MAY 1965873

FRONTIERS OF MODERN BIOLOGY

Gairdner B. Moment, Editor194 pages, paper/1962/$1.95

FROM VITAL FORCE TO STRUCTURALFORMULAS0. Theodor Benfey 115 pages, paper/1964/$1.95

THE STRUCTURE OF ATOMSJ. J. Lagowski 120 pages, paper/1964/$1.95

THE EXCITEMENT OF SCIENCEJohn Rader Platt 174 pages, paper/1962/$1.50

MAXIMIM SAFETYWITH THE WELCH

ELECTRIC STIRRER

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STIRRING RODSNo. 5230G. GLASS STIRRINGROD. Double V form, for No.5230 or No. 5230A Stirrer.

Each $0.90No. 5230M. No. 5230R. No. 5230M. MONEL STIRRING

No. 5230. ELECTRIC STIRRER ROD. Double-V form, for No.For 115 volts 50/60 cycles A.C: 5230 or No. 5230A Stirrer.

Each $58.50 Each $2.50No. 5230A. ELECTRIC STIRRER. No. 5230R. POLYETHYLENEWith stepdown transformer, for STIRRING ROD. Propeller-blade230 volts 50/60 cycles A.C. form, for No. 5230 or No.

Each $64.50 5230A Stirrer. Each $1.80

THE WELCH SCIENTIFIC COMPANYESTABLISHED 1880

Home Office: 7352 N. Linder Avenue Skokie, Ill. 60076New York Office: 331 East 38th Street New York, N.Y. 10016

clarity!Instant inspection of animals at all times.That's one of the outstanding features ofclear polycarbonate and acrylic cages madeby Lab Cages. Not just visibility but brilliantclarity! And if you require opaque cages,disposable cages, restraining cages, feed-ers, water tubes or cage racks, Lab Cagesassures you of the most up-dated line. LabCages is also exclusive sales agent forAB-SORB-DRI6 animal bedding, producedby Michael Wood Products, Inc., Garfield,N. J. It's the all-wood bedding that has beentested and approved by major laboratoriesand breeding colonies across the country.

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ZEIZEThe Zeiss Research Metallograph with new Auto-Teveling Stage combines the advan-tages of both upright and inverted (LeChatelier-type) microscopes: (1) The specimen,held from below against a precisely-aligned plane surface, is automatically positionedperfectly perpendicular to the optical axis. (2) Because you view from above, specificareas of specimens are easier to locate. (3) Immersion media can't drip onto objectivemounts. (4) All components and openings are protected from dust and dirt becausethey face downward.

Simple to operate (no specialized training required), the Zeiss Research Metallo-graph offers outstanding versatiiity: use reflected light, transmitted light, or both simul-taneously . . . select any of 3 light sources (tungsten, high-pressure mercury burner orcarbon arc with automatic feed) . . . use phase contrast for hard-to-etch specimens ...use Antiflex Objectives equipped with adjustable compensating devices to increasecontrast of low-reflectance petrographic specimens . . . use special accessories for alltypes of polarization . . . take sharp, perfectly focused 4 x 5 photomicrographs at thetouch of a button . .. use Luminar macro lenses for sharp, wide-angle and evenly illumi-nated macrographs at magnifications as low as 6.5x . . . take survey photos of samplesup to 60mm in diameter ... use 4 x 5 plate, sheet film or Polaroid 500 (35mm attach-ment also available). Power controls and drawers with fittings for accessories are in-cluded in the instrument table.

For more information, write Carl Zeiss, Inc., 444 Fifth Ave., New York, N.Y. 10018.In Canada: 140 Overlea Blvd., Toronto. COMPLETE SERVICE FACILITIES AVAILABLE.

