12
SCIENCE-ADVERTISEMENTS 11 BAUSCH & LOMB BALO PT ICON MODEL B This Balopticon, for use with standard lantern slides, is in produc- tion for your use. It is moderately priced and provides an economical means of illustrating lectures and group discussions. Its optical and illuminating systems are of exceptionally high quality and permit large, brilliant, clear screen pictures critically sharp from one edge of the screen to the other. Because of its sturdy construction and ease of operation it is particularly well adapted for use by inexperienced operators and will provide long, trouble-free service. Write for complete information. Ask for Catalog E-11. Bausch & Lomb Optical Co., Rochester 2, N. Y. BAUSCH & LOMB E ST A BLI S HED 1 85 3 V_ DECEMBER 14p 1945

DECEMBER BAUSCH LOMB - Science | AAAS · BAUSCH & LOMB BALOPTICON MODEL B This ... and brought under one general principle and solution-statistical procedures associated 261by 8*

  • Upload
    vudung

  • View
    216

  • Download
    0

Embed Size (px)

Citation preview

Page 1: DECEMBER BAUSCH LOMB - Science | AAAS · BAUSCH & LOMB BALOPTICON MODEL B This ... and brought under one general principle and solution-statistical procedures associated 261by 8*

SCIENCE-ADVERTISEMENTS 11

BAUSCH & LOMB

BALO PT ICON MODEL B

This Balopticon, for use with standard lantern slides, is in produc-tion for your use. It is moderately priced and provides an economicalmeans of illustrating lectures and group discussions. Its optical andilluminating systems are of exceptionally high quality and permitlarge, brilliant, clear screen pictures critically sharp from one edgeof the screen to the other. Because of its sturdy construction and easeof operation it is particularly well adapted for use by inexperiencedoperators and will provide long, trouble-free service. Write forcomplete information. Ask for Catalog E-11. Bausch & LombOptical Co., Rochester 2, N. Y.

BAUSCH & LOMBESTABLI SHED 1 85 3V_

DECEMBER 14p 1945

Page 2: DECEMBER BAUSCH LOMB - Science | AAAS · BAUSCH & LOMB BALOPTICON MODEL B This ... and brought under one general principle and solution-statistical procedures associated 261by 8*

12 SCIENCE-ADVERTISEMENTS VoL. 102, No. 265~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

WILEY Books on 0

or Interest to SAC Kt> STATISTICAL ADJUSTMENT OF DATA

By W. EDWARDS DEMING, Head Mathematician, Bureau of the Census

A practical textbook in statistical adjustment. Different kinds of problems are unified 261 paesand brought under one general principle and solution-statistical procedures associated 261 by 8*with curve fitting and other adjustments by least squares and skeleton table forms for $3.50numerical calculations. Suitable for courses in graduate chemistry, physics, sociology,agriculture or biology. 1948.

* TREATMENT OF EXPERIMENTAL DATABy ARCHIE G. WORTHING, Professor of Physics, University of Pittsburgh,and JOSEPH GEFFNER, Weirton Steel Co.

Prepared primarily for physicists, chemists and engineers. The book tells how to set up 342 pagestables, including instruction on the use of legends; how to prepare graphs giving sufficient 6 by 9*descriptive information so they may be read easily; how to set up equations; how to $4.50determine, express and apply precision indexes, and similar matters. 1943.

METHODS OF CORRELATION ANALYSISBy MORDECAI EZEKIEL, Economic Adviser to the Secretary of Agriculture

For use in advanced courses in statistical analysis and correlation methods, and in theuses of statistical methods in studying multiple causation and multiple relationships.Emphasis is given to modern developments in the theories of sampling and the shortcutmethod of correlation. This second edition has been enlarged and revised, and wherevernecessary charts and graphs have been revised. 1941.

