USE OF GASES AGAINST HOUSEHOLD INSECTS 455 



cable, it would be best to place the material to be 

 fumigated in a tight box or barrel. In any case, two 

 or three pounds of the carbon bisulfide should be used 

 to every one thousand cubic feet of space. The fumiga- 

 tion should extend over a period of at least forty-eight 

 hours and the temperature should be from 65 to 75 degrees 

 F. The larger the surface of the liquid there is exposed 

 to the air the quicker it will evaporate and the greater 

 volume of gas there will be in the room at a given time. 

 Therefore, the liquid should be exposed in wide shallow 

 pans or poured directly upon the material. 



One of the most convenient ways to fumigate peas, 

 beans, corn, or similar seeds is to place them in a tight 

 box or barrel and fill the receptacle to within eight or 

 ten inches of the top. The requisite amount of carbon 

 bisulfide should then be poured into a wide shallow pan 

 and set on top of the seed. As quickly as possible the top 

 should be covered air-tight. Perhaps several thicknesses 

 of newspapers or building paper with thick blankets over 

 these would make the opening tight. The fumigation 

 should be allowed to extend over a period of forty-eight 

 hours at least and no fire in any form should be brought 

 near the receptacle until it has been opened and well 

 aired. 



SULFUR 



The fumes of burning sulfur, sulfur dioxide, have 

 long been used as a disinfectant and insecticide ; but since 

 the fight against the malarial and yellow fever mosquitoes 

 this gas has assumed an added importance. It is used 

 almost entirely by city health boards, physicians, and 

 investigators in fumigating rooms and buildings to destroy 



