Remains of Conglog slate mill, Cwmorthin

Remains of Conglog slate mill, Cwmorthin

The path leading up to Rhosydd gives you a grandstand view across the compact site where slate from Conglog quarry was once processed.

The slate came from underground (north of the path) and was lowered on an incline to the long mill building. Mill machinery was powered by a waterwheel, nine metres (30ft) in diameter and 1.2 metres (4ft) wide. You can see the wheel pit at the end of the building. The stone piers leading towards the wheel pit carried water on an aqueduct. Beyond the mill is the waste rock left over after slate was sawn, planed and split.

Finished slate was taken from the site to a headshunt (near today’s gate across the path). There the wagons reversed to go down the valley, passing the quarrymen’s chapel.

When the Conglog Slate and Slab Quarry was auctioned in 1881 it included eight saw tables, a mechanical plane, two cranes, a weighing machine and 17 tram wagons.

Near the gate you can see the ruined quarry barracks called Rhosydd Terrace. The six cottages were built for families c.1865. Some of the workers at Rhosydd quarry lived there, enjoying slightly more shelter from the westerly wind than their colleagues in the main barracks higher up. . In 1881 one of these little cottages was occupied by a couple and their nine children – plus two lodgers! The last family here, headed by Robert O Williams, used one cottage as a wash house and another as a hen house. They moved to Plas Cwmorthin in the early 1940s.

Conglog quarry was worked from 1854 to 1909 but never employed many men. In 1890 it produced just 72 tons of slate (Rhosydd produced 4,876 tons). In the end, Conglog was a sideline for a couple of Rhosydd quarrymen in their spare time!

In 1907 Edward Rowlands, 64, of Tanygrisiau died at Conglog quarry after a five-ton rock fell onto him. He was part-owner of the quarry. As he bled to death, he was conscious for long enough to explain to colleagues how to move the boulder.

In 1902 John Jones of Tai Rhosydd had a lucky escape after the chain on which he was suspended broke, just after he had lit a fuse. Colleagues rushed down to move him to safety before the blast. He suffered severe facial wounds in the fall.

With thanks to Mel Thomas. Sources include ‘Gazeteer of Slate Quarrying in Wales’ by Alun John Richards, Llygad Gwalch 2007

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