Below (Colonel Tibbets), the city of Hiroshima lay sparkling in the sunlight that shone down on it through a ten-mile hole, in the clouds -- as though the god of war had provided a beacon for Little Boy to follow."" The unfortunate simile is indicative of the attitude that signals the atomic bomb as ""a totally new concept in weaponry"" and, in time, money and effort, ""history's greatest gamble."" As the narrative proceeds, as events overtake him, Mr. Hirschfeld abandons some of his more offensive overwriting and, more important, some of his equally offensive enthusiasm. The events are as expected; early experiments in Europe; emigration of scientists to the United States; alerting President Roosevelt to possible German nuclear attack and enlisting his assistance; progress of the Manhattan Project, including construction of dispersed facilities at Oak Ridge, Hanford and Los Alamos; composition of the technical and scientific team (with sympathetic if somewhat patronizing treatment of Oppenheimer); formation of the Air Force group, to deliver the bomb; the successful test explosion at Alomogordo; the decision to drop the bomb; the mission itself and its consequences for Hiroshima; continuing disagreement on the moral question. In anecdotes bridged with brief explanations, it's all here (except what happened to Col. Tibbets, afterward), but the subject requires a more sober, composed treatment than it receives.