MOUNTING MEDIA. 



When sections are mounted with Balsam, Dammar, Far- 

 rant, Glycerine and Q-um, or Glycerine Jelly, it is not a neces- 

 sity that the cover-glasses should be fixed with cement, as 

 these fluids solidify at the edges, and so fix the cover-glass. 



Some cement (Caoutchouc by preference) must be employed 

 when Glycerine or aqueous solutions are to be used. 



CANADA BALSAM. 



A soft substance which is usually dried over a water-bath 

 until, when cooled, it is brittle. It is then dissolved in Benzol 

 or Xylol to form a somewhat thin solution ; about 200 grms. 

 of Balsam to 100 cc. of Benzol : the Xylol solution may be 

 rather thicker, as it evaporates more slowly. Neither of them 

 will affect the Aniline stains. 



Mounts in Benzol Balsam harden in a day or two ; those 

 in Xylol Balsam remain soft for a week or two. I there- 

 fore much prefer to mount in Benzol Balsam. 



Transfer the sections to a slide (using for thin sections a 

 glass rod, p. 19), remove excess of clearing agent by gently 

 pressing on the section with clean blotting-paper, add one or 

 wo drops of Balsam Solution, and apply the cover-glass. 



DAMMAR SOLUTION. 



Gum Dammar dissolved in Benzol or Xylol. 

 About 100 grms. of Dammar to 100 cc. of Benzol. 



