HO STAINING METHODS 



Modified Gram=Weigert Method. (To demonstrate 

 trichophytain hair.) 



1. Soak the hairs in ether for ten minutes to remove 

 the fat. 



2. Stain thirty minutes in a tar-like solution of 

 aniline gentian violet (prepared by adding 1 5 drops of 

 the alcoholic solution of gentian violet to 3 drops of 

 aniline water) . 



3. Dry the hairs between pieces of blotting paper. 



4. Treat with perfectly fresh iodine solution. 



5. Again dry between blotting paper. 



6. Treat with aniline oil to remove excess of stain. 

 (If necessary, add a drop or two of nitric acid to the oil.) 



7. Again treat with aniline oil. 



8. Treat with aniline oil and xylol, equal parts. 



9. Clear with xylol. 



10. Mount in xylol balsam. 



To obtain the best differentiation the preparation 

 should be repeatedly examined microscopically (with 

 a J-inch objective) between steps 5 and 9, as the actual 

 time involved varies with different specimens. 



Ziehl=Neelsen's Method. (To demonstrate tubercle 

 and other acid- fast bacilli.) 



1. Smear a thin, even film of the specimen on the 

 cover-slip by means of the platinum loop. (In the case 

 of sputum, if it is a very watery specimen, allow the 

 film to dry, then spread a second and even a third layer 

 over the first.) 



2. Fix by passing three -times through the flame. 



3. Stain in hot carbol-fuchsin (as in staining for 

 spores) for five to ten minutes. (This stains every- 

 thing on the film.) Avoid over-heating. 



4. Decolourise by dipping in sulphuric acid, 25 per 

 cent. (This removes stain from everything but acid- 

 fast bacilli; e. g., tubercle, leprosy, and smegma bacilli 

 and the film turns yellow.) 



