Physics in the 20th century has become something that even non-scientists know something about. Albert Einstein and some of the other greats have become household names, invoked almost as often as the names of deities. On the other hand, the purity and innocence of physics was forever changed by the development of the atomic bomb, causing a kind of dreadful fear of science in mainstream culture. C.P. Snow gives a wonderful picture of how it all came about, up to 1980. His anecdotes and personal sketches of the major figures read like short biographies of old friends. He shows how atomic weapons were developed, each step building on the previous ones, until the ultimate destruction became inevitable. He also writes of hope for the future: hope in new minds and new discoveries. The book is well-illustrated with black and white photographs and drawings and it is not too long to read in a couple of evenings.