JACKSON, Thomas, a Scottish mathematician, was born at Waterhead of Deugh in the parish of Carsphairn and county of Dumfries on the 27th of December, 1773, and died at St. Andrews on the 17th of February, 1837. He was the son of a farmer. He received his education at the parish school of Tynren in Dumfriesshire and at the university of Glasgow, where he acted for some time as assistant to the professor of natural philosophy, and for two years performed the duties of the chair, while the professor was disabled from lecturing. From 1799 to 1809 he was rector of the academy of Ayr, and by his manner of conducting that school he established for it a high reputation. Besides the duty of general superintendence, he undertook that of instructing the elder scholars in physical science, then a rare feature in grammar-school education. In 1809 he was appointed to the chair of natural philosophy in the university of St. Andrews, which he held until his death. He contributed a few papers to scientific journals; but his constant devotion to his duties as a teacher prevented his engaging to any great extent in original research; and his only separate work was a text-book for his class entitled "Elements of Theoretical Mechanics," Edinburgh, 1827, one of the earliest elementary treatises by which a knowledge of the purely algebraic method of treating mechanical questions was communicated to British students.—W. J. M. R.
* JACKSON, Thomas, an eminent Wesleyan Methodist minister, was born at Sancton in Yorkshire, December 12, 1783. He entered on the work of an "itinerant Methodist preacher," as it was then termed, in the year 1804; came to London in that character in 1821; was appointed editor of the Wesleyan Methodist Magazine in 1824, and after sustaining that charge, and conducting through the press the works of Wesley, Fletcher, and Richard Watson, was constituted theological tutor in the Wesleyan theological institution in 1842, which office he still retains. He has been twice president of the conference; the first time during the centenary year of Methodism. He has written a life of John Goodwin the eminent puritan, of Richard Watson, Charles Wesley, and Robert Newton; a volume of expository discourses; another on the duties of christianity, &c., &c. The sale of some of these has been enormous.—J. T.
JACKSON, William, well known to all lovers of music under the familiar appellation of "Jackson of Exeter," was the son of a grocer, and born in that city in 1730. Having shown, while young, a strong propensity for music, he was, after receiving a liberal education, placed under the tuition of the organist of the cathedral of Exeter, with whom he continued about two years. He was then sent to study in London, and became a pupil of Travers, organist of the chapel royal, and imbibed no small portion of that composer's spirit; after which he returned to his native city, where he settled, and in 1777 was appointed to the places of sub-chanter, organist, lay-vicar, and master of the choristers of the cathedral. His talents for composition were first rendered conspicuous in the year 1755, by the publication of a collection of "Twelve Songs," which were so simple, elegant, and original, that they immediately became popular throughout the kingdom. These were followed by "Six Sonatas for the Harpsichord," in which his genius did not display itself with so much advantage as in his vocal compositions. His third work, consisting of "Six Elegies" in three parts, preceded by an invocation, affords such ample proofs of his taste, feeling, and judgment, as completely to establish his reputation, and rank him among the first vocal composers of his time. He afterwards published a second collection of "Twelve Songs," which delighted every ear, and justly added to the fame he had already obtained. His next publication was a book of "Twelve Hymns." In the preface to these are some useful hints concerning the style of this kind of composition; but the hymns themselves have no particular merit. He next printed a third collection of "Twelve Songs." His eighth work was an "Ode to Fancy," the words by Dr. Warton; and he shortly after gave to the public "Eight Sonatas for the Harpsichord," written, it is said, "with much taste and spirit;" but these have never fallen under our notice. His two sets of canzonets for two voices, in the whole twenty-four in number, enjoyed considerable popularity. "Time has not thinned my flowing hair," one of these, was sung at almost every public concert until within the last five-and-twenty years. Jackson was the composer of two dramatic poems, "Lycidas," altered from Milton's poem, and performed at Covent Garden in 1767 