...Joseph Priestley, working independently around the same …
Years: 1774 - 1774
...Joseph Priestley, working independently around the same time Scheele is investigating air, recognize those of its components now known to be oxygen and nitrogen.
Priestley, who independently discovers fire air in 1774 by the thermal decomposition of mercury dioxide, publishes his findings in the same year, three years before Scheele publishes.
