William Maclay (məklā´), 1734–1804, U.S. Senator from Pennsylvania (1789–91), b. Chester co., Pa. A lawyer and a provincial and state official before serving as Senator, he kept a journal, not published until 1880 (later ed. by Charles A. Beard, 1927), which gives the fullest, firsthand account of the debates in the Senate during the 1st Congress (1789–91). The journal reveals Maclay's opposition to Alexander Hamilton's policies and his defense of the interests of the small farmer.