One of the creators of the atomic bomb recalls its building and its effect both on its targets and on the world at large. Serber (1909-97) grew up in a hotbed of Jewish intellectualism in Philadelphia. The author’s reminiscences of his early days include his first car (a Model T Ford), college summer jobs, and his good luck in applying to graduate school at Wisconsin, where he managed to get an assistantship (a rarity in 1930). After meeting Robert Oppenheimer at a physics seminar, he took a position as his assistant; the association with “Oppie” eventually led him to work on the first atomic bomb. (He was the first person Oppenheimer invited to join the Manhattan Project.) Serber offers an insider’s perspective, including his belief that Einstein’s famous letter to Roosevelt urging research on nuclear fission actually delayed the bomb project nearly a year. He reveals that the concept of the thermonuclear bomb was already on the drawing board by July of 1942, when Edward Teller suggested it in a meeting and everyone promptly turned to the new problem--despite the fact that the atomic bomb had not yet been built. But after the Trinity test, the atom bomb was a reality; Serber was on the team that assembled the bombs dropped on Japan. The book reprints his letters of the time, revealing his belief that he had done what was necessary to end the war; then his accounts of visits to the target cities, to view the destruction firsthand and to measure the blasts’ effects. After the war, he fell under the same cloud of suspicion as his mentor Oppenheimer, but managed to clear himself and went on to hold major appointments, including direction of the Brookhaven National Laboratory. Co-author Crease (The Second Creation, 1986) contributes a preface. An extremely readable memoir by a man who was on the frontiers of physics for half a century.