LARDNER, Dionysius, British physicist, born in Dublin, Ireland, 3 April, 1793; died in Paris, France, 29 April, 1859. After spending four years in the office of his father, a solicitor, he entered Trinity college, Dublin, gained many prizes in mathematics and metaphysics, was graduated in 1817, and continued a resident member of the university till 1827. During his college career he evinced an extraordinary aptitude for mathematical studies. He took orders, and was for some time chaplain at his college, but subsequently desisted from clerical functions. Upon the establishment of the London university he accepted the professorship of natural philosophy and astronomy, to which chair he was appointed in 1828. In 1840 he eloped with the wife of an officer in the army and came to the United States. He was sued for damages, and a verdict of £8,000 was entered against him. He married this lady after her husband's death. During" five years' residence in this country he delivered in the chief cities a series of lectures, which were published and have passed through many editions. On his return to Europe in 1845 he settled in Paris, where he resided until his death. He published "Popular Lectures on the Steam-Engine" (London, 1828), edited the "Cabinet Cyclopaedia" (134 vols., 1830-'44), to which he contributed numerous articles, and was the author of many other works on scientific and technical subjects, including hand-books on physical science (1851-'6).