APRIL 13, 1945SCIENCE-ADVERTISEMENTS 11~~~~-

* DYNAMWC METEOROLOGYBy J. HOLMBOE, Professor of Meteorology; W. GUSTIN, Instructor of Meteorology; G.FORSYTHE, former Instructor of Meteorology; all at the University of California

Starts from the fundamental principles of Physics and develops the tools of thermodynamics andhydrodynamics needed for the understanding of atmospheric processes. The methods of vectoralgebra and a few'simple operations of vector calculus are used as most naturally representing theconcepts of atmospheric motion. The book is self-contained and presupposes only a basic knowl-edge of general physics and calculus. Beady in April.

Approx. 375 pages; 5% by 8%; Probable price $4.50

* ANALYSIS OF FOODSBy ANDREW L. WINTON and KATE BARBER WINTON

Methods described in this book include not only those that have been tested and adopted in thiscountry and abroad, but many that have been only recently developed in recognized laboratories.They have been selected for the purpose of furthering the general knowledge of the compositionof foods. More than a thousand methods and modifications are included, and the presentation isconcise without omission of essential detail. Ready in April.

999 pages; 61A4 by 8'S/16; $12.00

* PLANE AND SPHERICAL TRIGONOMETRYBy H. A. SIMMONS, Professor of Mathematics, Northwestern University, and GREENVILLED. GORE, Professor of Mathematics, Central Y.M.C.A. College of Chicago

This greatly enlarged second edition begins with trigonometric functions of the general angle,instead of the positive acute angle, and includes precisely the solid geometry that is needed forspherical trigonometry. The book contains spherical trigonometry, with applications, and anunusually complete set of tables, as well as chapters on complex numbers and the slide rule. Beadyin May.

Approx. 511 pages; 5% by 8%; Probable price $2.75

* PRINCIPLES OF FIREARMSBy CHARLES E. BALLEISEN

A comprehensive study of firearms, showing how to design and analyze guns in accordance withthe laws of physics. Not a catalogue or historical record, this book gives a thorough discussionof small arms, from an explanatory, rather than descriptive, viewpoint. The newest methods oftesting firearms are given, including the use of electronic devices which now permit recordingof transient data. Earlier methods still in use are also described. Beady in April.

Approx. 161 pages; 6% by 81/2; Probable price $2.50

* SCIENTIFIC SOCIETIES IN THE UNITED STATESBy RALPH S. BATES, Massachusetts Institute of Technology

The only book that gives a complete survey of the evolution of American scientific societies duringthe past two and a half centuries, covering national, state and local organizations. Proceedings,transactions and other publications of hundreds of scientific societies were used in the preparationof this book. Beady in May.

Approx. 246 pages; 5% by 8%; Probable price $3.50

JOHN WILEY & SONS, Inc., 440-4th Ave., New York 16

1 ..l

APRIL 131 1945A

SCIENCE-ADVERTISEMENTS 11

h,.

SCIENCE-SUPPLEMENT

SCIENCE NEWSScience Semvice, Wahington, D. C.

ARTIFICIAL LIMBS FOR WAR VETERANSENGINEERING and surgical talent is going to work on

the job of developing the best possible artificial limbsfor war veterans. For the first time, engineers and

surgeons will tackle the problem together in a large-seale,organized effort.

All types of artificial limbs that have been developedin this country and in England, Russia, South Africa andelsewhere will be studied by a newly established com-

mittee of.the National Research Council. In addition to

searching for the best features now available, the com-

mittee may through its own research develop new, stillbetter, mechanisms.

The committee was created by the National Academyof Sciences and the National Research Council at therequest' of the Surgeon-General of the Army, followinga meeting of representatives of' the Navy, Veterans Ad-ministration and limb manufacturers, as well as of theArmy. The chairman of the committee is Dr. Paul E.Klopsteg, professor of applied science at NorthwesternUniversity and director of research of the NorthwesternTechnological Institute.The Army at present does a custom job of contouring

and fitting the artificial legs, arms, hands and feet that itsupplies to wounded soldiers. But it buys certain raw ma-

terials and prefabricated parts. Its new specifications callfor the best joints available, but it ishoping for spm-thing still better. It is pointed out that joints for arti-ficial limbs are not yet of as high a type 'as the joints

found in airplanes.Fit, weight, durability, maintenance and repair are

other problems to be considered by the new committee.The Veterans Administration would like to be sure, forexample, that if a veteran gets a leg in New York Cityand then moves to El Paso, Texas, he can get repairs forit there without difficulty.The Veterans Administration has contracts with about

