FOODS HUMAN NUTRITION. 69 



cal use to the housekeeper in arrauging a diet which is in reasonable accord 

 with dietary standards, due regard being paid to cost and to character of 

 materials. 



Feeding experiments with isolated food substances, T. B. Osbokne, L. B. 

 Mendel, and Edna L. Febby {Carnegie Inst. Washington Pub. 156, pt. 2 {1911), 

 pp. 111+55-138, pis. 2, figs. 108). — Continuing work previously noted (E. S. R., 

 25, p. 864), the authors report investigations of the nutrition factors which 

 influence growth. In the experimental data cited laboratory animals (rats) 

 were used. 



Especial attention is paid to such problems as the suspension of growth on a 

 maintenance diet, the effect of stunting on the growth impulse, the effect of 

 partial starvation on body weight and on the nervous system, a comparison of 

 milk and mixed diet, and a study of isolated proteins and " protein-free " milk. 

 Conclusions from the authors' discussion of the results presented and their 

 bearings follow : 



"A comparison of the two groups of proteins — those adequate and those 

 inadequate for growth purposes — at once reveals the fact that the latter cate- 

 gory comprises proteins (gliadin, hordein, zein) commonly spoken of as chemi- 

 cally ' incomplete.' They lack one or more of the amino acid complexes which 

 are obtainable from the so-called * complete ' proteins. >Cone of them furnish 

 glycocoll or lysin, and zein in addition is devoid of tryptophane. By feeding 

 relatively small quantities of proteins like casein with gliadin growth begins 

 at once. Here we can determine the minimum of suitable protein to satisfy 

 this growth requirement. . . . The addition of amino acids to ' complete,' 

 as it were, the inadequate proteins can now be studied amid controllable 

 factors; the biological role of hydrolyzed proteins and the significance of com- 

 plete hydrolysis or digestion in nutrition can be examined anew. 



"The experiences which have demonstrated the striking differences in value 

 of the individual proteins and the small proportion of casein which suflices to 

 induce growth instead of standstill . . . emphasize the importance of the 

 purity of the protein fed. . . . 



" The animals must here have synthesized their phosphorous compounds 

 from inorganic phosphorus. Whether milk production and other functions call- 

 ing for such synthetic reactions will continue adequately is open to investi- 

 gation. It is also noteworthy that all of our animals grow on a dietary that 

 is purin-free, or essentially so. Here the question of purin sybthesis suggests 

 itself. It is apparent, e. g., in the case of gliadin, that the grown as well as 

 uugrown rats may be maintained for long periods on single proteins. 



" With such an ideal nonprotein dietary component at hand amino acid sub- 

 stitutions can be attempted in the adult as well as in the growing animal. The 

 protein minimum (or minima) is also open to accurate investigation. With a 

 method of feeding devised which will permit a differentiation between growth 

 and maintenance, which furnishes an energy-yielding protein-free component 

 that is appropriate, and leaves the protein as the sole variable in the dietary, 

 we believe that further contributions can be made to the problems of nutrition." 



Influencing the bone growth by food poor in phosphorus, G. Schmobl 

 {Arch. Expt. Path. it. Phannahol., 13 {1913), No. 4, pp. 313-3Jt6, fig. 1; ahs. in 

 Chem. Zentbl., 1913, II, No. 21, pp. 1813, 1814).— In experiments with labora- 

 tory animals (dogs) it was found that food poor in phosphorus resulted in a 

 diminished production of bone substance. 



Experiments bearing on the functions of the liver in the metabolism of 

 fats, I, H. S. Rapee {Jour. Biol. Chem., 14 {1913), No. 2, pp. 117-134).— In this, 

 the first of his studies of the digestion and absorption of fat, the author reports 