* STATISTICAL METHODS in Biology, Medicine and PsychologyBy C. B. DAVENPORT, Carnegie institution of Washington, Cold Spring Harbor,N. E., and MERLE P. EKAS

A compact, working manual, showing methods of computing statistics, as well as illustra-tions of some of the machines that make these computations. Includes treatments ofsuch methods as Dr. R. A. Fisher's analysis of variance and extension of the theory ofsmall samples; and the expansion of the theory of correlation to the inclusion of multipleand partial correlations. For use as a practical reference and guide in laboratory workon variations in the fields of biology, agriculture, medicine, psychology, education, com-merce, physics and chemistry. 1936.

* AN INTRODUCTION TO PHYSICAL STATISTICSBy ROBERT BRUCE LINDSAY, Hazard Professor of Physics, Brown University

This book presents a brief survey of, and introduction to, all the fundamental methods ofstatistical technique now in use in physics, with a careful analysis of how they are used.Based on a course which the author has offered his students, it is suitable for use in ad-vanced courses in physical statistics and statistical mechanics. A knowledge of theoreticalphysics and advanced calculus is a prerequisite. 1941.

Second edition531 pages6 by 9*$5.00

vFourth edition

216 pages41 by 7A

$2.75

v306 pages6 by 9i$3.75

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

w-

miam

12 SCIENCE-ADVERTISEMENTS VOL. 102. No. 2659

Page 3: DECEMBER BAUSCH LOMB - Science | AAAS · BAUSCH & LOMB BALOPTICON MODEL B This ... and brought under one general principle and solution-statistical procedures associated 261by 8*

DEEBR1,14 CEC-DETSMNS1

EXPERIMENTAL BIOLOGY MONOGRAPHS

This important series of scientific monographs constitutes a cumu-lative library on research in the various branches of the biologicalsciences in which substantial progress is being made. Each ofthe volumes listed below is written by an active worker, or work-ers, in its field; and presents a summary of the experimental con-tributions to that field and discusses in detail the theoretical im-plications of important experimental findings.

PHYTOHORMONESBy F. W. WENT, Calif. Inst. of Tech-nology and K. V. TUMMANN, HarvardUniversity294 pages Illustrated $4.00

THE EGGS OFMAMMALS

By G. PINcus, Harvard University160 pages Illustrated $3.75

VERTEBRATEPHOTORECEPTORS

By S. R. DETWILER, College of Physi-cians and Surgeons, Columbia Univer-sity184 pages Illustrated $4.00

AUTONOMIC NEURO-EFFECTOR SYSTEMS

By W. B. CANNON and A. ROSEN-BLUETH, both of Harvard University229 pages Illustrated $4.00

NEUROEMBRYOLOGYAN EXPERIMENTAL STUDY

By S. R. DETWILER

218 pages Illustrated $3.75

PACEMAKERS INRELATION TO ASPECTS

OF BEHAVIOR

By H. HOAGLAND, Clark University138 pages Illustrated $3.00

DYNAMICS OFINFLAMMATION

AN INQUIRY INTO THEMECHANISM OF INFECTIOUS

PROCESSES

By VALY MENKIN, Harvard Univer-sity Medical School

244 pages Illustrated $4.50

DicczmBzR 14, 1945 SCIENCE-ADVERTISEMENTS 13

Page 4: DECEMBER BAUSCH LOMB - Science | AAAS · BAUSCH & LOMB BALOPTICON MODEL B This ... and brought under one general principle and solution-statistical procedures associated 261by 8*

SCIENCE-ADVERTISEMENTS VoL. 102, No. 2659

l4a a# ct7 4 m 9 t-W

Handbook of MeteorologyEdited by F. A. BERRY, JF., Captain, USN; E. BoL-LAY, Lieut. Comdr., USNR; and NoRMAN R. BEERS,Lieut., USNR. Assisted by a Staff of Specialists.1068 pages, 51 x 81, 730 illustrations. $7.50

An invaluable text and reference book covering the en-

tire subject of meteorology, and presenting a wealth ofauthoritative information on mathematics; physics of theair; radiation; descriptive meteorology; climatology; dy-namic meteorology; instruments; codes, maps, and plot-ting; synoptic meteorology and weather forecasting;oceanography; and hydrometeorology.

