The early history of chlorine : papers / by Carl Wilhelm Scheele (1774), C.L. Berthollet (1785), Guyton de Morveau (1787), J.L. Gay-Lussac and L. J. Thenard (1809).

Date:
1905
Catalogue details

Licence: In copyright

Credit: The early history of chlorine : papers / by Carl Wilhelm Scheele (1774), C.L. Berthollet (1785), Guyton de Morveau (1787), J.L. Gay-Lussac and L. J. Thenard (1809). Source: Wellcome Collection.

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    at least as regards combined water. But it is not the same with muriatic acid gas; it does not contain hygro- metric water, it is true, but it contains it intimately combined, as MM. Henry and Berthollet first showed. We have even succeeded, by passing muriatic acid gas at a moderate heat over litharge which had been fused and then reduced to coarse powder, in extracting and collecting this water, which must form about one fourth part of its weight, according to various experiments we have made and which will be reported in the subsequent part of this Memoir. The other gases do not comport themselves with water like the preceding ones. None of them contains com bined water, and all contain hygrometric water. It follows from this that fluoric acid gas,* and probably also ammonia gas, does not contain either hygrometric or combined water, that muriatic acid gas does not contain hygrometric water and contains it combined ; and that all the others contain only hygrometric water. The most striking thing in these results is to find that muriatic acid gas contains water, and that fluoric* and ammoniacal gases do not contain it; and especially to find that muriatic acid gas contains it in such proportions that if it were entirely decomposed by a metal all the acid would be absorbed by the oxide and transformed into metallic muriate. This is exactly what takes place, as we have assured ourselves, when muriatic acid gas is passed slowly and successively through several gun-barrels filled with iron turnings and raised to a red heat. The more we reflect on all these phenomena the more we see that it is difficult to account for them. Might it not be possible however that oxygen and hydrogen are two of the constituent principles of muriatic acid gas, that * [Sec note p. 35. ]