PROOFS OF THE PROPERTIES OF OXIGEN GAS.

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If the phosphorus is weighed before the experiment, and thequantity of oxigen gas has been also ascertained, the weight ofthe produced acid will be found equal to the sum of the weightsof die phosphorus consumed and oxigen absorbed, if the experi-ment has been conducted carefully. Forty grains of phosphorusabsorb generally sixty-five of oxigen.

If the oxigen gas be pure, the residuum after combustion is aspure as die gas employed; this proves that nothing could escapefrom the phosphorus capable of altering the purity of the oxigengas, and that the only action of the phosphorus is to separate theoxigen from the caloric with which it was before united.

This property of being convertible into an acid belongs to allcombustible bodies; hence die combination of oxigen with sucha body is called origination.

Experiment II.

Comlustion of sulphur in oxigen gas.

This experiment is best performed by filling a large receiverwith oxigen gas, in the water-apparatus, and removing it bymeans of a flat dish into the mercurial trough, taking care toleave a little water over the mercury. When this is done put asmall piece of sulphur into a copper ladle, set fire to it by meansof a candle and blow-pipe, and introduce it into the gas. Thesulphur will burn with a beautiful blue flame, when the fumeshave disappeared, the water over the mercury will be found tohave an acid taste, it will turn blue vegetable colours red, andeffervesce with carbonated alcalies. It is therefore an acid, andas it is composed of sulphur and oxigen it is called sulphuricacid. If the respective quantities of gas, sulphur, and water,have been previously ascertained, the water will be found tohave increased in weight, as much as the sum of the weights ofthe sulphur and oxigen consumed.