14 



STUDENTS HISTOLOGY 



piece of tissue is then carefully wiped dry with the blotting-paper, 

 and, just as the imbedding begins to congeal around the edges, is 

 pressed below the surface with a needle and held until the cool 

 mixture fixes it in position. The whole is now allowed to become 

 thoroughly cold. By turning the screw the plug of wax is raised; 



FIG. 7. METHOD OF CUTTING SECTIONS WITH THE STIRLING MICROTOME. 



and it must be gradually cut away, by sliding the knife across the 

 plate, until the upper part of the tissue appears. 



Before commencing to cut sections however the tissue may 

 have been imbedded provide yourself with a saucer of alcohol and 

 a camel's -hair pencil. Having wet the knife, turn the screw so 

 that the tissue, with its imbedding, appears slightly above the 



FIG. 8. THOMA MICROTOME. 



plate of the microtome, and then, resting the blade of the razor on 

 the plate (vide Fig. 7), make the cut precisely as in free-hand 

 cutting. The section is then brushed off into the saucer, the 

 screw turned up slightly, the razor wet, and a second cut made. 

 These steps are repeated until the required number of sections has 

 been obtained. 



