Seth ThomasBorn 19 Aug 1785; died 29 Jan 1859 at age 73.American clock manufacturer who was one of the pioneers in the mass production of clocks. After working with Eli Terry and Silas Hoadley in firm of Terry, Thomas & Hoadley, which manufactured clocks by mass production methods (1807), Thomas founded a clock factory of his own at Plymouth Hollow, Conn. (1812). He was not an inventive genius, but he was an excellent mechanic and a keen business man. Two years later he paid Terry for the rights to manufacture the latter's popular shelf clock. Shortly, he was selling as many clocks as Terry. As his business developed Thomas built a mill for rolling brass and making wire at Plymouth Hollow, and operated it in conjunction with the clock factory. Finally, he organized the Seth Thomas Clock Co. (1853).