Page:Proceedings of the Royal Society of London Vol 1.djvu/496

Rh Sulphuric and nitric acids which, according to the ﬁrst supposition, are inﬂammable bases combined with oxygen and water, when acted upon by ammonia. yield water, but ﬂuoric acid in combining with ammonia gives out no water. .

Sulphate of ammonia, by the action of potassium, yields sulphur and ammonia; and in the same manner nitrate of ammonia yields its base azote, with ammonia. But when ﬂuate of ammonia is acted upon by potassium, the only product beside ammonia is hydrogen, just as in the action of potassium upon muriate of ammonia, which yields only hydrogen and ammonia. In the latter case chlorine combines with the potassium; and it would appear that a similar base is contained in the ﬂuate of ammonia.

By the voltaic battery also, hydrates of such bodies as are known to contain oxygen, as sulphuric acid,hydrophosphorous acid, and nitric acid,- all yield oxygen at the positive wire, and. at the negative they give out their base, or a suboxide, along with hydrogen.

The strong action of ﬂuoric acid on almost all bodies, occasioned considerable diﬂiculty in attempting to collect the products of its electrization. But in a tube of horn silver, when it was electriﬁed by a wire of platina at the positive pole, the wire was covered with a chocolate-coloured powder, but no oxygen was extricated.

When a piece of plumbago was placed as the positive conductor in ﬂuoric acid, it was quickly destroyed, and a subﬂuate of iron was deposited at the negative surface, the ﬂuid becoming turbid and black.

These and other phenomena of electrization appear to the author not favourable to the supposition ofﬂuoric acid consisting of an inﬂammable base combined with oxygen; but to be best explained by supposing it to be, like muriatic acid, composed of hydrogen, which appears at the negative pole, and a peculiar principle to be termed ﬂuorine, which, like chlorine, is negative, and is attracted by the positive pole, and in general combines with the metal, which is there exposed to its action.

If, then, according to this supposition, we assume that ﬂuates are combustibles united with ﬂuorine, this principle cannot be obtained separate by means of any other combustible, as these will only form new compounds with it; but we may hope to effect the separation by means of oxygen or chlorine, as these in certain cases separate each other. And since the ﬂuates of silver, mercury, and potash, are decomposed by muriatic acid, the author exposed these compounds also to the action of chlorine, in the hope that ﬂuorine might by that means he disengaged.

But though these ﬂuates were each decomposed, the matter separated from them acted upon the vessels containing them with too much energy to be exhibited in a separate state.

There seems, however, says the author, great reason to suppose that a particular principle is separated from them analogous to chlorine, and that when it can he obtained separate, it will be found to he a gaseous body.

He estimates the number which should represent ﬂuorine at less