72 BACTERIOLOGY 



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

 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 con- 

 taining four volumes per centunj of the gas will destroy the organ- 

 isms of typhoid fever, diptheria, 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 appljdng a 

 match. Difl&culty 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. 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 

 be obtained in convenient tin receptacles containing 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 temperature, and it is 

 simply necessary to place the can in a convenient porcelain dish 

 and allow the fluid to evaporate. 



Sulphur dioxide is objectionable on account of its lack of 

 germicidal power when dry, and on account of its corrosive action 

 on metal and its bleaching effect on hangings and draperies in the 



