British scientist <a href="https://en.wikipedia.org/wiki/Joseph_Priestley" id="mwcg" rel="mw:WikiLink" title="Joseph Priestley">Joseph Priestley</a> discovers <a href="https://en.wikipedia.org/wiki/Oxygen" id="mwcw" rel="mw:WikiLink" title="Oxygen">oxygen</a> gas, corroborating the prior discovery of this element by German-Swedish chemist <a href="https://en.wikipedia.org/wiki/Carl_Wilhelm_Scheele" id="mwdA" rel="mw:WikiLink" title="Carl Wilhelm Scheele">Carl Wilhelm Scheele</a>.