DISINFECTION FOR CONTAGIOUS DISEASES. 865 



sive metal pails be used. Agate vessels or tin pails are to be pre- 

 ferred. All solutions should be labeled "poison," and to avoid 

 accidents none should be kept on hand. 



(5) Formalin and formaldehA'de gas have been found very effica- 

 cious as sanitary agents. Formalin is the commercial name for the 

 40 per cent solution of formaldehyde gas in water, and is one of the 

 most powerful antiseptic and disinfectants that we possess. Solu- 

 tions of this strength are manufactured by different commercial 

 houses and sold by the drug trade under the name of " formalose" 

 and " formal." In this connection it should be mentioned that while 

 the 40 per cent solution of formaldehyde gas and formalin are ex- 

 actly the same thing, the former can be purchased at 33^ to 64 per 

 cent less than the latter. Formalin, diluted with water in the pro- 

 portion of 1 pint to 30 parts of water, or 4 ounces to each gallon of 

 water, may be applied, and it may thus be used as a wash or as 

 a spray on all paints, metals, and woodwork, as well as on clothing 

 and other fabrics, without injuring them. It may also be applied 

 to floors, walls, and woodwork in whitewash by mixing 1 part to 

 30 i^arts of limewash, or 4 ounces to each gallon of limewash. 

 Formalin has the appearance of water and in the strong solu- 

 tion is poisonous, but when diluted as recommended above it is not 

 dangerous. The fumes given off by it, however, are very disagree- 

 able and irritating to the eyes and nasal mucous membranes. One 

 and one-half ounces of formalin added to 1 gallon of water is a valu- 

 able agent for the disinfection of the skin or septic wounds, but is 

 somewhat painful and irritating to raw surfaces. 



Formaldehyde is a gas which is soluble in 2^ parts of water (40 

 parts of formaldehyde gas to 100 parts of water) ; this solution 

 constitutes the formalin of commerce. The use of formaldehyde gas 

 is in most cases impracticable for stable disinfection. In case the 

 stable is not too large and can be made almost air-tight the genera- 

 tion of formaldehyde gas, after removing all the animals, will be 

 found very serviceable. It penetrates all parts of the stable. — ^the 

 walls, crevices, floors, ceiling — and is probably the best fumigating 

 disinfectant that we have. 



Probably one of the most simple and practical methods of liber- 

 ating this gas is by means of the chemical reaction which takes place 

 when formalin is poured upon permanganate of potassium. For 

 each 1,000 cubic feet of air space, 16| ounces of crystallized or 

 powdered permanganate of potassium, is placed in a wide-surfaced 

 pan; 20 ounces of formalin is then poured upon it, and the stable 

 immediately closed for a period of 12 hours or longer. This method 

 is efficient only when it is possible to seal tightly the place to be 

 disinfected, and should be used only by experienced persons. 



