I-' 



SCIENCE 



NlW SEBIKS TrT>TT>A-W A TTriTTOT 99 1 Q 1 ^^ SINGLE COPIES, 15 CT8. 



Vol. XXXVIII. No. 973 J? BID AY, AUGUST ZZ, Xy Id Annual Subbobiption, 85.00 



Bausch & Lomb Optica! Co. 

 Carl Zeiss Works^ Jena 



'~|~*HE close identity of the two leading optical houses of America 

 and Europe is unique in its conception and operation. It 

 has for its aim joint scientific achievement — the interchange of 

 ideas, suggested improvements and individual productive efforts in 

 which each firm enjoys the benefit of the other's progress. 



This close relation applies in the fullest sense to the Micro- 

 scope, Projection, Telescope, Range Finder, Photographic Lens and 

 Field Glass departments — in fact, to every line of our activity. 

 The results thus far show gratifying advances, in both optical and 

 mechanical attainment, and the future promises a still higher 

 accomplishment. 



If further interested, write for our booklet describing this 

 alliance and the separate enterprises. 



Bausch ^]pmb Optical (o. 



409 ST. PAUL STREET ROCHESTER, N.'V; 



NEW YORK WASHINGTON CHICAGO SAN FRANCUCO 



