JACOBUS, Melanchthon Williams, clergyman, born in Newark, New Jersey, 19 September, 1816; died in Allegheny City, Pennsylvania, 28 October, 1S76. He was graduated at Princeton in 1834, and at the theological seminary there in 1838, after which he spent an additional year in study, at the same time assisting the professor of Hebrew. He was ordained minister of the 1st Presbyterian church of Brooklyn on 15 September, 1839. After a successful pastorate of nearly twelve years his health failed, and he made a tour through Europe, Egypt, and the Holy Land. On his return, in 1851, he accepted the professorship of oriental and biblical literature in the theological seminary at Alleghany City, where he remained till he died. From 1858 till 1870 he filled the pastorate of the Central Presbyterian church in Pittsburg in addition to his work in the seminary. In 1869 he was moderator of the last general assembly of the old school branch of his church, and in 1870 presided, conjointly, with Reverend Dr. Philemon H. Fowler, at the opening of the first assembly of the reunited church. He was an effective public speaker, and held a high place among biblical scholars. He received the degree of D. D. from Jefferson college in 1852, and that of LL. D. from Princeton in 1867. He published "Letters on the Public School Question" and "Notes on the New Testament" (4 vols., New York, 1848-'59). These commentaries, which were designed for Sunday school and family use, were popular among all denominations. He also published "Notes on Genesis" (2 vols., 1864-'5).