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 this magazine! place a 1 cent stamp on this notice* 

 mail the magazine, and It will be placed in the 

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SCIENCE 





New Sesiks 



Vol. XUX, No. 1265 



Friday, March 28, 1919 



SiKOLB Copies, 15 Crs. 

 AmnjAL SuBscBipnoH, S5.00 



Combined Balopticon — For Lanlern Slides and^ 

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Leading American Makers of Photographic Lenses, Microscopes, Projection Apparatus (Batopli- 



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