CUTTING AND MOUNTING SECTIONS. 299 



in strong alcohol and allow it to remain until it is hard 

 enough to cut, changing the alcohol if necessary. 



When ready to cut, place the corner of the glass slide over 

 the well of the microtome, with the object hanging in the 

 well, and fill the well even to the surface with the paraffine 

 embedding mass. As soon as the paraffine hardens, the glass 

 slide can be easily removed with a sliding motion which 

 leaves the surface to be cut parallel to the surface of the 

 microtome. 



Cut away the embedding mass of paraffine in such a man- 

 ner that the front and back sides shall be parallel and leave 

 enough to support the object to be cut, and then slice with 

 a razor or the knife of the microtome. The parallel edge 

 of the first section adheres to the edge of the succeeding 

 section, and the series of sections can be removed from the 

 knife, placed in order on the slide, and secured in position. 

 The superfluous paraffiue can be removed with warm tur- 

 pentine, and the turpentine with alcohol if it is desirable 

 to stain the sections on the slide. 



If the piece to be sectioned is large, after treating with 

 the solution of celloidin it can be embedded in a small 

 folded paper box, as directed for embedding in paraffine. 



As both absolute alcohol and oil of cloves dissolve the 

 celloidin, in dehydrating use alcohol of 96 per cent, and in 

 clearing oil of bergamot, oil of sandal, or oil of origanum.* 



Dr. L. Lowe's mixture for embedding is the following: 



Gelatine 1 part. 



Glycerine 1 part. 



Water 5 parts. 



This is put upon the water-bath and thoroughly dissolved 

 and afterwards strained. After coloring the animal prep- 

 aration it is well washed with water and then submerged 

 in the gelatine at a temperature of not more than 122 F. 



* Contributed by N. N. Mason, Esq. 