Wave Propagation in PeriodicStructures. Electric Filters andCrystal Lattices

By LEON BRILLOUIN, Columbia University. 247 pages,

5j x 81, 137 illustrations. $3.50

This volume incorporates a variety of problems linked bya common mathematical background, extending from elec-trical engineering to electromagnetism and wave me-

chanics of the spinning electron. All problems deal withperiodic structures of various kinds, which invariably,whether they are electric lines or crystal lattices, behavelike band-pass filters.

General ChemistryBy JOHN ARREND TIMm, Simmons College. Interna-tional Chemical Series. 691 pages, 51 x 81, 185 illus-trations. $3.75

Off to an excellent start, this distinctive text has won theapproval of teachers and reviewers, who praise the clear,graphic presentation and the vivid, readable style. Thetext is planned for students who expect to use chemistryin their professional education, and is suitable for be-ginners as well as those who have completed an elementarycourse in secondary school. One of the features of thebook is the sound modern approach to the fundamentaltheory.

General Zoology0

By TRACY I. STORER, University of California at Davis.McGraw-Hill Publications in the Zoological Sciences.798 pages, 51 x 81, 551 illustrations. $3.75

This highly successful standard text, generally regardedas one of the best now available, represents an introduc-tion to zoology designed for a " types " course. Thebook provides a general biological approach and a sys-tematic review, in order to give the student a rationalunderstanding of the structure, function, and life char-acteristics of animals, as well as an orderly knowledge ofanimal types.

Laboratory Manual for GeneralZoology

By TRACY I. STORER. McGraw-Hill Publications inthe Zoological Sciences. 150 pages, 51 x 81, 20 illus-trations. $1.50

(A booklet, Suggestions for Laboratory Instructors, willbe furnished gratis to users of the Manual.)

The Chemical Process IndustriesBy R. NORRIS SHREVE, Purdue University. ChemicalEngineering Series. 941 pages, 51 x 81, 245 illustra-tions. Textbook edition, $6.00

Present-day teaching trends in chemical engineering arereflected in this successful and highly praised new book.Offering a definitely fresh approach, the author followsmodern factory practice in breaking down the actual in-dustrial procedures into unit operations and unit proc-esses, not only in the flow sheets, but in the supplementarytext as well.

Guide to the Southern TreesBy E. 8. HARRAR, Duke University, and J. G. HARaaR.Ready in February

The authors describe accurately yet simply the more than350 arborescent species native to the southern states.After a section on tree nomenclature and classification,the book reviews the important features of leaves, flowers,fruit, twigs, and bark which are commonly used in treeidentification. This is followed by sections on coniferoustrees and broadleaved species.

Send for copies on approval

14

McGRAW-HILL BOOK COMPANY, INC.330 West 42nd Street, New York 18, N. Y. Aldwych House, London, W.C.2.

Page 5: DECEMBER BAUSCH LOMB - Science | AAAS · BAUSCH & LOMB BALOPTICON MODEL B This ... and brought under one general principle and solution-statistical procedures associated 261by 8*

SCIENCE-ADVERTISEMENTS

eda4o (ezC 4 4 e

ARNOW'S 2nd EDITION

an d

by EARLE L. ARNOW,Ph.G., B.S., Ph.D., M.B., M.D.Director of Biochemical Research,

Medical-Research Division,Sharp & Dohme, Inc., Glenolden, Penna.

574 pages, 142 illustrations. $3.75

"Those who are not familiar with thistextbook will find it one of the mosteffectively written volumes of its type.. . .Not only is the prevailing thoughton biochemistry and physiology con-cisely presented, but the author's styleis engaging." Journal of the A.M.A.

"Students of nursing should find thisan invaluable text. This volume shouldalso be of great value as a referencefor physicians, physical therapists andthose who need to refresh themselvesin this vital subject."

