
98 STORRS AGRICULTURAL EXPERIMENT STATION. 
conditions of work and rest, together with the rates of elimina- 
tion at different periods of the day and night. In this connec- 
tion the respiratory quotient has also been considered. 
10. The temperature of the body and its variation during 
different periods of the day and under different conditions of 
work, rest and sleep. 
11. The need of ventilation in so far as the comfort of the 
person under experiment is affected by the proportions of car- 
bon dioxid and water in the air in the respiration chamber. 
12. Finally a large amount of time, thought and labor has 
been devoted to the elaboration and testing of the apparatus 
and methods of experimenting. Five years were thus used 
before the first actual experiments with men were made. 
APPARATUS AND METHODS. 
The description of the apparatus and of the methods of ex- 
perimenting with it have been given in considerable detail in 
former Reports of this Station* and in publications of the 
Office of Experiment Stations of the U. S. Department of 
Agriculture.; It will be sufficient to mention here that the 
essential features of the apparatus are a chamber seven feet 
long, four feet wide and six and one-half feet high, furnished 
with a folding chair, table and bed, and other appliances for 
physical comfort; apparatus for maintaining, measuring and 
analyzing a ventilating current of air; arrangements for pass- 
ing food and drink into the chamber and for removing the 
solid and liquid excreta, all of which were carefully weighed 
and sampled for analysis; and devices for determining the heat 
given off from the body of the man in the chamber, and, in 
work experiments, a stationary bicycle or other apparatus 
adapted for the performance of muscular work and for deter- 
mining the heat equivalent of the muscular work done. 
The experimental data include measurements of the income 
and outgo of both matter and energy in the man’s body dur- 
ing an experimental period. ‘The chemical analyses include 
determinations of the total quantities of the nitrogen, carbon, 
hydrogen, water and mineral matters of food, drink, and respir- 
atory and excretory products. In obtaining the income and 

* Reports for 1896 and 1897. 
7 U.S. Dept. Agr., Office of Experiment Stations, Buls. 44, 63 and 69. 
