SCIENCE-ADVERTISEMENTS

Lassar-CohnIn Englishz

A November Offering

For nearly 40 years Professor Lassar-Cohn's Arbeitsmethoden fur Organisch-Chemische Laboratorien has been standardin the laboratories of the world.

This FIRST ENGLISH TRANSLA-TION is from the 5th (latest) Germane(lition; and is of the first volume or " Gen-eral Part" dealing with fundamentalmTiethods, such as distillation and crystal-lization, rather than with specific reactions.

It is made by RALPH E. OESPER,University of Cincinnati; and edited byROGER ADAMS and HANS T. CLARK&h

It is published as Number Two of theWorld Wide Chemical Series, publishedunder the general editorship of E. EMMETREID.

Author and editors have annotated theEnglish edition."The book is a very valuable one and

should be in every laboratory where workin organic chemistry is done" is the com-mient of the Journal of the AmericanChemical Society on the German edition.

Cloth. 6xg. xi + 458 pages.

Illustrations.

Price $6.50.

The Williams & Wilkins CompanyPublishers of Scientific Books and Periodicals

Baltimore, U. S. A.

A History ofMathematical Notations

in two volumes

by

FLORIAN CAJORI

Volume I-Elementary Mathematics, nowready. $4.00

Volume II-Advanced Mathematics, in prepa-ration. $6.oo

This study emphasizes the difficulty experi-enced even in ordinary arithmetic and algebrain reaching a common world-language. Theonly hope for rapid approach of uniformity inmathematical symbolism lies in internationalco-operation through representative com-mittees.

SEND FOR COMPLETE CATALOG

The Open Court Publishing Company339 East Chicago Avenue

Chicago, Ill.

ANALYTICAL PRINCIPLESOF THE PRODUCTION OFOIL, GAS, AND WATER

FROM WELLS

By STANLEY C. HEROLD

T HIS treatise may best be described asthe theoretical mechanics of production

from reservoirs. The author has developedthese fundamental principles from anexact analysis of the physical laws per-taining to the behavior of liquids and gases."The problems of mutual interference ofwells, recovery of oil and gas, drainage ofa pool by a well or a group of wells, andother important problems can only besolved by the application of the theory'expounded in this treatise. "-C. F.TOLMAN, Professor of Economic Geology,Stanford University.

$7.50 postpaid

STANFORD UNIVERSITY PRESSStanford University, California

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SCIENCE-ADVERTISEMENTS

NEW SCIENTIFIC BOOKS

The McGraw-Hill Book Company, Incorporated,New York

CHEMICAL PUBLICATIONS. Melvin G. Mellon. pp. viii +253. $2.50.

A survey of the available published information on chem-ical science and chemical industry. The book describesthe origin and development of chemical publications, andis a guide to the proper use of chemical books and peri-odicals.

The Macmillan Company, New YorkA LABORATORY MANUAL OF GENERAL BoTANY. Emma L.

Fisk and Ruth M. Addoms. pp. ix + 103. $1.00.

This manual is the outgrowth of a series of privatelyprinted laboratory manuals which have been in use duringmany years in the elementary courses in botany at theUniversity of Wisconsin. The general plan of the course isto introduce the subject through a study of seed plants,and to use the facts and principles learned as a basis for acomparative study of the main groups of the plant kingdom.

Harcourt, Brace and Company, New YorkHUNGER FIGHTERS. Paul de Kruif. 377 pp. $3.00.

By the author of " Microbe Hunters." The story of a fewforgotten men struggling with nature to maintain and in-crease the North American food supply. The author trav-eled from one end of the country to the other and it waswith difficulty that the record and intimate story of thedeeds of those still living was obtained.

The World Book Company, Yonkermon-Hudson,New York

OBJECTiVE TESTS. Jacob S. Orleans and Glenn A. Sealy.pp. x + 373. $2.20.

Just how to prepare and use the new-type examinationsin order to realize their educational advantages is shownin this book.

The University of Chicago Press, ChicagoABSTRACTS OF THESES. pp. xi + 461. $3.00.A collection of abstracts of theses written in various de-

partments of the Ogden Graduate School of Science for

1926-1927.

The Johns Hopkins Press, Baltimore

DEVELOPMENT OF GOVERNMENTAL FOREST CONTROL INTHE UNITED STATES. Jenks Cameron. pp. viii +471. $3.00.

A story of the conflict between the two principles of free-dom and control in connection with the forests in thiscountry.

D. Van Nostrand Company, Incorporated, New YorkAMERICAN CHIEmISTRY. Harrison Hale. pp. ix + 255.

$2.50.This book seeks to be of service both to the general

reader and to the reader still in school. For the student itis intended for use either as collateral reading along witha course in general chemistry or as a short separate course.For both courses the author has used this material satis-factorily in his classes.

Max Niemeyer Verlag. Halle, (Saale) Germany

TYPES OF MEN. Eduard Spranger. Translated fromthe German by Paul J. W. Pigors. pp. xii+402.$4.00.

This book attempts to carry out a new method of differ-entiating human types, especially types of the soul.

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Marine Biological LaboratoryWoods Hole, Mass.

SUPPLY Biological SuppliesDEPARTMENT

For the classroom, museum or col-Open the Entire lector.

Look for the sign of the Limulus.Year As the Limulus represents the test

of time, we feel from the businessgrowth that our supplies have alsostood the test of years.

Send for Cataloguet,&ST or

No. I. Zoological and Embryolog-ical material. Life Histories andHabitat Groups.No. II. Botanical materlal.No. Microscopic Slides.

Address ail correspondence regard-Ing material and catalogue to:

Supply Department

GEO. M. GRAY, Curator,

Woods Hole, Mass.me

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NATURAL HISTORYSPECIMENS AND MODELS

We have been getting together specimensfor over fifty years, so are in an exceptionalposition to supply material for the follow-mg sciences:

Mineralogy, Geology, Paleontology,Conchology, Ornithology, Zoology,

and EntomologySome of our recent circulars are

S-276 Mineral and Rock CollectionsS-243 Krantz Crystal ModelsS-271 Relief MapsS-286 Interesting FossilsS-24I Microscope Slides of ParasitesS-279 Skeletons and Dissections of Typical

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ImportanceS-234 Insect CollectionsS-222 Collection for Teaching ZoologySC-41 Microscope SlidesSC-42 Entomological Supplies

WARD'S NATURAL SCIENCEESTABLISHMENT

84-102 College Ave. Rochester, N. Y.

THE SCIENTIFIC MONTHLYAn illustrated magazine, devoted to the dif-

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Annual Subscription, $S5.oo.Single number, 5O cents.

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S.OO a Year I5 Cents a Copy

THE SCIENCE PRESSGrand Central Terminal, New York City

By means of sliding-contacts the resistance value of

JAGABI RHEOSTATSean be varied from zero to full rating in exceedinglysmaitll steps.'1'hey are eminently suited for, and are largely usedIn Educational, Research and Industrial Laboratories.

Write for ilustrated BuUetin 1140-BJAMES G. BIDDLE, PHILADELPHIA

1211-13 ARCH STREET

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