Archives of Physical Medicine

"This new edition is a very worth-while contribution and its manner ofpresentation should make for improvedstudent interest in this oftentimes diffi-cult subject."

U. S. Naval Medical Bulletin

THE C. V. MOSBY COMPANY.3207 Washington Blvd.St. Louis 3, Mo.

Gentlemen: Send me a copy of Arnow'sand PATHOLOGICAL CHEMISTRY, $1

FI Attached is my check.

Fundamentally the new second editionof this popular book remains the same.However, Dr. Arnow has revised itthoroughly and has brought it up todate in accord with advances in thefield of biochemistry.For example, brief discussions of thesulfonamides, the importance of in-testinal bacterial synthesis of vitamins,and the newer members of the vitaminB complex have been included. In-creasing evidence that the renin mecha-nism may be important in pathogenesisof human hypertension has resulted inthe inclusion of this subject in thechapter on hormones. Newer con-cepts of muscle carbohydrate metabo-lism, hemoglobin catabolism and trans-methylation have been given.

To increase the book's usefulness notonly as a text but a reference, shortdescriptions of the van den Bergh test,the icterus index, the blood amylasetest and carbon dioxide combiningpower have- been included. Everyeffort has been made to make thisedition conform to prevailing viewsof the majority of biochemists andphysiologists.

Sdl. 12/45

INTRODUCTION TO PHYSIOLOGICAL3.75.

LI Charge my account.

Name..........

A ddress . . ...................................... ..............................

1

DicCEMBER 14) 1945 15

Page 6: DECEMBER BAUSCH LOMB - Science | AAAS · BAUSCH & LOMB BALOPTICON MODEL B This ... and brought under one general principle and solution-statistical procedures associated 261by 8*

16 SCIENCE-ADVERTISEMENTS VOL. 102, No. 2659

TWO BOOKS ON

Engineering.NOTES ON HelicopterDesign Theory

By ALEXANDER A. NIKOLSKY

A pioneering attempt by an aeronautical en-gineer who has had extensive experience withhelicopter development, at coordinating andevaluating existing analyses of helicopter designproblems. Professor Nikolsky served as as-sistant chief of design at the Sikorsky divisionof United Aircraft Corporation before joiningthe faculty of the Department of AeronauticalEngineering at Princeton.He presents these notes modestly and without

claiming that they are definitive. They repre-sent the text of lectures given at Princeton inthe spring of 1944, and are largely mathemati-cal in nature.

230 pages, planographed, paper cover, $3.00

THE Mechanics OFTurbulent Flow

By BORIS A. BAKHMETEFF

"A summary of turbulent fluid mechanics asapplied to flow in pipes which can be easilymastered by engineers and turned to practicalaccount. "-Engineering. "A series of lecturesdelivered under the William Pierson Field Foun-dation at Princeton in February 1935 (Revisedin 1941). Professor Bakhmeteff presents herethe recent findings of the Prandtl and Karmanschools in a systematic and simple form. Onlythe most elementary mathematical means areused, the aim always being to emphasize thephysical substance of the phenomena.' '-CivilEngineering.

116 pages, 62 figures, $2.50

Order from your localbookseller or from

PRINCETON UNIVERSITY PRESSPrinceton, N. 7. 4

K IMAC VIEWE Rb for . . .

2z 2" Kodachromes,35 mm. strip films, micro film,8 and 16 mm. Movie Films,Microscope Slides,Dental X-rays, stamps.

-~~~~~~~~~~~~~~~~~~~Made of attractive black plastic with re-movable black wood handle. Accommo-dates either a 4x or lOx (A-1672) lenswhich can be focused. The lOx lensgives higher magnification for 8 and 16mm. movie film, postage stamps, andmicroscope slides, or the central area of2 x 2" slides and 35 mm. film strips.Built-in slot for viewing 35 mm. stripfilm. Accessory attachment (A-1674A)fits into the 35 mm. slot for viewingeither 8 or 16 mm. movie film.

