MEMOIES OK THE NATIONAL A.CADEMY OF SCIENCES. 



259 



From Table CXXI1 in the Appendix it will be observed that the quantities of alcohol 

 eliminated by the lungs, skin, and kidneys varied from o.T to 2.7 grams, and averaged 1.3 grams 

 per day. These quantities correspond to a range of from 1 per cent t<> 8.7 per rent and an 

 average of 1.9 per cent of the total amount of alcohol ingested. We consider, therefore, that in 

 general when alcohol is taken in small doses not more than 2 per cent is given off unoxidized. 

 and the resultsof the later experiments indicate that this figure is really too large. Accordingly, 

 the coefficient of availability of alcohol is taken as 98 per cent. 



Comparing this with the coefficients of availability of protein, fat, and carbohydrates in the 

 diet with alcohol, as given in the Table 12, p. 257. it appears that the coefficient of availability 

 of alcohol in these experiments was practically the same as that of the carbohydrates and 

 larger than those of fats and protein of ordinary food. That is to say, it was found that 2 per 

 cent or less of the total alcohol ingested in these experiments was given off unoxidized by the 

 lungs and skin, while on the average about 2 per cent of the carbohydrates, 5 per cent of the 

 fats, and 7 per cent of the protein of the ordinary diet appeared to be excreted unoxidized. 



The conclusion is that in these experiments the alcohol was more completely consumed than 

 arc the nutrients of ordinary mixed diet. 



METABOLISM OF THE ENERGY OF ALCOHOL. 



it was stated above that the experiments with men in the respiration calorimeter had shown a 

 very close agreement between the income and outgo of energy in the body, and that this was 

 regarded as practically a demonstration that the law of the conservation of energy holds in the 

 living organism. Up to April. 1900, the results of 30 such experiments had been obtained. 

 These covered, all told, 93 days; they were made with 4 different subjects, under various con- 

 ditions of diet and occupation. When the figures for individual days or for individual experi- 

 ments are considered, there appears to be more or less disagreement between the figures for 

 income and those of outgo energy, though the differences are inside the natural range of error in 

 such physiological experiments. When the results of all the experiments are averaged together, 

 however, the differences counterbalance each other, and the daily income, 2,718 calories, is found 

 to be practically identical with the daily outgo, 2,716 calories. This agreement is in accordance 

 with the law of the conservation of energy, and thus confirms the belief that this law governs 

 the metabolism of energy in the living organism. 



In 13 of the 30 experiments referred to alcohol formed a part of the diet. The results of these 

 experiments compared with those without alcohol imply very clearly that the law of the conser- 

 vation of energy holds as well with the diet containing alcohol as with the ordinary diet. This 

 may be seen from Table 13. which epitomizes the more detailed statistics given in Table CXX in 

 the Appendix, and compares the averages of the results of the rest and the work experiments in 

 which alcohol formed part of the diet with those of similar experiments without alcohol. Both 

 those experiments that are strictly comparable and those less comparable, as explained on a pre- 

 ceding page, are here included. 



Table 13. — Metabolism of '< m rgy. Averages of results of experiments with ordinary and with alcohol diet. 



Experiments with and without alcohol. 



Energy of 

 net income. " 



MORE DIRECTLY COMPARABLE. 

 Rent expi run, uts. 



Without alcohol: Nos. 9, 24. 26, and 28. 

 With alcohol: Nos. 10, 22, 27 



Work experinu nts. 



Energy of outgo measured as- 



CalOries. 



2,190 

 2,191 



3,660 

 3,690 



Without alcohol: Nos. 11, 29 and 31, 32 and 34 



With alcohol: Nos. 12, 30, 33 



"Estimated energy of material actually oxidized in the body 



