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in destroying its breeding places, and secondarily in the use of fly-traps, 

 fly-paper, etc. In towns and cities this is comparatively easy; on the 

 farm it is far more difficult. The screening of privies and cesspools, 

 and the close covering of garbage cans is generally not difficult. 



It is the handling of manure, particularly horse manure, that 

 is difficult. In cities it is comparatively easy to compel owners of 

 private and livery stables to keep all manure in closely covered bins 

 so that flies cannot gain access to it; but on the farm this is far more 



PIG. 74. Maggot trap for control of house-flies, showing the concrete basin 

 of water in which the larvae are drowned, and wooden platform on which the manure 

 is piled. (From Howard, House-Flies, after Hutchinson.) 



difficult. If not practicable to keep it in bins the manure should either 

 be spread on the fields every day or two where it will dry and kill the 

 fly eggs and larvae, or it must be sprinkled with some substance that will 

 kill the flies without injuring the manure; various chemicals have been 

 tried for this purpose with the conclusion that powdered hellebore 

 (using 3/2 lb. to 10 gallons of water for each 8 bushels of manure) is the 

 best substance, though its cost, about 0.69 cents per bushel of manure, 

 makes it fairly expensive. Perhaps the best, and in the end the cheap- 

 est, solution of the problem is to build a " maggot trap" to hold the 