AN AUTO-LEVELING METALLOGRAPH

THE GREAT NAME IN OPTICSATLANTA. CHICAGO. DENVER. LOS ANGELES, SAN FRANCISCO. SEATTLE. WASHINGTON. D.C.. BOSTON IN CANADA: TORONTO, MONTREAL, WINNIPEG, VANCOUVER

874 SCIENCE, VOL. 148

New Products

Analog-digital conversion handbookpresents comprehensive information onall phases of conversion, from conceptsto calibration. Diagrams supplement the73-page text; tables summarize terms,methods, and performance characteris-tics. Chapiter 1 covers "Basic elementsof conversion": definitions, terms, meth-ods of digital-to-analog (DA) and ana-log-to-digital (AD) conversions, the sam-ple and hold technique, and multiplex-ing. The remaining six chapters cover:"Measures of converter performance";"Special AD conversion techniques";"Typical converter logic"; "Basic cir-cuits; interconnection and calibration";and "Testing an AD convert." Four ap-pendices review basic digital numbers,bipolar voltages, symbols, and defini-tions. The book describes the use ofmodular circuits in construction ofconversion sysitems; modular circuitsmanufactured by the Digital EquipmentCorp. are mentioned directly. Very wellwritten and illustrated; should be a use-ful guide to the expert and a good in-troduction for the beginner.-D.J.P.(Digital Equipment Corp., Maynard,Mass.)

Circle 1 on Readers' Service card

Bibliography, Application Data Sheet245 (free), lists typical applications ofthe automatic amino acid analyzer inbiochemical, clinical, agricultural, andnutritional investigations; and refer-ences to development of basic methods.All references cited mention use of theBeckman model 120B or of similar in-struments. This 30-page booklet com-prises a subject index (pp. 1-10) and abibliography (pp. 11-30). The subjectindex is a guide to the materials ex-

The material in this section is prepared byDenis J. Prager (D.J.P.), Laboratory of Tech-nical Development, National Heart Institute,Bethesda 14, Md. (medical electronics and bio-medical laboratory equipment).The information reported here is obtained

from manufacturers and from other sourcesconsidered to be reliable. Neither Science northe writer assumes responsibility for the accu-racy of the information. A Readers' Service cardfor use in mailing inquiries concerning the itemslisted is included on page 779. Circle the depart-ment number of the item in which you are inter-ested on this card.

7 MAY 1965

amined, the majority of which pertainto the amino acid composition of na-tive protein and peptide hydrolyzates.Citations in the bibliography providedetails of the specific application.-D.J.P. (Beckman Instruments Co.,Spinco Div., 1117 California Avenue,Palo Alto, Calif. 94304)

Circle 2 on Readers' Service card

Pocket radiation alarm, model 28500Rate Alarm Monitor, is a beta-gammadetector that buzzes when the presetlevel is exceeded. Employs halogen-quenched Geiger-Mueller tube. Pro-vides 130 hours of service from mer-cury penlight cells; indicator lightshows battery condition. Four ranges:

3, 10, 30, or 100 mr/hr. Weighs 5 oz(150 g); clips to pocket. List: $99.-D.J.P. (Gelman Instrument Co., P.O.Box 1448, Ann Arbor, Mich. 48106)

Circle 3 on Readers' Service card

Automatic injector, Sage model 067,a high-speed electrochemical injectorfor repeated, reproducible injections offrom 0 to 4.5 ml of liquid from stand-ard 5- or 10-cm3 syringes. As many as

60 injections per minute. Resetting andrefilling of the syringe are automaticand rapid. Pumps against up to 5-atmback pressure. Reproducibility within2 percent of volume delivered. Injec-tion times vary depending on syringesize, volume to be pumped, and needlesize; with a 5-cm3 syringe and No. 17needle, 1.5 ml of water is injected in80 msec. Recommended for physio-logical and other applications requiringrapid, reproducible injection of pre-

cisely set volumes of liquids. Dimen-sions: 8.5 by 3.5 by 3.5 inches (22 by9 by 9 cm). Weight: 4 lb (1.8 kg).List: $145.-D.J.P. (Sage Instruments,2 Spring St., White Plains, N.Y. 10601)

