664 



EXPERIMENT STATION RECORD. 



cienta of digestibility and the energy available in the different experi- 

 ments. 



L'exiili of digestion experiments with man. 



Num- 

 ber "i 

 experi- 

 ment. 



Meta- 

 bolism 

 experi- 

 ment 

 Dum- 

 ber. 



I tescription. 



PIH8T PERIOD. 



Mixed diet, mil in ry work 



Mixed diet, hard work 



Mixed diet, with alcohol, rest 



Mixed diet, light work 



...do 



.Mixed diet, witli alcohol, rest 



Mixed diet, hard work 



Mixed diet, with alcohol, hard work 



Average of 8 periods 



SECOND PERIOD. 



Mixed diet, rest, 



Mixed diet, hard work 



Mixed diet, with alcohol, rest 



Mixed diet, rest 



...do 



Mixed diet, with alcohol, rest 



Mixed diet, hard work 



Mixed diet, with alcohol, hard work 



Average of 8 periods 



Protein. 



cent. 

 92. 7 



90.1 

 90.9 

 91.4 

 90.9 

 94.9 

 90.6 

 0'-. :; 



92.1 



91.4 

 92.2 

 94.7 

 94.0 

 93.4 

 92. 9 

 88.8 

 93.6 



92. G 



Fat. 



Per cent. 

 94. 

 95.3 

 93.6 

 94.5 

 92.1 

 91'. 1 

 93.2 

 94. 3 



Carbo- Available 

 hydrates, energy. 



93.6 



93.9 

 96.9 

 96.3 

 95.6 

 93.9 

 88.1 

 93.0 

 95.9 



94.2 



Per rent. 

 98.0 

 '.i7. 6 

 98.3 

 97.4 

 95.8 

 98.6 

 97.8 

 96.4 



97.5 



97.6 

 98.3 

 98.8 

 98.2 

 96.5 

 97.8 

 97.5 

 98.7 



97.9 



■ cent. 



89. 9 

 91.2 

 89.8 

 89.7 

 88.4 

 91.3 

 91 2 

 91.2 



90.3 



90.(1 

 92. 6 

 91.8 

 90.7 

 89.5 

 90.2 

 90.9 

 93.1 



91.1 



A respiration calorimeter and experiments on the conservation 

 of energy in the human body, W. O. Atwater and E. E. Eosa 

 {Connecticut Storrs Sta. Rpt. 1897, pp. 212-242, figs. 3).— The portion of 

 this apparatus which is concerned in the determination of income and 

 outgo of material has already been described (E. S. E., 9, p. 803). In 

 the present publication the portion which has to do with the measure- 

 ment of income and outgo of energy is described, as well as check 

 experiments in which heat Mas liberated in the respiration chamber by 

 burning alcohol and by meaus of an electric current and 2 experiments 

 with man. The metal M r alls of the respiration chamber are kept at 

 the same temperature, therefore no heat can pass in or out of the 

 chamber through the walls. The ventilating current is kept at the 

 same temperature as it enters and leaves the chamber. Heat gener- 

 ated in the chamber is absorbed by a current of water, which passes 

 through "absorbers" within the chamber. The various devices for 

 measuring the current of air, controlling its temperature, for sampling 

 the air, measuring the heat of the incoming and outgoing currents of 

 water, and other devices are described in detail. 



"In order that the ventilating current of air shall not carry out of the chamber 

 anymore or any less heat than it brings in, the temperature must he the same when 

 it enters as when it leaves. Accordingly the incoming air, which leaves the brine 

 tank [where it is largely freed from moisture by ooolingl at a very low temperature, 

 is warmed before its entrance to the chamber to the temperature of the outgoing 



