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LAND AND WATER USESpecial Reference to Mountain & Plains Regions

Wynne Thorne, EditorAAAS Symposium Volume No. 73. May 19636" by 9", 364 pages, references, index, $8.00(AAAS members' cash order price $7.00)

Arranged by the AAAS Section on AgricultureThis symposium volume reports papers by leadersin research, and policy discussions relating to thenation's land and water resources, presented atthe AAAS meeting in Denver, Colorado, in De-cember 1961.The volume centers on problems associated withthe increasing competitive demands for use ofpublicly owned lands. The historic uses by live-stock and timber processors are being challengedby groups concerned with recreation, wildlife, andwater production. Adjustments in public land usein relation to uses of adjacent or intermingledprivately owned lands need further considerationif the total benefits from these resources are tobe maximized. These and other problems of landand water are explored by recognized leaders inthe field.

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5 MARCH 1965

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Peristaltic pump, model 4912 A, LKBInstruments, Inc., is specially designedfor analytical techniques (such aschromatography and electrophoresis)which require a steady and prolongedflow of liquid. It is self-priming, pro-duces minimal pulsation, has no deadvolume, and has a closed system forsterility; it pumps a wide range of ma-terials. A wheel with six rollerssqueezes two short lengths of tubing,causing a steady flow of liquid throughtwo separate systems. High flow-con-stancy, with fluctuations < 0.1 percentin 24 hours, is claimed. A synchronousmotor runs at 24 rev/min on 60 cy/secpower (20 rev/min on 50 cy/sec); theexit shaft speed is continuously variablefrom zero to 6 rev/min. Tubing diam-eters (inside) from 1/16 to 5/32 inch(1.6 to 4.0 mm) can be used, produc-ing flow rates from 0 to 96 ml/hr andfrom 0 to 468 ml/hr (0 to 80, 0 to 390ml/hr, 50 cy/sec). Dimensions: 12 by9.25 by 5.5 inches high (31 by 23 by13.5 cm). Units available for 115 or

220 volts; 50 or 60 cy/sec. Suppliedwith 5-feet (1 .5-mi) Tygon tubing with1/16-inch bore, and connectors.-D.J.P. (LKB Instruments, Inc., 4840Rugby Ave., Washington, D.C.)

Circle 1 on Readers' Service card

Hydraulic press for pressing, pel-letizing, and compacting KBr for in-frared analysis. Dimensions: 20 by 8.7by 13.7 inches deep (51 by 22 by 35cm). Weight: 230 lb (104 kg). De-livers total pressure of 67,200 lb overa 1-inch stroke. The open "C" shapearound the work area provides 250deg of access; maximum vertical ac-

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 1169. Circle thedepartment number of the item in which you areinterested on this card.

1174

cess, 6.1 inches. Lower cylinder (6-inchdiameter) rises 1 inch to engage thework and press it against a hardenedsteel platen (diameter, 1.5 inches) above.Stainless steel pump-handle mountedabove the press. Machined parts, stain-less steel or heavy chrome or nickelplating; main casting, nodular iron. Oilseal around cylinder consists of fivesynthetic rubber gaskets for reliability.List (model 30C): $575.-D.J.P.(Limit Research Corp., 557 Post Road,Darien, Conn.)

Circle 2 on Readers' Service card

Table-top hyperbaric chamber, for

investigating the effect of high pressureon rats, provides an interior work space6 inches (15.2 cm) in diameter by 16

inches (41 cm) long; of steel and weigh-ing 54 lb (24.5 kg), it is rated for pres-sures 150 lb/in.2 (10.5 atm) gage.Although primarily for use with hyper-baric oxygen, the small chamber per-mits economical studies with rare gases(xenon, kryton). A special regulator,with a gage indicating pounds persquare inch, attaches to any standardoxygen cylinder. The 6-inch quick-opening door seals the chamber in 2

seconds without use of wrenches. Up to15 leads from various transducers can

be connected to terminals inside thechamber; leads pass through the cham-ber wall to an external terminal board

by way of low-resistance feed-throughsso that variables (EKG, EEG, tempera-ture, blood pressure, respiration rate)can be monitored. Two 1/8-inch (3.2-mm) internal diameter copper tubes,passing through pressure fittings, permitcollection of gas and blood samplesdespite pressure. One may look intothe chamber through a 6-inch tempered-glass observation port in the top. De-pressurization and ventilation by means

of a 4-inch pressure gage and a meterindicating flow in liters per minute.-D.J.P. (Hyperbaric Oxygen TherapyDiv., Bethlehem Corporation, 225 W.Second St., Bethlehem, Pa.)

