LESSON VI. 



STAINING AND MOUNTING SECTIONS 

 IMBEDDED IN PARAFFIN. 



1. Dissolving paraffin from sections free in 

 fluid 1 , a. Place a section in a watch-glass, and pour 

 over it a few drops of turpentine. See that the balsam 

 and a clean cover-slip are ready. With a lifter transfer 

 the section to a slide, tilt the slide and wipe away the 

 excess of turpentine, then add a drop of balsam, and 

 cover with a cover-slip. 



b. Mount another section, using xylol instead of turpentine. 

 Xylol 2 is very volatile, and the section after removal of excess 

 of xylol will rapidly dry on the slide and become useless unless 

 this is prevented by the addition of balsam. Xylol is preferable 

 to turpentine for tissues that have been treated with osmic acid, 



1 A compact or fairly compact structure should be taken, as a 

 piece of liver, pancreas, ureter or bladder, hardened in potassium 

 bichromate. The piece should be stained with heemalum for a day 

 before imbedding, for 1, and left unstained for 2. 



2 Benzol, toluol, and a mixture of four parts of turpentine with one 

 part of creosote, are also used to dissolve paraffin. 



