Dephlogisticated air (oxygen gas) discovered
Aire desflogistizado / aire de fuego (gas que sostiene la combustión)
- Date
- 1774 · confidence high
- Place
- Bowood House, Calne (Wiltshire), England
- Credited to
- Joseph Priestley; independently Carl Wilhelm Scheele (Uppsala)
- People
- 👤 Joseph Priestley1733–1804
- Field
- Matter & energy
⚠️ Disputed: the sources disagree.
What was discovered
Priestley obtains a gas by heating mercury oxide, in which a candle burns brightly and a mouse survives longer. Scheele had prepared it earlier (1771-72) as 'fire air'. This gas was key to overturning phlogiston.
Scheele discovered it first but published in 1777; Priestley published in 1775; Lavoisier interpreted it. It is catalogued here as the discovery of the gas's role in combustion, not as an element.
What it led to
- Lavoisier's theory of combustion
- Physiology of respiration
- Medicinal and industrial oxygen
Built on
- Black's pneumatic chemistry
- burning lens
Made possible
- oxyhydrogen blowtorch
- oxygen therapy