SCIENCE 



Ne"W Sbeies 



Vol. LVI, No. I-ISS 



Friday, July 21, 1922 



AffNtTAL Subscription, $6.00 

 Single Copies, 15 Cts. 



Bausch & Lomb 



Photomicrographic 

 Equipment 



O AUSCH & LOMB have always been 

 -"-' among the leaders in the develop- 

 ment of photomicrographic equipment. 

 We are today the only American makers 

 of a complete line of this apparatus, con- 

 sisting of outfits ranging from simple 

 cameras for use with ordinary micro- 

 scopes, to the large GSA-IL9 outfit shown 

 above. 



Wherever a microscope is required, a 

 photomicrographic camera can be used to 

 advantage for making a permanent, photo- 

 graphic record of the image. In industrial 

 laboratories, for testing and inspecting, 

 and in hospital and university labora- 

 tories, for educational and research pur- 

 poses, our equipment is widely used. 



The manufacture of this apparatus in- 

 volves the very finest work in optics, 

 combined with mechanical construction of great precision. Our many years of experience in 

 making optical instruments has enabled us to meet these requirements in the fullest measure. 



Writa for descriptive circulars and let us know of your needs. 



Bausch & Lomb Optical Company 



409 St. Paul Street, Rochester, N. Y. 



New York 



Washington 



Chicago 



San Francisco 



London 



Leading American Makers of Optical Measuring Instruments, Photomicrographic Apparatus, Photographic 



Lenses, Microscopes, Projection Apparatus (Balopticons), Ophthalmic Lenses and Instruments, 



Range Finders and Gun-Sights for Army and Navy, Searchhght Reflectors, Stereo-Prism 



Binoculars, Telescopes, Magnifiers, Auto-nobile Lenses and other High-Grode 



Optical Products. 



