Merthyr Tydfil to Aber Cynon Tramroad – part 1

by Gwilym and John Griffiths

Some sources have recorded that this tramroad (then called a dram road) was started around 1800 by agreement between William Taitt of Dowlais, Samuel Homfray of Pen y Darren and Richard Hill of Plymouth. They added that the construction, under the supervision of George Overton, was allegedly started in 1799 and finished in 1802. Yet see under Leases 1800 for a few of the early leases in summary. It seems that Richard Fothergill was much involved in setting up these leases. In addition, the route was always described as being from Morlais Castle to Navigation House.  The route was from Pen y Darren to Aber Cynon, 9½ miles, a fall of 341 feet. Brief details were recorded in The Pen y Darren Locomotive by Stuart Owen-Jones.

The tramroad was used briefly (three times or numerous times, see below) with a trial of Trevithick’s steam engine on Tuesday 21 Feb 1804, returning to Pen y Darren the following day, but shortly thereafter the tramroad reverted to horse power for many further years. The weight of the steam-engine apparently damaged the rails. However, Charles Wilkins, ‘The History of Merthyr Tydfil’, page 252, thought that the engine, ‘after serving a long time on the tramway, was removed to a pit called Winch Fawr (in the hamlet of Heol Wermwd not the one in the hamlet of Gelli Deg), and finally taken to the top of the incline owned by the Pen y Darren Company at Cwm Bargod.’ We are not so sure. Richard Trevithick himself recorded the event from which the following summary is appropriate:

  1. On Saturday 11 Feb 1804, the fire was lit in the ‘Tram Waggon’ and Richard Trevithick worked it without the wheels to try the engine.
  2. On Monday 13 Feb 1804, they put the waggon on the ‘Tram Road’. It worked very well and ran up hill and down with great ease and was very manageable. There was plenty of power.
  3. Between 13 Feb and 20 Feb 1804 the ‘Tram Waggon’ had been worked several times. They had tried loads of up to ten tons, and it worked easily. He was sure it could cope with forty tons. Richard Trevithick intended making a smaller engine for the tram road as the first one had too much power, and would be used instead to work a hammer.
  4. On Tuesday 21 Feb 1804 they made the journey with the engine. They carried ten tons, presumably of iron, in five waggons, with seventy men riding on them for the whole of the journey. He recorded, very clearly, that it took four hours and five minutes to cover the nine miles because they had to cut down some trees and remove some large rocks out of the tram road. No mention of the stack being knocked down by a bridge or any problem with the ‘tunnel’ by Plymouth Works. They returned, but a broken bolt released the water, and the engine did not arrive back at Pen y Darren Works until the evening of Wednesday 22 Feb 1804. No mention of broken tramway plates or of having to be hauled back to Pen y Darren by horse.
  5. Later they tried the carriage with twenty-five tons of iron, and found the engine was more than a match for that weight. The steam was delivered into the chimney above the damper. It made the draught much stronger by going up the chimney. Trevithick’s locomotive was the first to employ this very important principle of turning the exhaust steam up the chimney, so producing a draft which drew the hot gases from the fire more powerfully through the boiler.

In May 1854, some forty years later, Thomas Ellis, an engineer from Tredegar, wrote a letter describing the first journey the Pen y Darren locomotive took in February, 1804. His father was at Pen y Darren when the engine was made and tried. Samuel Homfray, proprietor of the Pen y Darren Works, Merthyr Tydfil, made a bet of 1,000 guineas with Richard Crawshay, of the Cyfarthfa Works, that Trevithick’s steam-engine could convey a load of iron from his works to the Navigation House, nine miles distant.

To be continued……