Circle 4 on Readers' Service card

Surface area meter (Strohlein, fromW. Germany) measures the surfacearea of particles over the range of 0.2to 1000 m2/g by the Brunauer-Emmett-Teller nitrogen-adsorption method. The

weighed powder sample is placed inone of two matched adsorption flaskswhich are purged with dry nitrogen ina special heating block at 1500 to1 80°C to remove moisture and otheradsorbed vapors; the block can purgenine samples simultaneously. The sam-

ple flask is transferred to the measur-

ing apparatus and equilibrated withits empty twin. Both flasks are thenimmersed in liquid nitrogen, causinga monomolecular film of nitrogen toadsorb on the surface of the sample'sparticles. The resulting drop in pres-sure in the sample flask is measuredwith a differential manometer and con-verted directly to surface-area-per-gramby use of a nomogram. Total time: 30minutes. Meter comes complete withthermostated heating block, measuringapparatus, ten adsorption vessels, twomatched weighing vessels, calibrationsample, and nomogram. Operates on230-volt, 60-cy/sec a-c power. List:$2380.-D.J.P. (Fisher Scientific Co.,415 Fisher Building, Pittsburgh, Pa.)

Circle 5 on Readers' Service card

Rodent respirator, Harvard Appara-tus model 580, for adequately ventilat-ing small rodents (mice, rats, ham-sters) where small stroke-volumes atfast rates are needed. The positive-pressure type cylinder-pump deliversair or nonexplosive gas mixtures to theanimal under pressure through a three-way valve. At the end of the intakestroke, the valve changes and the elas-ticity of the lung produces expiration;exhaust gas can be collected or re-cycled. Independent controls canchange both rate and volume whilethe pump is running. Piston-mechan-ism is such that the cylinder com-pletely empties after each stroke, re-gardless of the stroke volume. Ratecontinuously variable from 30 to 200strokes per minute, using electronicmotor control. Luer-Lok syringe bar-rels are used as the cylinder; a Delrinpiston with 0-rings ensures a tight mov-ing seal. A 20-cm3 barrel producesstroke volumes adjustable from 0.5 to10 cm3 per stroke; with 10-cm3 barrel,volumes are adjustable from 0.2 to 5cm3 per stroke; a 20-cm3 barrel isnormally supplied. Pistons and barrelseasily changed in the laboratory. Out-put fittings are 3/16 inch in diameterand fit standard plastic tubing of 3/16-inch bore. Dimensions: 12 by 6 by 8inches (30 by 15 by 20 cm). List:$250.-D.J.P. (Harvard Apparatus Co.,Inc., Dover, Mass. 02030)

Circle 6 on Readers' Service card

875

TNE. MACMILLAN COMPANYProfessional and TechnicalBooks Available now - .

MUSCLE STRUCTURE ANDFUNCTIONContains papers presented at the meet-ing in Alberta in 1964. This is a bookof new concepts covering the wholefield of muscle function.Edited by W. M. Paul, et al. $15.00

o GENETICS TODAYProceedings of the 11th InternationalCongress, The HagueEdited by S. J. Geerts

3 Volume SetPre-publication price $36.00

(After May 31st, will be $45.00)

W THE PHYSICS OF THE EARBy T. S. Littler, King's College Hospital,Director, WERNHER RESEARCH UNITON DEAFNESSWritten as a textbook for physics stu-dents. $12.00

o THE USE OF RADIOACTIVEISOTOPES IN TUBERCULOSISRESEARCHProceedings of the International Sym-posium, PragueEdited by J. F. Pasquier, et al. $10.00

o SPEECH DISORDERSMultisensory Techniques for RemedialEducation in Disorders of Speech Lan-

guage and Psycho-neural Motor SystemBy Suzanne de Parrel $12.00

j- DRUG ADDICTION IN YOUTHEdited by E. Harms $9.50

SECOND INTERNATIONALPHARMACOLOGICAL MEET-ING, PragueEditor-in-Chief: H. RaskovaEleven volume set $115.00

W ELECTROPHYSIOLOGY OFTHE HEARTProceedings of an International Sym-posium held in MilanEdited by B. Taccardi and G. Marchetti

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1 DYNAMIC CIRCUIT THEORYBy Hugo K. Messerle, Visiting Profes-sor in Electrical Engineering, CornellUniversityWritten to serve as a text for an in-troductory course in electro-mechanicalenergy conversion and linear feedbackcontrol systems. $15.00

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INDEX TO ADVERTISERS-7 May 1965

Academic Press .. .Ace Glass, Inc..................Addison-Wesley

Publishing Co., Inc............Allied Chemical.American Optical Co............Annual Reviews, Inc.............Antioch Press.Appleton-Century-Crofts.Applied Physics Corp...........Atomic Accessories, Inc..........

