APPARATUS AND METHODS. 



of the plate receives the light. An excellent "photophore" 

 or simple dissecting microscope can be made in this way, 

 the rod carrying the lens being fixe'd to one side of the 

 frame. 



4. Dissecting Micro- 

 scope. This extremely 

 useful instrument ( Fig. 

 4) consists of a stand 

 mounted on a heavy metal 

 base and carrying (1) a 

 glass plate or stage for 

 the object to be examined, 

 (2) a lens carrier in which 

 the lens can be raised or 

 lowered by a rack-and- 

 pinion adjustment, ( 3 ) 

 an illuminator below the 

 stage with a mirror on 

 one side and a white 

 plate on the other, (4) 



arm-pieces which can be attached on each side of the stage 

 to serve as rests for the hands when teasing out tissues or 

 otherwise manipulating the specimen examined. The form 

 shown in Fig. 5 is much cheaper. 



Fig. 4. Dissecting Microscope. 



Fig. 5. Cheap form of Dissecting Microscope. 



5. Compound Microscope. The simple microscope 

 can be used for all purposes where a magnification of not 

 more than 20 diameters is required, and is an extremely 



