30 THE MICROSCOPE 



« 

 Glycerine. — Pure Glycerine may be used, or a mixture of 

 equal parts of glycerine and water, which is somewhat preferable. 

 For quick mounting, for specimens which are unstained or hyaline 

 in character, and for those which require testing, itj_is better than 

 Canada Balsam. A section-lifter is required in handling speci- 

 mens, and great care should be taken in removing them from spirit 

 to water, the surface-currents causing rapid movements which may 

 lead to the breaking-up of a section. The time during which they 

 should remain in water before removal to glycerine depends upon 

 their size and density, from five to ten minutes being generally 

 sufficient. 



In the preparation and mounting of many things from the 

 vegetable kingdom, as mosses, algae, cuticles, sections, etc. ; or 

 from the animal kingdom, as eyes and wings of insects, gastric 

 teeth, palates of the mollusca, it is only necessary, if they are suffi- 

 ciently clean and not too dark in colour, to put them for a few 

 hours into a mixture of methylated spirit, glycerine, and water 

 (about equal parts of each),* although exactness is not necessary, as 

 the mixture may be varied to suit circumstances. When they are 

 taken from this mixture, they must be placed upon the centre of 

 the slide, and the surplus liquid absorbed by blotting-paper, and 

 sufficient pure glycerine added to thoroughly fill the cell. The 

 cover-glass should now be made quite moist by breathing upon it, 

 and carefully lowered down on to the object, and secured by the 

 spring clips. 



Or, instead of pure Glycerine, Glycerine-Jelly may be used^ 

 when either of two plans may be followed. Glycerine-Jelly may 

 be liquified by placing the bottle in hot water, and then 

 dropping the liquid jelly upon the slide, or, as is frequently 

 preferred, a small piece may be cut from the bottle, and put upon 

 the object, and the slide gently warmed, when the jelly will diffuse 

 itself through the object, which will be found exceptionally free 



* A very excellent mixture is that known as Hantsch's fluid, and is com- 

 posed of — 



Alcohol ... ... ... •••3 parts. 



Water ... ... ... ... 2 parts. 



Glycerine ... ... ... ... i part. 



This fluid will also be found most suitable in which to keep all kinds of insects 

 preparatory to mounting. — Ed, 