Baker, J. T., Chemical Co.... 868,Bausch & Lomb ................Beckman Instruments, Inc., Sci-

entific and Process Instru-ments Div..................

Bel Art Products ...............Blackstone Ultrasonics, Inc.......Blicknan, S., Inc................Brinkmann Instruments, Inc. ......Bronwill Scientific ...............Burgess Publishing Co...........

Clay-Adams, Inc................Cold Spring Harbor Laboratory ...Coleman Instruments Corp.......Columbia University Press .......Consultants Bureau .............Cosmic Radiation Labs, Inc..

Davis, F. A., Co................Digital Equipment Corp.........Disposable Laboratory Cages, Inc.

Eastman Chemical Products, Inc.E-C Apparatus Corp............Edmund Scientific Co..Electronic Associates, Inc.........E & M Instrument Co., Inc.......

Falcon Plastics.Farrand Optical Co., Inc.........Fish-Schurman Corp............Four Continent Book Corp.......

General Motors ResearchLaboratories.

Glas-Col Apparatus Co...........

Hacker, William J., & Co., Inc. ...Harvard Apparatus Co., Inc.......Holden-Day Inc..Honeywell.Houghton Mifflin ...............Hyland Laboratories ............

Instrumentation Specialties Co.....International Equipment Co.......

Jarrell-Ash Co..................

Keithley Instruments ............Kirschner Manufacturing Co..Klett Manufacturing Co., Inc.Kontes Glass Co................

Lab Cages, Inc .......... 873

Lea & Febiger .......... 723

Leitz, E., Inc........... 736

London Co........... 726

876

Macmillan Co..Maryland Plastics, Inc.,

Econo-Lab Div..............Matheson Co., Inc..............Matheson, Coleman & Bell, Div.

of Matheson Co..............McGraw-Hill Book Co., Inc......Melabs ........................Millipore Filter Corp...........

Nalge Co., Inc..National Agency for Inter-

national Publications, Inc.......Nikon Inc., Instrument Div.......Nuclear-Chicago, Div. of

Nuclear-Chicago Corp........Nuclear Data Inc...............

Oxford University Press .........

Pace Engineering Co..Percival Refrigeration and

Manufacturing Co.............Pergamon Press, Inc.............Perkin-Elmer Corp .. 732,Pharmacia Fine Chemicals Inc.Photovolt Corp.................Picker Nuclear .................Polaroid Corp..................Prentice-Hall, Inc...............Princeton Applied Research Corp.Professional Tape Co., Inc.......

Royson Engineering Co. .........

Sage Instruments, Inc............Sanborn, Div. of Hewlett-PackardSanders, W. B., Co..............Schleicher, Carl, & Schuell Co. ...Scientific Glass Apparatus Co., Inc.Scientific Industries Inc..........Siemens America, Inc .. 718,Sorensen, a unit of Raytheon Co. 709,Sorvall, Ivan, Inc...............Southern Precision Instrument Co.Spectrolab, Div. of Textron

Electronics, Inc...............Statham Instruments, Inc.........

Taurus Press, Inc..............Technical Measurement Corp.....Technicon Instruments Corp......Texas Instruments, Inc...........Thomas, Charles C, Publisher 706,

University of Michigan Press .....University of Wisconsin Press .....

Vanguard Instrument Corp......Van Nostrand, D., Co., Inc......694 Varian Associates ..............

876

841698

853835846838

842

870711

837702

731

862

867721856704838717735864712858

867

862714683866839864719710703861

850857

836738697729707

862847

730859701

Welch Scientific Co. ............ 873Wiley, John, & Sons, Inc. .... 686-689Williams & Wilkins Co. 845, 852, 856Worthington Biochemical Corp. ... 844

Year Book Medical Publishers, Inc. 851

Zeiss, Car), Inc . ................ 874

SCIENCE, VOL. 148

I

I

RecordersChoice of one to six recording chan-nels, 12 fixed-speed or continuouslyvariable speed chart drive, rectilinearor curvilinear ink writing. Operationalsimplicity of all E & M precision equip-ment permits immediate use by per-sonnel untrained in electronics.

