Mellon, Andrew William, 1855-1937, American financier, industrialist, and public official, b. Pittsburgh. He studied at the Western Univ. of Pennsylvania (now the Univ. of Pittsburgh), but he left college to organize a lumber business with his brother, Richard B. Mellon. Soon they joined interests with their father, Thomas Mellon, a successful Pittsburgh banker and lawyer, who had helped Henry C. Frick to expand his holdings in the coke industry. When Thomas Mellon retired (1886), the sons took over the banking firm of Thomas Mellon and Sons. In 1889, Andrew Mellon led in establishing the Union Trust Company of Pittsburgh—later to become one of the larger financial institutions in the United States and merge with the Mellon National Bank (and ultimately become Mellon Financial Corporation)—and the Union Savings Bank was created as a subsidiary firm. Meanwhile Andrew Mellon expanded his holdings in key American industries and secured large interests in the Gulf Oil Company, the American Locomotive Company, the Pittsburgh Coal Company, and in hydroelectric, bridge-building, public-utility, steel, insurance, and traction companies. He also played an important role in originating the huge Aluminum Company of America (Alcoa).

Mellon resigned (1921) as president of the Mellon National Bank to become U.S. secretary of the treasury and held that cabinet post until 1932 under Presidents Harding, Coolidge, and Hoover. As secretary, Mellon worked for a downward revision of income taxes and surtaxes, and in spite of drastic tax curtailments, he reduced the national debt from $24,298,000,000 in 1920 to $16,185,000,000 in 1930. He later served (1932-33) as U.S. ambassador to Great Britain. His income-tax return for the year of 1931 was the subject of a federal investigation in 1935, but he was exonerated in Dec., 1937, four months after he died. He gave $10 million for the founding (1913) of the Mellon Institute of Industrial Research in Pittsburgh (since 1967 Carnegie Mellon Univ.); in 1937 he donated his art collection to the public, with funds for the erection of a building in Washington in which to house it (see National Gallery of Art). He wrote Taxation: The People's Business (1924).

(born March 24, 1855, Pittsburgh, Pa., U.S.—died Aug. 26, 1937, Southampton, N.Y.) U.S. financier. He joined his father's banking house in 1874 and through the next three decades built up a financial empire by supplying capital for corporations in industries such as aluminum, steel, and oil. He helped found the Aluminum Co. of America (Alcoa) and the Gulf Oil Corp., and he joined Henry Clay Frick to found Union Steel Co. and Union Trust Co. By the early 1920s he was one of the richest men in the U.S. As secretary of the Treasury (1921–32) he persuaded Congress to lower taxes in order to encourage business expansion. He was praised for the economic boom of the 1920s but criticized during the Great Depression, and in 1932 he resigned to serve as ambassador to England. A noted art collector and philanthropist, Mellon donated an extensive art collection and $15 million to establish the National Gallery of Art.

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