WILLIAMS, Jonathan, soldier, born in Boston, Massachusetts, 26 May, 1750; died in Philadelphia, Pennsylvania, 16 May, 1815. His father, of the same name, was a patriot of the Revolution. The son received a good education, entered a counting-house in Boston, and then made several voyages to the West Indies and to England. He was in the latter country in 1770 and 1773, and was intrusted by his grand-uncle, Benjamin Franklin, with political despatches to this country. He was also Franklin's secretary during the latter's residence in France as United States ambassador, and for part of the time served as United States commercial agent. While in France he studied military science, especially fortification. After his return to this country in 1785 he was for several years a judge of the court of common pleas in Philadelphia, but on 6 February, 1801, he was appointed major of the 2d regiment of artillerists and engineers in the regular army, and on 4 December he was made inspector of fortifications, and took command of the post at West Point, with the duties of instruction in his branches. On the establishment of the present military academy in 1802 he became its superintendent, but on 20 June, 1803, he resigned his commission on a question of rank. On 19 April, 1805, he returned to the army, at President Jefferson's request, as lieutenant-colonel and chief engineer, resuming also the superintendence of the academy. He planned and built most of the inner forts in New York harbor, including Fort Columbus, Fort Clinton (now Castle Garden), and Castle Williams, which was named for him. At the beginning of the war of 1812 Colonel Williams claimed the command of the last-named work, and on being refused it by the secretary of war, resigned, 31 July, 1812. He then returned to Philadelphia, and was for several years vice-president and corresponding secretary of the American philosophical society, he was elected to congress in 1814, but died without taking his seat. Colonel Williams has been called "father of the corps of engineers?' His full-length portrait is in the library of the United States military academy, among those of other superintendents and professors. He was the author of a memoir on "The Use of the Thermometer in Navigation" (Philadelphia, 1799), and translated " Elements of Fortification" (1801) and Kosciusko's " Manoeuvres for Horse Artillery" (1808), besides contributing to the "Transactions" of the American philosophical society.--His son, Alexander John, soldier, born in Philadelphia in 1790; died in Fort Erie, Upper Canada, 15 August, 1814, was graduated at the United States military academy in 1811, and assigned to the engineers, but was made captain of artillery, 17 March, 1813. He commanded Fort Mifflin, Pennsylvania, in 1812-'14, and then engaged in the campaign on the Niagara frontier. During the defence of Fort Erie, while he was repelling the fourth assault of the enemy in a hand-to-hand encounter, a lighted port-fire in front of the British enabled them to direct their volleys on his company, He sprang forward, cut it off with his sword, and fell mortally wounded by a musket-ball.