644 
As the milk drawn from the breast during the first part of nursing 
is richer in proteids and much poorer in fats and the last portion 
rather poorer in proteids and rich in fats, the entire amount of milk 
present in the breast should be drawn off for the purpose of this esti- 
mation. 
cow’s MILK. 
Cow’s milk is the only food supply apart from mother’s milk avail- 
able in this country, from a practical standpoint, for the nourishment 
of infants under 1 year of age. It forms besides a large part of the 
dietary of older children and of many adults. It is consequently of 
the utmost importance, in view of its perishability, that it should 
only be used as a food under conditions which will insure its whole- 
someness. 
We have already considered the enormous loss of life occurring 
among the artificially fed infants, of which the larger part is un- 
doubtedly due to bad milk and its imp roper use as an article of diet. 
Stated as a general proposition, the folloiving conditions should be 
fulfilled in milk that is to be used as a basis for the nourishment of 
young infants: First, it should be' clean; second, it should be fresh; 
third, it should be whole (i. e., not falsified by additions or subtrac- 
tions of its component parts or by the addition of preservatives) ; 
fourth, it should be free from pathogenic organisms and toxic prod- 
ucts; and, fifth, it should be kept cold. 
Importance of clean milk . — By clean milk we understand a milk 
which has been collected under such hygienic conditions from healthy 
animals and handled under such proper precautions as to insure its 
reaching the consumer without containing any visible particles of ex- 
traneous matter as well as any excessive number of bacteria. 
Unfortunately, whenever the milk supply of a community has been 
investigated, either under public or private auspices, the conditions 
found to prevail in the production and handling of milk have always 
been disappointing if not, as in many instances, revolting to the last 
degree. The insanitary surroundings and general condition of filth 
prevailing at some dairy farms is at times indescribable, and the ex- 
amination of milk produced under these conditions reveals not only 
a bacterial flora, but a degree of contamination with gross particles 
of extraneous matter such as to suggest utter carelessness or ignor- 
ance on the part of the producer. 
Milk when produced under such circumstances not only contains a 
plentiful enrichment of dust, dirt, dung, cow hairs, flies, and other 
foreign bodies, but also a bounteous inoculation of bacteria of all 
forms, such as may render it from the very outset unfit for human 
consumption. 
