"[[[Henry Cavendish|H]e]] published in 1783, and, like all his other papers, the modest title... An Account of a New , conveyed a very imperfect idea of its contents. ...[I]t is ostensibly devoted to the explanation of an instrument for determining the proportion of oxygen in air, by observing the contraction which followed its mixture with a given volume of . Priestley, the first investigator of the properties of nitric oxide, had devised this process, but was too inaccurate a manipulator to make good use of it."