30 THE HOUSE FLY 



a single fly is capable of infecting a jug of milk with a million 

 microbes of any infectious disease from which mankind 

 suffers. Nothing short of boiling for, sometimes, as long as 

 fifteen minutes, will destroy the germs of disease with 

 which any fluid, such as milk, might become infected after 

 a fly falls into it. The usual custom is simply to remove 

 the flies and use the fluid. It is an everyday occurrence 

 for a couple of love-making flies to drop into a cup of tea 

 or coffee, and to see them removed with a teaspoon and the 

 fluid imbibed. 



It is anything but a pleasant thought to think that when 

 taking your soup, a cup of milk, tea, coffee or other fluid, 

 you are at the same time taking a dose of a million of more 

 of the germs of enteric fever. It is indeed fortunate for 

 us that the stomach and intestines, when in health, secrete 

 fluids which are strongly antiseptic, otherwise the human 

 race would long since have been extinct. 



A plate was taken by an experimenter and covered with 

 a thin layer of gelatine. A fly was captured at random, and 

 after clipping its wings it was allowed to walk across the 

 plate. On subsequent examination it was discovered that 

 a colony of disease germs had grown wherever the fly had 

 touched the gelatine with its feet. 



It has been found that the spores of a fungus which 

 attacks sugar cane is carried on the feet of House Flies ; 

 therefore this fly is not only a danger to man and animals, 

 but to plants as well. 



Now, these facts are more important than they may seem. 

 It means that flies can and do transfer the microbes of 

 various diseases from the slums to healthy sanitary homes, 

 and from sick people or animals in one part of the town to 