150 artificial limb manufacturers. Where possible, thelimbs for veterans in its ninety-four hospitals are boughtfrom manufacturerswin the region of each hospital. This

simplifies the problei o6f repairs to some extent, but thereare always cases of veterans needing service while travel-ing if they have not moved from the region.Each manufacturer at present has patented the special

features of his product that are unique to it. For.theVeterans Administration, which mkes very few artificiallimbs, it would be desirable to have a reciprocal agreementworked out so that manufacturers might use each other'spatented features to develop satisfactory limbs forveterans.One of the aims of the new committee is to bring about

as much standardization as-possible in parts and mecha-nisms to assure simplification of maintenance and repair.Dr. Charles F- Kettering) head of the Qpneral MotoraResearch Division, D)troit, aid Dr. Roy 1). Medlure, chiefsurgeon of Henry Ford Hospital, Detroit, are consultantsX the committee.'

The operating headquarters of the committee are atNorthwestern University, Evanston, I11.-JANE STAFFORD.

ITEMSEvrrmicR of great economy in the animal body 's use of

mineral elements is offered in a study by Professor G.Hevesy, of the University of Copenhagen, on "tagged"atoms of artificially radioactive phosphorus in laboratorymice. The research is reported in a testimonial volumecelebrating the sixtieth birthday of the noted physicist,Professor The Svedberg, of the University of Uppsala, re-cently published in Sweden, copies of.which have just beenreceived in this country. Professor Hevesy injected intothe bodies of pregnant female mice a solution of aphosphate which had been rendered artificially radio-active, so that the atoms could be detected by suitableapparatus wherever they turned up. After the youngmice were born, one was immediately killed.and.its bodytissues analyzed to find how much of the maternal dowryof " tagged " phosphorus had been passed on to it. Afterthree months, when the new mice were full-grown, anotherwas killed and similarly analyzed. It was found that40 per cent. of the phosphorus concentration present inthe newborn mouse still remained in the body of its litter-mate three months later. In another series of experi-ments, the radioactively " tagged " phosphorus atoms.were traced through three generations. The concentra-tion mi the'granddaughter mice was found to be six:tenths of one per cent. of what it had been in their moth-ers at birth.

THAT the death rate from childhood diseases has been.reduced no less than 93 per cent. during the past twentyyears, is reported by the Metropolitan Life InsuranceCompany. There are 90 per cent. fewer deaths fromscarlet fever and 80 per cent. fewer deaths from bothwhooping cough und, measles.' The death rgte from''a diph-theria among children of elementary school age,'. whowere insured by the company, is only 1/26 what it wastwo decades ago. Only one fourth as many die to-dayfrom tuberculosis and pneumonia as would if the mor-tality rate of twenty years ago still prevailed. Thedeath rate among children between the ages of five andfourteen from all causes combined was cut 65 per cent.between 1922-23 and 1942-43. For every two childrenwho die wider current conditions, more .thpn fiy ould'have died if the death rate of two decades ago Sk con-tinued, the company estimates. All colors and both sexeshave benefited by this improvement, but some more thanothers. The reduction in deaths among children. of thisage group, as shown among those insured in the com-pany 's -industrial department, is larger among whitechildren than among colored. Girls have profited morethan boys. Children of elementary school age are onlyhalf as likely to have fatal accidents to-day as they were

twenty years ago. Children are only about one quarteras likely to-day to die from burns .an-d'.scalds.

VOL. 101 No. 262412

APRIL 13, 1945 SCIENCE-ADVERTISEMENTS

Recent Crowell Books

1. GLOBAL GEOGRAPHYBy-Gleorge T. Renner, Professor of Geography, Teachers College, Columbia University, and twenty-nine Associates. 728 pages, 165 illustrations. $3.75.

A new kind of book that emphasizes the dynamic approach to geography. Five printings and more thaneighty adoptions within nine months of publication.

