METABOLISM OF MATTER AND ENERGY IN THE 
HUMAN BODY. 
INTRODUCTION. 
The present report gives the details of 13 experiments upon the 
metabolism of matter and energy in the human body, made at Middle- 
town. Conn., under the auspices of the U. S. Department of Agricul- 
ture, in cooperation with the Storrs Experiment Station and Wesleyan 
University. These experiments, which are in continuation of those 
reported in earlier bulletins of this series. a were carried on during the 
years L s, .»s to 1900, with the same respiration calorimeter b and by the 
same methods. In addition to the experiments reported in the present 
bulletin. 11 other experiments, which for convenience of reference 
have been numbered consecutively with these, were made with the 
same apparatus at Wesleyan University, during the same years, in 
connection with an independent investigation, and are reported 
elsewhere. 
QUESTIONS STUDIED. 
As has already been explained, the ultimate purpose of experiments 
with men in the respiration calorimeter is the study of some of the 
fundamental laws of nutrition, and the whole inquiry is based upon 
the principle that the chemical and physical changes which take place 
within the body, and to which the general term "metabolism" is ap- 
plied, occur in obedience to the laws of the conservation of matter and 
of energy. 
No one doubts that the law of the conservation of matter governs 
its metabolism in the living organism, and it is generally believed that 
the law of the conservation of energy likewise applies to the metab- 
olism of energy. Quantitative determinations of the applications of 
this law are. however, desirable. 
*U. S. Dept. Agr., Office of Experiment Stations Buls. 44, 63, and 69. 
b U. S. Dept. Agr., Office of Experiment Stations Buls. 44 and 63. See also Conn. 
(Storrs) Sta. Rpt. 1897, p. 212, and Physical Review, 9 (1899), pp. 130-163, 214-251. 
c Memoirs of the National Academy of Sciences, Vol. VIII, Sixth Memoir, 1902. 
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