THE MICROSCOPE 



515 



For the sake of emphasis it may be said that the microscopist works, 

 with his right hand upon the fine adjustment and his left hand upon the 



Eye-piece (Ocular) 



Tube 



Triple revolver 

 Objective 



Draw-tube 



Back and pinion adjustment 



Micrometer Screw 



FIG. 493 



slide. As the latter is moved about, bringing different fields into view, 

 the focussing is done with the adjustment and not with the eyes. It is- 

 impossible to study even a single field without constantly changing the 



