THE PREPARATION OF SECTIONS 627 



Van Gieson's Stain. 



Treat as above to remove paraffin. 



Stain with hjematoxylin fifteen to twenty minutes and blue well in 

 tap water. 



Stain with van Gieson half to one minute (picric acid i| per cent. 

 of acid fuchsin). 



Treat with spirit, oil of cloves, xylol and mount. 



The haematoxylin stains the nuclei and parasites blue. 

 The picric acid stains the protoplasm of the cells yellow. 

 The fuchsin stains the fibrous tissue red. 



To show Malarial Parasites in the Brain. 



Remove the paraffin. Stain with haematoxylin twenty minutes and 

 blue well in tap water. 



Treat with acid alcohol one to four seconds, wash well. 

 Treat with spirit, oil of cloves, xvlol and mount. 



To Embed in Celluloidin. 



Celluloidin is a product of gun cotton and looks like glass 

 cotton . 



It must be packed in water for transit. 



It is a gummy transparent substance, and is useful for holding the 

 brain tissue and the malarial parasites together in subtertian cases. 



It must be dried before using. 



Place the section in spirit twenty-four hours, in another solution 

 of spirit for the same period, in absolute alcohol twenty-four hours, in 

 alcohol and ether for twenty-four hours, in thin celluloidin twentv- 

 four hours. 



Pour some thick celluloidin on a wooden block and place the tissue 

 on it; leave it in the air for a few minutes. 



Place in 60 per cent, spirit to harden it until it is cut. 



To mount and stain the Section. 



Place in a watery haematoxylin stain twelve minutes. (Watch 

 glasses are the best for these processes.) 



Wash and blue well in tap water. 



Treat with acid alcohol until red, five seconds. 



Wash well and stain Vvith alcoholic eosin three to four 

 minutes. 



Pass through three baths of spirit. 



Clear in carbol xylol and mount. 



A low power shows the brain capillaries plainl\' because of the 

 malarial pigment present in subtertian cases. 



