The Royal Society Conversaziones were biannual social evenings at which distinguished guests could learn about the latest scientific developments. The Conversazione in May 1952 featured an object that came to be called King Arthur's Table. It was a planetary equatorium, made in Cambridge's Cavendish Laboratory at the behest of Sir Lawrence Bragg. Conceived by the historian of science Derek de Solla Price as a huge, tangible realization of Chaucerian astronomy, it was displayed at the new Whipple Museum of the History of Science, discarded, stored incognito, catalogued with that whimsical name, and finally re-identified in 2012. This article examines the biography of that object and, through it, the early, inchoate years of the discipline of history of science in Cambridge. The process of disciplinary establishment involved a range of actors beyond well-known figures such as Herbert Butterfield and Joseph Needham; the roles of Price and Bragg are highlighted here. Study of these individuals, and of the collaboration that brought about the reconstruction, reveals much about the establishment of a discipline, as well as changing scholarly and curatorial attitudes towards replicas.