NOVEMBER 16, 1945 SCIENCE-ADVERTISEMENTS

440

ESSENTIALS OF HUMAN EMBRYOLOGYBy GIDEON S. DODDS, Professor of Histology and Embryology, School of Medicine,West Virginia University

Extensively revised, this third edition retains the plan and ideals of earlier volumes but includesrecent advances in embryological knowledge. The chapter on early development is wholly new.

Other sections which have been rewritten are those dealing with the fetal membranes, the earlymesoderm, the organs of respiration, the body cavities, the blood vascular system, the lymphatics,the reproductive organs and the organs of special senses. New illustrations have also beenadded. December 1945.

Approximately 310 pages; 5% by 8%; Probable price $4.00

AERIAL NAVIGATIONBy H. E. BENHAM, Director of Ground Training, Pan American-Grace Airways, Inc.

This book is designed to provide students of aerial navigation with practical material for use intheir study of a practical science. Simple yet complete, it explains the latest techniques in thefield and includes problems applying theory to actual cases. The book is suitable for use incollege courses and in airlines' pilot training courses. November 1945.

344 pages; 5% by 8%; $4.00

ELECTRON OPTICS AND THE ELECTRON MICROSCOPEBy V. K. ZWORYKIN, G. A. MORTON, E. G. RAMBERG, J. HILLIER, A. W. VANCE;All at BCA Laboratories, Princeton, N. J.

This comprehensive book covers the electron microscope in all its phases. The material was

chosen to fulfill a two-fold purpose. The first is to aid the present or prospective electron micros-copist in understanding his instrument and using it to greatest advantage; the second, to pre-sent systematically the practical and theoretical knowledge which must form the basis for furtherprogress in electron microscope design. December 1945.

Approximately 759 pages; 5% by 8%; Probable price $10.00

INTRODUCTION TO ORGANIC CHEMISTRYBy ALEXANDER LOWY, Late Professor of Organic Chemistry, University of Pittsburgh,BENJAMIN HARROW, Professor of Chemistry, and PERCY APFELBAUM; Both atCity College, College of the City of New York

Thoroughly revised, this new edition has much additional material, a more extended discussionof the electronic concept of valence, and includes such topics as resonance, substitution in thebenzene ring, alicyclic ring structures and high polymers. The chapter on terpenes has beenrewritten and the list of references revised. October 1945.

Sixth Edition; 448 pages; 5% by 8%; $3.50

PLANE AND SPHERICAL TRIGONOMETRYBy H. A. SIMMONS, Professor of Mathematics, Northwestern University

This greatly enlarged second edition begins with the trigonometric functions of the generalangle, instead of the positive acute angle, and includes precisely the solid geometry needed forthe study of spherical trigonometry, The book contains not only theoretical spherical trigo-nometry, but a large number of applications, including introductory navigation and certain ele-mentary problems of astronomy. There are also chapters on Complex Numbers and the SlideRule. September 1945.

Second Edition; With tables; 519 pages; 5% by 8%; $3.00Without tables; 389 pages; 55/8 by 8%; $2.25

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THE SUN'S RADIATION AND THE WEATHERWEATHER changes on earth may be indirectly con-

trolled by changes in the sun's radiation, through varia-tions in the thickness of the radio-wave-reflecting "E"layer of the earth's outer atmosphere. A close correla-tion between thickness changes in this layer and shifts inthe weather has been found by Dr. Charles G. Abbot,research associate of the Smithsonian Institution, in a

study of records extending over seven years.

