DISINFECTANTS AND ANTISEPTICS. 207 



Cupric Sulphate {Blue Vitriol). — This salt is quite an effi- 

 cient disinfectant. In a solution of 1-3000 the spirillum of 

 cholera is destroyed in ten minutes. A 5 per cent, solution 

 will kill the typhoid bacillus in ten minutes. A solution of 

 from 2 to 3 per cent, in strength can be relied upon to destroy 

 all pathogenic organisms that do not form spores. 



Zinc Sulphate. — This salt is a very feeble disinfectant. Pus 

 cocci are not destroyed in two hours by a 20 per cent, solu- 

 tion. As a deodorizer it has about the same value and acts 

 in the same way as ferrous sulphate. 



Zinc Chloride. — A 2 per cent, solution will kill pus cocci 

 after an exposure of two hours. It is therefore a much more 

 powerful disinfectant than the sulphate. 



Disinsection of Dejecta and Urine. — A 4 per cent, solution 

 of calcic hypochlorite (chloride of lime) is most efficient and 

 rapid for this purpose. A convenient solution contains 6 

 ounces of the salt to i gallon of water. The excreta should 

 be received in a suitable vessel and immediately mixed with 

 an equal bulk of the disinfectant. The contents of the vessel 

 should be allowed to stand for one hour before emptying. 

 A 20 per cent, milk of lime is just as efficient, and possesses 

 the advantage of cleanliness and lack of odor. It should be 

 used in the same quantity and allowed to act for the same 

 length of time. A 5 per cent, solution of carbolic acid may 

 be used, but should be allowed to act for at least four hours. 



Disinfection of Sputum. — The chemical disinfection of tuber- 

 culous sputum is somewhat difficult on account of the large 

 amount of albumin in it and the fatty matter associated with 

 the bacillus of tuberculosis. Dilute solutions of bichloride of 

 mercury are apt to be decomposed and rendered inert by the 

 albumin. Carbolic acid is open to the same objection, but its 

 combination with hydrochloric acid can be used successfully 

 in a strength of 5 per cent. each. Milk of lime cannot be 

 rehed upon for this purpose. A 4 per cent, solution of calcic 