A-1671 Kimac Viewer with 4x eyepiece ........ Each $3.00A-1672 lox Eyepiece for Kimac Viewer ......... " 8.00A-1674A 8 or 16 mm. Movie Film Adapter ...... " 1.00A-1674 X-Ray Film and Postage Stamp Adapter " 1.00

CLAY-ADAMS CO ;DAMYJ~23rd~STBEET1.iI~w~ioiu~,~

AEROBIOLOGYviii + 299 quarto pages

(7 x101 inches)illustrated, references

This volume, one of the Symposia Series,consists of 37 papers. Eight papers coverextramural aerobiology which is concernedwith the distribution of living organismsby the exterior air and with some ofthe consequences of their distribution.Twenty-nine papers on intramural aero-biology cover (1) the problem of contagionby air-borne infectious materials, (2) ex-pulsion of secretions from the mouth andnose, and (3) infections from dissemina-tion of pathogenic organisms into the op-erating room, the hospital ward, the schooland the home. Published in 1942. $4.00.

American Association for theAdvancement of Science

Smithsonian Institution BuildingWashington 25, D. C.

16 SCIENCE-ADVERTISEMENTS VoL. 102, No. 2659

Page 7: DECEMBER BAUSCH LOMB - Science | AAAS · BAUSCH & LOMB BALOPTICON MODEL B This ... and brought under one general principle and solution-statistical procedures associated 261by 8*

DECoEMBER 14, 1945 SCIENCE-ADVERTISEMENTS

The Classic Treatise on

METEORITESTheir Structure, Composition and

Terrestrial Relations

By OLiVER CUMMINGS FARRINGTON, PH.D.Late Curator of Geology,

Chicago Natural History Museum

233 pp., 66 figs., Chicago, 1915Published by the Author

Price: $2.00 plus 10b for mailing.

Send orders with remittance to:

Society for Research on Meteorites

GRIFFITH OBSERVATORYP. 0. Box 9866

Los Feliz Station Los Angeles 27, Calif. HERE S WHY Cc s t 1e

__________________ PRECISION INCUBATORS* .... .. Give rigid temperature control

LAMOTTE BENEIDINE| It is the Triple Wall of the ,USEVOLUMETRIsC DETERMINATION Castle Precision Incubator that e COMFO5UION

OF SULFATES. -urne eatns nicb-CouO~Packaged In 25, 100 and 500 gram containers, urneseatesi nuaLaMOTTE N l-naphthyl) ethylenediamine dihydro- tion. A water jacket enclosed | 4l A*

-11 |chloride Marshall and Bratton's reagent for the by dead air sace surrounds the _-determination of Sulfonamides and Nitrites. chamber on all sides. Carefully =Packaged in 1, 5 and 10 gram containers. regulated heat applied to the 24 O0CO~

LAMOTTE QUINHYDRONE water in the jacket heats the - WM

USE-A highly purified reagent for use in the elec- by radiation, whichtrometric determination of H-ion concentration. means uniform penetration WAlEPackaged In 25; 100 and 500 gram containers. throughout.

LaMotte Chemical Products Company These triple-wall, water-jacketed incubators are preferredDept. "HI Towson 4, Baltimore, Md. for these features:

%0 C. Uniformity: Never as much as a degree variationbetween top and bottom of chamber when loaded.

l% to %10 C. Constancy: Never more than a fraction ofa degree variation at the thermometer-even though

R I C O B O T K A l l room temperature may fluctuate between 10 and

E I SO O K 5dity: Fresh air circulates through chamber con-

New and Used Microecopge stantly. This air is preheated in tubes passing

through water jacket.for i~Mnxlate Aivo 98% Usable Capacity: Practically no space is wasted by

heaters or controls, or by "hot and cold spots."