Dr. Abbot has for many years followed the apparentconnection between the weather and the solar constant,or total radiant energy received from the sun, as reeordeddaily at Smithsonian observatories in California, NewMexico and Chile. Changes in the solar constant are smalland difficult to make at best-impossible under badweather conditions. "E" layer thickness variations, on

the other hand, are easier to measure and observationsare not affected by weather. These thickness variationsare also measured daily, by observers of the Carnegie In-stitution of Washington; the best records are those keptby the Carnegie stations in Huancayo, Peru, and Wath-eroo, Australia."It is clear," according to Dr. Abbot, " that the sun 's

variations are a major factor in weather. The effectsproduced are large. In Washington temperatures itmakes nearly 20 degrees Fahrenheit of difference in some

months whether the solar constant rose or fell by threefourths of one per cent. a week or more previously. Theeffects are long continuing. They appear to begin threedays before measurable changes in radiation occur, and tolast at least until fourteen days after, making an impor-

tant sequence of at least 17 days in weather, attendingeach change of solar radiation."It appears that approximate predictions a week in

advance could be made of dates of peaks and troughs ofWashington temperature if daily reports of the 'E'layer were obtained from a sufficient number of ioniza-tion stations, and if means could be found to anticipateby a few days closely the date of the next approachingsolar change. Its sign would always be known to beopposite to that last observed. From present. records we

should expect solar changes of the same sign to followeach other at intervals of about nine days, with changesof opposite sign intervening. There is, I think, a fairhope that such important dates as heavy frosts may

become predictable a week in advance from solar obser-vations by this method."

ITEMSTHE Smyth report on atomic energy, which is the

authorized detailed story of the development that led tothe atomic bomb, has been reprinted in a 10,000-editionby His Majesty's Stationery Office, the official British

government agency corresponding to the U. S. Govern-ment Printing Office which prints U. S. official publica-tions. About ten such U. S. documents have been pre-printed similarly, including the official radar report. TheAmerican Library in London, which is a function of the

VOL. 102, No. 2655

Department of State, acts as professional adviser to theHMSO in this connection.

RETURN of science in Norway to normal conditions issignalized by arrangements now being made for a geo-

logical research expedition into a high mountain area inthe central part of the country, to study records left inthe rocks and soil by the waning remnants of the lastgreat Ice Age glacier. A communication to this effecthas just been received here by the Geological Society of

America from Dr. Kaare Munster Strom, president of theGeological Society of Norway. The expedition, whichwill be in the field from about June 25 to July 5, willbe under Dr. Strom's leadership. The size of the partywill have to be limited because of lack of shelter in therugged mountain country, but two or three Americangeologists may be included.

A SHIPMENT of 800 fingerling carp has been sent bythe U. S. Fish and Wildlife Service to stock lakes andstreams in the neighborhood of the American air base on

Trinidad, off the northern coast of South America. Thecarp is an exceedingly adaptable and prolific fish, andeven a small planting like this has a good chance of be-coming established. Introduced from Europe, the carp

has never found much favor in this country. It is closeto the bottom of the American market in order of prefer-ence as a food fish, and sportsmen generally consider ita pest. One virtue is grudgingly conceded to it: carp

will survive in waters too polluted for any other species.Yet many peoples elsewhere in the world are very fondof it, and it has a long and honorable table history.Roman patricians used to have private carp ponds attheir country villas, so that the fresh-caught fish couldbe carried directly to the kitchen.

A NEW industrial science research center under con-

struction at Bound Brook, N. J., is another bit of evi-dence of appreciation by American industrialists of thepart science played in winning the war, and the in-creasingly important part scientists will play in Amer-ican manufacturing. The building under construction isthe first unit of a gigantic center to carry on researchwork in the field of building materials. It is being erectedby the Johns-Manville Corporation. A unique feature ofthe first building of the group planned, a $2,000,000structure, is that it will contain central laboratories andten experimental factories. Projects initiated in thelaboratories may thus be carried through their develop-ment and pilot-plan production stages under one roof.This is expected to speed up the development of new andimproved materials for building and for industrial uses.

The completed research center, if constructed accordingto present plans, will include six.buildings on a 93-acre

plot, across the Raritan River from the company's plantat Manville. They include two laboratory-factory struc-

tures, a research engineering and machine shop building,a water-filtration and waste-processing building and

utility buildings.

