190 INORGANIC AGENTS 



changes to purple and the permanganate is formed. 3 Kj 

 MnO, + 2 H,0 = 2 KMnO, + 4 KHO + MnO,. The liquid 

 is neutralized with carbonic dioxide gas and evaporated. 



Properties. — Slender, monoclinic prisms, of a dark purple 

 color, odorless, and having a taste at first sweet, but after- 

 wards disagreeable and astringent ; permanent in dry air ; 

 soluble in 16 parts of water ; undergoes decomposition with 

 alcohol ; reaction neutral. 



Incomjxitibles. — It is very readily deoxidized in the pres- 

 ence of organic matter. 



Dose. — H., gr.xv.-xx. (1.-1.3) in one pint of water; D., 

 gr.i.-ii. (.06-.12), in pill, or tablet, with kaolin. 



ACTION OF POTASSIUM PERMANGANATE. 



External. — Potassium permanganate, like hydrogen 

 dioxide, is a powerful oxidizing agent. It quickly parts 

 with its oxygen in contact with organic matter, largely in the 

 form of ozone, and is broken up into black oxide of manga- 

 nese and potassa. Solutions, which are of a purple hue, 

 change into a dark brown color when this transformation 

 occurs, and are no longer of any medicinal value. This 

 action is exceedingly rapid and transient, and its effects 

 correspondingly so on the tissues. For this reason, and 

 because bacteria are so combined with organic matter in the 

 tissues, its action is largely exerted on the latter, iand 

 potassium permanganate is, therefore, a better antiseptic 

 than disinfectant. Outside of the body, permanganate of 

 potash is a disinfectant, but it is too expensive for general 

 purposes. In powder' it is slightly caustic, owing to the 

 potassa set free in its decomposition ; and in solution is 

 stimulant to the tissues. A solution of permanganate of 

 potash is a deodorizer when in contact with putrid and 

 decomposing matter, but is not of the slightest value as a 

 deodorizer and disinfectant to premises when simply stand- 

 ing in vessels, as frequently advised. There is no danger 

 irom absorption of potassium permanganate when applied 

 to the body. 