For further information on these Castle Precision Incu-17 Eadt 40th Street bators, write: Wilmot Castle Co., 1212 University Ave.,

Rochester 7, N. Y.NEW YORK is. N. Ye C

. * i .. , . * Jo Aft-Sl. D;,..* | 10 a-stle BACTERIOLOjG-I'CA APP' TUS

17

Page 8: DECEMBER BAUSCH LOMB - Science | AAAS · BAUSCH & LOMB BALOPTICON MODEL B This ... and brought under one general principle and solution-statistical procedures associated 261by 8*

18 SCIENCE-ADVERTISEMENTS VOL. 102, No.

INCREASED EFFICIENCY; ADDS PLEASURE TO YOUR WORK

TIP TOUCH

rib -s

HOSPITALS \

uced Prices...IRESCENT DESK LAM

(COOM P LET E)

NOW

ONLY$°Immediate Delivery

CLAMPS ON OR SCREWS ON to any horizontal,vertical or sloping surface, or drawing board, desk or

machine tool.FOR DRAWING BOARD ONLY, a special undersideconnection is furnished in place of the regular clamp.

ORDUJER NOWIMMEDIATE DELIVERY

I:

S+ . , @0, @0a; -E;, .;0iUS041In~~~~~~~~~~

_ u~~~.AARIST

_Z| t _~~~~~~~~~~~~~~~a_E g~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~row sw~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~an18 SCIENCE-ADVERTISEMENTS VOL. 102p No. 2659

i-7 .RTISTS_

Page 9: DECEMBER BAUSCH LOMB - Science | AAAS · BAUSCH & LOMB BALOPTICON MODEL B This ... and brought under one general principle and solution-statistical procedures associated 261by 8*

DECEMBER 14, 1945 SCIENCE-ADVERTISEMENTS 19

Eimer and Amend's new Chemical Manufacturing Plant at Edgewater, N. J.

Additional Facilities for Producing

FINE CHEMICALS

and Special Reagents for Laboratories

The chemical manufacturing facilities recently established by Eimer

and Amend at Edgewater, N. J., supplement those operated at its

Greenwich Street Plant. This increased manufacturing capacity,

together with the large and comprehensive stocks on hand, enablesE. and A. to meet the growing needs of America's laboratories for

E. 4 A. Tested Purity analytical reagents and special chemicals.Reagents meet specifi-cations of the A. C. S.-the exact analysis Special Preparations for Laboratory and Industrial Useis stated on each label.

Manufacturers-Distributors

FISHER SCIENTIFIC CO. E lM E R A N D AM E N D717 Forbes St., Pittsburgh (19), Pa. CL Greenwich and Morton Streets2109 Locust St., St. Louis (3), Mo. New York (14), New York

Headquarters for Laboratory Supplies

DECEMBER 14, 1945 SCIENCE-ADVERTISEMENTS 19

Page 10: DECEMBER BAUSCH LOMB - Science | AAAS · BAUSCH & LOMB BALOPTICON MODEL B This ... and brought under one general principle and solution-statistical procedures associated 261by 8*

20 SCIENCE-ADVERTISEMENTS

rFOR ELECTRONIC, OPTICALAND SCIENTIFIC APPARATUS

WE specialize in the production of5front or fear surface mirrors, mode toyour specifications. Closest optical anddimensional tolerances observed.

Because of their proven superiority.ZENITH mirrorsare preferred by many

leading manufacturers ofprecisionequipment. _rcsl

! EXCEPTIONAL REFLECTIVITY 0 PERMANENT CHARACTERISTICSALUMINUM. SULVER. GOLD. etc.

_OPAQUE 0O SEMI-TRANSPARENT * PROMPT SERVIClEWe Invite your inquiry. Samples andlquotations will be submitted promptly.

I.11,1:Sad, 13sjj1v1

1(+)ARGININEMONOHYDROCHILORIDE

K T

GUANINETil!MIEARI CORPOAIOW

Ghemica/~ 4M WAVERLY PEWO1o153 WAVERLY PLACE, NEW YORK 14, N.Y..

. a1-01.8

Bacto-AgarBacto-Agar is a purified

Agar prepared from domes-tic material. In the manu-facture of Bacto-Agar ex-traneous matter, pigmentedportions, and salts are re-duced to a minimum, so thatthe finished product in theform of fine granules willdissolve rapidly, giving clearsolutions.

