Page:Proceedings of the Royal Society of London Vol 1.djvu/406

Rh to potash formed by the combustion of potassiumI then water was instantly formed, and oxymuriate of potassium.

The phenomena when sodium or soda are employed, are precisely analogous to the former; but the quantity of oxygen absorbed by sodium, and extricated from it by oxymuriatic gas, is very nearly twice as much as with potassium.

When two parts of potassium are heated with common salt that has been previously dried, the salt is decompounded; and one part of sodium is obtained in a very pure state by an extremely easy pro- cess.

Burn the experiments on sodium contained in the last Bakeliau lecture, Mr. Davy deduces the elementary number 22, as representing the proportion in which it unites with different bodies.

He observes also, that the proportions ascertained on the present occasion to exist in the hydrates of potash and of soda, accord with the supposition that they each contain one part of water, combined with one of the respective alkali.

The proportions also of potash or soda in different neutral com- binations by these estimates (says Mr. Davy), will be found to agree very nearly With those derived from the most accurate analyses; and as one instance, he refers to Dr. Marcet’s analysis of muriate of soda.

Since the muriates of barytes. lime, and strontia, when thoroughly dried by exposure to a white heat, are not decomposable by boracic acid, or by any simple attractions, Mr. Davy was led to suppose that they consisted of their peculiar metallic bases, combined with oxymuriatic gas; and he is conﬁrmed in this opinion by the result of other experiments; for when these earths are heated to redness in oxymuriatic gas, the same dry muriates are formed, and oxygen is expelled. The proportion which this oxygen bears to each earth, Mr. Davy has not yet ascertained; but he found it to be in the con— stant ratio of one to two in volume of the oxymuriatic gas employcd.

When dry quick-lime was heated in muriatic gas, water was im- mediately formed; and it can hardly be doubted, says Mr. Davy, that this arose from the union of hydrogen from the acid with oxygen from the lime.

The author next endeavoured to obtain the metals of barytes, strontia, and lime, from their muriates by means of potassium; and though he did not succeed in separating them. he is of opinion that either the bases of the earths were wholly or partially deprived of oxymuriatic gas by this process, or that the potassium had entered into triple union with their muriates.

When small portions of the common metals were heated in oxy- muriatic gas, they each inﬂamed, with the exception of gold, silver, and lead.

The product from arsenic was butter of arsenic highly volatile; that from antimony was butter of antimony easily fused, but crystallized when cold. Those from tellurium, zinc, and bismuth, were very similar to the preceding.