SCIENCE-SUPPLEMENT

SCIENCE NEWSScience Service, Washington, D. C.

NOVEMBER 16, 1945 SCIENCE-ADVERTISEMENTS 13

SMALL FRUIT CULTUREBy

JAMES S. SHOEMAKER, PH.D.1 Professor of Horticulture, University of Alberta

52 Illustrations-434 Pages-$3.50

Bigger and better yields are assured the small-fruit grower who utilizes the richmaterial presented in this book. An experiment station teacher and horticulturistof prominence discusses the problems of small-fruit growers in every section of thecountry and presents facts, not generally known, that can be highly profitable to thegrower. To traverse its pages is to gain a wide experience in small-fruit culture-and it is a book that can be read as well as studied.

The culture of grapes, currants, blueberries, cranberries, gooseberries, 'dewberries,raspberries, blackberries, loganberries and strawberries are discussed.

"It is an extremely useful reference book with its encyclopedic fund of facts con-cerning small fruit culture in the United States."-Journal of the Ministry ofAgriculture.

"Teachers and students in our colleges of agriculture, small-fruit growers, researchworkers, and others will feel indebted to the author for having brought together muchuseful information."--Soil Science.

Synopsis of the studies under each cultureThe Industry, Regions, DistrictsDevelopment of VarietiesCharacteristics of VarietiesDuration of Plantings, Yields and CostsPropagationLocation and SitePlantingSystems of TrainingRemoving the Flower Stalks

TillageIrrigationMulching and Winter ProtectionFruit-bud FormationLength of Fruit-Development PeriodFertilizersRenewed PlantingsHarvesting and MarketingControlling Diseases and Insects

THE BLAKISTON COMPANY - Philadelphia 5, Pa.

NovEmBEF. 16, 1945 SCIENCE-ADVERTISEMENTS 13

14 SCiENCE-ADVERTISEMENTS VOL. 102, No.

1Ze~#ed e 7t(44#-w'dt sGlHANDBOOK OF METEOROLOGY

Edited by F. A. BERRY, JR., Captain, USN; E. BOLLAY, Lieut. Comdr., USNR; and NORMANR. BEERS, Lieut., USNR. 1116 pages, 51 x 81, 730 illustrations. $7.50

The most complete work of its kind ever published, thishandbook covers all the material usually given to studentsin comprehensive training programs in meteorology, in-cluding mathematics; thermodynamics; physics of the

air; radiation; descriptive meteorology; climatology; dy-namic meteorology; instruments; codes, maps, and plot-ting; synoptic meteorology and weather forecasting;oceanography; and hydrometeorology.

ELECTRONICS DICTIONARYBy NELSON M. COOKE, Lieut. Comdr., USN, Executive Officer, Radio Materiel School, NavalResearch Laboratory, Washington, D. C., and JOHN MARKUS, Associate Editor, Electronics.433 pages, 51 x 81, 610 illustrations. $5.00

Here is an up-to-date, well illustrated glossary containingclear-cut and accurate definitions of nearly 6,500 termsused in radio, television, industrial electronics, communi-cations, facsimile, sound recording, etc. This compilation

of authoritative, readily understood definitions constitutesthe most comprehensive dictionary of its type available.There are 610 appropriate diagrams and sketches whichgreatly enhance the book's usefulness and interest.

SEX AND THE SOCIAL ORDERBy GEORGENE H. SEWARD, Assistant Professor of Psychology, Connecticut College. McGraw-Hill Publications in Psychology. 286 pages, 51 x 8. $3.50

Fills a serious gap in the literature of the biological andsocial sciences. Presents a comparative study of the partplayed by sex in representative social organizations fromfish to man. Sex is consistently viewed within the frame-work of the society as a whole. Progress from lower to

higher forms of life is shown to be associated with a shiftin the balance between biological and social determinersof sex behavior. The material is based on experimentaldata, supplemented by clinical cases and anthropologicalfield studies.

