60 PRACTICAL HISTOLOGY [VII 



in small pieces is added in excess to the chloroform ; in half-an-hour 

 the bottle is placed at the melting point of the paraffin, when the 

 paraffin has dissolved, the whole is transferred to an open vessel, 

 more paraffin being added, and warmed for \ to 1 hour ; the tissue 

 is then removed to fresh paraffin, and left for \ to 1 hour. Chloroform 

 if not driven off, makes the paraffin too soft to cut. 



Paraffin cuts less well when mixed with a clearing agent, so that 

 after the tissue has soaked in paraffin for a short time, it may be 

 advisable to transfer it to fresh paraffin. 



