V. ZIEHL-GABBBT METHOD OP STAINING TUBER- 

 CLE BACILLI IN COVER-GLASS PREPARATIONS. 



(a) 1. Spread a small portion of the material (sputum, 'I 

 cheesy mass, mucus, etc.), that is most ' likely to con- 

 tain the bacilli, upon the cover-glass in as thin a layer as 

 possible. 



2. Dry and "fix." 



3. Flood the glass (held in the forceps) with Ziehl's 

 carbol-fuchsin solution.^ 



4 Boil three or four times and allow the fluid to re- 

 main on the glass from one to five minutes. The boiling 

 is accomplished by holding the cover-glass in the lower 

 portion of the Bunsen flame until the staining fluid 

 steams; then slowly raise the glass to the top of the 

 flame and the fluid will boil; immediately lower again 

 and repeat. 



5. Wash in water and partially dry the cover-glass 

 with filter-paper. 



6. Flood the glass with Gabbet's solution,^ from one 

 to three minutes, according to the thickness of the prepa- 

 ration and to the intensity of the fuchsin stain. 



7. Wash in water; place the cover-slip ("butter" side 

 down) on the slide ; absorb the water with filter-paper, etc., 

 and examine ; or, to obtain a better contrast, stain (this is 

 110 longer the method of Ziehl-Gabbet). 



(b) 7. After 6, wash in water. 



8. Stain as usual with 2 per cent, methylene-blue 

 (See 1, foot-note 2, a). 



9. Wash in water. 



10. Mount, etc., or, after 4: ^ 



(c) 5. Wash in water. 



6. Decolorize in 25 per cent, nitric acid, from ten to 

 thirty seconds. 



7. Complete decolorization in alcohol. 

 S. Wash in water. 



9. Stain with methylene-blne, etc., as above (b). 



1 Ziohl's Carbol-fuchsin Solution: 



Fuchsin 1 s. 



Alcohol 10 cc. 



Carbolic Acid, ^ per cent 100 cc. 



A¥arm to dissolve the fuchsin, and when cool filter. 



2 Gabbet's Solution: 



Methyl ene-blue 1 to 2 g. 



H.SOi ; 25 per cent 100 cc. 



niter. 



23 