X-RAYS IN PRACTICEBy WAYNE T. SPROULL, Physicist, Research Laboratories Division, General Motors Corpora-tion. In press-ready in December

An authoritative and comprehensive treatment, giving thestudent a broad understanding of x-rays, their nature,and the many purposes for which they may be used. Thebook deals with the generation, absorption, scattering, etc.,of x-rays, measurement and recording of x-rays, x-ray

equipment, industrial radiography, medical applications,x-ray diffraction and crystallography, electron diffraction,fluoroscopy, automatic inspection, microradiography, gemcoloration, etc.

GENERAL CHEMISTRYBy JOHN ARREND TIMM, Professor of Chemistry and Director of School of Science, SimmonsCollege. International Chemical Series. 691 pages, 53 x 83, 185 illustrations. $3.75

This superior new textbook has started upon a successfulcareer, and has already been adopted by over 50 collegesand universities. Written in a vigorous, almost conver-sational style and firmly based on sound scientific andpedagogical principles, General Chemistry presents things

clearly and graphically in a vivid manner that gives zestto the course and inspiration to the student. One of thefeatures of the text is the thorough, modern treatment offundamental theory.

Send for copies on approval

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

14 SCIENCE-ADVERTISEMENTS VoL. 102, No. 2655

NOVEMBER 16, 1945 SCIENCE-ADVERTISEMENTS 15

ECOLOGICALCROP GEOGRAPHY

By Karl H. W. Klages

"We heartily recommend this book to ento-mologists and others who are interested inthe phase of plant ecology which has to dowith crop plants."-Annals of the Ento-mological Society of America. "Ecologistswill be grateful for the writing and publica-tion of this book."-Ecology. "A decidedcontribution . . . should prove of inesti-mable worth to students, teachers, and spe-cialists having to do with long range agri-cultural policy."-Rural Sociology. Forcourses in crop production and crop ecol-ogy. $4.50

THE EARTHAND MANBy D. H. Davis

"A fascinating presentation of the subjectthat is worth the attention of every geog-raphy teacher."-Amer. Geographical So-ciety of N. Y. "The best book available inits field."i-Annals of the Amer. Academyof Political & Social Science. "A veritablemine of geographical knowledge . . . judi-ciously selected and painstakingly authenti-cated.... An excellent book in every way."-Economic Geography. Covers both phys-ical and economie geography. For the in-troductory course in geography on the col-lege level. $4.25

GEOMORPHOLOGYSystematic and Regional

By 0. D. Von Engein

"An outstanding contribution to one of thefields of geomorphic investigation of mostpractical present importance."-Tl. of Ge-omorphology. "One of the most valuableand timely contributions to the field of'geoscience' that has come from the Ameri-can press these many decades.... Sure to

take first place among the American text-

books on geomorphology, and to hold thatplace for many years."-Economic Geog-raphy. Gives the thorough basic trainingin geomorphology necessary for all kinds ofgeologic, survey and map work. $4.50

NATURE ANDPROPERTIESOF SOILS

By Lyon and Buckman

"Valuable, timely, and up-to-date."--TI. ofthe Amer. Society of Agronomy. "Valu-

able from every point of view ... will con-

tinue to fill a much felt want for those in

the many diverse fields of agriculture, biol-ogy, and geology."-Quarterly Review ofBiology. Widely used in agricultural col-

leges as the regular prerequisite for all

courses in crops and plant science. 4th

Ed., $3.50

NovEMBER 16, 1945 SCIENCE-ADVERTISEMENTS 15

16 SCIENCE-ADVERTISEMENTS VOL. 102, No. 2655

How Westinghouse STRATOVISIONtook the final headache out of Television and F. M.