Circle 3 on Readers' Service card

Ultraviolet (UV) interference-filterset, Optics Technology Set No. 8, in-cludes seven Monopass interferencefilters spaced at every 20 mu from230 to 350 m/A, plus special UV-block-ing and UV-transmitting, visible-blocking, glass filters. Each UV Mono-pass filter transmits only a narrow bandof wavelengths, rejecting all othersfrom x-ray to x-band; this permitshighly sensitive spectral measurements.Peak wavelengths for the filters arenominally 230, 250, 270, 290, 310,330, and 350 mMu + 10 m,nA. Spacingbetween adjacent filters is 20 ± 5 m/i.Passband characteristics include half-widths from 6 to 10 percent of peakwavelengths; peak transmissions of 10to 22 percent. Sideband transmissionis less than 0.1 percent on the short-wavelength side and less than 0.4percent on the long-wavelength side.A long-wave-pass glass filter transmitsthe visible spectrum and blocks theUV; valuable in fluorescence studiesfor blocking UV excitation while trans-mitting visible fluorescence to the de-tector. Cut-on wavelength is 400 m,u;cut-on slope, 7 percent, nominal. Sec-ond glass filter of black glass transmitsUV and blocks the visible spectrumwithin 0.001 percent. It may be usedseparately as a UV bandpass filter orin series with a Monopass interferencefilter to optimize visible-spectrum re-jection. An accurate transmissioncurve, which includes a 10:1 scale ex-pansion for both sidebands, is sup-plied for each filter. Curves laminatedin heavy, durable plastic and boundin a volume. Filters (1 by 1 by0.080 inch) packed in a leatherettebox. List: $495.-D.J.P. (Optics Tech-nology, Inc., Palo Alto, Calif.)

Circle 4 on Readerse Service card

Short path-length, flow-through cu-vette permits direct reading of opti-cally dense samples without dilution.An accessory for the Bausch & LombSpectronic 20 colorimeter, this cuvetteprovides path lengths of 0.1, 0.2, 0.5,and 1.0 mm by means of precisionstainless steel shims (accurate to 0.01mm) placed between the windows ofthe cuvette. Sample is sucked into thesplit in the shim by vacuum. An aver-age of four samples per minute canbe run, with photometric repeatabilityof 0.2 percent (95-percent confidencelimits). Cuvette alone is interchange-able with the standard flow-throughcuvette. List: $125.-D.J.P. (Bausch &Lomb Inc., Rochester 2, N.Y.)

Circle 5 on Readers' Service cardSCIENCE, VOL. 147

What does Maryann mean to you?Maryann is your representative at our place. As

such, she channels your orders, your requests for in-formation, your problems-and even your complaints,if such there be-to the right people here. And shegets action.

You may wish to remember all this the next timeyou need biochemicals of the highest quality at com-petitive (or Better) prices. Specifically, remember it ifyou're a user of nucleotides, nucleosides and bases, anti-metabolites, amino acids, sugars or sugar phosphates,sulfur or sulfhydryl compounds, or other biochemicalcompounds. Many, many of our products are alsoavailable in tagged form. (Do you have our catalog?)

In addition to this service and the wide selection of

5 MARCH 1965

biochemicals, we're proud of the quality of our com-pounds and the steps we take to assure you of thisquality. With each and every shipment you get a de-tailed Product Analysis Report covering the specificmaterial you receive. Also (when appropriate) a radio-chromatogram with 0.5% sensitivity. This preciseevidence of quality enables you to use all your timedoing research.You can leave the quality control to us.

So, we conclude: when you want one of our com-pounds-or information about them-remember thatMaryann means "service" to you. Please feel free tocall her collect at 914-359-2700.

Schwarz BioResearch, Inc. ZZZOrangeburg, New York 10962

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MECHANISMS OF HARD TISSUE DESTRUCTIONEditor: Reidar F. Sognnaes, Dean, School ofDentistry, Center for the Health Sciences, Universityof California at Los Angeles

AAAS Symposium Volume No. 75, 1963. 776 pages, 430illus., one color plate, references, indexes. $13. AAAS mem-bers' cash orders, $11.

