MANUFACTURERS OF TV jT 
The Leading American MICROSCOPE 
OBJECTIVES AND ACCESSORIES. 
Photographic Lenses, and other Optical Instruments. 
— mwsQTtiam 
NEW PETROGRAPHICAL MICROSCOPE, 
Constructed by advice and assistance of Prof. Georgk H. Williams, 
Johns Hopkins University. 
Complete Illustrated Catalogue on Application , 
Factory and Main Office: 
53*-543 North St. Paul Street, 
ROCHESTER, N. Y. 
Branch Office: 
48 and 50 Maiden Lane, 
NEW YORK. 
