Volume 2

Experiments and observations on different kinds of air, and other branches of natural philosophy, connected with the subject ... / being the former six volumes abridged and methodized, with many additions. By Joseph Priestley.

  • Priestley, Joseph, 1733-1804.
Date:
1790
Catalogue details

Licence: Public Domain Mark

Credit: Experiments and observations on different kinds of air, and other branches of natural philosophy, connected with the subject ... / being the former six volumes abridged and methodized, with many additions. By Joseph Priestley. Source: Wellcome Collection.

    137/496 (page 121)
    firft, and nearly three times its bulk of nitrous air made very little addition to its original dimenfions ; fo that this air was exceedingly pure, and better than any that I had procured before. One quantity of red lead, which I procured, had a yeilowifh caft, and had in it feveral pieces intirely yellow. I tried it with the burning lens in quick- filver, and found that it yielded very little air, and with great difficulty ; requiring the application of a very intenfe heat. With an equal quantity of ni- trous air, a part of this air was reduced to one half of its original bulk, and three meafures and a half faturated it. The air, therefore, was very pure, and the quantity that it yielded being very fmall, it proved to be in a very favourable fliate for afcer- taining on what circumftances its acquiring this air depended. My objeft now was to bring this red lead, which yielded very little air, to that ftate in which other red lead had yielded a confiderable quantity j ahd taking it, in a manner, for granted, in confequence of the reafoning intimated above, that red lead muft imbibe from the atmofphere fome kind of acid^ in order to acquire that property, I took three feparate half ounces of this freffi made red lead, and moiften- cd them till they made a kind of pafte, with each of the three mineral acids, viz. the vitriolic, the ma- rine, and the nitrous i and as I intended to make