SANITARY WATER SUPPLIES FOR DAIRY FARMS. 
By B. Meade Bolton, M. D., 
Biochemic Division, Bureau of Animal Industry, Department of Agriculture. 
The importance of sanitary water supplies 'for farms is not con- 
fined to the farmer himself and his immediate family, but it extends 
to the whole public. All products of the farm with which water 
comes in contact may be rendered dangerous to health by polluted 
water. All fruits and vegetables and receptacles used for collecting 
and shipping food and the hands of those who collect and pack farm 
produce may be infected by washing in impure water. The infec- 
tion in this case arises from the bacteria contained in the water, and 
after the bacteria are once conveyed to the food they increase very 
rapidly under conditions favorable to them. Many kinds of food 
furnish a favorable soil for the growth of bacteria, and this is par- 
ticularly the case with milk. Milk constitutes in fact one of the very 
best media for the development of many kinds of bacteria. Even 
with great care and cleanliness in milking, the bacteria which get 
into the milk quickly multiply to many thousands, unless the milk 
is kept cold. Bacterial contamination of milk arises not only from 
dust, hair, and filth at milking, but also comes from polluted water 
used by milkers for washing the hands, the udders, the milk pails 
and cans. The drops remaining in the can after rinsing with impure 
water are sufficient to contaminate all the milk put into the can, and 
the bacteria introduced into the milk in this way multiply rapidly, 
unless the milk is kept very cold. The danger from polluted milk is 
not only that there may be microbes present which may cause special 
diseases, such as typhoid fever and scarlet fever, but also that many 
bacteria cause changes in the milk which make it injurious to health, 
particularly injurious to children. In this case the bacteria them- 
selves may be of such a kind as not to produce disease if taken into the 
stomach alone, but they may nevertheless change the milk so as to 
make it to all intents a poison. 
The same thing is true more or less with all food, particularly with 
food which is eaten raw, but it is especially the case with milk. 
It may not be out of place to correct an erroneous idea which 
seems quite prevalent in regard to milk contamination through 
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