Page:Proceedings of the Royal Society of London Vol 1.djvu/407

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The product from mercury was corrosive sublimate.

The compound formed with iron was of a bright brown, iridescent, like the Elba iron ore. volatile at a very moderate heat, and forming brilliant crystals on the sides of the vessel.

Tin afforded Libavius’s liquor, having its usual properties.

When instead of the metals themselves their oxides were exposed to the action of oxymuriatic gas, oxygen was given ofl’, in most cases at a heat below redness; and the quantity was the same as had been previously absorbed by the metals.

Rom the whole of the present series of experiments, Mr. Davy derives confirmation of his former opinion respecting the simple nature of oxymuriatic gas, the leading property of which is its tendency to unite with inflammable bases, forming binary compounds. Since its affinity is in most cases greater than that of oxygen, it either produces the expulsion of the oxygen, or causes it to enter into new combinations. He considers the oxygen that is expelled to arise from the oxide. because it is in proportion to the quantity which the oxide contained, and bears no relation to the quantity of acid.

If the oxymuriatic gas consisted of any acid matter combined with oxygen, its acidity, says Mr. Davy, should appear when it is united to phosphorus. But when two parts of this gas are combined with one of phosphorus, the compound has no efi'ect on litmus paper. and does not act on dry lime or dry magnesia. But by union with hy- drogen it forms an acid; in the same manner oxygen communicates acid properties to sulphur and phosphorus.

Although its affinities are in general superior to those of oxygen, Mr. Davy notices some exceptions. For instance, the boracic and phosphoric acids are not decomposed by it; and the same appears to be the case with the peroxides of iron and arsenic.

Of all the different bodies supposed to be elementary, nitrogen is that which has the weakest tendencies to combination in general; and it does not hitherto appear to have any aflinity for oxymuriatic gas.

With respect to the simple or compound nature of nitrogen, Mr. Davy has not yet arrived at any sat‘nsfactory conclusion, although the general result of his attempts to decompose it has shown an apparent evolution of hydrogen, and other effects which could only be ascribed to the presence of oxygen.

But, on the contrary, the numerical expression for nitrogen, which corresponds to 134, does not accord with any simple proportion of oxygen and hydrogen; and this, together with other circumstances, occasion Mr. Davy to resist the inference of its being decompounded.

The author concludes with reflections on the nomenclature of oxy- muriatic gas, and its compounds; since it appears to him that an alteration is necessary to assist the progress of discussion, and to diffuse just ideas on the subject.

It is to be regretted that the great discoverer of this substance did not originally affix to it a simple name to which we might now recur; but his term dephlogisticated can hardly be adopted in the present state of science.