No. 4.] MILK SUPPLY AND PUBLIC HEALTH. 49 



cities. In this case the milk is no longer strictly normal. 

 Between the producer (the cow) and the consumer (the indi- 

 vidual who swallows the milk) have come in one or more 

 middlemen, — the milker, the housewife, the housemaid, it 

 may be. Moreover, the milk has been more or less exposed 

 to air, possibly dust-laden and always carrying microscopic 

 germs of fermentation; to vessels — pails, pans, strainers — 

 often richly seeded with similar microscopic organisms ; and 

 time has elapsed, longer or shorter, so that these organisms 

 have, slightly or extensively, as the case may be, caused the 

 milk to ' ' work " or ferment. This in itself marks a departure, 

 often trifling but always real, from the absolutely normal 

 milk supply, such as calves and infants naturally enjoy. 

 The sources of danger here are much increased, for it is no 

 longer merely the question of a healthy, well-fed parent as 

 producer ; we have also to consider now a possible contami- 

 nation by the milker, the housewife or other "middleman" 

 before the milk enters the stomach of the consumer, and also 

 those natural alterations which it undergoes after being seeded 

 with the germs of fermentation during the time which elapses 

 between its exit from the teat of the cow and its entrance into 

 the mouth of the real consumer. In well-regulated families, 

 however, the risk of damage so resulting is from a sanitary 

 point of view comparatively slight, and they are fortunate 

 who may enjoy the privilege of possessing a milk supply of 

 this simple primitive kind. 



Not by any means the least important fact in this domestic 

 system of supply is the possibility of complete personal ac- 

 quaintance on the part of the consumer with the sources of 

 his supply, and a consequent control over them. This, as 

 we shall see, he almost unconditionally surrenders when he 

 becomes an ordinary dweller in a great city. 



Village or Suburban Milk. — As men come to live in larger 

 villages and towns, some give up the keeping of cows and 

 buy of their neighbors who, in order to supply them, keep 

 more cows. The personal acquaintance of the consumer with 

 the exact sources of his supply diminishes, and his personal 

 control is relaxed somewhat ; but he still keeps up a general 

 knowledge and supervision, and may, if he chooses, know 

 and do more at any time. But, as the neighbor who s,\\\>- 