2. ASTRONOMICAL AIR NAVIGATIONBy Ronald Hdgham,,Squadron Leader, Royal Air Force. 132 pages, 58 figures, 1S tables. $2.50

A comprehensive handbook explaining the most up-to-date methods of navigation by reference to theHeavenly- Bodies. It fills the need of all who would get to the heart of practical celestial navigationwithout frills and theory.

3. INTRODUCTION TO QUANTITATIVE ANALYSISBy Saul B. Arenson, Professor of Chemistry, University of Cincinnati, andGeorge B. Rteveschl, Jr., Parke, Davin and Company, Detroit. 386 pages, 51 illustrations. $2.75

A compact, informal and thoroughly modern text featuring 1) theoretical treatment of colorimetry,turbidimetry, adsorption indicators and electrochemical applications, 2) use of titrimetry and organicreagents, 3) early introduction of experiments for rapid completion, 4) large number and variety ofexperiments and problems..

4. Laboratory Notebook for INTRODUCTION TO QUANTITATIVEANALYSIS .; 0By Arenson and Rieveschl. 92 pages. $.75

Deniknea to acewpany the aithors' text as a guide inm recording data.

5. HOW TO SOLVE PROBLEMS IN PHYSICAL CHEMISTRYBy Joseph A. Babor, Associate Professor of Chemistry, College of the City of New York, andGarrett W. Thieen, -Associate Professor of Chemistry, Monmouth CoIjege. 215 pages. $1.25

Prepared especially to enable students 1) to vinualize a given problem, 2) to seleet- the proper- method forsolving it, and 3) to carry it through to a satisfactory solution.

-6. THE SCIENCE OF EXPLOSIVESBy Martin Meyer, Chairman, Department of Chemistry, Brooklyn College. 452 pages, 74 illus-trations. $4.50

Presents m reasonably simple and readable style a comprehensive treatment of the chemistry, productionand analysis of the fundamental types of explosives. The theory of explosive action is discussed andpractical initiating devices are deseyibqd.

Thore hS beet oplcein X any text or maual since before Pearl Harbor.

Thomas Y. trowell CompanyPlease send me the books 'whose numbers I have checked

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14 SCIENCE-ADVERTISEMENTS VOL. 101, No. 2624

.~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~PrincetonBooks

on theScience of

Mathematics-

The Psychology ofInvention-inin the

Mathematical FieldBy JACQUES -HADAMARD

An engaging, informal analysis of the workings of a mathemati-cian's mind, based partly on the author's introspection and partlyon the writings and statements of many other noted mathemati-cians.

Among the phenomena discussed: Conscious and unconsciousthinking, the use of mental images and symbols, "logic," "tin-tuition." $2.00

How to Solve ItA New Aspect of Mathematical Method

By GEORGE POLYA

A disarmingly elementary book which tells in general terms, andand with a wealth of illustrations, `what everybody knows butnobody cares to express; the procedures of the mind in searchingfor solutions of problems." The examples are simple, but themethod is applicable to a whole range of problems in many scien-tific fields. May. $2.50

At your bookstorePRINCETONUNIVERSITY

PRESS,Princeton, N. r.

The Meaning ofRelativityBy ALBERT EINSTEIN

A reissue of the classic presentation of the theory of relativity,with an appendix discussing advances in the theory since 1921.

$2.00

SCIENCE-ADVERTISEMENTS.14 VOL. 101, No. 2624

APRIL 13,1945 SCIENQE-ADVERTISEMENTS 15~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

4BS BORPTION CELLSThe Recognized Standard

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* Fully Described in Bulletin A-2130 *

_~uI~ii~uU~ti~iL'iI~m---A

INFANT AND CHILDE.IN THECULTURE OF TODAYThe Guidance of Development in

Home and Nursery School

By ARNOLD GESELL, M.D.and FRANCES L. ILG, M.D.

14th Printing Illustrated $4.00

THE FIRST FIVE YEARS OF LIFEA Guide to the Study of the

Preschool ChildBy ARNOLD GESELL, M.D.

andHENRY M. HALVERSON, PH.D.,

FRANCES L. ILG, M.D.,CATHERINE S. AMATRUDA, M.D.,

HELEN THOMPSON, PH.D.,BURTON M. CASTNER, PH.D.,LOUISE BATES AMES, PH.D.

