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AGRICULTURAL BACTERIOLOGY 



Fig. 36. Typhoid Fever Spread by Milk (Stamford, Conn.) 

 The small squares represent milk producers and dealers and the lines milk 

 routes in a village. Three hundred and eighty-six cases of typhoid fever 

 occurred on one route and but eighteen on the routes of the other nine 



distributors 



organism is unable to grow in water, the bacilli gradually 

 die, and within a week or ten days all have perished. 



Contamination of water supplies. The most frequent 

 manner in which water is contaminated is by its pollution 



