CHAPTER V 



IT must not for one moment be assumed that House Flies 

 are only capable of carrying the microbes of diseases within 

 a very restricted area. Flies may be carried two or three 

 miles bya high wind, and they have frequently been observed 

 to travel a mile and more on a calm day. That they fly 

 from house to house, and often over a wide area, has been 

 satisfactorily proved by careful experimentation. Flies 

 were captured and dipped into a certain chemical solution 

 and released. Then after the lapse of a day or two, flies 

 were collected in various neighbouring localities. These 

 were dipped in another solution, which had the property 

 of turning the flies previously dipped a brilliant blue. It 

 was in this way demonstrated that flies travelled consider- 

 able distances. 



In towns, flies are transferred from one locality to another 

 by various vehicles, domestic animals, &c., to which they 

 cling, or which they persistently follow, attracted by some 

 appetising odour. 



When there is sickness in a house, those responsible 

 should make every possible effort to free the dwelling of 

 flies, because at such times they are especially dangerous, 

 for they not only carry the microbes all over the house and 

 on to foodstuffs, but they are also likely to carry them to 

 neighbours' houses. 



Therefore, knowing that flies are the principal agents in 



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