The discovery of oxygen.

  • Scheele, Carl Wilhelm, 1742-1786.
Date:
1894
Catalogue details

Licence: Public Domain Mark

Credit: The discovery of oxygen. Source: Wellcome Collection.

Provider: This material has been provided by UCL Library Services. The original may be consulted at UCL (University College London)

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    treatise on arsenic communicated to the Royal Swedish Academy of Sciences, that this poisonous substance is compounded of a peculiar acid and an inflammable substance. I also shewed in the same treatise how this acid can be sublimed into ordinary arsenic simply by continued heat; and although I clearly perceived the reason for this, even at that time, still I was unwilling to mention it there in order to avoid prolixity. I placed some of this fixed acid of arsenic in a small retort with a bladder attached, for distillation. When the acid had gone into fusion, and glowed brightly, it began to boil; during this ebullition arsenic rose into the neck and the bladder became expanded; I continued with this heat as long as the retort would hold out. The air collected was likewise fire-air. In the same treatise I made mention of a peculiar explosion which took place in the distillation of zinc with the acid of arsenic. How clear, how mani- fest does the explanation of this phenomenon not become when one is satisfied that in this case fire-air is present in the retort in its greatest purity, and the zinc is in red hot fusion ? What more is necessary for its ignition ? I have very often regarded with pleasure the brightly glowing sparks which are produced in a retort by heat alone, during the reduction of metallic calces, when only a very little coal dust is mixed along with it. We shall now see whether this fire-air is not the same air which had been lost without fire (§§ 8-15), and with nre (§§ 17-23)- 42. First Experiment—I filled a bottle which was capable of holding 16 ounces of water with pure fire-air according to the method which is described in § 30, letter e. I placed the bottle, inverted, in a glass which was filled with a solution of liver of sulphur. The solu- tion rose a little into the bottle hour by hour, and after the lapse of 2 days the bottle was filled with it.