Depblogifticated Air. 239

common fire, urged with a pair of bellows,the residuum was as good as common air,or rather better. This air came over veryturbid.

Manganese yielding dephlogisticated airwithout the help of any acid, it might bethought more proper for the production ofair with that assistance, as minium is withrespect to the nitrous acid. I thereforetried it on the 15th of April, when to oneounce of this substance, which had been,kept red hot a long time on the 10th ofNovember preceeding, I put some oil of'vitriol, which it imbibed eagerly ; andthen got from it about twelve ounce mea-sures of air, the whole of which was fixedair, except about one ounce measure, whichwas about as good as common air. In thisexperiment I believe I made use of a gunbarrel, so that probably more, and betterair would have been procured in a glassvessel.

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