In 1860, the Pennsylvania represented only the main line from Philadelphia to Pittsburgh, with a few short branches. By 1869 it had expanded within Pennsylvania alone to nearly one thousand miles and also controlled lines northward to the shores of Lake Erie, through New York State. In 1869 it purchased the Pittsburgh, Fort Wayne and Chicago line, giving it a connection with Chicago through Ohio and Indiana. In 1870 the Pennsylvania began to expand on the east coast also, obtaining an entry into New York City by acquiring the United Railroad and Canal Company, which owned leased 456 miles of railroad and 65 miles of canals in New Jersey. By 1873 Thomson also had links to the South. Thomson then built up Philadelphia as a transatlantic port, creating the American Steamship Company in 1870 under the control of the Pennsylvania Railroad. Steel was becoming available at moderate cost, and Thomson contracted with industrialist Andrew Carnegie for steel to replace all the wooden railway bridges, and to replace iron tracks with stronger steel tracks. With such infrastructure in place, trains could be designed to be heavier, faster, and more efficient.