SPECIFIC STAINS. 45 



tissue and cartilage, cancerous growths, and the eye ; it also 

 hardens tissue. 



The tissue must he fresh and the sections very thin. They 

 are first washed in Distilled Water to remove the Chlorides, 

 and are then placed in the Silver solution for half an hour 

 in the dark. After this they are washed in Distilled Water, 

 placed in ordinary Water, and exposed to diffuse light till 

 brown ; they must he mounted in Glycerine or Glycerine Jelly, 

 and kept in the dark. 



' ' Fixing " with Hyposulphite of Sodium has been suggested, 

 to render the specimens permanent in light. 



VICTORIA BLUE. 



Victoria Blue, 0'25 grm. ; Eectified Spirit, 20 cc. ; Distilled 

 Water, 80 cc. 



Stain the sections 3 to 5 minutes, rinse in Distilled Water 

 about 2 minutes, wash in 90 p. c. Alcohol 3 or 4 minutes, 

 dehydrate in Absolute Alcohol 3 or 4 minutes, clear in Cedar 

 Oil, and mount in Balsam. 



This is especially useful for demonstrating elastic tissue, 

 staining the elastic fibres an intense blue ; it is, however, 

 somewhat readily extracted by Alcohol. 



It stains best after hardening in Chromium Salts, but this 

 is not necessary. It also acts as a nuclear stain. 



DAHLIA VIOLET. 



Dahlia Yiolet, 2 grms. ; Eectified Spirit, 25 cc. ; Distilled 

 Water, 70 cc. ; Glacial Acetic Acid, 5 cc. 



Specially useful for demonstrating the granules in Ehrlich's 

 Mastzellen. The tissue must be hardened in Alcohol, as is 

 the case with bacteria. Stain for some hours, then wash out 

 in Alcohol until nearly colourless, dehydrate, clear in Cedar 

 Oil, and mount in Balsam. 



