106 BIOLOGY AND TECHNIQUE 



PAPPENHEIM'S METHOD. 1 The method of Pappenheim is devised 

 for the purpose of differentiating between the tubercle bacillus and the 

 smegma bacillus. Confusion may occasionally arise between these two 

 microorganisms, especially in the examination of urine where smegma 

 bacilli are derived from the genitals, and less frequently in the examina- 

 tion of sputum where smegma bacilli may occasionally be mixed with 

 the secretions of the pharynx and throat. 



Preparations are smeared and fixed by heat in the usual way. 



Stain with hot carbol-fuchsin solution for two minutes. 



Pour off dye without washing and cover with the following mixture: 



Corallin (rosolic acid) 1 gm. 



Absolute alcohol 100 c.c. 



Methylene-blue added to saturation 



Add glycerin 2 20 c.c. 



This mixture is poured on and drained off slowly, the procedure being 

 repeated four or five times, and finally the preparation is washed in 

 water. The combination of alcohol and rosolic acid decolorizes the 

 smegma bacilli, but leaves the tubercle bacilli stained bright red. 



BUNGE AND TRAUTENROTH METHOD. 3 This method is designed .to 

 differentiate between the tubercle and smegma bacilli. 



Smear and fix by heat in the usual way. 



Wash with absolute alcohol to remove fat. 



Treat with five per cent chromic acid for fifteen minutes. 



Wash in several changes of water. 



Stain with hot carbol-fuchsin for five minutes. 



Decolorize with sixteen per cent sulphuric acid for three minutes. 



Counterstain with alcoholic methylene-blue for five minutes. 



Wash in water, dry, and mount. 



By this method the tubercle bacillus remains red, the smegma bacil- 

 lus is decolorized. 



BAUMGARTEN'S METHOD. 4 This method is recommended by the 

 author for differentiation between the bacillus of tuberculosis and the 

 bacillus of leprosy and depends upon the fact that the tubercle bacillus 

 is less easily stained than Bacillus leprse. 



Smears are prepared and fixed by heat in the usual way. 



1 Pappenheim, Berl. klin. Woch., 1898. 



2 The glycerin is added after the other constituents have been mixed. 



3 Bunge und Trautenroth, Fortschr. d. Med., xiv, 1896. 

 5 Baumgarten, Zeit. f. wissensch. Mikrosk., 1, 1884. 



