FUNDAMENTAL CONSIDERATIONS 



Sliding Microtome. This type of microtome (see Fig. 9) is adapted 

 for cutting all kinds of sections. It consists of an iron supporting 

 fame of horizontal and upright portions. The horizontal base rests 

 on the table and is hollowed out to accommodate a drip pan that 

 can readily be removed and cleaned. 



The front of the upright portion exhibits a frame which accomo- 

 dates a sliding feed mechanism to which is attached the object 



carrier. The top of the upright portion 

 shows a V shaped bed which carries a 

 solid iron block which can be readily 

 slid along the bed when the latter is 

 lubricated with paraffin oil. The upper 

 surface of the block is grooved to ac- 

 comodate the thumb screw. The 

 microtome knife consists of a blade 



a.. 



FIG. 8. Hand microtome. PIG. 9. A sliding microtome. Blade (a) ; lever 

 Description in text. (6). (From McJunkin.) 



portion, that is flat on its lower and hollow ground on its upper 

 face, and a forked handle. The latter is slid into the stem of^the 

 thumb screw which has . previously been slid into the groove of 

 the block and its position adjusted. Sections of woody material 

 can be cut directly on this microtome and placed in dilute alcohol. 

 When paraffine sections are cut, the cutting edge of the knife 

 should be parallel to the motion but when celloidin sections are 

 desired the knife must be set at an oblique angle to the frame 

 and drawn across the block with a long sliding motion. The knife 



