The Idea of the Chain Reaction
In 1933, Szilard fled to London and read an article by Ernest Rutherford which said atomic energy could not be used for practical purposes. Szilard did not believe this to be correct and so he began experimenting.  Beryllium and indium were attempted for making the reaction, but they failed.  He later accepted an offer to research at Columbia University in Manhattan, where he was soon joined by Enrico Fermi. Upon learning of nuclear fission, they figured uranium may be able to support a chain reaction. They were correct and they achieved neutron multiplication. Szilard is reported to have described the event with, "We turned the switch, saw the flashes, watched for ten minutes, then switched everything off and went home. That night I knew the world was headed for sorrow."(1)
(1) http://en.wikipedia.org/wiki/Leo_Szilard

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