How it began
In 1803 Samuel Homfray brought the Cornish engineer Richard Trevithick to his Penydarren ironworks at Merthyr Tydfil in South Wales. Homfray encouraged him to convert one of his high-pressure engines into a rail-mounted locomotive for the newly laid tramroad from Penydarren to the canal wharf at Abercynon. Trevithick appears to have started work in the autumn of 1803 and finished by February 1804. The first run took place on 21 February 1804 over about 9 miles.
Before it existed
In 1800 the fastest a person could travel over land was at a gallop on horseback. Iron from works such as Penydarren moved along tramroads to the canal. Trevithick had already developed high-pressure steam engines and installed them in road engines, and the Penydarren locomotive adapted that kind of engine to run on rails.
Who pushed back
Tradition holds that Richard Crawshay, owner of the nearby Cyfarthfa ironworks, was highly skeptical. He and Homfray are said to have wagered 500 guineas each on whether the engine could haul ten tons of iron to Abercynon and bring the empty wagons back. On the return journey a bolt sheared and the boiler leaked, so the engine did not get back until the next day. The engine also proved too heavy for the rails and later served as a stationary engine driving a forge hammer.
What changed first
Trevithick reported that the engine carried ten tons of iron in five wagons, with seventy men riding on them, at nearly five miles an hour, and that it burned two hundredweight of coal. It was the first recorded steam locomotive journey on a railway. It was still several years before steam locomotion became commercially viable.
What lasted
A century after the Penydarren run, much of the world had an extensive railway system on which trains regularly traveled at up to sixty miles per hour. Museum Wales describes that transformation as having been initiated in South Wales in February 1804. A replica built from Trevithick's original plans was inaugurated in 1981 and is displayed at the National Waterfront Museum.
