STAINING 7 1 :. 



1. Tissues taken from water are stained five mimile.~. 



2. Wash in water. 



3. Dehydrate rapidly in absolute alcohol. The alcohol removes some 

 of the safranin, giving a regressive effect. 



SINGLE STAINS WITH CYTOPLASMIC DYES 



Eosin. This dye is a coal-tar derivative. There are no less than 

 seventeen varieties of the dye on the market, of which five are in general 

 use. These are: (1) yellowish alcoholic; (2) bluish alcoholic; (3) 

 yellowish watery; (4) bluish watery; (5) pure French eosin. The most 

 reliable of these dyes are manufactured by Griibler. The first and fifth 

 varieties are to be recommended as blood stains, the first and fourth 

 are the best for general use. Two distinct methods are based upon 

 this choice of dyes. 



Method I: 



Yellowish alcoholic eosin. 1 grm. 



70 per cent, alcohol 100 c.c. 



This stock solution is usually diluted with four to ten volumes of 

 70 to 95 per cent, alcohol just before using. The stain is preferably 

 preceded by the use of a nuclear dye, after which the sections should 

 be dehydrated in 95 per cent, alcohol. 



1. Stain in the diluted eosin, one to five minutes, or until the sec- 

 tions become a bright red color. 



2. Wash quickly in absolute alcohol, clear, and mount. The color 

 is dissolved out during this process, producing some differentiation by 

 regression. 



Method II: 



Bluish watery eosin 1 grm. 



Distilled water 100 c.c. 



The stock solution should be diluted with one to four volumes of 

 distilled water before using. 



1. Tissues are taken from water and placed in the dilute eosin, one 

 to five minutes. 



2. Wash quickly in water to remove the excess of the dye. 



3. Pass radially through graded alcohol, clear, and mount. 

 Slight differentiation may be obtained by prolonging the washing 



in water, otherwise the stain is progressive. Much greater differenti- 

 47 



