Ernest Rutherford was one of the pioneers of nuclear physics. He was the fourth of twelve children and won a scholarship to Canterbury College (New Zealand) when he was eighteen. He first worked on the magnetism of iron by high-frequency discharges (1894) and later made a sensitive radiowave detector in the same year that Guglielmo Marconi began his radio experiments. In 1895 he travelled to England was admitted to the Cavendish Laboratory in Cambridge, where he made the first successful wireless radio transmission over a distance of two miles. Rutherford was the first research student at Cambridge to work with J. J. Thomson, and under his direction he soon focused his thoughts on atomic physics, investigating the effect of X-rays on the discharge of electricity in gases. It was at Cambridge that he discovered the three types of nuclear radiation (alpha, beta and gamma rays) after noticing that there were different types of radiation, each with different penetrating power.
In 1898 Rutherford began work at the University of Montreal and with Frederick Soddy (who later discovered isotopes) developed the theory of atomic disintegration, accounting for the energy that radiates spontaneously from uranium. They showed that this was due to the breakdown of its atoms to form a new element. It was for this work that Rutherford was awarded the Nobel Prize for Chemistry. In 1907, he returned to Cambridge and, during his work on nuclear physics, asked his two research students, Hans Geiger and Ernest Marsden, to investigate the scattering of alpha-particles from a thin piece of gold foil. To Rutherford's astonishment, they found that some of the alpha-particles were sometimes deflected backwards from the gold foil. Using these results, Rutherford proposed a new model of a typical atom in which electrons orbit a tiny, charged nucleus, and he used this model to derive a formula that described the scattering of alpha-particles by atomic nuclei. Geiger and Marsden performed further experiments that lent strong support to this description and in 1911 Rutherford formally proposed the nuclear model of the atom, which has since formed the basis of successful atomic models.
During the First World War, Rutherford worked on submarine detection. Directly afterwards, he returned to nuclear studies and he showed in 1919 that alpha-particles cause nitrogen nuclei to disintegrate and form hydrogen and oxygen nuclei (this was the first nuclear reaction to be directly observed). Among his later achievements, he predicted the existence of the neutron, which was later discovered by his colleague James Chadwick. Rutherford was a forceful and extremely competitive physicist who strove successfully to be the leader of his field. He also possessed a modicum of musical talent and was often heard humming 'Onward Christian Soldiers' while working in the laboratory.
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