IV. GRAM METHOD OF STAINING BACTERIA IN 

 COVER-GLASS PREPARATIONS. 



1. Hold the cover-glass with forceps, and flood its 

 surface with aniline-water-gentian-violet solution (See m, 

 foot-note 2, a and b). Place glass in a flame until the fluid 

 boils,^ or stain in the cold from two to five minutes with 

 the same fluid in a watch-glass. 



2. Iodine solution (See III, foot-note 3), two minutes. 



3. Acid alcohol (HCl. one per cent.), ten seconds. 



4. Alcohol until thoroughly decolorized. 



5. Contrast stain with water solution of eosin or Bis- 

 marck-brown, one minute. 



6. Wash in water. 



7. Dry and mount. 



iBoiling the fluid is only necessary when staining the bacillus 

 of tuberculosis. 



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