INSECT CONTROL 



335 



from 20 to 36, and the corresponding specific-gravity 

 reading. 



Dilution table for concentrated lime-sulphur solutions. 1 



1 From Farmers' Bulletin 650, U. S. Dept. Agriculture. 



3. Gases. Carbon Bisulphide is extensively used against 

 insects affecting stored goods and grains, and for root-feeding 

 insects. It is a clear, volatile liquid giving off fumes heavier 

 than air. It may be thrown directly onto grain without 

 injury to it or placed in shallow dishes. For grain in store 

 in fairly tight rooms apply five to eight pounds to eveiy 100 

 bushels, distributing the bisulphide over the surface or in pans 

 containing not over one-half of one pound each. Make the 

 enclosure as tight as possible, covering the grain with blankets 

 or other tight cover, if necessary, and leave for twenty-four 

 hours. Recent experiments have shown that the vapor is 



