A lucid and stimulating description of the birth and growth of atomic science, this book by a well-known nuclear physicist with a flare for popularizing his specialty, presents a model example of how a foundation was laid and a new branch of physics built upon it. The author takes us back to the beginning of experimental atomic science when in 1895 Roentgen discovered and named the X-ray. From there he shows us how theory and experiment went hand in hand to open up investigation of the inner architecture of the atom. We witness the coining of the word ""radioactivity"" by the Curies, Rutherford's discovery of alpha and beta rays and true transmutation, Bohr's elucidation of atomic structure, Hahn's and Strassman's smashing of the uranium atom, Fermi's experiments that led to the first self-sustaining chain reaction and finally to the A-bomb and the H-bomb. Throughout there are clarifying explanations of how radioactive substances decay, what goes on inside the nucleus of the atom, how the atom releases its enormous energy, how atomic particles are used in the cyclotron and betatron, the versatility of the neutron, the use of radio-isotopes, the use of atomic energy as fuel, the fusion of hydrogen in the sun, and many other related phenomena. This is a valuable book for the interested layman, teacher and student. It makes clear all the fundamentals of atomic science in a way that should make it one of the first books to be consulted for a broad picture of the theoretical and technological development, and potentiality of nuclear physics.