Page:Proceedings of the Royal Society of London Vol 1.djvu/441

Rh acid; but sublimed unaltered in carbonic, sulphureous, and muriatic acid gases.

In those instances where the salt was decomposed, the products were carbonic and muriatic acid gases. It is remarkable, that in the formation of this ammoniacal salt, the new gas combines with as much as four times its bulk of ammoniacal gas.

Tin, zinc, antimony, or arsenic, heated in this gas, combine with the chlorine, forming the usual compounds, and extricate carbonic oxide. The decomposition thus effected is completed in a few mi- nutes, but without explosion or ignition. Nor was even the action of potassium violent, although the decomposition was more complete ; since the carbonic oxide itself was decomposed, and carbon deposited. When the white oxide of zinc was employed instead of the metal, the gas that remained was found to be carbonic acid.

Sulphur or phosphorus might be sublimed in this gas without ef- fecting any change upon it. Neither did hydrogen or oxygen singly produce any eﬂect by means of the electric spark; but when both were mixed in due proportion of two parts hydrogen with one oxy- gen to two of the gas, an explosion took place, with the formation of muriatic acid and carbonic acid.

The power of 'this gas as an_acid is such as to decompound dry sub- wrbonate of ammonia; and its power of saturation is so remarkable, that the quantity of ammonia, which was not saturated by two mea- sures of carbonic acid, became fully saturated by only one measure of the new gas, which had extricated those two measures.

For the formation of this gas, it is absolutely necessary that its constituents should be in a state of perfect dryness, otherwise it will be mixed with carbonic acid and muriatic acid, in proportion to the quantity of moisture present; for if water he admitted to it, the whole is decomposed.

If they be mixed in a receiver previously exhausted, the direct light of the sun is not necessary ; daylight alone is sufﬁcient to unite them in less than twelve hours. But when they are mixed over mercury, then it is requisite to expose them immediately to bright sunshine; for otherwise the chlorine is absorbed by the mercury, and carbonic oxide alone remains.

The author also has endeavoured to unite these gases in an earthen- ware tube heated to redness, but without success.

The specific gravity of the gas has not been dimctly measured, but is inferred from the diminished bulk which it has been observed to occupy, and the known weights of the two gases which compose it. From these data, 100 cubic inches of gas are estimated to weigh 105'97 grains.

The relative afﬁnities of chlorine for carbonic oxide or for hydrogen, and of carbonic oxide for chlorine or for oxygen, appeared to the author to be ver}r nicely poised.

Hydrogen does not decompose the new gas, neither does carbonic oxide decompose muriatic gas ; and further, if equal parts of chlorine, of hydrogen, and of carbonic oxide, be mixed and exposed to light,