THE SANITARY FACTORS 117 



while the situation had intensified; milk-borne disease 

 became more and more insistent; a new factor had 

 arisen in the shape of commercial pasteurization; the 

 necessity of public control became more pressing. 

 To-day the problem is how to exert such control in 

 a way which is scientific, just to all parties concerned, 

 equal to sanitary needs, yet economically practicable. 



Progressive sanitary authorities have recognized the 

 fallacy of attempting to make all market milks conform 

 to the same standard by lumping Together raw and pas- 

 teurized milks, milks for infant feeding and milks for 

 ordinary household use. Distinctions must be made. 

 The result has been the establishment of grades of milk 

 publicly distinguished by means of simple labelling. 



Such classification must logically be based on the 

 uses to which milk is put and the corresponding sanitary 

 criteria. The simplest division of uses is: (1) milk for 

 infants, (2) milk for adults, (3) milk for cooking and 

 manufacturing only. This requires three corresponding 

 grades. The conspicuous criteria are bacteriological 

 character and the application or non-application of 

 pasteurization. It is essential that the grades be few, 

 clearly defined, and readily understood. 



The idea of milk classification is not new. A rudi- 

 ment of it exists in the setting-aside of the special grade 

 of certified milk, which, however, has never played .a 

 quantitively important part in general milk supplies. 

 Dr. Ernest Lederle, then Health Commissioner of New 

 York City, advocated as long ago as 1907 the grading 

 of milks in some such manner as has since been effected 

 in that city. Dr. A. D. Melvin, Chief of the Bureau 

 of Animal Industry, United States Department of 



