April 14th, 1932: John Cockcroft and Ernest Walton focus a proton beam on lithium and bust its nucleus. The era of accelerator-based experimental nuclear physics is born. Ernest Rutherford, who first postulated the concept of atomic nucleus in 1910, had called for "a million volts in a soapbox" to advance nuclear research. Working in a vacant room at Rutherford's Cavendish Laboratory at Cambridge University, Englishman Cockcroft and Irishman Walton used spare parts along with some wood and nails to build the world's first nuclear-particle accelerator in 1929. At the heart of the Cockcroft-Walton generator, a system of capacitors and thermionic rectifiers upped the voltages to 600,000 volts. It wasn't a million volts, but it proved sufficient.
http://www.wired.com/science/discoveries/news/2008/04/dayintech_0414