DIFFERENTIAL STAINS III 



5. Wash in water. (A pale red colour returns to 

 the film). 



6. Wash in alcohol till no more colour is discharged. 

 (This often, but not invariably, removes the stain 

 from acid-fast bacilli other than tubercle; e. g., smegma 

 bacillus.) 



7. Wash in water. 



8. Counterstain in weak methylene-blue. (Stains 

 non-acid-fast bacilli, leucocytes, epithelial cells, etc.) 



9. Wash in water, dry, and mount. 

 Pappenheim's Method. 



This method is supposed to differentiate between 

 B. tuberculosis and other acid-fast micro-organisms. 



1. Prepare and fix film in the usual way. 



2. Stain in carbol-fuchsin without heat for three 

 minutes. 



3. Without previously washing in water treat the 

 film with three or four successive applications of coralin 

 (Rosolic acid) solution. 



Corallin i gramme 



Methylene-blue 



(saturated alcoholic solution) . 100 c.c. 



Glycerine 20 c.c. 



4. Wash in water. 



5. Dry and mount. 



Neisser's Method Modified. (To demonstrate diph- 

 theroid bacilli.) 

 Stain I. 

 Measure out and mix 



Methylene-blue, saturated alcoholic 



solution 4-0 C-C. 



Acetic acid, 5 per cent, aqueous solu- 

 tion 96.0 c.c. 



Filter. 

 Stain II. 

 Weigh out 



Neutral red 2.5 grammes 