EVEN before the war ended,Television and FM transmit-

ting and receiving equipmenthad reached a high degree ofperfection. But a final difficultyremained-the problem of broad-casting such programs on anationwide basis.Because of the ultra-high fre-

quencies employed, Televisionand FM waves travel only instraight, "line - of - sight" direc-tion. They do not bend aroundthe earth's surface . . . as dothose of standard-band radio.This limits the range of a

Television or FM station to about50 miles-even when perched atopthe tallest building.A chain of radio-relay stations

across the country - or coaxialcables spanning the nation-havebeen proposed as a solution. Butthese are terrifically expensiveand, worse yet, cause serious dis-tortion of long distance programs.Now, at last, Westinghouse re-

search engineers have discov-ered a practical solution through"STRATOVISION" - broadcastingTelevision and FM programs

from planes flying six miles highin the stratosphere!At this altitude, a single Strat-

ovision plane can cover an area422 miles in diameter... 103,000square miles . . . approximatelythe combined area of New York,New Jersey and Pennsylvania.

Westinghouse engineers pre-dict that 14 of these flying broad-casting stations can transmit 4Television and 5 FM programssimultaneously to 78% of thenation's population.The conception and planning

of Stratovision broadcasting area tribute to the ingenuity andengineering "know-how" ofWestinghouse radio technicians... gained through producing ap-proximately $400,000,000 worthof Radar and radio equipmentfor our armed forces.

HERE'S THE SECRET . . . Stratovisionbroadcasting, serving an area of 103,000square miles, will require only 7/50thas much power as a 50 kilowatt groundtransmitter covering only 7,900 squaremiles. That's why a single Stratovisionplane can easily carry and power theequipment needed for simultaneously trans-mitting 4 Television and 5 FM programs.

WestinghousePLANTS IN 25SCITIS OfFICES EVERYWHERE

Tune in: JOHN CHARLES THOMAS-Sunday, 2:30 pm, EST, NBC.TED MALONE- Monday through Fr.day, 17:45 am, EST, American Network

16 SCIENCE-ADVERTISEMENTS VOL. 102. No. 2655

NOVEMBER 16, 1945 SCIENCE-ADVERTISEMENTS 17

cAnnouncing

JOURNAL OF COLLOID SCIENCEThe Editors: T. R. Bolam, Edinburgh; E. F. Burton, Toronto; R. M.-

Fuoss, New Haven; H. R. Kruyt, Utrecht; J. W. McBain, StanfordUniversity; E. K. Rideal, Cambridge; William Seifriz, Philadelphia;A. W. Thomas, New York; Arne Tiselius, Upsala; Harry B. Weiser,Houston.

The Consulting Committee: W. T. Astbury, Leeds; J. J. Bikerman,New York; W. Clayton, Orpington, (England); P. Debye, Ithaca;W. Feitknecht, Berne; Alexander Frumkin, Moscow; William D.Harkins, Chicago; Ernst A. Hauser, Cambridge; Wilfried Heller, Chi-cago; Hans Jenny, Berkeley; S. S. Kistler, Worcester; H. Mark,Brooklyn; J. N. Mukherjee, New Delhi; F. F. Nord, New York; TheSvedberg, Upsala.

IT is with great pleasure that we present the first journal on colloid sciencein the English language-a publication which has been heartily welcomed

by specialists both here and abroad. The list of Editors and Members of theConsulting Committee will at once indicate the broad scope of the journal.We hope that this publication specializing in problems of colloids and surfacephenomena will make it easier for the members of research laboratories tofollow up the development of science and to find inspiration for its application.

Manuscripts shoidd be submitted to the Editorial Office of the Journal of Colloid Science,125 East 23rd Street, New York 10, New York. Foreign contributors may submit theirpapers to the nearest Editor abroad.

Subscription: The Journal of Colloid Science will be published bimonthly priced at tendollars a year. The first issue is scheduled for January, 1946.

ACADEMIC PRESS INC., PUBLISHERS125 East 23rd Street, New York 10, N. Y.