ContentsC. M. Yonge: Rock-Boring OrganismsT. F. Goreau and W. D. Hartman: Boring Sponges as

Controlling Factors in the Formation and Maintenanceof Coral Reefs

M. R. Carriker, D. B. Scott and G. N. Martin, Jr.: De-mineralization Mechanism of Boring Gastropods

R. F. Sognnaes: Dental Hard Tissue Destruction withSpecial Reference to Idiopathic Erosions

C. R. Barnicoat: Attrition of the Hypsodont ToothA. L Darling: Microstructural Changes in Early Dental

CariesE. Johansen: Ultrastructural and Chemical Observations

on Dental CariesJ. A. Gray and M. D. Francis: Physical Chemistry of

Enamel DissolutionP. H. Keyes and H. V. Jordan: Factors Influencing the

Initiation, Transmission, and Inhibition of DentalCaries

W. V. Mayer and S. Bernick: Effect of Hibernation onTooth Structure and Dental Caries

1. Reichborn-Kjennerud: Dento-Alveolar Resorption inPeriodontal Disorders

S. N. Bhaskar: Bone Remodeling during Dental Eruptionand Shedding

R. J. Goss: The Deciduous Nature of Deer AntlersF. C. McLean and R. E. Rowland: Internal Remodeling

of Compact BoneM. R. Urist, N. S. MacDonald, M. J. Moss and W. A.

Skoog: Rarefying Disease of the Skeleton: Observa-tions Dealing with Aged and Dead Bone in Patientswith Osteoporosis

J. Jowsey: Microradiography of Bone ResorptionR. W. Young: Histophysical Studies on Bone Cells and

Bone ResorptionN. M. Hancox and B. Boothroyd: Structure-Function Re-

lationships in the OsteoclastJ. T. Irving and C. S. Handelman: Bone Destruction by

Multinucleated Giant CellsL. F. Belanger, J. Robichon, B. B. Migicovsky, D. H.Copp and J. Vincent: Resorption without Osteoclasts

G. Nichols, Jr.: In vitro Studies of Bone ResorptiveMechanisms

B. K. Forscher and D. V. Cohn: In vitro CarbohydrateMetabolism of Bone: Effect of Treatment of IntactAnimal with Parathyroid Extract

C. M. Dowse, M. W. Newman, K. Lane and W. F.Neuman: Metabolic Action of Parathyroid Hormoneon Rat Calvaria

P. Goldhaber: Some Chemical Factors Influencing BoneResorption in Tissue Culture

G. N. Jenkins and C. Dawes: The Possible Role of Chela-tion in Decalcification of Biological Systems

C. M. Lapiere and J. Gross: Animal Collagenase andCollagen Metabolism

British Agents: Bailey Bros. & Swinfen, Ltd., Warner House,48 Upper Thames Street, London E.C.4

American Association for theAdvancement of Science

1515 Massachusetts Avenue, NWWashington, D.C. 20005

SCIENCE, VOL. 147

I1

11j76

(a) D.V.M. toxicology, pharmacology background;teaching, research experience; publications; de-sires senior industrial/academic opportunity. (b)Ph.D. Microbiology (biochemistry minor); clinical,research experience; prefers same/teaching. Forinformation please write: Science Service, TheMedical Bureau, Inc., 900 North Michigan Ave-nue, Chicago, Illinois 60611. X

Geology Instructor. Desires permanent opportun-ity to teach geology and related courses. M.S.;2 years of college teaching. Box 80, SCIENCE. X

Pharmacologist (Ph.D.) with administrative andlaboratory experience seeks adimnistrative posi-tion. Box 82, SCIENCE. 3/12

Physiologist, Ph.D. Academic experience, publi-cations. Endocrinology, GI, biological transport.Desires professional school or research appoint-ment, September 1965. Box 83, SCIENCE. X

Physiologist, 41, Ph.D. (zoology). Teaching andresearch background: mammalian, endocrine,cellular. Desires position in zoology department,September 1965. Box 84, SCIENCE. X

Translator, B.S.Chem. German-English. Promptservice. Box 74, SCIENCE. 3/5

Virologist, M.S. Experience in tissue culture,immunology. Prefers research position, Midwest.Box 79, SCIENCE. 3/12

Virologist, Ph.D., desires teaching and/or re-search position. Research, teaching, and indus-trial experience. Publications. Box 85, SCIENCE.

x

(a) Microbiology Ph.D., Senior Virologist withpharmaceutical firm; tissue culture experience;desires administrative commercial appointment.(b) Bacteriology Ph.D., Clinical pathology pro-fessor at medical school; prefers academic orresearch opportunity. Write: Woodward MedicalPersonnel Bureau, 185 North Wabash Avenue,Chicago 60601. X

