34 THE MODERN MILK PROBLEM 



bulletin concludes a discussion of milk supply with 

 the words, "The choice is easy. Insist upon clean, 

 pure milk." Everyone familiar with the subject has 

 heard or read that sentiment hundreds of times. The 

 phrase "pure milk" suggests its opposite, "impure 

 milk," and it is a common popular idea derived from 

 these terms that there are two clearly distract kinds 

 of milk, good milk and bad milk. Many people doubt- 

 less believe that an inspector can thrust a tester into a 

 can of milk and decide instantly in which category it 

 belongs. The usual demand for "pure milk" is a de- 

 mand for the best milk, and the notion is that one such 

 best can be both denned and universally obtained. 

 "The chief good to be accomplished at the outset," 

 writes a newspaper in comment upon a milk campaign, 

 "will be the arousing of public sentiment against any- 

 thing but the purest milk." 



The trouble with this is that it requires an absolute 

 ideal incompatible with practical conditions. Bac- 

 teria in milk are impurities, but it should be recognized 

 that a certain bacterial content must practically be 

 permitted according to the purpose for which the 

 product is to be used. Again, there are varying nat- 

 ural degrees of nutritional value, and science has not 

 determined exactly what is the most nutritive milk. 



The air would be cleared if we spoke of milks, thus 

 emphasizing their differing characters. The scientific 

 object is to gauge the qualities of milk of different 

 characters and reduce them to categories. When this 

 is done it is seen that instead of speaking of one ab- 

 solute kind of pure milk, it is logical to define what 

 shall be considered a "pure milk" for infants, or for 



