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of infantile or summer diarrhcea and typhoid fever. It is, 
therefore, of prime importance to give the Insect no oppor- 
tunities for breeding and thereby providing a check upon 
its abundance. All accumulations of manure and refuse 
should be removed uz least once a fortnight, or more often 
if possible. “he adoption of closed ash-bins excludes the 
access of the Flies to their contents, and are most effective 
in this respect. | Accumulations of farm manure provide 
nutriment for enormous numbers of House Fly maggots. 
Experiments on a large scale are being conducted both in’ 
this country and America for the purpose of rendering 
manure heaps repellant to the Flies and their maggots 
and, at the same time, still retaining their valuable fer- 
tilising properties. When troublesome in houses the House 
Fly can be readily poisoned by using one teaspoonful of 
formalin added to a teacupful of water poured into a 
soup plate. The mixture should be sweetened with a little 
sugar or should contain about 25 per cent. of milk. If 
placed at night large numbers of the Flies will partake 
of it in the early morning and are poisoned thereby. The 
mixture also has the advantage of being too weak to be 
harmful to human beings or domestic animals. 
