158 MANUAL OF BACTERIOLOGY. 



The great interest which is taken by the public and by physi- 

 cians in the subject of pure milk has led some dairyman to 

 take steps to prevent contamination of the milk by cleanliness in 

 the barnyard and stable, and in careful cleansing of the udder? 

 of the cows, the hands of the milkers and the milk-cans. The 

 dairy-rooms are also kept scrupulously clean in the better 

 class of dairies, and the floors are kept wet to avoid dust* 

 The use of ice in cooling the milk as soon as it is drawn, and 

 in transportation is also used, and this serves to prevent the 

 multiplication of bacteria. In many dairies the cattle from 

 which the milk is obtained are regularly inspected at intervals 

 by veterinary surgeons as well as subjected periodically to the 

 tuberculin test. The surroundings and drainage of the stables 

 are investigated by physciians and sanitary engineers. The 

 milk is also regularly analyzed by a chemist and bacteriologist. 

 It has been found possible by such precautions to reduce the 

 number of bacteria in milk to a few thousands per cubic 

 centimeter or even much less. 



Other articles of food which are eaten after little or no cook- 

 ing such as salads, green vegetables, fruits, and the like, may 

 become, under exceptional circumstances, agents for conveying 

 infectious diseases. Conn showed that there was good reason 

 for attributing an epidemic of typhoid fever among students 

 at Middletown, Connecticut, to raw oysters. After having 

 been collected from the oyster-beds, these oysters were placed 

 in a small stream to fatten, where they were exposed to con- 

 tamination from a sewer. Into this sewer the discharges of a 

 case of typhoid fever were found to have been running at the 

 time when the oysters were fattening. An epidemic at Atlantic 

 City, New Jersey, in 1902, was traced to nearly similar causes 

 and conditions.! 



*W. H. Park. Journal o} Hygiene. Vol. I., 1901. 

 ^Philadelphia Medical Journal. November i, 1902. 



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