(a) M.S./Ph.D. Clinical Chemist; head section,research, teaching; academic affiliation available;East; $13,000. (b) Ph.D. Microbiologist/Virologist;immunology training; university appointment pos-sible; New England research institute. (c) Ph.D.Pharmacologist, drug metabolism studies; Centraldrug firm. (d) Bacteriology Technician, experi-enced; Midwestern company.Faculty Appointments: (e) Ph.D. Histologist,electron microscopy training; Central university.(f) Biology Instructor; botany, ecology, zoologylab; small mideastern college. (g) InvertebrateZoologist; ecology/physiology training; southwest-ern college. (h) Ph.D. Medical Mycologist, teach-ing, research; southeastern university. Pleasewrite Science Service, The Medical Bureau Inc.,900 North Michigan Avenue, Chicago, Illinois60611. X

RESEARCH PHARMACOLOGISTHazleton Laboratories, a leading independent

company specializing in the life sciences, needsa pharmacologist (B.S. or M.S.), with a mini-mum of 5 years' experience, preferably in thepharmaceutical industry.

Please send r6sum6 to:Hall A. AcuffAssistant Personnel ManagerHazleton Laboratories, Inc.P.O. Box 30Falls Church, Virginia(Suburban Washington, D.C.)

An Equal Opportunity Employer

RESEARCH OPPORTUNITYImmediate vacancy with medical college locatedin northwestern Philadelphia for chemist or bio-chemist to assist with research project in lipidmetabolism. Position requires M.S. or B.S. degreewith previous research experience. Salary depend-ent on background and qualifications. Excellentbenefit program. Write

Box 58, SCIENCE 2/26; 3/5

5 MARCH 1965

r

MELPAR

RESEARCHIMM EDIATEOPEN I NGS

Organic & Analytical ChemistsInstrumentation in the fields ofvisible, ultra-violet, and infraredspectroscopy, flame photographyand gas chromatography for chem-ical analytical instruments.Analytical or Physical ChemistExperienced in spectroscopy andable to operate a Mass Spectrom-eter. Position at Cape Kennedy,Florida.

Micro-BiologistPerform experiments with micro-bial production of hydrogen andthe analysis of the data,. Trainingin biochemistry and familiar withthe influence of genetic alterationor enzyme capability. Advanceddegree.Molecular BiologistTraining and experience in nucleicacids. Conduct studies on the hy-bridization of nucleic acid frombacteria, virus and animal tissue.Ph.D. or equivalent desired.

Senior Infrared PhysicistInfrared system design of detec-tors, optical systems and special-ized infrared techniques.Bio-PhysicistConduct research in biophysicalaspects of virus-cell interaction.Advanced degree desired.

Write To Clarence EndsleyProfessional Placement

MELPAR-NICA SUBSIDIARY OF WESTINGHOUSE AIR BRAKE COMPANY

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ACADEMIC BIOCHEMIST-young, training andresearch interests, publications, in field of enzymesor nucleic acid metabolism, for budget line posi-tion on staff in medical school-graduate schooldepartment. Teaching load moderate; researchfacilities good. Twelve-month appointment. Salary$11,000-$14,000, depending on experience. WriteChairman, Department of Biochemistry, LSUMedical School, New Orleans, Louisiana 70112.

Positions OpenGRADUATE ASSISTANTSHIPS IN BIOCHEM-ISTRY: Teaching and research appointments lead-ing to Ph.D. Available for academic year 1965-1966. Wide variety of research projects. Excellentfacilities in a modern building. Generous stipendplus tuition and fees for 12 months. Apply byApril 1, 1965 to Dr. Richard Abrams, Depart-ment of Biochemistry and Nutrition, GraduateSchool of Public Health, University of Pittsburgh,Pittsburgh, Pennsylvania 15213.

PHYSIOLOGIST-PHARMACOLOGIST - Ph.D.

Seeking a Ph.D., with broad training inpharmacological/physiological disciplineswith 0 to 5 years' experience. Researchopportunities include investigations in avariety of areas Including analgesics, anti-inflammatory agents, nasal decongestents,respiratory physiology and gastrointestinalphysiology/pharmacology. A knowledge ofthe principles of statistical evaluation ofbiological data is highly desirable.Please send resums including ,salary requirements to: Cyrus aM. Greenberg. Ph.D., Direeter_of Scientific Employment, 'SMITH KLINE & FRENCH LABORA-TORIES, 1570 Spring Garden Street,Philadelphia, Pa. 19101.