10th Printing Illustrated $4.00aI o.td tcte I

A Revolutionary Contributionto the Story of ManTHE EMBRYOLOGYOF BEHAVIOR

The Beginnings of the Human MindBy ARNOLD GESELL, M.D.

in collaboration withCATHERINE S. AMATRUDA, M.D.

A completely detailed survey of the transformationof behavior between the fetal age of 28 weeks andlater infancy, which includes a large section of ex-traordinary photographs called a Photographic De-lineation of the Beginnings of Human Behavior.

$5.00

DEVELOPMENTAL DIAGNOSISNormal and Abnormal Child

DevelopmentBy ARNOLD GESELL, M.D.

and CATHERINE S. AMATRUDA, M.D.Published by PAUL B. HOEBER, INC.,Medical Book Dept. of Harper & Brothers.

$6.50At all bookstores or direct fromHARPER & BROTHERS

49 East 33rd Street, New York 16

APRIL 13, 1945 SCIENCE-ADVERTISEMENTS 15

16 SCIENCE-ADVERTISEMENTS VOL. 101,

In a wind tunnel an AERONAUTICALENGINEER uses a 40,000 horsepowerelectric motor to create a 400-mile-an-hour tornado for testing war planes.

... the name on the MOTOR is Westinghouse.

In a factory a WORKER assemblesdelicate bomb-sight part's in air' made dust-free Ey the Precipitron electrostaticair cleaner.

... the name on the PRECIPITRON* is Westinghouse.

In a penicillin plant a SCIENTIST usesa Sterilamp bactericidal tube to protectthis life-saving drug from contaminationby air-borne bacteria.

... the name on the STERILAMP* is' Westinghouse.

. On America's largest aircraft carriers theNAVY uses steam turbines which makeour carriers the world's fastest.

..the name on the TURBINES is Westinghouse.

TODAY - These are some of the ways in which Westinghouseproducts are serving in the war effort.

X4festinSse TOMORROW- Existing and new products of WestinghousePLANTS IN 25 CiTIES OFFICES EVERYWHERE research and engineering will serve industry and the home.

-TRADEMARK REC. U.S. PAT. OFF.Tune in: JOHN CHARLES THOMAS

Sunday 2:30 pm, EWT, NBC. TED MALONE-Mon. Tues. Wed. Evening; Blue Network

SCIENCE-ADVERTISEMENTS VOL. 101, No. 262416

=_~~~~wIN T lE M A R K E T P L A C E

Rates, 10¢ a word, minimum $2.00 cash in advance. Count 8 words if a box address is to be used. Display inser-tions, $8.80 per Inch. Copy should be sent to the Advertising Department, American AsscIation for the Advance-ment of Seience Smithsonian Institution Building, Washington 25, D. C.

POSITIONS OPEN

Two Technicians. Permanent Laboratory Posi-tions. Needed by a leading Biological SupplyHouse.

(a) Head of Preserved Materials Department inbranch laboratory being built in deep South. Willbe responsible for preserving, injecting, embalminganimal specimens used in dissection. Young manpreferred. Prior experience helpful.

(b) Head of Slide Department in home or branchlaboratory. Must be capable of making and super-vising the preparation of quality microscope slides.State education, experience, age, salary desired andwhen available for duty. Box 137, " ScIENCE,7"Smithsonian Institution Building, Washington 25,D. C.Opportunities Available. (a) Bacteriologist orpharmacologist trained in business to join staff oflarge pharmaceutical company; duties consist oftraveling throughout country instructing and train-ing groups of employees; $4,000-$5,000 includingexpenses. (b) Associate professor of bacteriology;relatively young man, preferably physician; Ph.D.eligible; teaching experience and ability in researchrequired; university medical center; South. (c)Director of clinical laboratories, largo industrialcompany; approximately 7,500 tests per month;staff of twenty; young man with Ph.D. in bacteriol-ogy or chemistry required. (d) Professor of Phar-macology for appointment with university operatedunder American auspices in Asia; country pre-.dominantly Christian; city in which university islocated has population of 150,000 and is consideredimportant seaport. (e) Chemical technician;senior position, with 14-man clinic, most of whomhave held academic appointments before joiningorganization; hospital splendidly endowed; ampleresearch opportunities; residential town, East.S4-1 Medical Bureau (BBURNEICE LARSON, Director),Palmolive Building, Chicago 11.

