148 BACTERIOLOGY. 



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. 



Kuhne's carbolic methylene-blue method. Stain the 

 sections in the following solution 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 into 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 again thoroughly washed in water ; then into 

 absolute alcohol containing enough methylene-blue in 

 substance to give it a tolerably dense color, then for 

 a few minutes into aniline oil to which a little methy- 

 lene-blue in substance has been added ; then com- 

 pletely rinse out in pure aniline oil, from this into 

 thymol or oil of turpentine for two minutes, 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 decolor- 

 ized to render the bacteria visible and admit of the use 

 of contrast stains. 



Weigert's modification of Gram's method for sections. 

 Stain the sections in Ehrlich's aniline- water gentian-violet 



