THE MILK SUPPLY OF CITIES. 633 



freelv, looking upon the danger as a slight one and one of the un- 

 avoidable dangers of living, but if such advice is given some one 

 will instantly declare it bad advice. It might be possible to advise 

 boiling all milk before drinking, and again some authority would 

 say that this is unnecessary and bad. Personally, the author, 

 though living in a small community, uses raw milk with perfect 

 freedom, but would regard it as unwise to allow young children, 

 especially infants, to use it in this way. 



As already stated, the agitation over the milk supply is greater 

 in Europe than in this country. While in England milk is used 

 much as in this country, on the continent really little milk is drunk 

 raw, and there is a growing demand for some means which shall 

 deprive milk of the suspicions attached to it. This demand has 

 been rapidly growing in recent years, and has resulted in the ap- 

 pearance of two new industries. These are the preparation of 

 sterilized and Pasteurized milk. Neither of these industries has as 

 yet developed much in the United States, although in our larger 

 cities beginnings are being made along similar lines. 



Sterilized milk has been used for many years. Long ago our 

 doctors learned to recommend, for invalids, that milk should be 

 boiled before drinking. This was done before ihe matter of its 

 relation to bacteria was understood, and when physicians simply 

 conceived that the boiling rendered the milk more digestible. 

 From being used by invalids it came to be suggested in feeding in- 

 fants, and then, after the relation of milk to possible disease germs 

 had been understood, the general sterilization of milk was widely 

 recommended. The process of sterilization of milk has not taken 

 much of a hold upon the people of this country as yet, nor has it 

 in England. In continental Europe, especially in northern coun- 

 tries, where the amount of tuberculosis is very large, it has made 

 rapid headway, and now in most of the cities sterilized milk can be 

 bought on the streets just as easily as ordinary milk. 



In sterilizing milk as it is done in Europe the destruction of 

 the disease germs is not the only purpose. An object of perhaps 

 equal weight is to produce a milk that will keep. There are many 

 circumstances where it is desirable to carry milk for long distances, 

 and to lay in a supply to last many days or even weeks. Under 

 these circumstances sterilization is resorted to, since it preserves 

 the milk. 



There are various methods of sterilizing milk. The simplest, 

 and doubtless the most common, is simply the boiling of the milk. 

 This can easily be done by any one at home, and is, beyond question, 

 very widely resorted to. But where the sterilization is to be per- 

 formed by a public-supply company, boiling is not satisfactory, since 