POSITION S WANTEDPhysiologist, Ph.D. Zoology, age 42. Now hold-ing responsible teaching and administrative posi-tion in Zoology department of large eastern Uni-versity. Wishes teaching position in Universityor Medical College with opportunities for research.Research neuro-physiology. Available September.Box 136, "SCIENCE," Smithsonian InstitutionBuilding, Washington 25, D. C.

Opportunity Wanted. Chemist is available; B.Sc.(pharmacy), M.Sc. (physiological chemistry),Ph.D. (major pharmacy, pharmacognosy; minorchemistry, bacteriology), leading universities; sev-eral years' successful teaching experience includingthree years as assistant professor of pharmacysouthern university; past several years, directorresearch and supervisor of production pharmaceuti-cal company; for further details please writeBURNEICE LARSON, Director, Medical Bureau, Palm-olive Building, Chicago 11.

SUPPLIES

Itaconic Acid available in small quantities. Price9 cents per gram. BEN VENuIE LABORATORIES, INC.,270 Northfield Rd., Bedford, Ohio.

andDihydroxyacetone available at 75 cents per gramin lots over 500 grams. BEN VENUE LARORATORIES,INC., 270 Northfield Rd., Bedford, Ohio.

Electronic-Hardened Filter PaperNo. 576; MIcro Inut-Free;for Biological Products

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desiredBECKER BALANCES, INC.H. C. Becker, Director481 lin St. New RocdeD., N. Y.

BOOKB AND PERIODICAL

Wanted to purchase Scientific Periodicals, For-eign-Domestic. WALqTER J. JOHNSON, 125East 23rd Street, New York 10, New York.

For Sale: Medical, Chemical, and Scientific Peri-odicals. Sets, volumes, copies. B. tLOGIN ANDSON, INC. Established 1887, 29 East 21st St.,New York 10.

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BAECE-ADD-ESISEMENTS VoI. 101, No. 2624:

.1. - 7.1' 1

at &-. m j

Physicians, sutgeons and others en-

gaged in medical research have, in

recent years, employed vanrius Fiber-glas materials experimentally andhave found them ui vy itted forcertain ues.

For example, Fiberglas cloth (ECC:11-108)-. ws- used to help measure

the protein loss in the exudate-from-surface~burns. As i-lu.trWd, theFibrglas cloth was placed next to

the burned skin of a 12-year-old

Negro girl. it is .the first layer of abandage devid to collect *e exu-

date In order accurately to measure

nitrogen' 'loss- from the 'Iridt'skinsurface. The patiesit wasadmitted tod:a Detroit hospital in J-anur,The burn, caused by -hot water, in-volved about 12 per cent of the bodysurface. "The burn healed rapidly,"

says the report in Surgery, "and the

amount of nitrogen lost in- the exu-

date from the burned area diminished-a healing progressed."

This methodof determining themag-nitude of the protein loss from theburned siirface gives physicians a com-pehensive picture of the etabolicupset for the first time and thus will: tmit imj~ved replacement th rpy

Fibeg is glass in fiber or fila-net frr. Glass textile fib*s, rang-ing in diameter from; four -ten-thou-sandths of an inch to less than twoten-thousandths of an inch are formedinto yarns which are woven into a.

*-wid&e variety of textiles.Fiberglas is an inorganic, nontoxic,

nonallergenic,. nonsensitizihg andchemically stable- substance whichproduces no harmful effect upon hu-man tissue.It is pliable and possesses

great tensile strength. It has highdimensional stability, resists hightemperatures, steam, corrosive fumesand acids (except hydrofluoric).

- laiherglas is nonhygroacopic and non-

inflammable. It is easily sterilizedand resteiilized, and in a special form

pP.is radiopaque

1 BEROGUL:AS'*T.M.Rtg.U.S.Pat.Off.

it is the poiicy of OwOe-Comnbg FiberglasCorporation to supply smples of Fiberglasi any availabW1orm to qulified personsengaged In research The now brohuredebig s other poperng uses ofFiberglas Os.

