SECTION SEVEN 



B. Safranin O aqueous 0-2% . . . . i volume 

 Acetic acid 0-1% .. .. .. 3 volumes 



Technique: 



1 . Spread smears of infected tissue on scrupulously clean slides ; 

 then allow to dry. 



2. Stain with solution A for three minutes. 



3. Pour off excess stain; then without washing counterstain for 

 one to three seconds in the safranin solution. 



4. Wash in running water. 



5. Drain and dry thoroughly, and examine. 



Results: 



Rickettsiae, blue ; protoplasm and nuclei of the cells, red. 



CRYSTAL VIOLET 

 For bacterial capsules 



Solutions required: 



A. Crystal violet 0-5%. 



B. Copper sulphate crystals . . 5 gm. 

 Distilled water . . . . . . 25 ml. 



Technique: 



1. Stain air-dried smears for three to four minutes in the 

 crystal violet solution. 



2. Rinse well in the copper sulphate solution. 



3. Blot dry, and examine. 



Results: 



Capsules are stained light blue, while the bacterial cells are dark 

 blue. 



357 



