Theories and Experiments 277 



changes produced in different physiological or pathological states by 

 variations in the weight of the atmosphere; others in which I produced 

 these variations artificially. Those whose results I am submitting to 

 the Academy today refer to the different periods of generation in 

 mammals from conception to the time of delivery. 



In the book which he published at the time of his return to 

 France, Coindet lir ' returns to the question of the quantity of car- 

 bonic acid formed by men who live on the lofty plateaux. Evi- 

 dently he felt ill at ease on this ground, for in a work of two vol- 

 umes, containing more than 650 pages, he devotes only 5 to this 

 important subject. And yet what could be more convincing in 

 favor of his point than to dwell upon this demonstration that the 

 intra-organic combustions are as active at high altitudes as at sea 

 level? Anoxemia, against which he was battling, would be com- 

 pletely disproved. I confess that at first I expected to find new 

 experiments in this book; there are none, and the explanation of 

 the data is infinitely less complete and detailed in it than in the 

 letters addressed to Michel Levy. 



This is soon explained, for first we record a valuable confes- 

 sion; "I was mistaken", says Coindet (Vol. II, p. 90), "when I 

 formerly wrote weight instead of volume." There is a point 

 gained, and, as I had shown when I recalled the passage copied 

 by Beclard, the notorious 4.51% in 1864 represented to Coindet a 

 proportion in volume, although he said the opposite in his 1865 

 letter. But then, if there is 4.51% of carbonic acid in volume in 

 the air, since the subjects were breathing at the rate of 6 liters 

 per minute, or 360 liters per hour, that makes in one hour 360 

 liters x 4.51 — 16.23 liters of carbonic acid expired. 



Since we are working at 14° and at 58 centimeters, this volume 

 corresponds., at 0° and 76 cm., to 11.77 liters; and as a liter weighs 

 1.966 grams, the production of carbonic acid per hour would be 

 23.14 grams, giving 6.40 grams of carbon consumed. Once more 

 we are far from the 12.30 grams announced triumphantly by 

 Coindet. 



But he thinks better of it: 



We must not lose sight of the fact (he says) that 4.52% in 

 volume, the average amount of carbonic acid exhaled in one minute, 

 has been removed from an air at a temperature of 14°, and a pres- 

 sure of 58 cm., brought to a temperature of 0°, and a pressume of 76 cm. 

 ... so that 6.125 liters, average amount of air expired in one minute, 

 disregarding the Frenchmen who had lately arrived and were not 

 acclimated, give us 367.55 liters in one hour . . . 



When the average of 4.52% of carbonic acid exhaled in one min- 

 ute is accepted, we can establish the following proportion: 



