AMMONIA.

30H

MRS. B.

It was discovered a few years since, by Ber-thollet, a celebrated French chemist, that it con-sisted of about one part of hydrogen to four partsof nitrogen. Having heated ammoniacal gasunder a receiver, by causing the electrical sparkto pass repeatedly through it, he found that itincreased considerably in bulk, lost all its alka-line properties, and was actually converted intohydrogen and nitrogen gasses.

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EMILY.

Ammoniacal gas must, I suppose, be veryheavy, since it expands so much when decom-posed ?

MRS. B.

Compared with hydrogen gas, it certainly is;but it is considerably lighter than oxygen gus>and only about half the weight of atmosphericalair. it possesses most of the properties of thefixed alkalies ; but cannot be of so much use inthe arts on account of its volatile nature. It is,therefore, never employed in the manufacture ofglass, but it forms soap with oils equally as wellas potash and soda: it resembles them likewisein its strong attraction for W'ater ; for which rea-son it can be collected in a receiver over mercuryonly.