Dutch chemist Martinus van Marum (1750–1837) discovered ozone around the year 1785, while conducting experiments with electricity. As many high school science students now do, van Marum smelled a distinctive odor while working with oxygen and electricity. Van Marum, who is also credited with discovering carbon monoxide, did not, however, identify the source of the odor as a unique gas molecule. It was not until 1840 that German-Swiss chemist Christian Friedrich Schönbein (1799–1868) correctly identified ozone as a gas, which he named after the Greek ozein, meaning “smell.” Finally, Swiss chemist J.L. Soret worked out its chemical structure as being a molecule consisting of three bonded oxygen atoms (O3).