FOODS — HUMAN NUTEITION. 461 



vious edition, and Is designed to bring tlie subject-matter into accord with the 

 results of recent clinical and experimental observations. It discusses the 

 chemical and physiological aspects of the various constituents of infant diet 

 during metabolism, including energy transformations ; the physiological de- 

 velopment of normal infants; the nutrition of breast-fed infants, and their 

 nutritional disorders ; artificial feeding ; mixed feeding and weaning ; feeding 

 the newly born and the prematurely born ; and the various diseases to which 

 infants are liable. There is included a table showing the energj^ value per 100 

 gm. of the more important types of natural and modified milli and milk substi- 

 tutes commonly prescribed by German physicians. 



A chemical study of woman's milk, especially its inorganic constituents, 

 L. E. Holt, Angelia M. Courtney, and Helen L. Fales {Amer. J our. Diseases 

 Children, 10 {1915), No. 4, pp. 229-248) .—The authors report the results of an 

 investigation of the composition of the ash in woman's milk at the different 

 periods of lactation. In most cases the entire 24 hours' secretion was ex- 

 amined ; 32 individual samples and 6 composite samples — all from apparently 

 healthy women with healthy children — were taken. The conclusions are sum- 

 marized as follows : 



" The use of large individual samples of milk for analyses has advantages 

 not offered by such small ones as have been commonly employed. For a de- 

 termination of the inorganic constituents large samples are indispensable. 



" In the colostrum period woman's milk has high protein and high ash with 

 rather low fat; in the transition period the protein and ash are lower while 

 the fat Is higher; in the mature period (after one month) the composition of 

 normal milk does not vary in any essential or constant way quite up to the 

 end of lactation. The only striking feature of late milk is a decline in quantity, 

 though there is noted a slight fall in all the solid constituents except the sugar. 



" Of the different constituents of milk the least variation both in individuals 

 and in periods is seen in the sugar. The proportion of this is somewhat higher 

 than the generally accepted 7 per cent; 7.5 per cent is nearer the correct figure. 



"The greatest individual variations are seen in the fat, though the period 

 variations in fat are not marked. 



"The protein is highest in the colostrum period and falls to a little over 

 half the proportion in mature milk, during which period it is seldom over 1.25 

 per cent ; of this about one-third is casein, and two-thirds laetalbumin. 



" The high ash of the colostrum period Is chiefly due to the amount of NajO 

 and K2O. Of the salts which make up the ash, the greatest individual, as 

 well as the greatest period, variations are seen in the NaaO; the least Individ- 

 ual and period variations are seen in the CaO, the proportion of which is 

 nearly constant throughout the period of lactation. The largest constituent 

 of the ash of woman's milk is K2O; this with the CaO together make up more 

 than half the total ash. 



" Although In amount the total ash of cow's milk is about three and one-half 

 times as great as that of woman's milk, the proportion of different salts which 

 make up the ash Is nearly the same, the only exception being that cow's milk 

 has more P2O5 and less iron." 



Studies in infant metabolism and nutrition. — V, The composition and 

 preparation of protein milk (Eiweissmilch), L. E. Holt, D. D. Van Slyke, 

 Angelia M. Courtney, and Helen L. Fales (Amer. Jour. Diseases Children, 10 

 {1915), No. 3, pp. 172-lS2).—This report describes In detail a method for the 

 preparation of a protein milk which has given very satisfactory results in 

 cases of infantile indigestion. The composition of the milk when prepared ac- 

 cording to the method described by the authors is given as fat, 3 to 3.5 per 

 cent ; sugar, 1.8 to 2 ; protein, 3.6 to 4 ; ash, 0.65. 



