354 Tuberculosis 



methylene-blue solution for thirty seconds, washed again 

 with water until only a very faint blue remains, dried, and 

 finally mounted in Canada balsam. The tubercle bacilli 

 are colored red; the pus-corpuscles, epithelial cells, and 

 unimportant bacteria, blue. 



Pappenheim,* having found bacilli stained red by Ziehl's 

 method in the sputum of a case which subsequent post- 

 mortem examination showed to be one of gangrene of the 

 lung without tuberculosis, condemns that method as not 

 being sufficiently differential, and recommends the following 

 as superior to methods in which the mineral acids are em- 

 ployed : 



1. Spread the film as usual. 



2. Stain with carbol-fuchsin, heating to the point of steaming for a 



few minutes. 



3. Pour off the carbol-fuchsin and without washing 



4. Dip the spread from three to five times in the following solution, 



allowing it to run off slowly after each immersion: 



Corallin i 



Absolute alcohol 100 



Methylene-blue ad sat. 



Glycerin 20 



5. Wash quickly in water. 



6. Dry. 



7. Mount. 



The entire process takes about three minutes. The tubercle 

 bacilli alone remains red. 



In cases in which these methods fail to reveal bacilli 

 whose presence is strongly indicated by the clinical signs, 

 a still more exact method of searching for them is to par- 

 tially digest the sputum with caustic potash, and collect the 

 solid matter with a centrifugal apparatus. When very few 

 bacilli are present in the sputum, this method will often 

 permit them to be demonstrated. When the number is still 

 smaller, it may be possible to show their presence by guinea- 

 pig inoculation when staining methods all fail. 



The possible relation that the number of bacilli in the 

 expectoration of consumptives might bear to the progress 

 of the disease has been investigated by Nuttall. f The total 

 quantity of sputum expectorated in twenty-four hours was 

 received in covered, scrupulously clean conical glasses and 

 measured. The proportion of muco-purulent to fluid matter 

 was noted. Depending upon its viscidity and the number 



* "Berl. klin. Wochenschrift," 1898, No. 37, p. 809. 



t " Bull, of the Johns Hopkins Hospital," May and June, 1891, n, 13. 



