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two fluids, it never comes to interrupt their conflict. It seems that this way there are pointed with enough clarity, and avoided the prolixity, the principal results of the conflict, operated in the lung tissue.

Consumption of the oxygen.

Before entering in the appreciation of the nature of the breathing phenomena, and being already demonstrated the exhalation of the carbonic acid and the absorption of the oxygen, it is convenient to enquire the amount of each one of these gases. Of course only experiences can solve this question, and even them cannot offer in its results the whole desirable certainty, for that that the individual dispositions, the momentary state of the life and the differences caused by the way of trying, they harm your safety; and like this only as an approach owe its data to be accepted. Now, the consumption of oxygen (the weight of the cubic inch being evaluated in 0,42075 grains) it is, according to the first indications of Lavoisier and Seguin, of 41427 p. c. - 17430 grains; according to those two authors' subsequent evaluations, of 38413 p. c. - 16162 grains; according to Davy, of 45504 p. c. 19145 gr.; according to Allen and Pepys, of 39600 p. c. - 16661 grains in twenty-four hours. Uniting the experiences of Lavoisier and Seguin, Davy, Allen and Pepys to the one of Henderson, Nysten and Dalton, and comparing them, one sees that the one of Henderson is the one that gives a weaker result and the one of Davy the highest, being the one of the first of 13 cubic inches per minute and the one of the last 31,6, that are for the man marking the largest and the smallest consumption of the oxygen.

With relationship to the exhalation of the carbonic acid one reads in Muller: - Davy breathed for little more or less than one minute (19 breathings) 161 cubic inches of air, containing 117 of gas nitrogen, 42,4 of gas oxygen and 1,6 of carbonic acid gas. At the end of the experience, the air contained 111,6 cubic inches of nitrogen, 23,0 of oxygen and 17,4 of carbonic acid. He had so exhaled 15,8 cubic inches of carbonic acid in one minute. This amount differs of the average given by Allen's observations and Pepys, that it arises to 22,7 French cubic inches in the same time. The calculation, done according to Lavoisier and Seguin, gives in 24 hours 14930 p. c. or 8534 French grains; according to Davy, 31680 p. c. or 17811 English grains; according to Allen and Pepys 39600 p. c. or 18612 English grains; that equivales in carbon used in the formation of the acid, and consequently eliminated of the blood, to 2820 French grains, according to Lavoisier and Seguin, - 4833 English grains, according to Davy, - 5148 English grains, according to Allen and Pepys. They are taken of Muller all these ciphers, and he adds: -But, and like Berzelius makes to notice, these results are evidently very high, because, as the solid victuals they contain 3/4