ni. GRAM-GUNTHBR METHOD OF STAINING BAO- 

 TEEIA IN SSOTIONS.' 



(A) Without Previous Staining: 



1. Section from alcohol into anUine-water-gentian- 

 violet solution,^ from one to five minutes. 



2. Transfer to iodine solution/ two minutes. The 

 superfluous staining fluid may first be absorbed with 

 filter-paper. 



3. Alcohol, one-half minute. 



4. One per cent, hydrochloric acid alcohol, ten 

 seconds. ^ i , 



5. Wash in several watch-glasses of alcohol until en- 

 tirely decolorized and dehydrated. 



6. Cedar-oil or clove-oiL 



7. Balsam. 



(B) Staining Afterward With a Contrast Color : 



1. Section treated as above under A until after deco- 

 lorization with alcohol, then: 



2. From one-fourth to one-half minute in watery Bis- 

 marck-brown or Eosin solution. 



3. Wash and dehydrate in alcohol. 



4. OiL 



5. Balsam. 



(C) Staining Previously With a Contrast Color: 



1. Section from water to picrocarmine solution,'' 

 from twenty to thirty minutes. 



2. Wash four or five times in fresh water. 



3. Alcohol, ten minutes. 



4. w-ame as above under A (1 to 7). 



iNot appropriate for the bacilli of typhoid fever, for glanders, 

 malignant oedema, symptomatic anthrax, the gonococcus, etc., but 

 is appropriate for the bacilli of anthrax, for mouse-septicsemia, 

 tetanus, the micrococcus ascoformans, etc. 



2 (a) Aniline oil 4 cc 



Water ^. 100 cc 



Mix and filter through previously moistened filter-paper. 

 Concentrated ale. sol. gentian- violet 11 cc 



This solution remains useful for from three to four weeks. 



(b) Saturated watery solution aniline oil, filter; add concentrated 

 ale. solution gentian-violet until a marked metallic film appears on 

 the 3i,rface of the fluid. 



3 Iodine 1 part. 



Iodide of potassium 2 parts 



H,0 300 parts 



4 Picrocarmine solution (Friedlander). 



Carmine 



Ammonia aa 1 part 



Water. . . . , c 50 parts 



To this solution add concentrated watery solution of picric acid 

 until the resulting precipitate no longer dissolves Upon stirring. A 

 trace of ammonia added dissolves the precipitate. 



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