George Johnstone Stoney is best remembered in the history of science for introducing the term ‘electron’, which he did in a paper in the Transactions of the Royal Dublin Society in 1891. This was an important conceptual step leading to the eventual physical discovery of the electron by J.J. Thomson at Cambridge in 1897–1899.
Born at Oakley Park, near Birr, in Co. Offaly, he was educated at Trinity College Dublin. While studying for a Fellowship in Trinity, he was employed by the third Earl of Rosse as astronomical assistant at Birr Observatory. He was unsuccessful in the Fellowship examination, but in 1852 was appointed Professor of Natural Philosophy at Queen’s College, Galway (now NUI Galway). He became Secretary of the Queen’s University in 1857. This was the administrative body for the colleges at Belfast, Cork and Galway. He thus had to carry out much of his scientific work on an out-of-hours basis, and he made use of the laboratory and research facilities of the RDS for this purpose. He was elected to Fellowship of the Royal Society in 1861 and became Honorary Secretary of the RDS from 1871 to 1881 and Vice-President from 1881 to 1911.
Stoney established a fundamental set of mass, length and time units known as ‘Stoney units’ which are based on the gravitational constant, the speed of light and the charge of the electron. Although primarily known for his work in theoretical physics, Stoney had a practical turn of mind also, and he devised several new forms of scientific instruments. He published papers on the energy expended in propelling a bicycle; gearing for bicycles and tricycles; the possibility of prolonging the tones of a pianoforte (so as to produce an instrument with the quality of tone of the piano and the continuity of tone of the organ), all in the scientific journals of the RDS.
His interest in music was also demonstrated by his role in the introduction of recitals to the cultural programme of the Society. In 1893, Stoney left Dublin for London so that his daughters could have the opportunity of a university education, something not possible at the time in Dublin, but he continued to take a great interest in Irish third-level education. He died in 1911.
George Johnstone Stoney was the 1899 Boyle Medal Laureate.