JACK, THOMAS, an eminent scholar of the sixteenth century, was master of the Grammar school at Glasgow, which situation he relinquished in 1574, to become minister of Eastwood parish, near Paisley. In 1592 appeared his ‘Onomasticon Poeticum,’ a sort of dictionary in blank Latin verse, of the localities of classical poetry, which is now very scarce. From the dedication, it appears that the work was revised by Buchanan. In 1582 Jack was minister of Rutherglen, and as such was one of those who opposed the election of Robert Montgomery as archbishop of Glasgow. On the 22d May of that year he and Mr. Thomas Smeton went to Edinburgh to inform the presbytery that Mr. Montgomery had transgressed the act of assembly, and craved that he might be excommunicated. In 1590 he was a member of the General Assembly. He died in 1596.

JACK, GILBERT, a learned metaphysician and medical writer, was born at Aberdeen in 1578. He studied under Robert Howie, who, in 1593, was made principal of Marischal college, on its erection into a university. It is stated by Freher, that he attended the philosophy class at St. Andrews, taught by Robert Hay, an eminent theologian, at whose advice he afterwards pursued his studies at the colleges of Herborn and Helmstadt, on the Continent. In 1604, a period when almost every college in Europe numbered a Scotsman among its professors, he was appointed to the chair of philosophy in the university of Leyden, where, having studied medicine, he took his degree of M.D. in 1611. In 1612 he published ‘Institutions Physicae, Juventutis Lugdunensis Studiis potissimum dicatae,’ reprinted with notes in 1616. In 1624 appeared his ‘Institutiones Medicinae,’ and shortly afterwards he was offered the chair of civil history at Oxford, which he declined. He died April 17, 1628, leaving a widow and ten children.