SECTION CUTTING WITH THE MICROTOME 



15 



The imbedding material will separate from the cuts as they 

 are floated in the alcohol. They may now be selected, lifted 

 with the needle into clean spirit, and preserved, as before indi- 

 cated, for future operations.- 



The finest section cutting can only be done with one of the 

 more elaborate and expensive microtomes (Figs. 8 and 9). Each 

 of these instruments consists of a heavy sliding knife -carrier, 

 which moves on a level and with great precision, and of a device 



FIG. 9. SCHANZE MICROTOME. 



(screw or inclined plane) for elevating the object that is cut the 

 desired distance after each excursion of the knife. The distance 

 that the object is raised is, of course, the thickness of the sec- 

 tion. Such microtomes are especially adapted to cutting frozen 

 tissues or those imbedded in celloidin, but they may be used with 

 paraffin imbedding. The Minot microtome, which is intended for 

 cutting objects in paraffin, is preferable for the latter purpose, 

 especially if a number of sections are to be kept in the order in 

 which they were cut, "serial sections." 



