairman, 900North Michigan Avenue, Chicago 11, Illinois.

Predoctoral Assistantships and Traineeships InPhysiology. Excellent opportunities for graduatestudents leading to the Ph.D. Ample stipends andfree tuition. Training and research in biophysics,cellular physiology, endocrinology, muscle, watermetabolism, cardiovascular, gastrointestinal andenvironmental physiology. Write for details toHead, Department of Physiology, University ofIllInois at the Medical Center, Chicago, Illinois.

SENIORMICROBIOLOGIST

Recent Ph.D. or June 1964 doc-toral candidate, to conduct inde-pendent research into cellulartransport mechanisms and endo-genous resperation of baker'syeast. Strong background in inter-mediary metabolism essential. Sendyour resume to

Box 369, SCIENCE

1364

Career Opportunity In Israel For

DIRECTORPHARMACOLOGICAL SCREENING

(CE-I) Bio-Chemical or pharmaceuticalR & D speeialist to supervise testingprogram for new compounds with industrialpotential; screen newly synthesized organ-ie chemieals; organize staff and facilities.

2 YEAR CONTRACTTO ARRANGE INTERVIEW

WITH ISRAEL REPRESENTATIVECall: Mrs. L. Manofl, Director

PLAZA 2-0600COMMITTEE ON MANPOWEROPPORTUNITIES IN ISRAEL515 Park Ave., N.Y. 22, N.Y.

ENDOCRINOLOGISTSECTION HEAD

Seeking imaginative creative scientist to conductand supervise original laboratory research in de-velopment of new drugs having reproduction andgonadal hormone related actions. Should havePh.D. in physiology, anatomy, zoology, or re-lated field with research experience or thesis inreproductive system physiology. Prefer I to 3years of postdoctoral research experience. Oppor-tunity to publish. New expanding laboratoryfacilities and animal rooms. Send r6sumr to

Dr. Dorsey E. HoltkampHead, Dept. of Endocrinology

THE WM. S. MERRELL COMPANYDivision of Richardson-Merrell Inc.

Cincinnati, Ohio 45215Attending Anatomists Meeting, Denver-HiltonHotel; Federation Meeting, Palmer House Hotel

An equal opportunity employer

NATURE-SCIENCE CENTER DIRECTORTo develop new center with good facilities inthriving Southern city, B.A. preferred. Salaryrange $6000 to $10,000 depending upon quali-fications and experience. Send inquiries to Mrs.Matt R. Long, Jr., Chairman, Nature-ScienceCenter, 249 South Westview Drive, Winston-Salem, North Carolina.

Ph.D. in ChemistryInquiries invited for academic position in Chem-istry Department. Successful candidate mustenjoy teaching undergraduate chemistry. Prefer-ence given to research-oriented individual in-terested in contributing to development of plannedmaster's program in radiological health. Excel-ent fringe benefits. Write to: President, St. LouisCollege of Pharmacy, 4588 Parkview PI. St.Louis, Mo. 63110 X

Research professorship in histochemistry.Full faculty status in University MedicalSchool. Complete laboratory facilities.Direct inquiries to Office of the Dean,School of Medicine, University of SouthDakota, Vermillion.

RESEARCH VIROLOGISTSFOR EXPANDED PROGRAM

Ph.D. or M.D., recent graduates or with ex-perience. Background and interests in viraldiseases, cancer, immunology, viral interference,and cell biology. General microbiologists canqualify. Graduate students expecting degrees innear future will be considered. Interested personswrite to Mr. Robert O'Connor, Research Per-sonnel, Merck & Co. Inc., West Point, Pa.

An equal opportunity employer.

Science Educator. Science or science educationdegree, male, teaching and/or public demonstra-tion experience to conduct lecture-demonstrationprograms in secondary schools. Extensive travel.

Science Writer. Degree in science or journal-ism, experience in science or technical writingdesirable. To plan and prepare scripts for ex-hibit presentations and educational TV pro-grams on the peaceful uses of atomic energy.Write Personnel Office, Oak Ridge Institute ofNuclear Studies, Box 117, Oak Ridge, Tennessee.

An equal opportuntity employer

AMERICAN COLLEGE 3UREAVPERSONALIZED PLACEMENT i

SINCE 1690

Write Edwin Hansbrough,Science Placement - -

Serving education throughout the United States28 East Jackson Blvd. * Chicago 4, Illinois

IIIIIHIIIIIIIIIBI1IiIIIIIIIBIIIII FELLOWSHIPS ||I|I|||||||||I|II||Postdoctoral Fellowships for M.D.'s, Ph.D.'s orSc.D's in laboratory and public health aspects ofinfectious diseases. One year program, renewableyearly. U.S. citizens less than 30 years of age.Stipend $5,000-$8,000 depending upon qualifica-tions. Apply to Kenneth M. Schreck, M.D.,Dept of Microbiology, Temple Univ. MedicalSchool, Philadelphia 40, Pa.

