446 Miscellaneoui

a different kind of substance from ibis

process.

9. Remarks on the Article Gas in the nen)Edition of Mr . Macquer’j Didlionaryof Chemiftry .

That excellent chemist, and most per-spicuous of writers, Mr. Macquer, has, ina new edition of his valuable EiSlionary,given a large article on the subject of thedifferent kinds of air, under the article gas,which I think very judicious, and useful inmost respects, as well as highly flattering tomyself. But as he seems to me to have madea few mistakes, I think I shall oblige him,and others, by endeavouring briefly to pointthem out.

He agrees with Mr. Lavoisier in sup-posing that phlogiston, combined with com-mon air, converts it into fixed air, p. 260,292, &c. and he imagines, that I supposeair to be injured by a mixture of fixed air,and that plants restore noxious air by im-bibing that fixed air, p. 293. Agreeably tothis idea, which runs through the whole

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