Dictionary of National Biography, 1885-1900/Keogh, John (1650?-1725)
KEOGH, JOHN (1650?–1725), Irish divine, born at Clooncleagh, near Limerick, about 1650, was son of Denis Keogh, of an old Irish family, which had lost its possessions in the Cromwellian wars, by his wife, the widow of a clergyman named Eyres. His mother's maiden name was Wittington. Keogh entered Trinity College, Dublin, in 1669, and proceeded M.A. in 1678. He obtained some reputation for his skill in mathematics, was appointed to a living by his kinsman, John Hudson, bishop of Elphin, and settled down to a scholar's life at Strokestown, co. Roscommon. The prebend of Termonbarry in the church of Elphin was conferred on him in February 1678, and he appears for some time to have kept a school and prepared pupils for Dublin University (Vindication of Antiquities of Ireland, p. 140). His favourite studies seem to have been Hebrew and the application of mathematics to the solution of mystical religious problems. Among his works was ‘A Demonstration in Latin Verse of the Trinity,’ which ‘he was often heard to say was as plain to him as two and three make five.’ Keogh's son, during a visit to London, showed this work to Sir Isaac Newton, ‘who seemed to approve of it mighty well.’ In his ‘Scala Metaphysica’ Keogh demonstrated mathematically ‘what dependence the several degrees of beings have on God Almighty, from the highest angel to the lowest insect.’ A large number of other ‘ingenious treatises’ from his hand were unfortunately destroyed by an accidental fire at his residence; but his ‘Hebrew Lexicon,’ a book ‘De Orthographia,’ Latin and Greek grammars, and an ‘Analogy of the Four Gospels’ still exist in manuscript in Trinity College Library. He died in 1725. Keogh married in 1679 Avis Clopton, daughter of Dr. Rous Clopton, of the old Warwickshire family. He had twenty-one children.
The second son, John Keogh, D.D. (1681?–1754), entered the church, and after acting for some time as chaplain to James King, fourth lord Kingston, obtained the living of Mitchelstown, co. Cork. He was the author of three curious works: 1. ‘Botanologia Universalis Hibernica’ (a list of medicinal plants growing in Ireland), Cork, 1735 (see Pulteney, Progress of Botany, ii. 201, cf. Addit. MS. 25586). 2. ‘Zoologica Medica Hibernica,’ Dublin, 1739. 3. ‘A Vindication of the Antiquities of Ireland,’ Dublin, 1748. He married Elizabeth, daughter of Dr. Henry Jennings, a cousin of the Duchess of Marlborough, by whom he had three sons and three daughters. He died in 1754, at the age of seventy-three.
[Webb's Compendium of Irish Biog.; Walker's Hibernian Mag. 1778, p. 327; Cotton's Fasti, iv. 155; Account of the Keogh or MacEochaohs family in Vindication of the Antiquities of Ireland, Appendix.]