Merthyr’s Bridges: Pont-y-Cafnau

The Grade II* listed Pont-y-Cafnau over the River Taff in Cyfarthfa is thought to be the world’s oldest iron tramroad bridge. An influential early prototype and is a unique survivor of its kind, it is also an aqueduct, with a water trough below the deck. Its designer was Watkin George (c.1759-1822), the chief engineer of the nearby Cyfarthfa Ironworks, which it served, and the bridge/aqueduct enabled the movement of limestone on its tram rails and a water supply, both for the ironworks. The limestone came from the Gurnos Quarries, and the water from a leat supplied by the Taf Fechan. The water was used to drive waterwheels to generate power to run machinery for iron smelting.

The structure was designed sometime in 1792 and construction began in January 1793 and the bridge was completed some time before 1796.

The distinctive appearance of the bridge is created by two large cast iron A-frames, which span the river, their raking ends embedded in the coursed rubble abutment walls on either side. The span measures 14.3m. Three transverse iron beams, at the halfway and quarter-points, connect the A-frames and support the deck. George was originally a carpenter and he used carpentry techniques for the ironwork – mortise-and-tenon and dovetail joints can be seen.

The deck consists of rectangular aqueduct trough, 1.9m wide and 610mm high, made of long iron plates. The trough is covered by an iron deck, cast in sections, on which was laid the 1.22m (4ft) gauge tramroad. Wagons ran on straight iron rails carried on iron chairs. Some chairs and sleepers are still in place along the full length and segments of rail survive at the southern end.

The cast iron handrails were supported at the centre and quarter points of the span. Most of the original cast iron railings have now been replaced.

In 1795, a second bridge was cast from the same patterns to carry an extension of the tramroad and aqueduct from the ironworks to the Glamorganshire Canal. This bridge, sadly, no longer exists.

Shortly after Pont-y-Cafnau was completed, the Gwynne Water Aqueduct (completed 1796) was constructed over the top of it. Gwynne Water was 185m long, built entirely of timber and used the cast iron uprights of the bridge for support. it supplied water to the 15m diameter Aeolus waterwheel, also designed by George, which powered an air pump for the blast furnaces. Presumably, the extra bracing that has been added to the bridge dates from this work. Nothing of the second aqueduct remains.

Pont-y-Cafnau is a Scheduled Ancient Monument as well as a Grade II* listed structure. The iron trough no longer carries water. However, its name means “bridge of troughs”, testifying to its former life.

The bridge influenced the construction of other, better known, aqueducts. In 1794, Shropshire ironmaster William Reynolds (1758-1803) made a sketch of it. Reynolds’ involvement in the rebuilding of Thomas Telford’s (1757-1834) navigable Longdon on Tern Aqueduct on the Shrewsbury Canal in 1796 seems to have led Telford to reconsider using stone and to opt instead for cast iron. It was also the prototype for Telford’s famous Pontcysyllte Aqueduct, which opened in 1805.

Pont-y-Cafnau in March 2017

Merthyr Memories: Twynyrodyn School

In the first of what I hope will be a new regular series of articles, I share my memories of Twynyrodyn School.

Whenever I drive along Primrose Hill in Twynyrodyn, and pass the site of the old Twynyrodyn School, I always feel a pang of regret. Regret that the old school is gone, and regret that I didn’t really appreciate it more when I was there. I attended ‘Twyn’ School for four years in the late 1970’s, and now, in retrospect I realise what an impact it made on my life.

Twynyrodyn School in the 1970’s. Photo courtesy of Philip Howard

Twynyrodyn Junior School was an old school (I have since found out it was built in 1875), and was originally two schools – a boy’s school and a girl’s school, and these two ‘wings’ were separated by the central hall (in days gone by this was apparently the ‘infants’ school). The corridors were tall and echoing and tiled throughout, and in the old boy’s school wing were a flight of stone steps, leading to three upper classrooms, that had been worn down over the course of decades by the feet of thousands of children and staff going to and from their classes.

The classrooms were large and airy, lit by tall gothic windows. In my classroom (in the old boy’s wing, and incidentally the same classroom where my grandfather was pupil in the 1910’s on ’20’s) we had old individual desks with lifting lids and (now redundant) inkwells, all arranged in straight lines facing the door, with the blackboard to one side on an easel. Along the one wall were two very large, old cupboards containing text-books, some of which I am convinced hadn’t been looked at for decades. The walls of the classroom were lined with educational posters, and I remember vividly that the poster next to my desk depicted British Castles, and I spent many hours staring at that poster and dreaming of visiting all of the castles shown….I am getting there slowly!!!!!

In my day, the staff consisted of nine teachers and the headmaster, Mr Ken Adams-Morgan – red-faced, eyebrows with a personality all of their own, and feared by all!!!! I have since realised of course, that he was a very good and a very fair headmaster, not to mention a fine musician, and the school ran like clockwork under his leadership. The teachers were: Miss Davies, Mrs Phillips, Mrs Evans, Mrs Thomas and Mr Fitzgerald over in the old girl’s school (or over the other side as we used to say); and on ‘our side’: Mr Price, another Mrs Phillips, Mr Morgan, and last but by no means least, my own teacher – Mr Humphries.

I was taught by Mr Eddie Humphries for the whole time I was at Twyn School. Mr Humphries was a big man – in every sense of the word. He was a teacher of the ‘old school’, a strict disciplinarian, and focusing very much on ‘the Three R’s’. English and Maths were drilled in to us on a daily basis, with spot tests on spelling and times-tables. I didn’t mind the spelling tests – I was usually very good with those, but the times-tables struck fear into my heart. Anything mathematical still brings me out in a cold sweat. Mr Humphries had a cane hanging behind his desk, and in the four years I was in his class, I never recall him using it – the fact that it was there was enough!!!!

The above makes it sound as if Mr Humphries was a fearsome tyrant. He wasn’t. Every one of us respected him, and I know everyone I speak to today who had the privilege of being taught by him, still remembers him fondly. I know that Eddie Humphries had a profound effect on my life. Without doubt he was the biggest influence in my life, and made me the person I am today – for that I will always be grateful. If I can try to live by the standards he instilled in us all, and if I can be half the man he was, I will count myself a very lucky person.

I’m sure children today would think that the above description of school is from a totally bygone age, but it is in fact just 40 years ago. Schools and the process of teaching have totally changed – but are these changes for the better?

Twynyrodyn School is gone now. It closed in 2003 and amalgamated with the infants school, and the building was demolished in 2008, but it still holds a very special place in my memories.

Twynyrodyn School in 2003. Photo courtesy of http://www.alangeorge.co.uk/index.htm

If anyone has any Merthyr related memories that they would like to share, please get in touch. They can be about any subject as long they are connected with Merthyr.