NEw SERIES SINGLE Copigs, 15 Ors. 
VoL. XXXY. No. 913 FRIpAy, JUNE 28, 1912 ANNUAL SUBSCRIPTION, $5.00 
Model D Balopticon with 19]4-inch optical bed-$67.50 
The Ideal Lantern 
for the Physical Laboratory 
_ This lantern is ideal for the physical laboratory because of its 
rigidity and high-grade equipment. 
The accurately milled optical bed and the clamping blocks for the 
supports carrying accessories assure absolute alignment. The 
ode 
eee Insti 
JUN 23 1912, 
Ayr 
Stiona| | 
od ¥ a e 
Balopticon 
is fitted with triple condensing system, permitting use of parallel, 
convergent or divergent light. 
All attachments such as projection microscope, polariscope, opaque 
attachment, etc., may be added as desired. 
The Superior Quality 
of BauschGLomb len- 
ses, microscopes, field DESCRIPTIVE CIRCULAR 15D SENT ON REQUEST 
glasses, projection ap- 
paratus, engineering f~o? 7 ima oe @ 
mdeterscnte| BOAUusch £4 lomb Optical ©. 
struments is the pro- F 
duct of nearly Sixty NEW YORK WASHINGTON CHICAGO SAN FRANCISCO 
Year’s Experience. LONDON ROCHESTER. NY. FRANKFORT 
Extra supports and accessory bed may be secured 
