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to object against those experiences, Muller says, that the lungs of the frogs still contained a certain amount of atmospheric air, and that perhaps there was carbonic acid in its intestinal channel. Here is why I repeated them, beginning by taking the animals to the vacuum, that I filled after of purified hydrogen gas. In this new experience, the hydrogen was equally changed a lot of times, in order to remove until the last remains of atmospheric air. One also checked that, after the absorption of the aqueous vapor by the calcic chloruride, the caustic potash didn't determine more any gas decrease. The frogs were three hours in the hydrogen; there is a long time they were suffocated. They were removed from there and undressed the gas of all the humidity, introducing, a lot of times in the duration a whole day, a small tube of calcic cloruride, until that the salt ceased of humidifying. Only then that one went in demand of the carbonic acid through the caustic potash. In the two experiences done like this, it was discovered the ordinary exhalation of carbonic acid; the 1st gave 0,3 of cubic inch, and the 2nd 0,37. Lately Bischoff came equally with his equaly instructive experiences to confirm these notions; frogs which he had tied and it had extracted the lungs, they continued to exhale carbonic acid by the skin. These experiences, demonstrating the exhalation of the carbonic acid in the lungs and in the skin, they don't care being he secreted by those organs, since some of them completely prove its preexistence in the fluid to be arterialized, as well as of Magnus' excellent inquiries its preexistence is already concluded in the same arterialized fluid, where in fact they are broken the first proportions, ceding the gas in question of predominance to its powerful rival, the oxygen, tireless agent of the revolutions of the organism, whose pereniality is the life.

Of whatever it is said one concludes irremissibly the existence in the blood of the carbonic acid exhaled by the lungs and skin, and that in those points he is just freed. Here a difficulty is opposed: in what the blood contains it? in simple dissolution or in more intimate combination? Liebig considers doubtful that this gas is in the blood in the free state, and it believes even that its state is problematic, being founded in the affinity of the fibrin by the oxygen, after whose combination appears carbonic acid, as they prove the experiences of Scherer: and following his calculations and experiences, he wants it comes in combination with the soda, forming a super-salt, that is, sodic bicarbonate. However Magnus, also calculating, it shows that the amount of the obtained carbonic acid of the blood by the gas hydrogen, is very considerable to be attributed to the sodic salt, that the blood contains and it establishes its simple dissolution, as well that the blood may dissolve other gases. In this collision of opinions of such respectable contenders, the most reasonable is to look for its conciliation, distributing the reason with both, although difficult it is to discover the chemical force, by which the presence of a gas determines the metamorphosis of the sodic bicarbonate in neutral salt, because that would never be possible to maintain a dissolution of sodic bicarbonate in this case