154 THE HOUSE FLY— DISEASE CARRIER 



a struggle between them and the prisoners for the 

 food. An active prisoner might possibly be able to 

 protect his plate from contact with them; but many 

 are careless and do not seem to mind much.'' Actual 

 experiments were made by exposing boiled milk; and 

 that exposed on the male side became infected with the 

 cholera germ. In conclusion, Macrae writes : 



"The practical lesson the experiments teach is, that 

 flies should be looked upon in the light of poisonous 

 agencies of the worst kind during cholera epidemics, 

 as it is clear that if they find access to poison they will 

 carry and distribute it, and every possible means should 

 be taken to prevent their getting into contact with either 

 food or drink of any kind, and to those having to deal 

 with large bodies of men it is a lesson more easily 

 learnt than put into practice." 



Another interesting instance of a somewhat similar 

 nature is cited by Nuttall and Jepson, in which they 

 state that W. T. Buchanan, in 1897, described a jail 

 epidemic which occurred at Burdwan in June, 1896. 

 This was also the case of a prison. Outside of the 

 prison there were some huts where cholera prevailed. 

 It is said that a strong wind blew great numbers of 

 flies from the side where these huts were into the prison 

 enclosure, where they settled on the food of the pris- 

 oners. It resulted that only those prisoners who were 

 fed at the jail enclosure nearest the huts came down 

 with cholera, while the others remained healthy. 



