Staining and Mounting Micro-Organisms 161 



blue. Immerse the sections for an hour. Wash in 

 distilled water, and then in a J per cent, solution of acetic 

 acid in distilled water. Wash away the acid with water, 

 dehydrate in alcohol, clear in oil of cedar or bergarnot, and 

 mount in Canada balsam. 



Anthrax bacilli may also be stained by Gram's method. 



Gram's Method. Solution A. Saturated alcoholic 

 solution of gentian violet, 11 parts; saturated watery solu- 

 tion of aniline, 100 parts. Mix well together, and filter. 



Solution B. Iodine, 1 part ; iodide of potassium, 3 parts ; 

 distilled water, 300 parts. 



Solution C. Saturated aqueous solution of vesuvin. 



Take the section from alcohol, and place in Solution A 

 for one to three minutes. Wash in alcohol, and transfer to 

 Solution B for three minutes. Wash in alcohol, and place 

 in Solution C for five minutes. Wash in distilled water, 

 dehydrate, clear in oil of cedar or bergamot, and mount in 

 Canada balsam. 



Leprosy Bacillus. Stain in the following for three 

 minutes : 



Fuchsin ... ... ... ... 1 gramme, 



Eectified spirit ... ... ... 20 c.c., 



Distilled water ... ... ... 80 c.c., 



then place for thirty seconds in a solution consisting of 

 90 per cent., alcohol 10 parts, and nitric acid 1 part. Wash 

 in water, dehydrate in absolute alcohol, clear in cedar-oil, 

 and mount in Canada balsam. 



Diphtheria Bacillus. Employ Loffler's alkaline blue and 

 proceed as for anthrax. 



Glanders Bacillus. 



Kuhne's Method. Methylene blue, 1 gramme ; 

 absolute alcohol, 10 c.c. When all the blue has dissolved, 

 add 100 c.c. of a 5 per cent, watery solution of carbolic 

 acid. 



The sections are transferred from alcohol to the above 

 stain for half an hour. Wash in water, and place in a weak 



11 



