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METHODS OF OBTAINING NITROGEN GAS.

acid. It is a component part of all animal substances, and com-municates to them their most distinctive characters. It was dis-covered by Dr. Rutherford of Edinburgh.

Nitrogen gas has been found by Priestley in the Bath waters,and by Pearson in the Buxton waters.

METHODS OF OBTAINING NITROGEN GAS.

Nitrogen gas may be obtained by various means. For in-stance, it has been long since ascertained that air which hasserved the purposes of combustion and respiration, is no longerproper for these uses. Chemists have availed themselves of thiscircumstance in order to obtain nitrogen gas in the followingmanner.

1. Make a quantity of sulphuret of potash or sulphuret of ironinto a paste with water, and place the mixture in a saucer or plateover water, on a stand raised above the fluid; then invert overit a jar or bell-glass, and allow this to stand for a day or two.The air contained in die bell-glass will gradually diminish, aswill appear from the ascent of the water, until only about threefourths of its original bulk remain.

When no further diminution takes place the vessel containingthe sulphuret must be removed, and die remaining air will befound to be nitrogen gas.

Rationale. ...The moistened sulphuret of potash has a greataffinity to oxigen, it attracts and separates it from the atmosphe-ric air, and the nitrogen gas is left behind; the sulphur is duringthe experiment converted into sulphuric acid, which unites to thealcali and forms sulphate of potash. The water with which thesulphuret is moistened likewise undergoes a decomposition, asshall be more fully proved in another place.

2. Nitrogen gas may likewise be obtained from fresh animalsubstances. For this purpose cut a piece of lean muscular fesliinto small pieces, introduce them into a retort and pour over them