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More than 5000 entries on the history, culture and life of Britain (published in 1993 by Macmillan, now out of print)
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Ernest Rutherford
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(1871–1937, kt 1914, baron 1931)
Physicist, born in New Zealand, whose researches on the atomic structure are the basis of modern nuclear physics. At the *Cavendish Laboratory in Cambridge (1895–8) and then at McGill University in Montreal (1898–1907) his early work was on radioactivity. He recognized with *Soddy in 1902-3 that radioactive substances are emitting rays while spontaneously transmuting into different elements, and thus formulated the concept of radioactive half-life; it was for his discoveries in this region that he received the Nobel prize for chemistry in 1908. Even greater work was to come, at the university of Manchester (1907–1919) and then back at the Cavendish, where he succeeded J.J. *Thomson as director.
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The turning point into the age of nuclear physics was Rutherford's perception in 1911 that there was a very dense positively charged nucleus at the heart of the atom, tiny compared with the size of the atom as a whole; its existence had been suggested to him by the mysterious rebounding from metal foil of just a few out of many alpha particles (helium nuclei), implying that the obstacle they had struck was small but heavy. In 1919 he achieved the first artificially induced nuclear reaction, bombarding nitrogen with alpha particles and releasing particles which he named protons. He next showed (1920) that the proton formed the entire nucleus of the hydrogen atom and in differing numbers was present in all other nuclei. The brilliant team headed by Rutherford at the Cavendish went on to make further advances in subatomic physics – notably *Chadwick's discovery of the neutron.
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