SCIENCE 



Nirw 9BBIES 

 Vol. L, No. 1299 



Friday, November 21, 1919 



Annual Sdbscbiption, 85.00 

 After January 1, 1920, 86.00 



BAUSCH & LOME OPTICAL COMPANY 

 Rochester, N. Y. 



New York Washington Chicago San Francisco London 



Makers of Ophthalmic Lenses and Instruments, Microscopes, Photographic Lenses, Balopticons, 

 Binoculars,'^ Magnifiers, Readers and other High-Grade Optical Products 