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NOVEMBER 16, 1945 SCIENCE-ADVERTISEMENTS 17

18 SCIENCE-ADVERTISEMENTS 2655

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Indophenol Indigo Monosulfonate2-Chloro Indophenol Indigo Disulfonate2-Methyl Indophenol Indigo TrisulfonateMethylene Blue Indigo Tetrasulfonate

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* Available in tablet form for Vitamin 0 work.LaMotte Chemical Products CompanyDept. "H" Towson 4, Balthmore, Md.

HEBIG AND AFTER LIEBIGA Century of Progress inAgricultural Chemistry

A symposium organized and presentedby the Section on Chemistry of the Asso-ciation under the direction of a specialcommittee: Charles A. Browne, RichardBradfield, and Hubert B. Vickery. Thereare four papers under the heading of Or-ganic Chemistry, Enzymes and Nutritionand five under the heading of Soils, Ferti-lizers and the Mineral Requirements ofPlants.

viii + 111 pages (7 x 1),14 illustrations, references, cloth binding;

published in 194.2Price, $2.50; price to non-members

of the Association, $3.00.

American Association for theAdvancement of Science

Smithsonian Institution BuildingWashington 25, D. C.

If you* Need instruments or equipmentrepaired -

* Want to sell your collections ofscientific books or periodicals

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Consult the firms who advertise their services

IN THE MARKET PLACE

18 SCIENCE-ADVERTISEMENTS VoL. 102, No. 2655

IN T H E M A R K E T P L A C ERATES to be paid in advance. Regular setting 10¢ a word, minimum charge $2.00 each; count 8 words if a box address is used.Display, 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.

PERIODICALS

Wanted to purchase Scientific Periodicals, Foreign-Do-mestic. WALTER J. JOHNSON, 125 East 23rd Street, NewYork 10, New York.

SUPPLIES AND EQUIPMENT

Experimenters-500 useful valuable new springs, 150 kinds;numerous sizes, 1/32 to 10 inches; expansion, compression,torsion, etc. Ideal for experiment, models, repair. $5.00.Super assortment, $10.00. Smaller assortment, $3.00. Satis-faction guaranteed. TECHNICO, Box 246-X, West Hartford,Conn.

to Purchase: Polarimeter. Submit make, details,C. INTERCHEMICAL CORPORATION, Biochemical Divi-lon, N. J. Unionville 2-5200.

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POSITIONS OPEN

Opportunities Avaiable-(a) Bacteriologist with some abilityin fields of hematology and hospital laboratory chemistry;to take charge of diagnostic laboratory In hospital, unit ofuniversity group; would be accountable for all bacteriologi-cal diagnostic procedures; hematological and chemical stud-ies done by others; would be responsible for running de-partment efficiently. (b) Pharmacologist or chemist to serveas liaison officer between research and manufacturing de-partment of large pharmaceutical company; competentadministrator required; $6,000. (c) Physiologist; youngman of pre- or post-doctoral caliber to participate in funda-mental research program on epithelial tissues; training orexperience in tissue studies and interest in biophysical re-search methods required; East. (d) Assistant professor inphysiology; half time available for research with completeautonomy; teaching duties involve sharing the responsibilityfor the regular courses of physiology for students of collegeof medicine with other member of department; preferablyphysician with Ph.D. degree in physiology; Ph.D. withoutmedical degree eligible however. (e) Scientist with advancedtraining and background in biological sciences to becomeassociated with nationally known publishing company; du-ties consist of handling vocabulary material and technicalliterature preference for man with breadth of training andknowledge in zoology or botany. S11-2 Medical Bureau(BURNEIcE LARSON, Director) Palmolive Building, Chicago 11.Drug Products Development. Pharmaceutical manufacturerIn Northern New Jersey wants a pharmacist, pharmaceuticalchemist, or physician with previous pharmaceutical trainingto develop new drug products, Improve existing preparations,practical formulation and develop new uses. Salary open.Reply, enclosing photograph and personal data. Box 297,"SCIENCE," Advertising, Smithsonian Institution Building,Washington 25, D. C.Permanent Medical Publishing House needs man-respon-sible, permanent position in medical text book promotion,expanding department. Office New York-visit school parttime. Woman-medical editor, secretary. Salary accordingto experience. Box 303, "SCIENcE," Advertising, SmithsonianInstitution Building, Washington 25, D. C.Medical Copywriter. Pharmaceutical manufacturer in North-ern New Jersey wants physician as medical advertising ex-ecutive for copywriting, preparation of clinical articles, andpromotional activities. Previous pharmaceutical training ormanufacturing experience desirable but not necessary. Rec-ord of medical practice desirable. Salary open. Reply,giving personal data. Box 298, "SCIENCE," Advertising,Smithsonian Institution Building, Washington 25, D. C.

