72 BACTERIOLOGY 



Much difference of opinion exists regarding the value of it as a 

 disinfectant. The spores of anthrax are not killed by several 

 days' exposure to the liquefied gas. Anthrax and other bacilli 

 are destroyed in thirty minutes when exposed on moist threads 

 in an atmosphere containing one volume per centum of the gas. 

 An exposure of twenty-four hours in an atmosphere containing 

 four volumes per centum of the gas will destroy the organisms 

 of typhoid fever, diphtheria, cholera and tuberculosis. The 

 presence of moisture greatly enhances the activity of the disin- 

 fectant, owing to the formation of the more energetic sulphurous 

 acid. 



For the destruction of insects, such as mosquitoes, this agent 

 is superior to formaldehyde. Its application for this purpose is 

 important in preventing the spread of yellow fever and malaria. 



In practice, at least 3 pounds of sulphur per 1000 cubic feet 

 should be used, and moisture must be present. This latter re- 

 quirement can be fulfilled by evaporating several quarts of water 

 within the tightly closed room just prior to generating the gas. 

 In using powdered or flowers of sulphur, the necessary amount 

 is placed on a bed of sand or ashes in an iron pot, which should 

 rest on a couple of bricks in a pan or other vessel containing an 

 inch or two of water. The sulphur is ignited by means of some 

 glowing coals, or by moistening with alcohol and applying a 

 match. Difficulty is often experienced in keeping the sulphur 

 burning, and for this reason it is surer and more convenient to 

 use the so-called sulphur candles now on the market. In operating 

 with these, a sufficient number are placed on bricks in a pan of 

 water and the wicks lighted. Liquefied sulphur dioxide may be 

 used, and can now be obtained in convenient tin receptacles con- 

 taining a sufficient quantity for the disinfection of an ordinary 

 room. The can is opened by cutting through a soft metal tube 

 projecting from the top. The fluid vaporizes at the room tem- 

 perature, and it is simply necessary to place the can in a con- 

 venient porcelain dish and allow the fluid to evaporate. 



Sulphur dioxide is objectionable on account of its lack of 