DIFCO LABORATORIESINCORPORATEDDETROIT 1, MICHIGAN

a 1

~ ~ ~ ~ ~ ~ ~ - -a

LK ii

VOL. 102, No. 265920 SCIENCE-ADVERTISEMENTS

1

Page 11: DECEMBER BAUSCH LOMB - Science | AAAS · BAUSCH & LOMB BALOPTICON MODEL B This ... and brought under one general principle and solution-statistical procedures associated 261by 8*

In

I N TH E M A R K E T P L A C ERATES to be paid in advance. Regular stng 10¢ a word, minimum charge $2.00 each; count 8 words if a box address is usedDislay, 3 inches maximum, $8.80 per column inch. No discounts or commissions.SEND advertisements with remittance to the ADVERTISING DEPARTMENT, American Association for the Advancement of Science,AMERICAN UNIVERSITY, MASSACHUSETTS AND NEBRASKA AVENUES, WASHINGTON 16, D. C. Correct remittancemust accompany instructions and copy and advertisements will be published in sequence of completed orders.

REPLIES to box number advertisements should be sent to the Advesing Department for forwarding.

DUU^ODBiI55Journals, Periodicals, Serial Publicatlons-Sets, runs andsingle volumes bought and sold. Entire libraries purchased.J. S. CANNER COMPANY, Boston 15, Mass.Wanted to purchase-Scientific Periodicals, sets and runs,Foreign-Domestic. Entire libraries and smaller collections.WALTER J. JOHNSON, 125 East 23rd Street, New York 10,N. Y.For Sale-Chemical Medical and Scientific Periodicals-Volumes and Back iopies. B. LOGIN & SON, INC., Est. 1887.29 East 21st St., New York 10, N. Y.Assistant Chief Chemist-Large midwestern PharmaceuticalCompany has immediate opening for man to develop analyti-cal procedures and direct analytical control work. Box 318,SCIENCE.Research position for a Ph.D. organic chemist with bio-chemical background. Work on a "hot" problem. SoundMidwest commercial organization. Box 319, SCIENCE.Opportunities Avallable-(a) Assistant or instructor in phys-iology; teaching duties occupy third of time, remainderbeing free for research or conducting other courses in uni-versity; $2,000-$3,000 for eleven-month session. (b) Bio-chemist to become associated with department of pathology,500-bed hospital; must have more than routine training inblood chemistry; vicinity New York City. (c) Bacteriologistqualified to assume responsibility of manufacture of vac-cines, toxoids and serums; preferably one experienced incommercial work, control with working knowledge of Regu-lations of the National Institute of Health; salary up to$5,000. (d) Young physician to join staff of department ofclinical research, large pharmaceutical company; duties con-sist of working with new products evaluating clinical effectsand following up results; possibility of some medical writ-ing; traveling would involve only 25% of time; headquartersin Middle West. (e) Research chemist experienced in in-dustrial field; research covers biochemistry, organic andphysiological chemistry; preferably some one who can de-velop into position of director of research chemistry; $4,000-$5,000; East. S12-2 Medical Bureau (BURNEIcE LARSON,Director), Palmolive Building, Chicago 11.

Opportunities Wanted-Biochemist; Ph.B., M.S., Ph.D. de-grees, eastern schools; graduate training principally inmammalian physiology and biochemistry as related to en-docrine function; several years' successful teaching experi-ence followed by record of interesting experience as head ofresearch in large institution; for further information, pleasewrite BURNEIcE LARSON, Director, Medical Bureau, PalmoliveBuilding, Chicago 11.Bacteriologists Biologists, Physiologists, Chemists, Pharma-cologists, Physiotherapists, Laboratory Technicians, let ushelp you secure a position. Our service, established 1898,Is nationwide. Write us today. All information confidential.AZNoE'S-WOODWARD BUREAU, 30 North Michigan, Chicago 2.Inventor seeks connection with organic chemist or malehormone researcher with laboratory. Box 317, SCIENCE.Research Chemical Engineer-Librarian. Research and de-velopment experience in several branches of the plastics in-dustry. Recently organized and directed diversified techni-cal library serving 100 research men. Master's degree, 1922.Protestant. Am seeking permanent research, development,or library position where my training experience and ideaswill be worth $5000 to start. East boast preferred. Box315, ScIENcE.

