The Wollaston/Chenevix controversy over the elemental nature of palladium: A curious episode in the history of chemistry

Summary

In the course of his chemical investigation of crude platina ore, William Hyde Wollaston in 1802 isolated and characterized the metal palladium. In early 1803, he chose to make known his discovery by offering small samples of the metal for sale through a small shop in London. In the notice advertising the properties of the new metal, no information was given as to its source nor to its discoverer. The unique properties of the metal, and the secrecy surrounding its discovery, led the Irish chemist Richard Chenevix to question the elemental nature of the new metal. His hasty but extensive investigation of the chemical properties of palladium convinced him that it was no more than an alloy of platinum and mercury, and he denounced the discovery as fraudulent. The president of the Royal Society, Joseph Banks, was drawn into the resulting furore, and correspondence between him and Chenevix reveals involved plans to obtain the identity of the palladium discoverer. The controversy is viewed as a significant episode in the continuing debate in the chemical community over the operational definition of a chemical element, and although Chenevix's concern over the growth in the number of new elements was justified, his choice of palladium as a test case was an unfortunate one, for his claim that the metal was an alloy was found to be erroneous. Motives for the actions of both Chenevix and Wollaston are sought, and the judgement that their careers were damaged by the incident is questioned.