Stephenson's 'Planet' locomotive, 1830. Plan (scale 1:8) of Planet showing tender, rear elevation of tender, general side elevation of engine and tender. The Planet design was built by Robert Stephenson & Co for the Liverpool and Manchester Railway. It marked a great advance on 'Rocket', the Rainhill Trials winner of 1829, in having its two cylinders placed at the front end between the frames under the smokebox, and in having an enclosed firebox. These and other improvements gave it a great increase in power over Rocket-type locomotives. The design of Planet formed the basis on which much of the later development of the steam locomotive was founded.
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