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mail the magazine, and it will be placedin the 
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SCIENCE 
N SERins £ SINGLE CoPIEs, 15 Ors. 
= XLVUI No. 1247 Fripay, NOVEMBER 22, 1918 ANNUAL SUBSCRIPTION, $5.00 
Bausch" lomb 
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Microscope FS2 
Because of the demands made upon our resources for some 
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While proud to be of service in this world crisis, we shall 
expect to serve our other patrons even more efficiently than 
before, when the world is again at peace. 
Bausch £7 lomb Optical ©. 
409 ST. PAUL STREET ROCHESTER, N.Y. 
New York Washington Chicago San Francisco 
Leading American Makers of Microscopes, Projection Apparatus, (Balopticons), Photographic 
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