28 PRACTICAL BACTERIOLOGY 



glass or small porcelain evaporating dish of Ehrlich's anilin water 

 fuchsin or gentian violet, or ZiehFs carbol fuchsin, heated until 

 vapour arises, when it is set aside to cool, and allow the stain to work 

 in for one minute. ' This process is repeated five times.' 1 



3. Decolorize with 3 per cent. HC1. alcohol, allowing one minute 

 to work in ; the spores remain stained. 



4. Wash the cover-glass with water. 



5. Contrast stain, with methylene blue, if the spores are stained with 

 the fuchsin stain ; if with the violet stain, then use a Bismarck brown 

 as a contrast. 



6. Wash in. water, dry, and mount in xylol balsam. 



Result. With juchsin, the spores are stained red and the bacilli 

 blue ; with gentian violet, the spores are stained blue and the bacilli 

 brown. 



XXVII. SPECIAL METHOD OF STAINING THE ENDO- 

 SPORES OF BACILLUS ANTHRACIS. 



1. Make a hanging-drop culture (see method, 6) from the 

 heart's blood of an inoculated mouse. 



2. Place the hanging drop in an incubator from twenty-four to 

 forty-eight hours, at 35 C., until spores are developed. 



3. Remove the cover-glass from the slide. 



4. Air dry. 



5. Remove the vaseline with xylol. 



6. Fix in the flame in ordinary way. 



7. Proceed as at process No. 2. (Ordinary method of staining 

 Spores, see 26). 



XXVIII. THE EXAMINATION OF BLOOD BY COVER- 

 GLASS METHODS. 



1. Handle the cover-glass with forceps only, as the heat of the 

 hand injures the specimen. 



2. Place an extremely small drop of blood on the cover-glass, either 

 directly from the living subject or with the platinum loop. 



3. Spread the drop of blood by placing a second cover-glass on the 

 top of the first. Avoid pressure, and draw the two cover-glasses 

 apart in a horizontal direction. 



4. Air dry under a glass cover. 



5. The cover-glass can be fixed by either of the following 

 methods : 



