262 FUMIGATION METHODS 



nard, it remained for M. Cornu and M. Mouillefert, two 

 French investigators, to determine its real value in 

 this connection nearly twenty years later. They ex- 

 perimented upon many species of insects representing 

 various groups, paying particular attention to the 

 grape phylloxera, the most serious pest to the vine- 

 yards of France. They found that an atmosphere 

 containing one part of carbon bisulphid and nine parts 

 of air killed insects within a few seconds when con- 

 fined in the vapor ; and that one part in 254 parts of 

 air was also fatal in about one and one-quarter hours. 



The application of carbon bisulphid for the de- 

 struction of insects in mills, elevators, and other places 

 where large quantities of grain is stored is of recent 

 origin. Its extensive use to kill gophers, ground 

 squirrels, and other noxious subterranean and undesir- 

 able rodents is a comparatively new method. 



In the arts it is employed as a solvent of sulphur, 

 phosphorous, oils, resins, caoutchouc, gutta-percha, 

 etc. It is indispensable in the manufacture of rubber 

 and waterproof goods. In the manufacture of woolen 

 goods it is used to abstract oils and fats from the wool. 

 It is not considered an extra hazardous material, 

 otherwise it w r ould not be so extensively used. 



Work in France against Phylloxera. The treatment 

 of vines in France with carbon bisulphid for the 

 destruction of phylloxera is very extensive. Some 

 years more than a quarter of a million acres receive 

 treatment. Upon being introduced into the soil at some 

 depth below the surface the liquid evaporates as it 

 does in the open air, but much more slowly. The 

 vapor diffuses through the air spaces of the soil. It 