on the occasion of the death of the duke of York, brother to George III.; and "The Metamorphoses," a comic opera given without much success at Drury Lane in 1783. Of the latter he was supposed to be also the author. But, as a dramatic composer, his fame must rest on "The Lord of the Manor," produced at the last-mentioned theatre in 1781. The exquisitely tender and beautiful airs—"Encompassed in an angel's form," and, "When first this humble roof I knew"—are alone enough to preserve the piece from being forgotten. Besides the works enumerated, Jackson composed several church services well known in many cathedrals and parish churches. His service in F has been most unjustly censured, notwithstanding its great popularity. As a literary man, Jackson made himself known to the public in 1782 by the publication of two small volumes, entitled "Thirty Letters on Various Subjects" connected with literature and science. In 1791 he published a pamphlet "On the Present State of Music in London;" and in 1798 appeared his "Four Ages, together with Essays on Various Subjects." The greater part of the essays were sketches for an intended periodical paper, and show, as well as his letters, the extent of his reading, the variety of his knowledge, his taste, judgment, and independence of mind, whatever might be the subject on which he employed his pen. For many years, during the latter part of his life, Jackson laboured under the affliction of a severe asthma. He ultimately fell a victim to dropsy at the age of seventy-three in the month of July, 1803, leaving a widow, two sons, and a daughter, to lament his loss.—E. F. R.
JACKSON, William, was born in Dublin in the year 1737. At an early age he was sent to the university of Oxford, where he distinguished himself as a scholar, both scientific and classical. He took holy orders and attached himself to the earl of Bristol, who made him his private chaplain. When the earl was appointed to the viceroyalty of Ireland, Jackson was sent to that kingdom as his private secretary, but the resignation of his patron suddenly closed the bright prospects that were opening on him. Thrown on his own resources, Jackson went to London and took to political writing. His pamphlets against the ministry were of sufficient merit to attract the favourable notice of Chatham. He next became acquainted with the duchess of Kingston, who made him her confidential secretary; and when she was assailed by Foote, he wrote for her those remarkable letters which were published in the journals. At the period of the French revolution he went to Paris, and there entered into intrigues with the directory for the purpose of inducing them to invade Ireland. He returned to London in 1794 in order to obtain information as to the practicability of invading England, and was thence to proceed to Ireland on a similar mission. Here he renewed his intimacy with an attorney named Cockayne, whom he took into his confidence. Cockayne revealed all he knew or suspected to Pitt, by whose desire he accompanied Jackson to Ireland; and when the evidence of Jackson's guilt was complete, Cockayne tendered himself as evidence against him. In 1795 he was tried for high treason and found guilty. When brought up to receive sentence of death on the 30th of April he was evidently dying; and while his counsel were arguing a point of law in his favour, he sank in the dock and expired. The body was opened, an inquest held, and a verdict returned of death from poison.—J. F. W.
JACOB, surnamed Baradæus, otherwise called Jacobus Zanzalus, a monk or bishop, from whom the monophysites were called Jacobites, was a disciple of Severus in the sixth century. He commenced his labours at a time when monophysitism was at a very low ebb, in 505. He was ordained as a priest or bishop, it is uncertain which, and laboured with zeal as a missionary in Syria and Mesopotamia, where he gathered congregations, ordained ministers, and organized a regular ecclesiastical system. Jacob was much opposed by the orthodox, who brought various charges against him, which they disseminated by means of circular letters. He was too much under the influence of crafty and designing men. Nevertheless, the authority of Jacob was very great. He received back into communion Paul the Black, patriarch of Antioch, with whom he had quarrelled, and opposed the election of Peter, patriarch of Alexandria, with whom he was afterwards reconciled, although the reconciliation involved the deposition of Paul. Jacob found himself unequal to the task of checking the disorder which ensued, and which spread from Syria into Cilicia, Isauria, Asia, Cappadocia, and Armenia. Mondir, an Arab christian king,
