276 MEMOIRS OF THE NATIONAL ACADEMY OF SCIENCES. 



cold, the production of heat in the body might have been retarded, and the radiation increased 

 so as to lower the body temperature by several degrees. 



RAPIDITY OF COMBUSTION OF ALCOHOL IN THE BODY. 



There is a popular impression that alcohol is burned in the body much more rapidly than 

 ordinary food, and that in consequence not only is the energy resulting from its oxidation wasted, 

 but derangements of bodily functions may result from the rapid combustion of the alcohol. The 

 exact grounds for the belief or nature of the supposed disturbances we have not seen distinctly 

 stated. Nevertheless, as the impression prevails to some extent, at least among physicians and 

 physiologists, it seems to demand consideration. 



Leaving out of account the unsettled question as to how soon after the ingestion of the alcohol 

 its oxidation begins, the main problem is the rate of oxidation. If it is especially rapid, either 

 one of two results may follow. The oxidation of other materials may go on as usual, in which 

 case the total production of carbon dioxid and heat will be abnormally large: or the oxidation 

 of other substances may be diminished so as to compensate for more or less of the oxidation of 

 the alcohol, in which case the rate of production of carbon dioxid and heat may be little, if any. 

 larger than without the alcohol. The natural test will be found in the measurement of these 

 rates of production. So far as we are aware no adequate tests of this character have thus far 

 been made. 



In examining the literature of the subject we have not succeeded in finding any experimental 

 proof that the rate of elimination of carbon dioxid or heat from the body is materially increased 

 or decreased by moderate quantities of alcohol. Satisfactory tests would involve the measurement 

 by short periods, as, for instance, hour by hour. Our own experiments were not planned for 

 this purpose, and the measurements were made generally in six-hour periods. There was noth- 

 ing in the observations to imply that the rate of production of either carbon dioxid or heat was 

 materially increased either immediately after the ingestion of the alcohol or later. 



Part of the heat given off from the body is carried away in water vapor given off' from the 

 lungs and skin, hut the larger portion finds its way to the water current, by which it is carried 

 out of the chamber. The rate of flow of this current and its rise of temperature in passing 

 through the chamber thus measure the rate of evolution of heat from the body other than that 

 carried away b} T water vapor. 



The observations of rate of flow and rise in temperature are made every few minutes, and 

 thus show the rate of evolution of the larger portion of the heat. 



We have taken the pains to calculate the evolution of heat for hourly periods for three series 

 of experiments, in which the alcohol diet and ordinary diet were compared, viz. Nos. 22-24, 

 26-28, 29-31. The calculations, however, have been limited to the night periods between 7 p. m. 

 and 7 a. m., because the evolution of both carbon dioxid and heat is much more regular by night 

 than by day, and any disturbance, such as might be caused by the rapid oxidation of alcohol, 

 would be more easily detected in comparing the figures for the experiments with and without 

 alcohol during the night periods. 



The results of these comparisons are negative. There are practically no more irregularities 

 or indications of disturbance in the alcohol than in the nonalcohol experiments. There is nothing 

 in the figures which seems to us to indicate any appreciable tendency toward increase of heat 

 production during the first, second, or third hour after the ingestion of the alcohol. The figures 

 are. indeed, so destitute of such indications as to hardly warrant their printing. 



We are therefore led to the conclusion that in these experiments either the alcohol was not 

 suddenly or rapidly oxidized, or if there was such rapid oxidation, there was a corresponding 

 decrease in the oxidation of carbohydrates, fats, or protein. 



It is interesting to note that this conclusion accords with the other observations, viz, those of 

 the total heat production and the economy of the use of energy in the rations with or without 

 alcohol. All of these imply that the alcohol, carbohydrates, and fats simply replaced one another 

 as sources of energy: that as either was oxidized the others were proportionately spared. 



