rHOSl’HORATED HIDKOBEN GAS.

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water, they explode in succession as they reach the surface ofthis fluid. It has an insupportable odour similar to that of putridfish. It is partly absorbable by distilled water freed from atmos-pheric air at low temperatures. Distilled water absorbs aboutone-fourth, and gives it out again without alteration by heat.Water containing atmospheric air decomposes it, when sufferedto stand w'ith it for some time. When exposed to vivid light, itdeposits phosphorus in a crystalline form.

METHODS OF OBTAINING PHOSPHORATEDHIDROGEN GAS.

J. Take a small retort, put into it one part of phosphorusand ten of a concentrated solution of potash or soda ; make themixture boil and receive the liberated gas over mercury; or if itbe intended for immediate use, it may be collected over water.

Rationale. ..In this experiment a decomposition of thewater takes place. Its oxigen unites to part of the phosphorusand forms phosphoric acid, which joins to the potash and formsphosphate of potash. The liberated hidrogen dissolves anotherpart of the phosphorus and becomes converted into phospho-rated hidrogen gas.

Remark. ..In thus preparing this gas, the body of the retortshould be filled as nearly as possible with the mixture, other-wise the first portion of gas which is produced inflames in theretort; a vacuum is formed, and the water forced up into theretort, and endangers the bursting of it.

2. Phosphorated hidrogen gas is also obtained, if by a directexposure to a strong heat we effect a combination of phosphorusand lime (see p. 105) and then throw this compound into water,a great quantity of phosphorated hidrogen gas will soon beformed, and may be collected in the usual manner over wateror mercury.

Rationale. ..The production of phosphorated hidrogen gasin this manner is analogous to the first, with the only difference