98 METHODS OF MICROSCOPICAL EESEARCH. 



remove celloidin. It must be remembered that oil 

 of cloves renders specimens which have been 

 allowed to remain in it very brittle. 



Oil of Bergamot is a valuable, though costly 

 agent ; it clears the celloidin embedded specimens 

 and does not affect anilin stains to any great extent. 

 It is fairly rapid in its action and clears well. 



Cedar Wood Oil. This oil is not expensive, 

 but is very slow in its action, it also has the valuable 

 properties of clearing perfectly, however slowly, 

 and of not injuriously affecting anilin dye's, or of 

 shrinking specimens which have been hardened or 

 preserved in alcohol. It is very useful for clearing 

 vegetable sections, though extremely slow in doing 

 so, and celloidin sections may be cleared in it, but it 

 takes several hours to render them transparent. 



Mounting Media and Cements. 



Many media in which specimens may be examined 

 and delicate dissections made for examination, are 

 not in the true sense of the term preservative and 

 therefore serve only a temporary purpose. Many 

 solutions again which re-act upon tissues, and 

 elucidate their features and composition serve only, 

 in like manner, for purposes of temporary examina- 

 tion and study. It is intended, in the following list 

 of media in which specimens and sections can be 

 mounted, to give the formulae and methods of using 

 and applying the best preservative media so as to 

 secure the permanence and safety of the prepara- 

 tions which are made with them. The list will be 

 supplemented with formulae for the most useful 

 fluids in which to make dissections and to place 



