58 GENERAL BACTERIOLOGY LESSON xin 



(a) Leave in the stain for twenty to thirty minutes. 



(b) Wash it quickly in '6 per cent saline solution. 



(c) Decolourise it in hydrochloric acid (25 per cent) for 

 a few seconds, until the red tint disappears. 



(d) Transfer the section to 70 per cent alcohol, and with 

 a needle move it about till no more red is washed out. 



(e) Eemove the alcohol with *6 per cent saline solution. 

 (/) Now counterstain the section in Loffler's methylene- 



blue for one to two minutes. 



(9) Wash thoroughly in '6 saline solution. 



(h) Dehydrate in absolute alcohol. 



(i) Clear in xylol and mount in xylol balsam. 



Examine with low and high powers and -^ in. oil 

 immersion. The bacilli are stained red and the 

 tissues blue. 