TransducersE & M provides Transducers forrespiration-rate, depth; air flow; im-

pedance pneumography; plethysmogra-phy, rheography; muscle pull-smooth,skeletal, cardiac; gut motility; pressure;blood pressure-direct and indirect;blood flow; circulation times; oxygentension; pulse -rate, contour, velocity;electrocardiography; heart rates; heartsounds; electroencephalography; rheo-encephalography; glandular secretions;galvanic skin response; temperature;electromyography; and others.

E & M INSTRUMENT CO., INC.Box 14013 * 6030 England Street * Houston, Texas 77021

Instrumentation for Research and EducationSend for 32 page, fully-illustrated catalog, #105.

Circle "a" on readers' service card

E & M's Newest Pressure TransducerThe Linear-Core.M Model P-1000

The first in a wholly new series of force and pressure transduceris now available, featuring wide range, low volume displacemenand a high overload factor. It reduces the per channel cost apressure recording, since no pre-amplifier is required. Designeto operate into the PHYSIOGRAPH, the Linear-CoreTM Model P.l00provides maximum sensitivity of 4 mm. Hg/cm pen deflection. Thioverall range is from-100 to over 1000 mm.Hg. Volume displacement: 0.7 mm' per 100 mm.Hg. Maximum overload: 4000 mm.HBInternal calibration: 10 and 100 mm.Hg. Linearity and hysteresis±-0.5% of selected range. E & M Instrument Co., Inc., 6031England St.. Houston. Texas 77021. Circle "b" on r. service car

E & M's New Isotonic MyographLinear displacement transducer for smooth muscle and otherconstant tension studies: no internal hysteresis or friction;minimal system inertia; internal calibration. E & M InstrumentCo., Inc., 6030 England St., Houston, Texas 77021

Circle "c" on readers' service card

U_ __l |||||||||||||| O IIONS WANTED |||||PO I ....

I||||||||||||||||||||||||||'POSITIONS WANTED-IID||||||||||(a) Biochemistry Ph.D.; Dept. supervisor in largehospital, university faculty member, research,public health experience; desires administrativeresearch appointment. (b) Psychology Ph.D., seekselectrophysiology research position. For detailswrite Woodward Medical Personnel Bureau, 195North Wabash Avenue, Chicago, Illinois 60601.

x

Cytologist, Ph.D. Electron microscopy, botany,zoology. Publications. Teaching and research po-sition. Box 164, SCIENCE. X

Ph.D. Agricultural Education, special interest intechnology and the history of science, 6 yearsof teaching experience at secondary and juniorcollege levels in biology. Available August 1965.Box 163, SCIENCE. 5/21

Ph.D. Microbial Genetics. Experience in bio-chemical and physiological aspects of genetic andplant cytology. Seeks research and/or teachingposition. Box 162, SCIENCE. X

Physiologist/Pharmacologist. D.V.M. Ph.D. Teach-ing, research background in medicine. Prefersappointment in progressive arts and sciences orengineering college or medical school. Box 154,SCIENCE. X

(a) Ph.D. Zoologist-Physiologist (biochemistry,microbiology minors); experimental morphology,embryology, genetics training; arthritic, metabolicpostdoctoral research; industrial toxicology ex-perience. (b) M.A. Systematic Zoology (parasitol-ogy, helminthology, medical entomology minors);research, teaching experience; desires positionwith potential in zoological sciences. Please writeScience Service, The Medical Bureau, Inc., 900North Michigan Avenue, Chicago, Illinois 60611.

x7 MAY 1965

PLANTPHYSIOLOGISTTHE AGRICULTURAL

RESEARCH DEPARTMENTOF

OLIN MATHIESONCHEMICAL CORPORATION

seeks a Ph.D. with minimum 5 years'experience in herbicidal research, toptan and conduct screening and smallplot field-testing of herbicides, growthregulators and fertilizers.

