THE METHODS OF MOUNTING MICROBES 91 



(3) Clearing agents, . 



Oil of cloves. 

 Oil of cedar. 

 Xylol. 



Aniline oil. 



Terebene. 

 ( Canada balsam. 



(4) Mounting agents, . . . \ Dammar varnish. 



I Glycerine. 

 f Hollis' glue. 



3 , Cementing agent,, 



iBlack asphalte varnish. 



To mount afresh specimen, the section should be 

 placed with the utmost care in the centre of a glass 

 slide. The section should not be folded in any part, 

 therefore it must be carefully spread out with 

 needles. This must be performed without stretch- 

 ing the specimen. After this has been done, wipe 

 off all moisture with a clean cloth. Now take up 

 ' a cover-glass and place a drop of glycerine in the 

 centre, invert and place it horizontally on the pre- 

 paration, leaving the weight of the cover-glass to 

 spread out the glycerine.' If there is an excess of 

 glycerine round the edges of the cover- glass, it 

 must be carefully absorbed by filter or blotting- 

 paper, but on no account should the cover-glass be 

 removed. To seal, ring, or cement the preparation, 

 paint round the edge of the cover-glass and a little 

 way on the slide, a ring of Hollis' glue or Dammar 

 varnish. Hollis' glue 1 is better than Dammar 

 varnish, for it is not acted upon by the cedar oil 

 used with oil-immersion lenses. The sealing of 



1 Gold size is sometimes used for sealing glycerine prepara- 

 tions. 



