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and immediately treat them with carbon bisulphide. Within a period 

 of seven years, about thirty different treatments of peas were made in 

 the Experimental Department for the destruction of the pea weevil. 

 In handling the crop, care was taken throughout to pull the peas at 

 the proper time, to haul them to the barn when dry, and to thresh them 

 as soon as possible. Immediately after threshing, the peas were put 

 into cotton or jute bags. As soon as thirty bushels of peas were 

 threshed, they were placed in a fumigation box for treatment. One 

 pound of carbon bisulphide was poured into three flat pans, which were 

 placed on the top of the peas ; the cover was then put on the box and 

 weighted with heavy stones. After forty-eight hours the cover was 

 removed and the box ventilated. The pans had become dry, as the 

 liquid had changed into a gas, which, being much heavier than air, had 

 sunk down amongst the peas penetrating them and killing the weevils. 

 The quantity of carbon bisulphide used by us was larger than that 

 usually recommended, as a pound or a pound and a half is generally 

 considered sufficient for one hundred bushels of peas, but we wished 

 to be on the safe side. In practically all cases the weevils were des- 

 troyed at the first treatment, no matter whether they were in the larva 

 form, in the pupa stage, or had become fully developed. The treat- 

 ment can be made in any comparatively air-tight receptacle, whether 

 a barrel, box, or specially made fumigation house. 



Carbon bisulphide is a colorless or slightly yellowish liquid, one- 

 fourth heavier than water. It is extremely volatile, i. e., it evaporates 

 very rapidly when exposed to the air, and when pure will not injure 

 or stain the finest goods' The commercial liquid has an acrid taste,, 

 and an odor like that of rotten eggs. The vapor is more than two 

 and a half times as heavy as air. Carbon bisulphide may be purchased 

 in small quantities from any druggist at about 30 cents per pound, or 

 40 cents per pint. For large quantities, better rates can be given by 

 the druggist. The gas, or vapor, which comes from carbon bisulphide 

 is not only combustible, but it is very explosive when mixed with air. 

 Great care should therefore be taken to treat the peas in the daytime 

 only, for a light or a flame of any kind brought near the liquid may 

 cause a serious explosion ; and smoking near it should be positively 

 prohibited. Moreover, the vapor should not be inhaled, as it is very 

 injurious, even a small portion causing headache, giddiness, and nau- 

 sea. The treatment with carbon bisulphide should be made in boxes, 

 barrels, or "bug houses," located some distance from the insured build- 

 ings on the farm. 



With the strict observance of the preceding precautions, no one 

 should hesitate to use the carbon bisulphide. As a matter of fact, we 

 have never heard of any bad results following its use in the treatment 

 of peas. This happy condition of things may be explained when we 

 say that all who used the liquid were wise enough to be cautious. There 

 is, moreover, no danger that the vapor will injure the peas or render 

 them unsafe as a food. Experiments have shown that the liquid can 