SUPPLIES AND EQUIPMDENT%" Discs for the Assay of Penicillinand other Antibacterial Substances

No. 740-E.

Schleicher & Schuell Co.I] Plant and Lab: South Lee, Mass.

Head Office: 116-118 West 14th St.New York 11, N. Y.BALANCES RlEPAIRED

All work guaranteed; parts available;balances insured while mn our factory.Send for price list. Free use of specialshipping crates with complete packinmaterials, etc.Laboratory Equipment

Repaired d ReflnieheBECKE}R BALANCES, INC.

481 Min St. New Rocheie, N. Y."4th Generation of Service

and Integrity"M I C R O S C O P E SMEDICAL-INDUSTRIAL-AMATEUIRSupplies-Accessories-Scientific Instruments

SPENCER NEW and USED ZEISBought-Sold-Exchanged-Repaired

Send for FREE LISTNATIONAL SCIENTIFIC INSTRUMENT COMPANY

119 chame St. Phie BA.7-9234 New York Cit 7

POSITIONS OPEN

PHARMACEUTICAL CHEMISTLarge midwestern pharmaceutical firm needsa Ph.D. or the equivalent to direct formula-tion of new pharmaceutical products. Veryresponsible position pertaining to the de-velopment. of new pharmaceutical dosageforms. Men with experience in the manu-facture of tablets, ointments and relatedproducts will be given preference.

Box 313, SCIENCE

POSITIONS WANTED

WE WANT APHYSICIST

To join our expanding research and developmentstaff in Washington not later than Jan. 15. Weprefer a man with recent experience on one of theManhattan Projects. This man should be able

* To handle the mathematics that goeswith advanced nuclear physics.

* To visualize practical applications re-sulting from his research.

* To direct others in carrying out hisideas.

To the right man we can offer a good starting sal-ary and plenty of opportunity. If you want to beassociated with a young organization and youngmen who are going places, send us a detailed letterof application about your education, experience,publications and/or patents, marital and draftstatus, and salary expected, with a recent photo.

Box 312A, SCIENCE

irb^^lwd=lwlr ir iwimo irb^ownnw^wcx ^ithimILY

W.

400

Page 12: DECEMBER BAUSCH LOMB - Science | AAAS · BAUSCH & LOMB BALOPTICON MODEL B This ... and brought under one general principle and solution-statistical procedures associated 261by 8*

SCIENCE-ADVERTISEMENTS,,.s,* @ . ~ ~

Eaer. ..to see for themselves . . . to d outwhat- happens- and why... Childrenare like that when they handle a micro-scope. Ea~ger! Aproaching a new world,a wide. ~wake mind finds magic andmeaning in the specimen. And eagernessto learn is the key to, better learning.,Idea"for irgh school science courses.the Spencer Nb. 66 Microscope is large

and durably btiit. It provide& the neces-sary mechanical ,features-coarse andfine adjustment, revolving- disc dia-phragm, revolving nosepieCCand opticsidentica-l to thoge ,r on standardlaboratoqryii ,,ias. c.

from 24X to 440X cover the range need-ed for biology.The price of $80.,00 inciudes two ob-

,jectives, two eyepieces, two objectiveboxes and cabinet.---

Spencermicroscopesareavailablefromscientificinsrument distributors through-out the world. Further information canbe obtained by writing Dept. Z 2.

American P OpticalScientific Instrument Division

Buffa(6-1', NewYorrk

79?aui/da~-c '$ SPENCER J

22 VOL. 102. No. 2659