240 STORRS AGRICULTURAL EXPERIMENT STATION. 
of different classes, with different occupations, and in different 
conditions of life. ‘That such inquiries may be valuable for 
the study of food and nutrition in disease is equally apparent. 
Of course they are fundamentally necessary for more thorough 
understanding of the economy of feeding domestic animals. 
SUMMARY. 
Lhe experiments with the respiration calorimeter here described 
had a two-fold purpose, to test the accuracy of the apparatus and 
methods, and to determine the balance of income and outgo of 
matter and energy in the body. They are preliminary to more 
extended research upon some of the fundamental problems of 
nutrition. | , 
Lhe apparatus consists essentially of a metal-walled chamber in 
which a man lives, eats, drinks, works, and sleeps. Provtston ts 
made for ventilating the chamber and Sor regulating the tempera- 
ture and moisture of the atr within tt. The volume of atr tn the 
ventilating current ts measured; the food, drink, excreta, and 
respiratory products are weighed and analyzed, and their poten- 
tial energy ts determined, as ts the kinetic energy given off from 
the body in the forms of heat and external muscular work. 
The accuracy of the apparatus and methods for the determina- 
tions of carbon dioxide, zyater, and heat was tested by heat gener- 
ated in the chamber by. passing an electric current through a 
resistance cowl, and by burning ethyl alcohol wethin the chamber. 
In the electrical tests the measurements of heat generated and 
found were practically identical. In the alcohol tests the average 
amounts found by actual experiment were: for carbon, 99.6 per 
cent., hydrogen, 100.6 per cent.; and heat 99.8 per cent. of the 
theoretical amounts. It thus appears that this apparatus when 
used for the analysis of alcohol and the determination of tts heat 
of combustion gives results nearly, if not quite, as accurate as 
are obtained by the ordinary laboratory methods. : 
Al series of experiments with men have been undertaken, two 
of the earlier of which are here reported. These are intended for 
the study of several problems. The question especially considered 
here ts this: Is the energy given off from the body in the form of 
heat, or of heat and external muscular work, equal to the poten- 
teal energy or heat of combustion of the material actually burned 
wn the body? In other words, when the compounds of the food and 




