Jim Baggott 
Atomic : The First War of Physics and the Secret History of the Atom Bomb 1939-49 [EPUB ebook] 
The First War of Physics and the Secret History of the Atom Bomb 1939-49

Spanning ten historic years, from the discovery of nuclear fission in 1939 to 'Joe-1′, the first Soviet atomic bomb test in August 1949, Atomic is the first fully realised popular account of the race between Nazi Germany, Britain, America and the Soviet Union to build atomic weapons.
Rich in personality, action, confrontation and deception, Jim Baggott’s book tells an epic story of science and technology at the very limits of human understanding.