376 EXPERIMENT STATION RECORD. 



total work done each day ranged from nearly 20,000,000 to nearly 7,000,000 foot- 

 pounds, and the corresponding heat equivalent from 6,381 to 2,256 calories, averaging 

 3,994 calories. 



"The amount of work done by Albert was slightly less than that by Miller, rang- 

 ing from 12,000,000 to 4,000,000 foot-pounds per day, with a corresponding range in 

 heat equivalent from 3,938 to 1,334 calories. The average heat equivalent of the 

 work done per day during the 6 days is 2,760 calories, and the average energy in the 

 food as found by actual determination of the heat of combustion is 6,307 calories, 

 making an apparent efficiency of nearly 45 per cent. . . . 



" If the equivalent exposure of the rider is assumed as equal to 4 sq. ft., the total 

 amount of work done each day varied from nearly 16,000,000 to a little over 5,000,000 

 foot-pounds, with a corresponding range in heat equivalent from 5,088 to 1,686 

 calories, with an average for the 6 days of 3,547 calories." 



It is pointed out that in each case there is some uncertainty regarding the energy 

 of the food consumed, since a greater or less amount of body fat was also consumed, 

 the energy of which should be taken into account in estimating the total income. 

 This would diminish somewhat the apparent efficiency. 



"Under the conditions of the race the amount of energy exerted can be considered 

 about the limit of human strength and endurance. This is reasonably many times 

 greater than would be exerted by the ordinary laborer working under the routine of 

 his usual occupation. ' ' 



On tlie influence of food consumed upon metabolism, G. Koraen {Skand. 

 Arch. Physiol., 11 {1900), No. 3-4, pp. 176-197). — The respiratory quotient and the 

 hourly excretion of nitrogen were studied under different dietary conditions, the 

 author being the subject. A number of his conclusions follow: When some 66 gm. 

 of fat is consumed the total metabolism is not increased. When some 165 gm. of cane 

 sugar is consumed it is increased somewhat, and markedly increased when 52 gm. of 

 protein is consumed. A marked increase is also observed when a mixed diet which 

 is rather difficult of digestion is consumed. When fasting, the hourly excretion of 

 nitrogen is 0.414 gm.; that of carbon, 6.05 gm., with a possible error of zfc 0.19 gm. 

 These values are equivalent to 72.1 calories, with a possible error of ±2.3 calories. 



Respiration experiments ■with a corpulent subject when work w^as per- 

 formed and the moisture content of the air varied, A. Broden and H. Wolpert 

 {Arch. Hyg., 39 {1901), No. 3, pp. £98-311). — In these experiments the respiratory 

 quotient w^as determined. The large amount of water in the respiratory products 

 explains the great thirst experienced by corpulent persons. The experiments are 

 discussed in considerable detail, especially with reference to the performance of work 

 by corixdent and thin jiersons in the tropics. 



Contribution to the subject of gastric juice and the composition of its 

 enzyms, M. Nexcki and N. Sieber {Ztschr. Pln/.iicjl. Chem.,3£ {1901), No. 3-4, pp. 

 291-319). — Experiments are reported and discussed. 



Concerning the theory of digestion of protein, W. W. Sawjalow {Arch. 

 Physiol. IPfluger], 85 {1901), No. 4-6, pp. 171-325).— X. chemical study of the digesti- 

 bility of proteids with an extended discussion. 



Contribution to the physiology of digestion. Ill, A substance increasing 

 the flow of digestive juice, C. Radzikowski {Ardi. Physiol. [Pfliiger], 84 (1901), 

 No. 11-12, ]>p. 513-526). — Studies on the effect of alcohol on peptic digestion. 



Contribution to the physiology of digestion. IV, Two pepsin-forming 

 bodies, F. R. Mark-Schnorf {Arch. Physiol. [Pfugerl, 85 {1901), No. 1-3, pp. 143- 

 148). — Experiments with a dog are reported which led to the conclusion that white, 

 so-called pure dextrin neither causes a secretion of digestive juice nor formation of 

 pepsin. Inulin and glycogen, even when chemically pure, cause the formation of 

 pepsin without causing a secretion of digestive juice. 



