Catalysing Chemical Correspondence

James Watt has already been established as a competent eighteenth-century chemist. His role as a chemical correspondent, however, has not been examined adequately. This chapter argues that through well-timed letters Watt circulated vital knowledge between two contemporary chemists, Joseph Black and James Keir. Two case studies in industrial chemistry—the production of alkali and the separation of plated metals—reveal Watt to be an active letter writer who initiated collaboration between business partners and communicated processes promptly. No mere passive conduit of information, Watt was a confidant who encouraged propriety in the manner of correspondence. He was a lynchpin between Black and Keir when the former was fearful of writing the latter, and he censured ill-timed disclosure of industrial secrets. This chapter concludes that future study of Watt’s epistolary exchanges with other chemists will establish more firmly his mediating role in chemical correspondence in the eighteenth-century Republic of Letters.