APPARATUS, MATERIAL, AND REAGENTS. 13 



22. Magenta solution (Gibbes). 



Magenta ..... 2 

 Aniline oil ..... 3 

 Alcohol (Sp. Gr. -830) .; . .20 

 Distilled water 20 



23. Methylene blue. 



(a) Concentrated alcoholic solution. 



(<$) Aqueous solution. 



Methylene blue .... 2 

 Alcohol . . . . . -15 

 Water 85 



(c) Koch's solution. 



Concentrated alcoholic solution of 



methylene blue i 



Ten per cent, potash solution . . 2 



Distilled water .... 200 



(a} Loffler's solution. 



Concentrated alcoholic solution of 



methylene blue . . . .30 

 Solution of potash i 10,000 . . 100 



24. Methyl violet. 



(a) Concentrated alcoholic solution. 



