1 84 



PRACTICAL MICROSCOPY. 



limited in their application. They may be necessary at 

 times, when it is desired to make a hurried examination ; 



but the student is certainly 

 advised never to make 

 hurried examinations. 



We now come to the 

 second division, where sec- 

 tions are cut in the micro- 

 tome, of which there are 

 several forms, constructed in 

 accordance with the require- 

 ments of the originators. 

 The most common form of section-cutter is shown in 

 Fig. 172. It is generally used for cutting sections of wood, 

 stems, and other semi-hard substances. The substance to 



FIG. 171. 



FIG. 172. 



FIG. 173. 



be cut is kept firmly in position by means of the side screw, 

 and the quantity necessary for each section sent up by the 

 screw below. 



Another section-cutting machine used for the same 



