SCIENCE 



SK\r Series 

 Ttou L, No. 1303 



TTuTT-liV l~)TJ'riirAT-RTi'-D 1Q 1Q1Q AkNCAL SUBSCEIPTION, 85.00 



ritlDAY, lJl<.LiLM.iiiLli 1», 1»1W After January 1, 1920, 86.00 



BALOPTICON 



The Quality Shows on the Screen 



TNSTANTLY — the perfect picture ! Perfect in focus ; 

 perfect in photographic quahty; perfect in illumination. 

 Bausch & Lomb Balopticons are therefore, perfect projec- 

 tors — perfect means for visual education and entertainment. 



Writ* for Catalog 



Bausch & Lomb Optical Co. 



522 St. Paul Street ROCHESTER, N. Y 



Combined Balopticon f< 

 Lantern Slides and Opaqu< 

 Objects, Price $150.00. 



B^^schWl^ 



