722 
teid, fat, and milk-sugar which experience teaches us is suitable for 
the different ages of the child. 
We will now proceed to discuss wherein these principles are erro- 
neous. The error seems to be embodied in principle 4 and princi- 
ple 5. 
The fourth principle, i. e., that the casein of cow’s milk is indiges- 
tible, has been shown to rest upon a misconception. It only helps 
in a mechanical manner to produce indigestion when combined with 
large quantities of fat, or is altered in its digestive quality by fermen- 
tative changes in the milk at the time of consumption. 
It is the taking of the assumption of the indigestibility of the 
casein of cow’s milk for granted that has caused the rather numerous 
instances of overfeeding in the case of American children. In fact, 
under our present system overfeeding is apt to be the rule rather than 
the exception. By reason of the belief that the proteid of cow’s milk 
is the essential indigestible portion of its ingredients, it has been 
reduced, in the milk modifications prescribed by many of our physi- 
cians, almost to the point of extinction in certain individual cases. 
Kealizing, however, that food offered to a child must contain cer- 
tain elements of energy, the place of the proteid has been supplied 
by the use of fat, which, until in recent years, has been regarded 
digestible by many of our pediatrists and to act in conjunction with 
the carbo-hydrates as a proteid saver, besides promoting free action of 
the bowels. 
And yet what better proof that fat is the cause of constipation could 
be adduced than by the following circumstance wdiich Walls® has 
observed in so many instances, viz, that whenever the symptoms of 
fat intoxication are manifest, as evinced by the characteristic stools, 
a diet of fat-free whole milk works like a specific in initiating normal 
intestinal action. 
The fifth principle, going hand in hand with the fourth, is likewise 
erroneous in basing the composition of the milk modifications offered 
on the age alone of the child who receives them in so far as the 
weight of the child and the amount of the heat units necessary to 
nourish it and give it growth are not taken into proper consideration 
thereb}^ Moreover, only lately has the principle been recognized that 
food elements, if furnished even in trifling excess, instead of inuring 
to the benefit of the infant, have a way of reacting to his detriment. 
The following table, taken from a well-known text-book on pedi- 
atrics, can be used to further illustrate these points : 
®Loc. cit. 
