LADD, William, philanthropist, born in Exeter, New Hampshire, 10 May, 1778; died in Portsmouth, New Hampshire, 9 April, 1841. He was graduated at Harvard in 1797, and on leaving college embarked as a sailor on one of his father's vessels, became a skilful navigator, and was captain of some of the finest ships that sailed from New England ports until he left the ocean at the beginning of the war of 1812. He resided at Minot, Maine, and took an active part in organizing the American peace society, of which he was for many years president. The society was founded in 1828, and for a long" period he was the only active and responsible officer. He gave his main attention to this society and the object it represented until the end of his life. In its interests he edited the "Friend of Peace," established by Dr. Noah Worcester, and the "Harbinger of Peace," which succeeded it as the organ of the society, and published a number of essays and occasional addresses on the subject of peace, including an "Address to the Peace Society of Maine" (1824), one to that of Massachusetts (1825), and "An Essay on the Congress of Nations " (Boston, 1840). He carried his views to the extent of denying the right of defensive war, and caused this principle to be incorporated into the constitution of his society. See his "Memoir," by John Hemmenway (Boston, 1872).