Jack Parsons, an engineer who had been one of the founders of the Jet Propulsion Laboratory in Pasadena. Parsons was a member of the Ordo Templi Orientis, a group associated with the occultist Aleister Crowley, to whom he sent money. He was also a science fiction fan, and Heinlein, Williamson, and Cartmill all attended meetings of the temple, which de Camp called “a conspiracy to seize control from the extroverts.”