POSITIONS WANTED

Psychiatrist, 40, Diplomate American Board, experienrcedwith child guidance and mental hygiene, leaving Armyshortly, desires appointment in community or college clinicwith teaching opportunity, Northeastern area preferred.Box 286, "SCIENcE," Advertising, Smithsonian InstitutionBuilding, Washington 25, D. C.

The California Medical Bureau, Agency, for scientific and laypersonnel in medicine, biology, chemistry, physics, and alliedsciences, supplies teachers, research workers, laboratorydieners, skilled office help. Prompt service. Registrationfree. Your patronage respectfully solicited. THE CALI-FORNIA MEDICAL BUREAU, Agency, 595 East Colorado Boule-vard, Pasadena 1, California.

Physicist-Chemist-Applied Mathematician. Age 31, B.S.4 years Industrial chemistry, 7 years applied mathematics.Know photography, bacteriology. Author, co-author books,papers on applied mathematics. Prefer research In bio-chemical-physics. Will consider offer In applied physics,physical-chemistry. Minimum salary $5,000. Box 301,"SCIENCE," Advertising, Smithsonian Institution Building,Washington 25, D. C.

Bateyleglsts, Biologists, Physiologists, Chemists, Pharma-cologists, Physiotherapists, Laboratory Technicians, let ushelp you secure a position. Our service, established 1896,Is nationwide. Write us today. All information confidential.AzXos's-WooDwAnD BUaRAU, 30 I4orth Michigan, Chicago 2.

Biologist, Ph.D., Princeton, recently released from duty asaviation physiologist, desires academic position. Researchin nuclear cytology. Thorough background in vertebrateanatomy, cytology, embryology and physiology. Box 304,"SCIENCE," Advertising, Smithsonian Institution Building,Washington 25, D. C.

Biochemist, Ph.D. Desires position: Industrial, research in-stitute or public health. Diversified experience Includesclinicai chemistry, carbohydrate metabolism, biochemicalmethods, Warburg manometry, industrial alcohol fermenta-tion, animal nutrition. Metropolitan New York area pre-ferred. Box 294, "SCIENcE," Advertising, Smithsonian Insti-tution Building, Washington 25, D. C.

Opportunities Wanted-Biochemist serving as head of de-partment of biochemistry and nutrition during absence ofpermanent head who is with armed forces, will be availablesoon; A.B. (major, chemistry; minor, physics), Ph.D. (major,chemistry; minor, physiological chemistry); year's fellow-ship in physiological chemistry; eleven years, professor ofbiochemistry and head of the department of chemistry inuniversity medical school located in an American depend-ency; for further information covering qualifications includ-ing bibliography, please write BURNEICE LARSON, Director,Medical Bureau Palmolive Building, Chicago 11.

I M PO R T A N TPlease note that the Advertising Department of theAssociation has moved to a new location. All inser-tions and replies should be sent to the following ad-dress effective November 19, 1945:

Advertising DepartmentAmerican Association for the

Advancement of ScienceAmerican University

Massachusetts and Nebraska Aves., NWWashington 16, D. C.

5

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INSPECTING BEARINGS ofMan-made Sapphire

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20 SCIENCE-ADVERTISEMENTS VOL. 102y No. 2655

'I 1 M =9