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In every laboratory where electricity is used, there is need for variable resistances-and to meet such requirements we offer a well tried series of

"JAGABI" SLIDING CONTACT

TUBE RHEOSTATS

Hundreds of them have been sold during the past three years, to various Government Departments, Universities, Colleges, Technical Schools, Industrial Companies, etc.-—and have "made good" under every-day service conditions.

WRITE FOR ILLUSTRATED DESCRIPTIVE BULLETIN 987

JAMES G. BIDDLE

1211-13 ARCH STREET, PHILADELPHIA

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Not

How Much You Burn

but

How Much is Wasted

With fuel bills and freight bills such a large item in operating costs, small plants are finding it worth while to save from 10% to 25% by burning their fuel more efficiently.

Firemen working from the charts of the Hays Automatic CO2 and Draft Recorder know all the conditions conducive to efficient combustion. They know the correct draft, thickness of fuel bed, how to intelligently control the dampers, everything necessary to maintain the highest possible percentage of CO2. Naturally they work for high records, which mean additional savings for you.

Complete description of the advantages to be gained in your plant I will be sent on request.

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Awarded certificate of merit by the Franklin Institute

We carry a complete line of Hays Combustion Efficiency Appliances

BRAUN-KNECHT-HEIMANN-CO.

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The Silverman Illuminator

A new eye for the microscope

Offers important advantages for practically every application of the Microscope

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a-It shows more detail.

A clearer and better defined picture is presented to the eye and the camera. WOH

c-Several novel methods of illumination can be produced.

d-It saves very much valuable time.

-It prevents eye strain, eye fatigue, and brain fag.

f-It can be lowered in to deep, hollow places.

g-It gives excellent results for very low power work as well as higher magnifi

cations, also in oil immersion work.

k-It can be used with any Microscope, ordinary or binocular.

A small circular tube lamp surrounds the objective and furnishes a diffused and uniform illumination directly where it is needed. The Silverman Illuminator marks

A Great Advance in Microscope Illumination

For sale by all the better dealers

Ludwig Hommel & Co.

Write for

Bulletin 45-B

530-534 Fernando St,

PITTSBURGH, PA.

A NEW WILEY BOOK-READY MAY 1st.

A FRENCH-ENGLISH DICTIONARY

FOR CHEMISTS

By AUSTIN M. PATTERSON, Ph. D.

Formerly Editor of "Chemical Abstracts"

Author of "A GERMAN-ENGLISH DICTIONARY FOR CHEMISTS"

This useful new Dictionary defines over 30,000 words and phrases. It is the only book covering its particular field, and follows the lines of the same author's very successful German-English Dictionary. The entire chemical field is covered, and in addition common general words and many troublesome idioms and verb forms are included.

The Introduction contains information on French chemical nomenclature and gives a few principles of grammar and examples of the plurals of nouns, declension of verbs, ete. This book has 384 pages, 5 by 7, and is flexibly bound. $3.00 postpaid.

Let us send YOU a Free Examination copy-
determine for yourself just how valuable it is

JOHN WILEY & SONS, Inc.

432 Fourth Avenue

NEW YORK

NEW SERIES

VOL. LIII, No. 1374

FRIDAY, APRIL 29, 199*

SINGLE COPIES, 15 CTS.
ANNUAL SUBSCRIPTION, $6.00

RECENTLY ISSUED

Leland Stanford, Jr., Univ.,

Stanford Univ.,

Guido H. Marx,

Calif

Smith's Bacterial Diseases

Plants

irst treatise
ills a need

"There are many unique features about this book.
of its kind, a product of the author's own researches,
that was rapidly becoming urgent. Its author is an au
n the sub-
ject. The style is easy and tremendously interesting."
ggestions
given throughout are practicable-they have been thorougnly tried-and
the hints on the details of technic will prove serviceable. The book is
adaptable to the use of either the graduate or the undergraduate student."
-L. R. Hesler in "Phytopathology."

By ERWIN F. SMITH, in charge of Laboratory of Plant Pathology, Bureau of Plant Industry, Washington,
D. C. Octavo of 600 pages, illustrated.
Cloth, $10.00 net.

Prentiss and Arey's Embryology

Third
Edition

This edition has been given a thorough and careful revision, adding every
new advancement. It deals particularly with the chick and pig embryos
usually studied in the laboratory, comparing them constantly with the
human embryo and giving you a concise, systematic account of human
embryology. A large number of original dissections are described and
illustrated.

Large octavo of 411 pages, with 388 illustrations B CHARLES W. PRENTISS, Ph.D., formerly Professor of
Microscopic Anatomy, and LESLIE B. AREY, Ph.D., Associate Professor of Anatomy, Northwestern University.
Cloth, $5.50 net.

Mallory and Wright's Pathologic Technic

Seventh
Edition

This work gives the technic of bacteriologic methods, bacteriology of
various diseases, histologic methods, the special methods used in clinical
bacteriology and pathology, and the preparation of bacterial vaccines.
Octavo of 555 pages, with 181 illustrations. By FRANK BURR MALLORY, M.D., Pathologist to the Boston City
Hospital; and JAMES HOMER WRIGHT, M.D., Pathologist to the Massachusetts General Hospital.
Cloth, $4.75 net.

Sign and Mail this Order Form Today

W. B. SAUNDERS COMPANY, West Washington Sq., Phila. Please send me the books marked (X), charging the amount to my account:

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