TO DEMONSTRATE CAPSULES 123 



9. Wash thoroughly with xylol. 



10. Decolourise and dehydrate rapidly with abso- 

 lute alcohol until there remains only a very faint bluish 

 tint. 



11. Clear with xylol. 



12. Mount in xylol balsam. 



(Then fibrin and hyaline tissue are stained deep blue, 

 whilst bacteria which " stain Gram" appear of a deep 

 blue- violet colour.) 



Unna=Pappenheim Method. 



Stain. 



Weigh out and mix 



Methylene green 0.15 gramme 



Pyronin 0.25 gramme 



and dissolve in 



Carbolic acid 0.5 per cent, aqueous solution . . 78 c.c. 



Measure out 



Alcohol 2.5 c.c. 1 



, > and add to the stain. 



Glycerine 20.0 c.c. J 



Method.- 



1. Place tissue in the above stain for ten minutes. 



2. Differentiate and dehydrate with absolute alcohol. 



3. Clear in xylol. 



4. Mount in xylol balsam. 



To Demonstrate Capsules. 



1. MacConkey's Method. Stain precisely as for 

 cover-slip films (vide page 100). 



2. Friedldnder's Method. 



Stain. 



Gentian violet, saturated alcoholic solution . 50 c.c. 



Acetic acid, glacial 10 c.c. 



Distilled water . . 100 c.c. 



