Experiments on the metabolism of matter and energy in the human body / By W.O. Atwater, PH.D., and F.G. Benedict, PH.D., with the cooperation of A.W. Smith, M.S., and A.P. Bryant, M.S.

  • Wilbur Olin Atwater
Date:
1899
Catalogue details

Licence: Public Domain Mark

Credit: Experiments on the metabolism of matter and energy in the human body / By W.O. Atwater, PH.D., and F.G. Benedict, PH.D., with the cooperation of A.W. Smith, M.S., and A.P. Bryant, M.S. Source: Wellcome Collection.

Provider: This material has been provided by the Augustus C. Long Health Sciences Library at Columbia University and Columbia University Libraries/Information Services, through the Medical Heritage Library. The original may be consulted at the the Augustus C. Long Health Sciences Library at Columbia University and Columbia University.

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    These tests appear to prove that, if the combustion of alcohol in this form of lamp is not complete, the products of incomplete combustion are so extremely small that they would affect the results, when alcohol is burned in the calorimeter for the production of a known amount of carbon dioxid, water, and heat, by less than 0.01 per cent, a value far within the limits of experimental error. THE RESULTS OF ALCOHOL TEST EXPERIMENTS. In the detailed description of these experiments in the previous bul- letin it was explained that ethyl alcohol of about 90 per cent was used. The theoretical quantities of carbon dioxid and water which would be produced by its combustion were computed from the known composi- tion of ethyl alcohol and water and the amounts of these materials in the alcohol actually used. The heat of combustion was determined by burning specimens of the alcohol with oxygen in the bomb calorimeter above referred to. Different determinations of the heat of combustion made by this apparatus agreed with tolerable closeness. The aver- age of the results was not far from that obtained by Berthelot. We can hardly believe that the heats of combustion as thus determined were very far out of the way.' In the test experiments the alcohol was burned inside the respiration chamber by use of the lamp above described. The general method of conducting the experiments was the same as followed in the metabolism experiments with a man inside the chamber. These tests were made from time to time during the progress of the metabolism experiments described beyond. Table 2 summarizes the final results of nine experiments thus made. Table 2.—Summary of nine alcohol test experiments tvifh respiration calorimeter. Date. 1897. April 27-29 May 10-11 May 26-27 October 27-28 November 2-3 December 2 1898. January 6 January 24-27 May 9 Totala Duration. Hrs. min. 52 31 29 33 34 35 11 Alcohol burned. Orams. 955.4 798.8 505.4 797.7 788.2 245.3 112.2 1,607.8 699.7 Carbon dioxid. Required. Orams. 1,657.2 1,385.6 876.7 1, 384.8 1,365.1 423.1 193.5 2,784.4 1,206. 9 9,892. 5 Found. Orams. 1, 657. 6 1, 384.4 887.8 1,335.7 1, 376.7 417.6 193.5 2,769. 7 1,198.9 Ratio of amount found to amount required. 9,886.2 Per cent. 100.0 99.9 101.3 [96.6] 100.8 98.6 100.0 99.5 99.4 99. a Omitting the carbon diosid and water in test No. 4 and the water in test No. 3. ' For detailed results see U. S. Dept. Agr., Office of Experiment Stations Bui. 63.