966 EXPERIMENT STATION RECORD. 



0.1788 oc. the averajre beiujr (•.ir>T4 cc, and iu 18 out of 26 specimens of human 

 milk, in which the allialiuity of the ash was determined, it ranjied from 0.1196 

 to 0.1Ti>n c-c. of tenth-normal sodium hydroxid. the average l)e!ng 0.1513 cc, 

 which numbers agree reasonably well with the average alkalinity of the ash 

 of the two kinds of milk calculatetl from the complete analyses. 



'• It is evident, therefoi-e, that while cow's milk contains from 2.5 to 3.5 

 times as much mineral matter as human milk, the ash of the two milks contains 

 approximately the same amount of available alkali. . . . The salient points 

 of difiference between the two kinds of milk are: Human milk contains rela- 

 tively more of its mineral matter iu utilizable form than cow's milk; it can 

 supply the organism of the child with relatively larger amounts of available 

 alkali in proportion to the proteid than cow's milk; it contains much less 

 proteid ; and it contains a more readily absorbable variety of fat. ... It is 

 believed, therefore, that while the primary cause of gastro-iutestinal dis- 

 turbances following the use of cow's milk in infant feeding is due to the fact 

 that the fat is not readily absorbed, the more remote and fundamental cause 

 of these disorders iu infants fed upon rich cow's milk is an excessive proteid 

 metabolism and an insufficiency in available mineral matter in cow's milk as 

 compareil with human milk. . . . Some of the most valuable reconmiendations 

 and practices relating to infant feeding, such as the feeding of skim milk and 

 buttermilk, the addition of certain alkaline substances to the diet such as 

 citrates, the dilution of cow's milk with barley broth, etc., or with water con- 

 taining the white of egg as recommended by Lehmann, and the use of such 

 substances as orange juice, as adjuncts to the infant diet, are in accord with 

 the ideas herein set forth. Practically all of these aids to artificial infant 

 feeding, based as they are uiwn the results of sound practical experience, have 

 for their object either the reduction of the amount of fat In the milk or the 

 addition thereto of mineral matter available for the neutralization of acids 

 resulting from metabolism, or both. In this connec-tion it is interesting to 

 note that the ash of white of egg and orange juice both contain considerably 

 more available alkali than cow's milk." 



Tables of the alkalinity and the ash contents of milk are given. 



Nutrition processes during the growth, of the child, M. Rubneb (Arch. 

 Hijfj.. 06 ilUOS). .Yo. 1-2. PI). Sl-126). — In this theoretical discussion of diet 

 during the period of growth the author emphasizes the importance of energy 

 considerations and gives reasons for his belief that the proteid retiuirement has 

 been sometimes overestimatetl. The article is a very important contribution to 

 the the<iry of infant feeding. 



Theory of nutrition after completion of growth, M. Rubneb (Arch. Hyg., 

 66 (190S), Xo. 1-2. pp. ISO). — This di-scussion of theories of nutrition is chiefly 

 concerned with protein metabolism, and considers the functions of body protein, 

 stored protein, protein as building material and protein as a source of energy, 

 and related topics. Protein metabolism, the author states, varies according to 

 the protein requirements of the cell, the cell with little protein retaining more of 

 the protein supplied to it than one which is rich in this constituent. For this 

 reason a large protein supply does not cause so great nitrogen excretion in the 

 former case as in the latter. 



The author discusses nitrogen metabolism and gain on a basis of the amount 

 of nitrogen present in the body rather than on the usual basis of body weight. 

 Cell function is the primary consideration in protein metabolism. The cleavage 

 of protein accommodates itself to this factor, and there is a relationship be- 

 tween cell function and the size of the body. Within certain limits nitrogen 

 metabolism is more rapid the more protein is supplied. 



