FOODS HUMAN NUTRITION. 665 



According to the author's conclusions, i)roteln contains 4 or 5 per cent (esti- 

 mated as hippuric acid) of a benzol constituent which is not hydrolized. In the 

 case of carnivorous animals the benzol ring is largely destroyed, while in the 

 case of herbivorous animals this is not the case, two-fifths appearing in the 

 urine as hippuric acid and three-fifths as phenazeturic acid. Accordingly, the 

 author concludes that this portion of the profeid molecule is 4 or 5 per cent less 

 valuable for herbivorous than for carnivorous animals. Phenazeturic acid he 

 regards as almost as important a constituent of the urine of herbivorous ani- 

 mals as hippuric acid. 



Quantitative investigations in regard to the elimination of protein acids 

 by the urine, W. Gakinski {Bid. Ititcrnat. Acad, Sci. Cracovic, CI. Sci. Math. 

 ct Nat., 1009, No. 9, vp. 851-853; ahs. in Chcin. Ztg., .33 {1909), No. 73, Rcpcrt., 

 p. 311). — This is a study of the amouut of protein acids which are discharged 

 under normal physiological conditions, and of a few cases of the eliminations 

 under pathological conditions. 



The digestion of fat in the animal body, S. J. Levites {Biochem. Ztschr., 

 20 {1909), No. 3-5, pp. 220-223).— Using egg-yoke fat, olive oil, and other fats, 

 experiments were made with dogs from which the author concludes that when 

 fat is fed either alone or mixed with other foodstuffs only a very small quan- 

 tity is saponified in the stomach. 



The absorption of fat stained with Sudan III, L. B. ]\Iendel {Amer. 

 Jour. Physiol.. 2'i {1909), No. 5, pp. .'i93-.'i9G). — From his experimental data the 

 author concludes that " when fat stained with water-insoluble dyes, like Sudan 

 III, is fed, the pigments readily pass into the lymphatic vessels and thereby 

 reach the blood stream. Since these compounds are soluble in free fatty acids 

 as well as in neutral fats, their presence in the lypmh can not be taken as 

 evidence either for or against the possibility of the digestion of fats prior to 

 their absorption." 



The excretion of sulphurous acid by a man in experiments with sodium 

 sulphite and with sulphurous acid combined with sodium salts, F. Franz 

 and G. Sonntag {Arb. K. Gsndhtsaint., 2S {1908), No. 1, pp. 225-260).— The 

 occurrence of volatile sulphur compounds in urine distillates is not to be re- 

 garded as proof of the presence of sulphurous acid since acidulated human 

 urine under normal conditions yields such compounds, the nature of which is 

 in part unknown. Since the normal amount of these compounds can not be 

 definitely determined, it is necessary in estimating sulphurous acid in urine to 

 calculate the amount of such volatile bodies and also to make sure that the 

 sample shows the presence of sulphurous acid. In the case of man as with 

 animals (dogs) the greater part of the sulphurous acid taken into the stomach 

 is recoverable as sulphate. By exercising great care and testing at intervals 

 of 10 or 15 minutes, sulphurous acid may be detected in the urine, but in no 

 case in quantity greater than 1 per cent of the total amount taken. 



The results obtained in the experiments on the excretion of sulphurous acid 

 when taken in the form of salts are in accord as regards physical-chemical 

 relations with those secured from pure aqueous and acid solutions. 



The effect of age and size upon the respiratory exchange of infants, 

 A. Schlossmann and II. Murciiiiauser {Biochem. Ztschr., 18 {1909), No. (J, pp. 

 1/99-505). — From tests with an infant at diffei-ent times it appeared that the 

 carbon dioxid excretion and oxygen consumption per square meter of surface 

 area did not vary with increasing age, and that in reality metabolic changes 

 are proportional to surface area. 



An apparatus for studying the respiratory exchange, F. G. Benedict 

 (Amer. Jour. Physiol., 2.', {1909), No. 3, pp. 3-'i5-37Ji, flys. «).— The princii»le 

 used in the respiration calorimeter experiments for measuring respiratory fac- 



