38 



MICROSCOPICAL RESEARCH 



The smears left by this operation may be removed with a soft 

 cloth moistened with 92 per cent, alcohol. The superfluous jelly, on 

 glycerine jelly mounts, may be removed by washing the slide in cold 

 water with a stiff tooth brush. The slide should now be placed on 

 the turntable and the preparation sealed up with a brown cement 

 ring, as already described. When the brown cement is dry, a ring of 

 zinc oxide may be applied, and on the top of this a finishing ring of 

 asphaltum, or a single black finishing ring may be applied over the 

 brown cement one; the slide should now be labelled and named for use. 



Fig. 25. — Slides in various stages of cleaning and ringing, i. Before hot-knifing. 2. First 

 ring of brown cement. 3. Finished with zinc oxide and asphaltum. 4. Oval 

 mount, finished same as number 3. 