. Trocer hreads in Surgical Sponges

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APRIL .13, 1945 SCIENCE-ADVERTISEMENTS 19

Bacto-Agar

Bacto-Agar is a purified Agar prepared fromdomestic material. In the manufacture ofBacto-Agar extraneous matter, pigmented portions,and salts are reduced to a minimum, so that thefinished product in the form of fine granules willdissolve rapidly, giving clear solutions.

Bacto-Agar is distributed only for use in

bacteriological culture media upon propercertification by the purchaser.

Bacto-AsparagineBacto-Asparagine is a purified amino acid

widely used in synthetic culture media and in thepreparation of tuberculin.

Specify "DIFCO"THE TRADE NAME OF THE PIONEERS

In the Research and Development of Bacto-Peptone andDehydrated Culture Media.

DIFCO LABORATORIESI N C O R PO R A T E D

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A complete line for clinical laboratories de.voted to all branches of chemistry, bacteri.ology, hematology, and parasitology. Testedand checked in our own clinical laboratqerisPurity warranted. Our facilities assure promptshipment of large or small orders. Inquiriesinvited.

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All types of Microscopes, Magnifiers, and other scien-tific instruments In stock for prompt delivery.

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Reagents catalogued alphabet.ically-also according to sub.jects and techniques, plus med.ical reference guide.,- Catalog

ANNOUNCINGA NEW SERIES OF

LaMOTTE WATER SOLUBLEpH INDICATORS

(Sulfon-phthalens) pH 0.2-9.6

In Sparkling Crystalline Form

New, highly purified.products, forming instant so-lution with distilled water. No alkali to be added-no mixing in mortar-no filtering-no waiting.Simply add the proper quantity of the new La-Motte Indicator to distilled water in dilution flaskand a brilliant solution of maximum sensitivity,stability, and tinctorial powder results.In new containers of 1 gram ea.

Made exclusively by.

LaMotte Chemical Products Co.Dept. H

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c--om-p--ri-s~e~s~-f-u-l~l Ti-.e- bfood test-ing sera including anti-Rh,anti-M and anti.N; also re.

gent& for Wassermann, Kline,:nd Kahn tests. Write for yourcopy. FREE ON REQUEST.

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APRIL /13. 1945 SCIENCE-ADVERTISEMENTS 19

NOWREADY

THE OPTICAL TOOLS OF SCIENCE . . . HAND MAGNIFIERS

An essential part of the laboratory equipment, Bausch &Lomb Hand Magnifiers are built to exacting optical stan-dards. There is a Bausch & Lomb magnifier to fit everytype of visual examination. Typical magnifiers shown arethe B&L Watchmakers' Loupe, Round Reading Glass, Pock-et Magnarule and Folding Pocket Magnifier. RequestCatalog I-15, Magnifiers & Readers. Bausch & Lomb Opti.cal Co., Rochester 2, N. Y.

BAUSCH & LOMBESTABLISHED 18 5 3

SCIENCE-ADVERTISEMENTS VOL. 101, No. 262420

SCIENCE-ADVERTISEMENTS 21

More than Iron and SteelIron - steel - brQnze - copper - aluminum - magnesium - allare used in the manufacture of International Centrifuges. Butmore important than any of these is the skill and reputation of themaker, acquired through more than forty years of experience inCentrifuge production. These are your guarantee that eachInternational Centrifuge is a product of finest quality.

Cflafers of dine gentrifuges for (Cllore t1an cgorky 9JearsINTERNATIONAL EQUIPMENT COMPANY

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APRLIL 13,- 1945

SCIENCE-ADVERTISEMENTS

- Speed: Saves a Life

A'commander and pharmacist's mateare preparing to- cut thin sections oftissue taken from a member of the Navypersonnel. Speed is essential, for. theman is on the operating table and a

diagnosis of the pathology is,necessary.A Spencer Clinical Microtonie is used

to- frez e tissue and `tut sections. It

takes only.amnute or two to get a

section for microscopic examination.The photograph above was made at

the U. S. Naval Hospital at St. -Albans,*Long Island, where Navy, Coast Guard

and Marine Corps men, many of whomare flown from battlefronts by air trans-port, are given the benefit of the mostadvanced medical skill.

Spencer LENS COMPANYBUFFALO, NEW YORK

SCIENTIFIC INSTRUMENT DIVISION OFAMERICAN OPTICAL COMPANY

. 1 k -._~1

VOL. loli No. 2624