DISINFECTANTS AND DISINFECTION. 167 



many advantages as a disinfectant. It does not injure, fade or decolorize 

 cloth or other colored fabric and does not corrode metal (excepting hot steel 

 and iron). It kills spores and is an efficient deodorant. Albuminous 

 matter does not interfere with its action and hence it is an efficient sick-room 

 disinfectant. It disinfects and deodorizes all discharges from patients 

 very quickly and completely, when used in 4 to 5 per cent, solutions. 



As a gaseous disinfectant it is active in a moist, warm atmosphere. It 

 does, however, not kill insects and other higher organisms and in this 

 regard it is inferior to sulphur dioxide, but has the advantages of not decoloriz- 

 ing fabric and being a better deodorant. There are several proprietary dis- 

 infectants composed of soap and formalin, as lysoform. 



E. Sulphur. Sulphur in itself is odorless, tasteless and wholly inert as a 

 germicide, but when undergoing oxidation into sulphur dioxide (combustion), 

 in the presence of moisture, it is a very active disinfectant and is at the same 

 time fatal to insects and in fact to all forms of animal life, including rats, 

 mice, etc. But it cannot be used to disinfect fine fabrics, paintings, books, 

 etc., because of the destructive effects upon pigments. 



Under ordinary conditions the gaseous substances, as formaldehyde 

 (formalin) and sulphur dioxide, are surface disinfectants only and are used 

 where surface disinfection is all that is required, as in the sterilization of 

 clothing, wood work, walls, ceilings, pictures, furniture, etc. 



F. Bichloride of Mercury. This is the most potent and most extensively 

 used of all antiseptics. A i-iooo aqueous solution (used hot whenever and 

 wherever possible) makes a most satisfactory germicidal wash for floors, 

 walls, wood work of all kinds, in fact anything requiring disinfection, ex- 

 cepting metals which would be corroded (excepting of course platinum, 

 gold, silver) and substances rich in albuminous matter as pus, sputum, and 

 other sick room discharges, which are coagulated by this germicide, checking 

 further action. 



The i-iooo solution is sufficiently powerful to kill all non-sporogenous 

 bacteria at the ordinary room temperature in one-half hour. For spores a 

 stronger solution (1-500) and longer exposure are desirable (one hour). 



The chief disadvantages to the use of corrosive sublimate are its highly 

 toxic nature, its corroding effect upon metals and its coagulating effects upon 

 albumen which hinders penetration. It should also be borne in mind that 

 soap interferes with the action of corrosive sublimate. 



A i-iooo solution is made as follows: 



Bichloride of mercury, 61 1/2 grs. 



Citric acid or salt, 61 1/2 grs. 



Water, i gal. 



The salt or citric acid is added to retard the decomposition of the bi- 

 chloride. Tablets are now on the market prepared from mercury cyanide. 



