164 BACTERIOLOGY. 



alcohol, and then in xylol, from which they may be 

 mounted in the manner given. 



Especially brilliant results are obtained when tissues 

 containing anthrax bacilli are stained by this process ; 

 the bacilli will be of a deep blue color, while the sur- 

 rounding tissues will be of the color used as contrast. 



Kuhnds carbolic methylene-blue method. Stain the 

 sections in the following solutions for from one-half to 

 one hour : 



Methylene-blue, in substance . . . .1.5 grammes. 

 Absolute alcohol ....... 10 c.c. 



Rub up thoroughly in a mortar, and when the blue 

 is completely dissolved, add gradually 100 c.c. of a 5 

 per cent, solution of carbolic acid. (The solution de- 

 composes after a short time ; it should be made fresh 

 when needed.) From this the sections are washed out 

 in water, then in 1.5 to 2 per cent, hydrochloric acid in 

 water, from this they are transferred to a solution of 

 lithium carbonate of the strength of six to eight drops 

 of a concentrated watery solution of the salt to ten drops 

 of water, and from this they are again thoroughly washed 

 in water, then in absolute alcohol containing enough 

 methylene-blue in substance to give it a tolerably dense 

 color, then for a few minutes in aniline oil to which a 

 little methylene-blue in substance has been added, then 

 completely rinse out in pure aniline oil, from this they 

 are passed into thymol or oil of turpentine for two min- 

 utes, and then into xylol, from which they are mounted 

 in xylol-balsam. The advantages of this method are 

 that it is generally applicable, and by its use the bacteria 

 are not robbed of their color, whereas the tissues are 

 sufficiently decolorized to render the bacteria visible and 

 admit of the use of contrast stains. 



