4 10 Influence of Inanition on Metabolism. 



of the experiments with Breithaupt, observations were likewise made during 

 work. From the data obtained during these short experiments, the authors 

 computed the total carbon dioxide output of these fasting men. 



The daily total elimination for the 10 days of Cetti's fast was estimated to 

 be 567, 501, 482, 478, 470, 467, 502, 526, 489, and 449 grams, respectively. 

 A cold on the second day and intestinal irritation on the third and fourth days 

 of Breithaupt's fast so invalidated the results for the short periods that the 

 authors did not attempt to compute the 24-hour output from the data obtained. 

 In a subsequent discussion of results, the authors recognized the fact that the 

 observations were made during a period when bodily activity was at a minimum, 

 and consequently the results obtained by computation were arbitrarily increased 

 by one-fifth, in an attempt to approximate the probable increase of carbon 

 dioxide during periods of ordinary muscular activity. The carbon dioxide 

 production thus measured was the basis of the calculations for water of respira- 

 tion and perspiration. 



Hanriot & Richet, 12 * with a different form of respiration apparatus, deter- 

 mined the carbon dioxide output of a man weighing 50 kilograms who fasted 

 for 46 hours. The amounts liberated per hour were 15.3, 14.15, 14.30, and 

 14.35 liters after the seventeenth, twenty-fourth, twenty-ninth, and forty-sixth 

 hours of the fast. The authors did not compute the output per 24 hours from 

 these short experiments, but concluded from the results obtained that at the end 

 of a few hours of complete fasting, the respiratory exchange becomes constant. 



Luciani (4) attempted during the Florence fast to determine the carbon di- 

 oxide elimination of Succi. The experiments were all of short duration and 

 the method and results have been criticised by Zuntz (7). According to Luci- 

 ani's results the total output of carbon dioxide on the day before the fast was 

 479 grams and on the tenth, twentieth, and twenty-ninth fasting days 435, 

 406, and 387 grams, respectively. 



Experiments in which the carbon dioxide production of fasting men was 

 determined during the major part of the 24 hours were first made by Banke. 12 * 

 Ranke made 3 fasting experiments on himself, in the Pettenkofer respiration 

 apparatus, and as has been pointed out before, these were the first experiments 

 made with this historic apparatus. The length of the periods was 24 hours. 

 One experiment, at least, represented the second day of fasting, since the 

 subject had already fasted 24 hours. In reporting the results, the author 

 states that he found after the experiments were made that the apparatus gave 

 results somewhat too high. Accordingly, he assumed an average carbon dioxide 

 production of 663 grams (180.85 grams of carbon) for the 3 fasting days. 



m Comptes Rendus (1888), 106, p. 496. 

 ^Archiv Anat. u. Physiol. (1862), p. 340. 



