Cockcroft was born in Todmorden, England, on May 27, 1897, the son of a textile manufacturer. After completing secondary school at Todmorden in 1914, he entered Manchester University. He left the university after only one year to join the British army and enter World War I. He survived some of the worst battles of the war and returned to take a job at the Metropolitan Vickers Electrical Company. Officials at Vickers encouraged him to return to college and, in 1924, he earned his bachelors degree from St. John's College, Cambridge. After graduation, he joined Ernest Rutherford's (1871-1937) research team at the Cavendish Laboratory. While at the Cavendish, Cockcroft met the Russian physicist George Gamow (1904-1968) who outlined a new theory about particle bombardment. Gamow explained that his calculations showed that subatomic particles with a relatively modest amount of kinetic energy had a small, but significant, probability of entering atomic nuclei and causing...