STAINING, PRACTICAL AND THEORETICAL 



GLYCERIN JELLY 



Refractive index i'4i4 



This is a very old mounting medium, first used nearly a century 

 ago, and still used to some extent today for fat preparations, 

 frozen sections, gelatine sections, and whole mounts. However, 

 Dade (i960) states that glycerin jelly is not a good medium for 

 " fluid " mounts; that its refractive index is too low, and that it 

 has no advantages over glycerin or lactophenol which he favours 

 for " fluid " mounts. 



For frozen sections of fat preparations, the more modern 

 medium, Aquamount, is to be preferred, as, unlike glycerin jelly, 

 this is a liquid which sets hard. Moreover, glycerin jelly has to 

 be melted before it can be applied. 



Preparations mounted in glycerin jelly may be preserved for 

 some time by painting the edges of the coverslips with molten 

 glycerin jelly, and when this has set, two coats of Laktoseal should 

 be applied with a fine, soft brush, allowing the first coat to dry 

 thoroughly (a few minutes) before the second coat is applied. 

 Gatenby & Beams (1950) state that gold size may be used for 

 sealing glycerin jelly mounts on slides. However, it would appear 

 that Laktoseal is preferable on account of the rapidity with which 

 it dries and seals. 



GLYCHROGEL MOUNTANT 



For gelatine sections, teased preparations, nematodes etc. 



A. Chrome alum . , . . . . 0-2 gm. 

 Distilled water 30 ml. 



Dissolve by warming. 



B. Gelatine granules . . . , • • 3 gm. 

 Distilled water . . . . • • 50 ml. 

 Glycerine . . . . . . . . 20 ml. 



Warm the water to 45° C. then shake in the gelatine a little 

 at a time until dissolved and add the glycerine. 



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