such as John von Neumann, Enrico Fermi, and Hans Bethe. Following the radiation implosion idea offered by Teller and Ulam early in 1951, the focus of the work was on this new design idea. In June 1951, Ford returned to Princeton to continue the H-bomb work there at Wheeler's Project Matterhorn. Much of Ford's work was concerned with writing programs and doing calculations related to thermonuclear burning, first using human "computers" with desk calculators, then IBM card-programmed calculators (CPCs), and later, with Project Matterhorn, the SEAC computer at the National Bureau of Standards in Washington, DC. A SEAC calculation, programmed by Ford with the assistance of John Toll and the guidance of John Wheeler, provided the final predicted yield of 7 megatons for the Mike test on November 1, 1952. The actual yield was approximately 10 megatons. "I was aware of the fact that Oppenheimer was expressing opposition to the development of the H-bomb, for various reasons, from technical to moral. But I was also an accidental participant in what may have been the critical moment in changing his point of view. In June of '51 there was a meeting of the General Advisory Committee of the Atomic Energy Commission [actually a broader gathering that included the GAC] meeting at the Institute for Advanced Study. They were meeting in a first floor room on, if I remember correctly, a Sunday morning. Maybe it was a Saturday morning. It was a weekend. [It was Sunday, June 17.] Wheeler was scheduled to make a presentation on the latest results of our calculations on the CPC in New York. I was working every night, all night, that week prior to that meeting trying to get the latest and best results that we could."The night prior to this meeting at the Institute for Advanced Study, I took a morning train down from New York with the latest results, went over to the Matterhorn building, got out a very large piece of paper, maybe about two feet by three feet in size, a large rectangle of paper, and sketched out a graph showing our latest calculation of thermonuclear burning, still very crude of course, because of those calculations, yet extremely encouraging. I then rolled up this large graph and drove over to the Institute and walked up to the first-floor window of the room where the meeting was in progress and either rapped gently on