The discovery of oxygen, part 1. : experiments / by Joseph Priestley, LL.D. (1775).

  • Priestley, Joseph, 1733-1804.
Date:
1894
Catalogue details

Licence: Public Domain Mark

Credit: The discovery of oxygen, part 1. : experiments / by Joseph Priestley, LL.D. (1775). Source: Wellcome Collection.

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    pretty confident that the air within the bladder contained very little common, or any other kind of air. In this manner I proceeded to weigh dephlogisticated air., and at the same time nitrous air, and air phlogisticated with iron filings and hri/nstone, which 1 take for granted is the same thing with air phlogisticated by any other process. Idle following short table exhibits the result of all these experiments at one view. The bladder, filled with dwts. gr. phlogisticated air, weighed - - - - - 1 '^S nitrous air - - - -716 common air - - - - 7 17 dephlogisticated air - - - 7 19 The result agrees sufficiently well with my former observations, though they were not made with so much accuracy, viz. that both nitrous air, and air diminished by phlogistic processes, are rather lighter than common air; and it is consonant to this, that, in the present experiment, dephlogisticated air appears to be a little heavier than common air. Comparing these observations with that of the extreme 'lightness of inflammable air, ascertained by Mr. Cavendish, it should seem that the less phlogiston any kind of air contains the heavier it is, and the more phlogiston it contains the lighter it is; though this is by no means the case with solid substances, and indeed it is rather unfavourable to this hypothesis, that nitrous air should not be lighter than dephlogisticated air; for it should seem, by its property of phlogisticating common air, that it should itself contain a greater proportion of phlogiston. Also, in the above mentioned processes for making air, the more phlogiston there is in the substances moistened with spirit of nitre, the more certain it is that the produce will be nitrous air; as the less phlogiston they contain, the more certain it is that the produce will be pure air. D