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described, serve the purpose of demonstrating 1 the pres- 

 ence of the anthrax bacillus in the different organs and 

 tissues of the body. The form, size, etc., of the bacillus 

 found under these conditions should be compared with the 

 growth of the organism in pure cultures in different 

 media. For this purpose make hanging-drop examina- 

 tions and permanent simple stains of the bacillus grown 

 in the stich culture in gelatin, on ordinary agar, and on 

 calcium hydrate agar. The preparation of impression 

 cover-glasses of the anthrax colonies and simple stains of 

 bouillon hanging-drop culture have been mentioned. 



Double stain for spores. The growth of the anthrax 

 bacillus on calcium hydrate agar when examined, as 

 mentioned above, in hanging-drop will show the presence 

 of an abundance of bright, highly refracting oval bodies, 

 or spores, which may be observed free and also within the 

 parent cell. Simple stains of this growth with fuchsine, 

 etc., will show the bacilli deeply stained, whereas the 

 spores remain colorless. This is undoubtedly due to the 

 dense impenetrable wall which surrounds the spores and 

 prevents the dye from passing into the spore, as well as to 

 a special composition of the spore contents. By proper 

 treatment with strong anilin dyes it is possible to force 

 the stain into the spore. Once within the spore it is as 

 difficult to remove the dye as it was to cause it to enter. 

 By suitable decoloration it is, therefore, possible to remove 

 the stain from everything on the cover-glass, except from 

 the spores. Then, on the application of a contrast color the 

 specimens will show a bright red spore within a blue 

 bacillus. The method of double staining of spores is as 

 follows : 



The cover-glass preparation from the calcium hydrate 

 agar is dried in the air and fixed in the usual manner. 

 The cover-glass is held in the forceps, in the left hand, 

 with the specimen side up and covered with a solution of 

 carbolic fuchsine. This is held over a Bunsen flame, so 

 that vapors are given off from the liquid. Active ebullition 



