THOSE who knew the University of Dublin twenty years ago will remember that the idol of the undergraduates and the hope of the older men was George Francis FitzGerald. He was of high intellectual lineage on both sides: his father was the most distinguished prelate in the Irish Protestant Church, and his uncles are men of large and original scientific achievement. His early education was conducted at home, in company with his two brothers, one (now professor of engineering at Belfast) a year older than himself, the other younger. He was good at physical science and all subjects requiring close observation, from his earliest years; and the ambition to become a master was soon aroused. The mathematical and physical tendency seems to have come mainly from his mother's side, his strong metaphysical bent from both sides of the family. In his student career he attained all the distinctions that lay in his path with an ease, and wore them with a grace, that endeared him to his rivals and contemporaries. On taking his first degree in 1871 he settled down, at twenty years of age, after the manner of the pick of the Dublin men, to a wide and independent course of reading with a view to a Fellowship. At that time vacancies were of very rare occurrence; so that it was not until 1877, on his second time of trying, that he attained the position of a Fellow of Trinity College. The examination in mathematical and physical science included papers on selected portions of the works of the great mathematical physicists; to a mind of the calibre of FitzGerald's, the early and intimate acquaintance which was thus promoted with the classical writings of Lagrange and Laplace, of Hamilton and MacCullagh, with their modes of thought as Well as the results that they won, must have formed the best possible foundation for a scientific career. A training which aims only at sound knowledge and established results may find a shorter path in the study of the latest text-books of the day; but if a man is to be a true leader he must be interested even more in the philosophy than in the facts of his science. It must have been of rare value to a maturing mind of keen temper to observe closely at first hand the lines of attack of the great masters of the past age on problems which were crystallising into knowledge. Acquaintance with the present state of science, however detailed and exact, assumes its full value as an instrument of progress only when it is accompanied by appreciation of the difficulties that had to be circumvented in order to reach it, and by observation of the way in which complete logical precision may have to be attained at the expense of temporary limitation. The subjects that were grouped around physical optics were approached in Dublin, in those days, through the study of MacCullagh's optical memoirs; these writings were based on a remarkable combination of keen analysis of the facts and direct application of the generalised dynamical methods of Lagrange, thus presenting all that interest of nascent scientific discovery which the same topics still retain in their wider connection with the general problem of the æther. Whatever may be the defects of MacCullagh's analysis, it had the saving merit that it put forward no claim to finality; its critical comparison and contrast with those of Cauchy and Neumann and Green, and the difficulties which its procedure suggested from a restricted dynamical point of view, were the very things with which a mathematical analyst might be impatient, but over which a mind constituted like FitzGerald's would eagerly brood. When the great Treatise of Maxwell, which threw a flood of light on these fundamental problems from an altogether novel source, came into hands thus prepared for its appreciation, it is not surprising that a main scientific interest became established for life.