INSECT CONTROL IN FLOUR MILLS. 



19 



Sacks. — Sacks for holding the individual charges of cyanid are 

 needed. When 4-gallon crocks are used common manila paper 

 sacks, sizes 8 and 10, such as may be had of any grocer, are the best 



Fig. 11. — Fourth floor of a flour mill, showing the proper arrangement of the 

 generators and the bags of cyanid for hydrocyanic-acid gas fumigation where 

 the bags are to be dropped by hand. (Dean.) 



in which to place the cyanid. The cyanid is placed in the smaller 

 sack, after which the smaller sack is slipped within the larger one. 

 Sacks of heavy or heavily glazed paper should not be used, for 



