FITZGERALD, GEORGE FRANCIS (1851-1901), Irish physicist, was born at Dublin on Aug. 3, 1851. He studied at Trinity college, Dublin, becoming a fellow in 1877. In 1879 he became tutor and in 1881 Erasmus Smith professor of natural philosophy at Trinity college, Dublin. He retained this post until he died on Feb. 21, 1901. FitzGerald started classes in experi mental physics at Dublin and developed the laboratories in spite of lack of encouragement. He had a wide knowledge of physics and was a brilliant speculator, his services as a critic of scientific work were very much in demand and he had a great influence on the men who worked under him. Fitzgerald's own work is mainly on radiation and electrical theory, most of his papers were published in the Proceedings of the Royal Dublin Society and because of this were not as well known as they deserved to be. One of his earliest and most important memoirs on the "Electromagnetic Theory of the Reflection and Refraction of Light" deals with the theoretical bearing of the magneto optical phenomenon known as the Kerr effect. He investigated the problem of electric radiation due to a variable current and pointed out that the oscillatory discharge of a condenser might be the means of producing electric radiation. Soon after this work appeared Hertz succeeded in producing electric waves ex perimentally. FitzGerald realized the importance of this work, he put himself in touch with Hertz and converted him to Max well's ideas. He wrote a memoir on the electro-magnetic effect due to the motion of the earth and he constructed a model of the aether.
While studying the results of the Michelson-Morley experiment FitzGerald worked out the change in shape of a body produced by its motion through the aether. This is now known as the Lorentz FitzGerald hypothesis. In conjunction with his pupils he carried out a number of investigations on the laws of polarization of Hertzian waves by reflection, on the detection of these waves and on the scattering of X-rays ; he tested the validity of Ohm's law for electrolysis. In addition to his scientific work FitzGerald was interested in education and it is largely through his efforts that technical education was established in Ireland. He was appointed a commissioner of national education in 1898 and a member of the Irish board of intermediate education in 1900. FitzGerald was a member and officer of many learned societies; he was awarded the Royal Society's Royal medal in 1899.
His papers, with an introduction, have been edited by Larmor under the title The Scientific Writings of the Late George Francis Fitz Gerald (1902) .