Again, the milk which is so generally considered as being fully equal to all the demands of the system, and especially so during the first few months of infant life, might be brought forward as proof positive and clearly illustrating the fact that nature calls for an excess of the CHO elements, because in the composition of the milk it is found that the CHO substances are about twice as abundant as the proteid or CHNOS elements. When these facts are examined a little more closely and scientifically, it is found that the pancreatic gland and its ferment-forming bodies are imperfecty developed at this period of life. Consequently, the fat, if emulsified and rendered capable of being absorbed by the lacteals of the villi, must have this transformation effected almost exclusively by the biliary fluid alone. It is further taught that the biliary secretion acts but little, if at all, upon vegetable fats and that it has the power to effectually emulsify only about one-half of the total quantity of animal fat introduced into the alimentary canal. This being true, fifty per cent, of the fat contained in the milk, together with the bile constantly flowing into the alimentary tract, is unquestionably utilized by the system as a natural laxative principle, and is undoubtedly the chief method by which nature effectually maintains the regular movements of the bowels and produces the daily evacuations so characteristic of a perfectly healthy infant. 

The proportionately larger size of the liver in a child as compared with an adult also points to the fundamental importance of the hepatic gland and its secretion as a necessary agent of prime importance in the infant; the large size of the liver compared with other organs also indicates its great importance during adult life. 

How much of the lactose — which is the form of sugar introduced in the milk — is inverted into glucose and rendered capable of being absorbed and utilized is an open question. In fact, there is no very reliable data upon this important point, but what is to be found upon the subject indicates quite positively that a considerable quantity of the lactose is not changed so as to be utilized by the system, but passes off with the faeces. Therefore, when the scientific truth is clearly appreciated, it is found that the relative proportion between the CHO and the CHNOS elements contained in the milk and that which can gain access to the vascular channels and be of service to the system is not far from equal in amount the major quantity, perhaps a little on the side of the CHO substances or in favor of the fat and sugar. Then, again, the infant requires a little more of the heat-producing compounds during the first few weeks or months than is needed a little later on or in adult life, because the proportionate amount of energy expended is greater in the infant and child than is the case during the adult period of life. Very early in the infant life there is comparatively little muscular action by which heat and energy can be evolved, while a large amount of heat is needed to maintain a perfect physiological condition, and for a time warmth must be artificially supplied. These conditions will admit of a little excess of the CHO elements during this period of life , but when the stage of infant muscular activity commences its never-ceasing motion, then the proportionate amount of the proteid substances must be raised and the CHO, or fat and sugar lowered, if the most perfect type of physiological development is to be effected. 

Observing clinical phenomena a little more closely, it is quite apparent, as life advances, that milk is not equal to the demands of the system, and a more strongly proteid diet is urgently called for by nature. Eggs and lean meat must next be added to furnish this much-needed proteid pabulum for the constructive purposes of the animal economy, and out of which alone the most perfect muscles, glands, ferment bodies, and brain tissue can be formed. 

By this process of reasoning, it is clearly and well established that even with the commonly supposed typical food-stuff, milk, it is not sufficiently perfect in its composition to thoroughly sustain the nutritive economy under all circumstances, but must have added to it a more liberal proteid pabulum. It is also clearly demonstrated that a portion of this excessive amount of fat is not taken up by the circulatory or lymphatic system but is used largely by nature as a laxative agent.

Proceeding a step further in the investigation of the clinical facts bearing upon this most interesting subject and there is found quite a common tendency among people at large to add to the nutritive supply of the infant not the most serviceable kind of food-stuffs in the way of an animal proteid of some kind, but on the contrary the more general practice is that of adding a cereal or vegetable compound, — one in which the CHO elements are very greatly in excess of the demands of nature. Another important point to be remembered in this connection is the well established fact that, although the proteid of vegetable origin, while in quite sufficient quantities, is a much higher nitrogenous compound and, as a rule, is far more difficult of digestion than a proteid body derived from the animal kingdom. 

By this method of infant feeding in which an excess of the fat, sugar, and starch or CHO compounds are used, a natural taste and habit of eating food derived largely from ficially supplied. These conditions will admit of a little excess of the CHO elements during this period of life , but when the stage of infant muscular activity commences its never-ceasing motion, then the proportionate amount of the proteid substances must be raised and the CHO, or fat and sugar lowered, if the most perfect type of physiological development is to be effected. Observing clinical phenomena a little more closely, it is quite apparent, as life advances, that milk is not equal to the demands of the system, and a more strongly proteid diet is urgently called for by nature. Eggs and lean meat must next be added to furnish this much-needed proteid pabulum for the constructive purposes of the animal economy, and out of which alone the most perfect muscles, glands, ferment bodies, and brain tissue can be formed. By this process of reasoning, it is clearly and well established that even with the commonly supposed typical food-stuff, milk, it is not sufficiently perfect in its composition to thoroughly sustain the nutritive economy under all circumstances, but must have added to it a more liberal proteid pabulum. It is also clearly demonstrated that a portion of this excessive amount of fat is not taken up by the circulatory or lymphatic system but is used largely by nature as a laxative agent. Proceeding a step further in the investigation of the clinical facts bearing upon this most interesting subject and there is found quite a common tendency among people at large to add to the nutritive supply of the infant not the most serviceable kind of food-stuffs in the way of an animal proteid of some kind, but on the contrary the more general practice is that of adding a cereal or vegetable compound, — one in which the CHO elements are very greatly in excess of the demands of nature. Another important point to be remembered in this connection is the well established fact that, although the proteid of vegetable origin, while in quite sufficient quantities, is a much higher nitrogenous compound and, as a rule, is far more difficult of digestion than a proteid body derived from the animal kingdom. By this method of infant feeding in which an excess of the fat, sugar, and starch or CHO compounds are used, a natural taste and habit of eating food derived largely from the vegetable kingdom is engendered. The natural sequence is, that on through life the individual is apt to continue eating excessively of all kinds of food-stuffs and particularly those of the CHO and vegetable class. This poorly nourishes the body; adipose tissue in abundance is often acquired from the imperfectly transformed foodproducts. The appetite increases because the system is not properly sustained. The individual continues eating more and more until finally the marginal capacity of the system for supplying oxygen is reached and passed, digestion is imperfectly effected, and the oxidization powers of the body exceeded.