Please send re'sume and startingsalary desired, in confidence to:

Business Manager

SQUIBB INSTITUTEFOR MEDICAL RESEARCH

New Brunswick, New JerseyAn equal opportunity employer

877

Unmatched:* Versatility* Reliability* Simplicity of operation

THEPHYSIOGRAPHthe complete physiological

recording system

rersonnetPlacement

I

Magnetobiologist, Ph.D. Experimental medicine,1965. Strong biology, physiology, physics, micro-climatology background. Experience in bioclima-tology. Fluent in Dutch, Spanish, German,French. Prefers magnetobiological research. Box158, SCIENCE. X

Microbiologist-Immunologist, Ph.D. Broad train-ing and interests. Research, clinical, and teachingexperience. Desires western United States, chal-lenging position with opportunity for professionalgrowth. Available immediately to 1 July. Box159, SCIENCE. X

Vertebrate Zoologist, Ph.D. Fifteen years of col-lege and university experience. Seeks teaching-research position for one year (1965-1966) or ona permanent basis. Box 160, SCIENCE. 5/14

||||||||||||||||POSITIONS OPEN 1111111111111111(a) Ph.D. Applied Mathematics, interdisciplinaryand independent research; Midwest. (b) M.S./Ph.D. Psychology/Biostatistics, human factor ex-periments; Mideast. (c) M.S. Virologist, publichealth investigations; West; to $11,000. (d) Ph.D.Bacteriology, clinical, East; to $15,000.Faculty Appointments: (e) Chairman, Pharma-cology department; Northwestern university; (f)Chairman, Education-Psychology; small collegeadministrative experience; Mideast. (g) BiologyInstructor, Southeastern junior college. (h) Chem-istry Instructor; Northeastern college. Many othersat Science Service, The Medical Bureau, 900North Michigan Avenue, Chicago, Illinois 60611.

x

Assistant Head, Dept. of Micro-Biology & Im-munology. Leading, University-Affiliated, N.Y.C.Hospital & Medical Center. Once every so oftena scientist comes across a stimulating position de-signed to tax his imagination, talent, & resource-fulness. Such a position now exists if you havea Ph.D. in Physical Biochemistry, Immunochem-istry or Colloid Chemistry. Opportunity for ad-vanced research in addition to administrative andsupervisory responsibilities. Excellent salary pluscomplete benefit program. Write, stating salaryto: Montefiore Hospital & Medical Center, 210thSt. & Bainbridge Ave., Bronx, NY 10467 Att: Mr.Freeman, Personnel Dept.

...................,,,,,.|§,,,~~~~~~~~liiiiiiiiiiiUllilM..-

X

iiiiiiiiiiiiiiiiiiiiifill lifilliffill lifil 111111

Applied MathematiciansOperations AnalystsApplied Physicists

CAREER APPOINTMENTS

Exhibit A

Achievement is the most con-

clusive evidence of capability.At Booz-Allen Applied Re-

search, achievement takesmany forms, covers manyfields, and is manifest in thesuccessful completion of morethan 3,000 projects for 1,200clients. State-of-the-art tech-nical assignments in astro-nautics, communications,computer and data handlingsystems, feasibility analysis,operations analysis, transpor-tation, and numerous otherproblem areas of equal com-

plexity have demonstratedboth the breadth and the depthof our capability.

Continued achievement hasmeant strong, steady growth. . . inevitably accompaniedby demands for additional staffmembers to help us meet new

challenges. A career appoint-ment at BAARINC offers ex-

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BOOZ * ALLENAPPLIED RESEARCH Inc.135 South LaSalle StreetChicago, Illinois 60603New York * WashingtonCleveland - ChicagoLos AngelesAn equal opportunity employer i,

illlllllilllllllPOSITIONS OPEN lllllllllllIiAPPLIED RESEARCH PHYSICIST

VANCOUVER, CANADAFor head of a department of a contract re-

search institUrte. Responsible for conceiving, plan-ning, directing, and reporting research progransatid for applying researcih to industrial operations.Ph.D. with at least It) Nears' experience, prefer-atbly in industry. Salary to $15,()(t per year.Must be conceptual aild capable of administerin-

at research grotp.Send ftill detatils on edticatioln and experiencc

to: Director, British Coluimbia Research Council,Vancouver 8, Canada.

(.i) Biochemist, nianage private cliniical lab. wv.

