BULLOCK'S FIRST-CLASS MICROSCOPE A 1. 63 



avoided. The iris diaphragm has the society screw so 

 that any objective can be used for a condenser, or it 

 'can be used above the objective as an adapter, to reduce 

 the light in the instrument. The stand is nineteen 

 Inches high when arranged for use. 



This stand and the " Centennial " of Mr. Zentmayer, 

 may be considered as rival instruments, and neither of 

 them enters the list for a slow race ; both are respec- 

 tively the masterpieces of their makers, and are claimed 

 to be the very embodiment of all and singular that can 

 be desired by the microscopist. 



Purely in the interest of the reader, we proceed to 

 compare these stands with each other ; the final verdict 

 shall be left a matter of individual election. 



First. The price of both instruments is precisely the 

 -same, while the Bulloch has additional the iris dia- 

 phragm, the mechanical stage with its adaptations for 



