2Q8 



PRACTICAL MICROSCOPY. 



MOUNTED BY 



GEORGE E, DAVIS 



Boiler 



Incrustation. 

 (Section.") 



hot plate, gently press down the cover, keep on the 



hot plate for a short time and take away to a cool 



place to set. 



No more balsam should be used than sufficient to reach 

 to the edges of the glass cover, and if this 

 point be carefully attended to, the slip will 

 require no cleaning preparatory to covering 

 with paper. 



The covers used and recommended by 

 the author may be seen as annexed. 



These covers should be cut about ^ of 

 an inch less than the slide they are intended 

 to cover, leaving the edges of the glass ex- 

 posed; there is no use in binding up the 

 glass in paper, it only helps to absorb 

 moisture, and in the case of many objects 

 mounted dry, serves to encourage the 

 growth of mildew. 



When mounting in pure balsam, espe- 

 cially if old, the slide gets very hot, so 



that the American clip shown in Fig. 242 is a convenient 



article. 



Catalogue No. 611. 

 Date 10/3/80. 



Medium 

 Balsam. 



Cell 



FIG. 242. 



It has already been shown under the head of dry 

 mounting how diatoms are distributed over the surface 

 of a thin cover. They may also be mounted in balsam. 



On the centre of the glass slip place a tiny drop of old 

 balsam, and with a pair of tweezers place the cover-glass 



