"My dissertation examines the Franciscan engagement with medicinal alchemy between 1250 and 1360. I investigate the works of three generations of Franciscan alchemical and apocalyptic authors: Roger Bacon (ca. 1214/20-ca. 1292), Vitalis of Furno (1260-1327), and John of Rupescissa (ca. 1300-ca. 1366). Working across the disciplines of religious studies and the history of science, I demonstrate that the material process of alchemy inflected Christian conceptions of apocalypse, resurrection, and prophecy. Radical apocalypticism and religious alchemy share a defining characteristic. Both are concerned with manifesting spiritual truth on the physical plane. In the case of the Apocalypse, evil is neither an idea nor a concept, rather it is personified by Antichrist and his followers. The New Jerusalem was not merely a vehicle for spiritual reflection; it was a promise to the elect. Therefore, those who will be resurrected in body and inhabit the New Jerusalem will manifest heaven writ on earth. Alchemy represented an even more present possibility of literally distilling a heavenly reality. The alchemist's theoretical ability to create a post-resurrection body or to use the substance of heaven to cure every ailment, drive away demons, and bestow courage on enemies of Antichrist not only effaced the separation of heaven and earth, it offered unmediated access to divine power."