(From a talk on the hydrogen bomb, March 27, 1950, at Town Hall, Los Angeles, by PROFESSOR ROBERT F. BACHER, head of the Physics Department, California Institute of Technology. Professor Bacher served as the first scientific member of the Atomic Energy Commission and was one of the major architects of the atomic bomb at Los Alamos, New Mexico.) THE HELL BOMB I THE TRUTH ABOUT THE HYDROGEN BOMB I first heard about the hydrogen bomb in the spring of 1945 in Los Alamos, New Mexico, where our scientists were putting the finishing touches on the model-T uranium, or plutonium, fission bomb. I learned to my astonishment that, in addition to this work, they were already considering preliminary designs for a hydrogen-fusion bomb, which in their lighter moments they called the “Superduper” or just the “Super.” I can still remember my shock and incredulity when I first heard about it from one of the scientists assigned to me by Dr. J. Robert Oppenheimer as guides in the Dantesque world that was Los Alamos, where the very atmosphere gave one the sense of being in the presence of the supernatural. It seemed so fantastic to talk of a superatomic bomb even before the uranium, or the plutonium, bomb had been completed and tested—in fact, even before anybody knew that it would work at all—that I was inclined at first to disbelieve it. Could anything be more powerful, I found myself thinking, than a weapon that, on paper at least, promised to release an explosive force of 20,000 tons of TNT? It was a screwball world, this world of Los Alamos, I kept saying to myself, and this was just a screwball notion of my younger scientific mentors. So at the first opportunity I put the question to Professor Hans A. Bethe, of Cornell University, one of the world’s top atomic scientists, who headed the elite circle of theoretical physicists at Los Alamos. Dr. Bethe, I knew, was the outstanding authority in the world qualified to talk about the subject, since he was the very man who first succeeded in explaining how the fusion of hydrogen in the sun is the source of energy that will make it possible for life to continue on earth for billions of years. “Is it true about the superbomb?” I asked him. “Will it really be as much as fifty times as powerful as the uranium or plutonium bomb?” I shall never forget the impact on me of his quiet answer as he looked away toward the Sangre de Cristo (Blood of Christ) mountain range, their peaks turning blood-red in the New Mexico twilight. “Yes,” he said, “it could be made to equal a million tons of TNT.” Then, after a pause: “Even more than a million.” The tops of the mountains seemed to catch fire as he spoke.