An Equal Opportunity Employer

1178

BIOCHEMISTChallenging position for Ph.D. biochemist,

pharmacologist, or physiologist on staff of young,rapidly growing Research Institute. Primary re-sponsibility would be to develop research pro-grams on the interaction of drugs with mam-malian systems. Position allows considerableflexibility in development of research directions.Send resume in confidence, with salary require-

ments and availability, to:Professional Personnel Manager

North Star Research and Development Institute3100-38th Avenue South

Minneapolis, Minnesota 55406An Equal Opportunity Employer

RESEARCH ORGANIC CHEMISTUnusual opportunity for an imaginative scientistwith experience in the application of analyticalinstrumentation to biochemical investigations.Offered by a rapidly growing, medically oriented,commercial organization in Florida. Salary com-mensurate with qualifications.

BOX 89, SCIENCE

RESEARCHVIROLOGIST

Recent graduate orwith experience.

**lrn*rBackground and in-terests in viral diseases and im-munology. General medical mi-crobiologist can qualify. Grad-uate students expecting degree innear future will be considered.Interested persons write to Mr.Stanley Sawczuk, Research Per-sonnel.

Merck & Company, Inc.West Point, Pa.

An Equal Opportunity Employer

Teaching and research asslstantships availableJune 1 and Sept. 1 at the Carver ResearchFoundation and Tuskegee Institute leading tograduate degrees in Agriculture, Biology,Chemistry, Nutrition, and Food Science andTechnology. Stipends starting at $2400 theyear. Apply: The Director, Carver ResearchFoundation of Tuskegee Institute, TuskegeeInstitute, Alabama 36088

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DIVIIUONSCIENCE, VOL. 147

POSITIONS OPEN ! POSITONS OPEN

BACTERIOLOGIST-Ph.D.Chemotherapy

New position available in R & D division,major eastem drug mfr, for Ph.D. levelbacteriologist, preferably with severalyears experience in chemotherapy, todirect & supervise group engaged in theevaluation of agents for treatment ofbacterial & mycotic infections, includingsynthetic compounds & substances of bio-logical origin. Compensation commensu-rate with training & experience.In eonfidence kindly submit vitae & salaryrequirements to Box 88, SCIENCE.

CHIEF, CLINICALMICROBIOLOGIST

Philadelphia General HospitalSALARY OPEN

Requires a doctorate in microbiology andfive years postdoctorate experience inmedical microbiology, including three yearsin a supervisory capacity.

CHIEF, CLINICALCHEMIST

Philadelphia General HospitalSALARY $13,156-$14,374

Requires a doctorate in biochemistry orphysiological chemistry and five years post-doctorate experience in clinical chemistryinvolving clinical chemical analysis, in-terpretation and research, including threeyears supervising such activities.

TOXICOLOGISTPhiladelphia's Medical Examiner's

OfficeSALARY $9,672-$1 1,526

Itequires a doctorate in the physical, med-ical or biological sciences including coursesor experience in toxicology or pharmacologyand three years recent experience in chem-ical analysis utilizing advanced techniques,performssance of analysis and interpretationof results. All applicants must be UnitedStates citizens. Excellent Fringe Benefits.Send detailed resumes to: Joseph Gold-iberger, Director of Recruiting, 500 Munici-pal Services Building, Phila., Pa. 19107.

BIOCHEMISTS- Ph.D.Expanding R&D activities have made several re-search opportunities available for Ph.D.'s broadlytrained in biochemistry with 0 to 5 years post-doctoral experience. Duties will involve aiding inthe planning, initiating and supervising of re-search investigations in the areas of neurobio-chemistry, enzymology or lipid metabolism. Addi-tional experience in physiology is desirable.

PHYSIOLOGIST-PHARMACOLOGIST-Ph.D.

Seeking a Ph.D. with broad training in pharma-cological/physiological disciplines with 0 to 5years' experience. Research opportunities includeinvestigations in a variety of areas including an-algesics, anti-inflammatory agents, nasal decon-gestents, respiratory physiology and gastrointes-tinal physiology/pharmacology. A knowledge ofthe principles of statistical evaluation of biolog-ical data is highly desirable.

Please send r6sum6 including salary etrequirements to: Cyrus M. Greenberg,Ph.D., Director of Scientific Employ-ment. SMITH KLINE & FRENCHLABORATORIES, 1570 Spring Garden Street,Philadelphia, Pa. 19101. An Equal OpportunityEmployer.

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7802-G. OVEN, Thomas-Weber, Model 25. For operationfrom 60° to 260°C. Chamber 14 inches wide X 10 inchesdeep X 12 inches high. Overall dimensions 16-s inches wideX 18- 1' inches deep X 26-' ) inches high. Two-heat switchselects 300-watt or 800-watt heater inputs. With 300°CThermometer in 1°divisions. For 113 volts, a.c..... 350.007802-H. Ditto, for 230 volts, a................. 350.00

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