SCIENCE—ADV ERTISEMENTS 
WANTED 
As editor for scientific publications from re- 
search laboratory, woman graduate with 
knowledge of physics and chemistry. Per- 
manent position offering good field to 
student of science having literary tastes. 
Apply to the 
Director, Research Laboratory 
Eastman Kodak Company 
ROCHESTER, N. Y. 
Prof. F. A. Saunder’s Wave Projec= 
tion Slide 
e 
The Microscope 
12th Edition, Published April 10, 1917 
Re-Writtenm and largely Re-Illustrated 
By SIMON HENRY GAGE of Cornell Univeraity 
Postpaid $3.00 
COMSTOCK PUBLISHING CO., Ithaca, N. Y. 
Memoirs of the Wistar Institute of Anatomy and 
Biology. No. 6, 1915 
THE RAT 
Data and Reference Tables. 
278 Pages. 89 Tables. 
Bibliography. 
Compiled and Edited by HENRY H. DONALDSON. 
Postpaid, $3.00. 
The Wistar Institute Philadelphia, Pa. 
WHITE MICE FOR SALE 
All ages. Immediate shipment. 
Standing orders solicited 
The Laboratory Animal Supply Co. 
Croton Lake, N. Y. 
MARINE BIOLOGICAL LABORATORY 
WOODS HOLE, MASS. 
Haale Lea Material 
Zoolory. reserved material of all types of animals 
or ‘class nee and for the museum. Ba 
2. Embryology. Stages of some invertebrates, fishes (in- 
eluding Acanthias, Amia and Lepidosteus), Amphibia, and 
s0me mammals, 
3. Botany. Preserved material of Algae, Fungi, Liver- 
worts and Mosses. Price lists furnished on a pelieatton. to 
GEORGE M. GRAY, Curator, Woods Hele, Mass. 
Precision Measuring In- 
struments of great variety Beas 365 180" No. 
5345-5349 Lake Park Ave. 
SCIENTIFIC LECTURER WANTED 
The museum wishes to employ a resident, male lecturer to 
assist in the work of its education department with schools and 
general public. 
Requirements: good foundation in biologic and geologic 
subjects, lecturing ability, tee voice and presence. 
Salary, $1,600 to $1,8 
perience. Address 
DIRECTOR, PUBLIC MUSEUM 
MILWAUKEE, WIS. 
The New Science of the Fundamental Physics 
y W. W. STRONG, Ph. 
Includes ehuntees on the Goal of tne New Physics, 
the Directed Elements, the Atomic Systems and 
Models, Disintegration and Radiation Theories, 
Elementarquanta, the Fundamental Units and Rel- 
ativity. 117 p. cloth. $1.25. 
S. I.E. M. CO., Mechanicsburg, Pa. 
0, according to abilities and ex- 
Wm. Gaertner & Co. [ 
Standard Apparatus of 
New and Improved 
Designs 
Roce Device for Ther- 
Chicago 
The L. & N. 
High Sensitivity Galvanometer 
An instrument 
of extremely 
high sensitivity, 
yet. one with 
which itisa 
leasure to work 
ecause it is very 
easily set up and 
its working char- 
acteristics are all 
that could be de- 
sired. 
If you have 
any research 
work involving 
- the use of a gal- 
vanometer of high sensitivity this instrument 
can be built to your order, giving you the 
maximum sensitivity under your working con- 
ditions. 
We solicit correspondence from those who are look- 
ing for an out-of-the-ordinary galvuanometer 
THE LEEDS & NORTHRUP CO. « 
4921 Stenton Avenue PHILADELPHIA 
