258 MEMOIRS OF THE NATIONAL ACADEMY OF SCIENCES. 



times, even this conclusion .should be held with a degree of reserve. While it is statistically 

 valid for these experiments, the extent to which it would be true in general experience is by no 

 means certain. 



PROPORTIONS OF ALCOHOL OXIDIZED AND UNOXIDIZED. 



The difference between the amount of alcohol taken into the body in food and the amount 

 given off unoxidized by the kidneys, lungs, and skin is taken as the amount oxidized in the body. 

 For the determination of the amounts not oxidized in the body quantitative examination was 

 made of the several excretory products for the presence of alcohol. No similar examination of 

 the feces for alcohol was practicable; but, as it has been found in other experiments 1 that no 

 alcohol was excreted through this channel, even when considerable quantities were ingested, it 

 was here assumed that the feces would contain no appreciable amount of the alcohol taken with 

 the food. 



The alcohol eliminated by the kidneys would, of course, be found in the urine; that given 

 off by the lungs and skin in the "drip" water collected from the surface of the system of cool- 

 ing tubes, or it might pass out of the chamber as vapor in the air current and be condensed in 

 the "freezers." in which a large part of the water is collected from the outgoing air, or it might 

 even pass through the freezers as vapor and be ultimately absorbed in concentrated sulphuric acid 

 in an apparatus arranged for the purpose. 



The determinations of the amounts of alcohol given off from the body unoxidized in experi- 

 ment No. 7 were made according to the method described by BoDLANDEE. b This method, how- 

 ever, does not give results sufficiently accurate when the amounts of alcohol are as small as were 

 found in these experiments. In the latter experiments a modification of this method was used, 

 which has been shown to give very satisfactory results in the determination of extremely small 

 quantities of alcohol. 



The urine, drip water, and freezer water were distilled several times in order to separate 

 the alcohol and other volatile and readily oxidizable organic matters and to obtain them in a 

 more concentrated form. The amount of organic matter (here designated as reducing material) 

 in the distillates was then determined by the method mentioned above. The amount of reducing 

 material in the air current was estimated by passing the outgoing air through bulbs containing 

 concentrated sulphuric acid, and determining the amount of reducing material in the acid. The 

 total amount of reducing material thus determined in the various excretory products was 

 calculated as alcohol. 



Other investigators' 1 have found evidence that such reducing materials are excreted by the 

 body when no alcohol was ingested. In several experiments in which alcohol did not form part 

 of the diet, examinations of respiratory and excretory products were made the same as when 

 alcohol was given, and reducing materials were found to be present." The average amount found 

 in these experiments without alcohol was, therefore, deducted from the total amount determined 

 in the experiments with alcohol and the difference taken as alcohol excreted, as shown below: 



Alcohol ingested and exereted unoxidized. 



Alcohol ingested, average 13 experiments grams.. 72.3 



Reducing material in excretory products: 



When alcohol way ingested, average 13 experiments grams. . 1.6 



When no alcohol was ingested, average 6 experiments do 3 



Alcohol excreted grams.. 1. 3 



Total alcohol metabolized do 71 



Do per cent.. 98. 2 



"Sec Bodlander in Arch. Physiol., Pfluger, 32 (1883), p. 424. 

 b Loc. cit. 

 See Benedict and Xorris on "The Determination of Small Quantities of Alcohol," Jour. Am. Chem. Soc, 20 

 (1898), p. 299. 



'Inipiv. Proc. Roy. Soc. (London), 20 (1871-72), 268. See also Billings, Mitchell, and Bergev on "The 

 composition of expired air and its effect upon animal life." Smithsonian Contributions to Knowledge, XXIX 

 (1895). No. 989. 



See Table ('XXI in the Appendix. 



