76 Modern Microscopy. 



Soak the specimen in ether for an hour or two, then 

 transfer it to the solution of celloidin, and let it remain for 

 twelve hours, or until required. 



Take the specimen from the celloidin on the point of a 

 needle, and hold it exposed to the air until the celloidin 

 around the tissue has set ; then push it off the needle into 

 equal parts of methylated spirit and water, in which it 

 should remain for an hour or two to complete the harden- 

 ing. Then embed in carrot, and make the sections in an 



FIG. 30. Booking Microtome. 



ordinary microtome, or the specimen may be soaked in gum 

 and the sections made with a freezing microtome. 



If it be desired to remove the celloidin from the sections, 

 soak them in ether, and then transfer to methylated spirit, 

 then into water, and finally into the staining solution ; 

 but specimens that are infiltrated with celloidin are usually 

 stained in bulk before they are infiltrated, and after the 

 sections are cut they are dehydrated in methylated spirit, 

 cleared in oil of lavender or bergamot, and mounted in 

 Canada balsam. 



