76 



A MANUAL OF BACTERIOLOGY 



twenty-four hours in a chemical separator (Fig. 26) 

 surrounded with ice. The sediment (containing the 

 bacilli) is drawn off from the separator by means of 

 a tap (see Fig. 26) ; and a few drops of the sediment 

 are dried on a cover-glass, and examined in the 

 ordinary way. 



Dr. W. Ktihne's methylene blue method is one of 

 the best means of staining for general purposes. It 

 ^ is prepared by dissolving 1'5 

 grammes of methylene blue in 10 

 cc. of absolute alcohol; and 100 

 cc. of an aqueous solution of 

 carbolic acid (5 per cent.) are 

 added. Preparations are stained 

 in this dye from five minutes to 

 two hours ; and sections remain 

 in it for twenty-four hours. They 

 are washed in water, followed by 

 acidulated water, 1 and are then 

 transferred to a solution of 

 lithium carbonate (5 per cent.). 

 They are again washed in water, dehydrated in abso- 

 lute alcohol, placed in aniline oil, and transferred 

 to terebene for two or three minutes. After 

 this treatment the preparations are washed in xylol, 

 and finally mounted in Canada balsam. This stain 

 is useful for the bacilli of leprosy, glanders, tuber- 

 culosis, arid almost any microbe. 



Cover-glass preparations of anthracic blood, etc., 

 are floated on a hot alcoholic solution of fuchsine 



FIG. 26. 

 CHEMICAL SEPARATORS. 



1 Two or three drops of hydrochloric acid to 100 cc. of 

 distilled water. 



