24 JOURNAL OF THE [January, 



whiteness, or has acquired a bluish tint, the heat destroys the 

 lamp. The inconvenience arising from the rapid exhaustion of 

 the strength of the electric current, may be partly obviated by 

 the use of a storage battery. I have seen this device employed 

 with marked success." 



BACILLUS LEPR^ AND BACILLUS TUBERCULOSIS. 



Mr. E. A. Schultze read a translation which he had made, of 

 an article recently contributed by Dr. P. Baumgarten to the 

 "Zeitschrift fiir Wissenschaftliche Mikroskopie," on "Methods 

 for Determining the Difference between Bacillus leprce and B. 

 tuberculosis.''' Its purpose was to show that these bacilli, though 

 nearly identical in form, may be correctly and easily distinguished 

 from each other by coloration ; and it describes four processes 

 of staining, three of which are given below. 

 First Process : 



1. Pour five or six drops of saturated alcoholic solution of 

 fuchsine into a small watch-glass containing distilled water. 



2. Float on the dye for six or seven minutes several dry cover- 

 glasses laden with fresh bacilli. 



3. Decolor for fifteen seconds in absolute alcohol mixed with 

 nitric acid in the proportion of ten parts to one. 



4. Put into distilled water in order to remove the acid. 



5. Moisten with aqueous solution of methylene-blue, and ex- 

 amine at once with a Ath-or xVth-inch homogeneous-immersion 

 lens ; and the Bacilli leprcz will show themselves as well-defined 

 red rods, while the B. tuberculosis will present no color whatever. 

 Second Process: 



1. Place for not more than fifteen minutes the bacilli-bearing 

 material into the fuchsine solution above described. 



2. Decolor for thirty seconds in the mixture of alcohol and 

 nitric acid. 



3. Wash in distilled water. 



4. Dehydrate in absolute alcohol three or four minutes. 



5. Put into oil of bergamot, and examine with homogeneous- 

 immersion objective. The Bacilli leprce will be easily recognized 

 as shining red rods on a blue ground, while nothing will be seen 

 of the B. tuberculosis. 



Third Process: 

 I. Place the bacilli-bearing sections for two or three minutes 