1X tecls; E: $15.1)00. (b) Asst. Prof. Microbiology,veteritiarY teach arid research at ciniv; MidW;$12,1110. (c) Toxicologist, clinical. teaching, re-

search dtities; lairge uiniv. hosp: E: SI 1,1)01). (d)Parasitologist, stipv. R&D veterinary prod: largemfr: niew researchl facilities; MidW; $12,t)000. (e)Nlicrobiologist, teach basic scicnces, developtirants program; chiropody college; $tt),1)000. WriteWoodward Mledical Personnel Btireau, 185 NorthWabasih Avenuie, Chicago, Ilinois. 60601.

Profestioital Placerttert( Service for- 6,8 Ye'OrS.

PHARNIACOLOGISTPHARNIACEUTICAI, CHEMISTAI)MINISTRATIVE DIRECTOR

Permrianent St:tff PositionsPtresti-e, Challenge :nd Adsvancement

U.S. P'HARMACOI'EIANess Yolnk City

Openings for Pharmacologist (Ph.D. or M.D.).Ass'starit Pharritacologist, Pharmaccutical Chcitiist,and Administraitive Director. Experiemnce in drurgevalutatitioi or drtig standards preferredl. Pliar mai-cetitCal backgrouind airid writing skill essential.Salars conimenstirate wsith experience arid train-ing

All inlquLiries held conifidetitial.

Addlress: Dr. George 13. Beal, Chairmani,U.S. Pharmacopeia, 46 Park Avenue,New York, N.Y. 10016

SCIENlIFIC EDITOR AND WRITFERTo edit manuscripts for suibmissioni to scienitificjournails, to help cdit ard ptiblish scicilti;c ness-letters, and to write seniipopurlarr articles explaini-ing the backgrotiutid of cuirrent researchi it theatmospheric sciencces to interested lay itrcii arildscientists in other fieldIs.Write Pertsomitel Deprartmennt. National Center forA tmosl)heric Research, Botilder, Colorado 80301

5 7. 14, 21

SENIOR BIOCHENIISTPh.D. in bioclerilistt y atrd experience in ding

nostic procedltrres. Excellent facilities tind anit-ple opportunity to cengage in individtual onicooperative researclh in additiotn to (lit ecting-staff in clinicarl labor aitories.Wr-ite to: Per-sonnel Dir-ector-

St. Joseph Niercy HospitalAnn- Arbor-, Michliign 48108

illllllllllllll POSITIONS OPEN ||||||||||||||BIOCHEMIST

Challenging0opportulnity for indlividual withM.S. in biochemiiistr-y to supet-vise chemistrystaff in large hospital clinicatl labor atories. Ex-pereience in (liagnostic biochemistry desirable.IndividtLzal and cooperative reseat ch pirojectsavailable. Box 138, SCIENCE.

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MIONASH UNIVERSITYMelbourne, Australia

Department of Zoology andComparative Physiology

Applications atre invitedI for appoinitmncit zis:SENIOR LECTURER OR LECTURER IN

EMBRYOLOGY OR ZOOLOGYThe Departtmlenit is well eqtuipped and its 15ac.idcnric membrers are engaged in a widlevarictv of work in the fields of inivertcbratcand vertebrate physiology, ecology arid bc-haviotur as Nwell as gencetics and vertebratepal,acontology.Salary ranges: Selior Lcctuircr £ A3.25t--£A3,800; Lectuirer £A2,400£-EA3l150 p.a.Nsith stiperaniitiuatioir provisioli onl the F.S. S.U.basis.Benefits: Ftill travcIling expetises ftOi a11 ap-poititcc aridl family; removal allowance: re-patriatiotn aftcr three years' appointment ifdesired; subsidised lhotisinig pltis avatilabilityof lotins for ltome ptircilasc; (nc year's StuLdyleave after six years' service, pro r atal afterthirce years, with prosvisioi for finlanlcial als-sistance.F tirtlier genreralt iniformationi is avaiableI froithe Rcistrar of the Uniiversitv, P.O. Box 92,Clayton, Victoria, Auistralia, or the Sccretary-Gene al, Association of Commonwcalth Urli-versities, Marlborolgh HouIse, Pall Mall, Loui-don S.W...Eiquiries concerniing thc lDepart-merit should be addressed to Professor A. J.Matrshall.Closing date: 28 May 1965

F. H. JOHNSON, REGISTRAR

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SCIENCE, VC)L. 148

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