The radius of destructiveness by the blast of a bomb with a thousand times the energy of the A-bomb will be only ten times greater, since the increase goes by the cube root of the energy. The radius of total destruction by blast in Hiroshima was one mile. Therefore the radius of a superbomb a thousand times more powerful will be ten miles, or a total area of 314 square miles. A bomb a million times the power of the Hiroshima bomb would require 1,000 tons of deuterium. Such a super-superduper could be exploded at a distance from an abandoned, innocent-looking tramp ship. It would have a radius of destruction by blast of 100 miles and a destructive area of more than 30,000 square miles. The time may come when we shall have to search every vessel several hundred miles off shore. And the time may be nearer than we think. The radius over which the tremendous heat generated by a bomb of a thousandfold the energy would produce fatal burns would be as far as twenty miles from the center of the explosion. This radius increases as the square root, instead of the cube root, of the power. The Hiroshima bomb caused fatal burns at a radius of two thirds of a mile. The effects of the radiations from a hydrogen bomb are so terrifying that by describing them I run the risk of being branded a fearmonger. Yet facts are facts, and they have been known to scientists for a long time. It would be a disservice to the people if the facts were further denied to them. We have already paid too high a price for a secrecy that now turns out never to have been secret at all. I can do no better than quote Albert Einstein. “The hydrogen bomb,” he said, “appears on the public horizon as a probably attainable goal.... If successful, radioactive poisoning of the atmosphere, and hence annihilation of any life on earth, has been brought within the range of technical possibilities.” What Dr. Einstein meant by “radioactive poisoning of the atmosphere, and hence the annihilation of any life on earth,” was explained in realistic detail by such eminent physicists as Dr. Bethe, Dr. Leo Szilard, Dr. Edward Teller, and others. All of them may even now be engaged on work on the hydrogen bomb. Here is how “poisoning of the atmosphere” may result from the explosion of a hydrogen bomb: Tremendous quantities of neutrons, which can enter any substance in nature and make it radioactive, are liberated. In the case of a deuterium bomb, one eighth of the mass used—125 grams per kilogram—is liberated. In the case of a deuteron-tritium bomb, fully one fifth of the mass—200 grams per kilogram—is released, while in a bomb using pure tritium, fully one third of the mass—333 grams per kilogram—is liberated as free neutrons. There are 600,000 billion billion neutrons in each gram, each capable of producing a radioactive atom in its environment. The neutron is one of the two building blocks of the nuclei of all atoms.