Penidarren locomotive 1804 -

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Penidarren locomotive 1804

History locomotives

Penidarren locomotive 1804

The very first steam-powered railway locomotive in the world. Designed and built  by the Cornish engineer Richard Trevithick, this remarkable contraption was put to work on the Pen-y-Darren tramway in South Wales in 1804 - no less than 21 years before the opening of the Stockton & Darlington Railway.

Penidarren locomotive 1804

Penidarren locomotive 1804

Introduced  1804
Designer  Trevithick

Driving wheel dia  3ft 9in

Cylinder (1)  8in  x  4ft  6in

Weight  5  tons

Status  Scrapped

The locomotive bore no name or number, but is referred to simply as the Pen-y-Darren engine (or Penydarren for short). Some historians are of the opinion that Trevithick may have overseen the building of another railway engine at Coalbrookdale, in Shropshire, two years earlier, but there is no evidence whatsoever that it was ever completed, let alone operated, which is why the bicentenary of steam railways was celebrated in 2004 and not 2002.

Even details concerning die Penydarren engine
are sketchy; no contemporary illustration exists and only a few dimensions have been passed down through the ages. From those, it has been possible to build a working reconstruction, which is today under the wing of the National Museum for Wales. It takes the form of a four-wheeled machine driven by a large cogwheel, which in turn is powered by a huge flywheel.

The boiler had just one flue, traversing the barrel once in either direction and there was only one cylinder, which made the flywheel necessary to keep the loco in motion at the end of each very long cylinder stroke. This principle may seem outdated, yet remained in use on many traction engines and road rollers until well into the 20th century.

After its debut on February 21, 1804,
Penydarren continued hauling trains but proved too heavy for the primitive cast iron plateway, whose rails cracked in several places. Eventually, the tramways owner decided to revert to horse power, meaning that steam locomotion might have been a short-lived one-off experiment - but Trevithick had other plans and in 1808 produced a passenger-hauling engine named Catch Me Who Can, which ran on a circular track in London and brought the potential of steam power to a much wider and more influential audience. The genie was out of the bottle!
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