BLOOD STAIN 97 



and dissolve in 



Distilled water 100.0 c.c. 



BLOOD STAINS 



When watery solutions of medicinal methylene blue 

 and water soluble eosins are mixed a precipitate is 

 formed which is soluble only in alcohol, and solutions of 

 this precipitate impart a peculiar reddish-purple 

 colour to chromatin. This compound was first used 

 by Romano wsky to demonstrate malarial parasites, but 

 various modifications are now employed for staining 

 blood films generally, and also for bacteria and pro- 

 tozoa. The best modifications of the original Roman- 

 owsky are those of Jenner and Leishman Jenner 

 being most suitable for the histological study of the 

 blood, and Leishman for the demonstration of protozoa. 



Jenner 's Stain. 



A. Weigh out: 



Eosin aqueous yellow ... .6.0 grammes 



Dissolve in 



Distilled water (non-alkaline) . . 250 c.c. 



This will make a thick solution. 



B. Weigh out : 



Methylene blue (medicinally pure) Hoechst . 5.0 grammes 



Dissolve in 



Distilled water (non-alkaline) ... 250 c.c. 



1. Add B to A very slowly, stirring all the time. A 

 viscous precipitate forms which frequently loses its 

 viscosity when heat is applied. (This explains the 

 necessity of mixing slowly) . 



2. Evaporate slowly in a porcelain basin, stirring 

 occasionally, on a water bath at 55 C. When a paste 



7 