Traineeships for Graduate Work in Pharmacology.A 4-year program of course work and researchtraining leading to the Ph.D. degree is offered.Research opportunities include the action of drugson kidney, circulation, autonomic ganglia, connec-tive tissue, behavior, metabolism, and ion trans-port. Annual stipend (U.S. citizens) of $2400 plustuition, plus $500 for each dependent. Earlyapplication strongly advised for entrance Septem-ber 1964. Detailed information on request. Write:Department of Pharmacology. School of Medicine,State University of New York at Buffalo, 15 TheCircle, Buffalo, N.Y. 14214. 3/6, 20; 4/,

The Market Plae

IIIIIIIIIID PROFMSIONAL SERVICES*IIIII

Scientifically Oriented for Expanding Industry* REC fSEND FOR AUSTIN'S 100 PAGE UFREInL INVITATION TO INDUSTRY' - -

Simply attachyour letterheadto the coupon.

Austin Economic Development Council vP.O Box 998S * Austin, Texasm- m m m- mm-

j*jj| SUPPLIES AND EQUIPMENT *

SCIENCE. VOL. 143

DISPLAY: Insertiotns must be at least 1inch in depth. Weekly invoices will besent on a charge account basis-pro.vided that satisfactory credit is es-tablished.

Single insertion $65 per inch4 times in 1 year 60 per inch13 times in 1 year 50 per inch26 times in 1 year 50 per inch

PROOFS: If copy is to be set, and proofssubmitted for approval, complete copyand cuts must be received 4 weeks inadvance of issue date (Friday of eachweek); complete plates no later than 3weeks in advance of issue date.

ULTRAVIOLET"601 FLASHLIGHT

... lighc-weig t portable source of U. V. light inthe long (3100 to 3800) A.U. ultraviolet region.Model 100 uses 3 standard D batteries. Price $65.

MED ELECTRONICS, INC.102 W. Jefferson St, Falls Church, Va. 22046

SPRAGUE-DAWLEY, INC.Pioneers in the development of theSTANDARD LABORATORY RAT.

P.O. Box 4220Madison, Wisconsin

CE 3-5318

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The new BBV High Vacuum Furnaces provide unlimited versatility with three differentseries of induction and resistance-heated models. Interchangeability of heating inserts,crucibles, susceptors and pumnping systems give wide latitudein applications for research and production.On the other hand, if you have special problems in vacuum metallurgy,we have an engineering group of ex'perienced metallurgists who will modifyone of these standard furnaces or custom design and build one which willI getyour product off the ground or wherever it's going.Read about the better things of life that BBV Vacuum Furnaces can

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NOW COUNT 100LIQUIDSCINTILLATIONSAMPLESAUTOMATICALLYAT ROOMTEMPERATUREWITH HIGHEFFICIENCYMany users of liquid scintillationspectrometers are finding thatroom temperature counting offerscertain advantages over refriger-ated operation. One of the mostsignificant is that the solubility

of the solutions encountered innormal sample preparation tech-niques is much better at roomtemperature. This means thatmore sample may be placed inthe counting vial with less chanceof quenching. The results areshorter counting times and betterstatistics.

Nuclear-Chicago ambient tem-perature liquid scintillation sys-tems routinely deliver differentialcounting efficiencies of 31% forH3 and 78% for C14 with back-grounds of 40 cpm and 30 cpmrespectively-a very favorablecomparison with refrigeratedunits. Now we have combinedthis proved performance with theconvenience of large sample ca-pacity to offer the user maximumvalue at lowest possible cost. Twoautomatic systems with 100 sam-ple capacity are available:

Model 6801. Three channel sys-

tem with dual scaler and datalister for automatic printout ofsample number, time, and counts.

Model 6804. Three channel sys-tem with dual scaler and datalister/calculator for automaticprintout of cpm and scaler ratiosin addition to sample number,time, and counts.

Both of these new systems alsofeature the same electronic andmechanical refinements that havecontributed to the excellent reli-ability of all other Nuclear-Chi-cago liquid scintillation spectro-meters. Please consult your Nu-clear-Chicago sales engineer or

write us for complete details andprices on Models 6801 and 6804.

NUC:B-4-215

NUCLEAR-CHICAGOA DIVISION OF NUCLEAR-CHICAGO CORPORATION

349 Howard, Des Plaines, Illinois 60018