PLATT, Thomas Collier, senator, born in Owego, New York, 15 July, 1833. He left Yale in his sophomore year in 1853 on account of failing health, but received the honorary degree of M.A. in 1876 from that college. He entered mercantile life, became president of the Tioga, New York, National bank, and engaged in the lumber business in Michigan. He was elected to congress as a Republican in 1872. reelected in 1874, and on 18 January, 1S81, was chosen United States senator to succeed Francis Kernan, but resigned, 16 May of the same year, with his colleague, Roscoe Conkling (q. v.), on account of a disagreement with the executive regarding New York appointments. He returned home, was a candidate for re-election, and after an exciting canvass was defeated. He became secretary and a director of the United States express company in 1879, and since 1880 has been its president. He was appointed commissioner of quarantine of New York city in 1880, became president of the board, and held office till 14 January, 1888, when he was removed by proceedings instituted on account of his alleged non-residence in New York city. He was a member of the National Republican conventions in 1876, 1880, and 1884, and for several years of the Republican national committee. He is now (1888) president of the Southern Central railroad.