132 LABORATORY GUIDE IN BACTERIOLOGY 



2. Special study. — Method of staining acid-proof 

 bacilli. 



a) Pick out purulent matter from the sputum of a 

 tuberculous patient and spread carefully on a cover 

 glass. 



b) Dry and fix as usual. 



c) Heat with carbol fuchsin over a small flame for 

 one minute or on a water bath for two minutes. 



d) Decolorize with acid alcohol (2 per cent HCl in 

 80 per cent alcohol) until the film has lost almost all 

 its color. 



e) Wash in water and counterstain with methylene 

 blue for 10 seconds (cold). 



/) Wash again and mount in balsam. 



Note. — ^Make a second preparation, substituting anilin gen- 

 tian violet for carbol fuchsin, and Bismarck brown for methylene 

 blue. 



3. Special study. — Stain MoUer's grass bacillus 

 from an agar culture by the same method, omitting the 

 counterstain. 



4. Special study. — Make a smear from a culture 

 of MoUer's grass bacillus in milk and stain this smear 

 for acid-proof bacilli. 



SECTION II A 



MISCELLANEOUS ORGANISMS: BACILLUS MALLEI, 



BACILLUS MBLITENSES, BLASTOMYCES 



DERMATITIDIS 



B. mallei has been the cause of more accidents 

 among bacteriologists than any other organism, and 

 it is therefore not prudent to study this organism in 

 the laboratory unless there is thorough supervision. 



