The area around Machynlleth fairly bristles with slate quarries- the mighty Corris enterprises like Braich Goch spring to mind, or Ratgoed and Aberleffeni. The name Morben was a new one for me and although it isn't on the same scale as those great quarries near Corris, it certainly has much in the way of charm and fascination. It's lost in thick woodland above Derwenlas, a couple of miles west of the town.
We made things a little difficult for ourselves by trying to reach the quarry from above, using a little road that goes over the shoulder of Mynydd Cynffrych. It's a lovely road and passes some interesting cottages where, at one point, we found some feral Citroen 2CV's, sans engines and much else besides. Presumably another Citroen, sporting the cannibalised bits, was chuntering about the lanes somewhere. There was a new footpath here, recently laid out and entreating the walker to "Discover Dyfi". Curious, we ventured along it. After walking for five minutes, we realised it wasn't going anywhere interesting. A mighty wooden bridge with gates at either end had been built across a minute stream- obviously the sort of path made for walkers who don't like to get their new boots dirty, or go anywhere too far off the beaten track.
It didn't seem possible to gain access from the top, so we returned to where we had parked the truck and headed back down to the pell-mell of the A487. As we passed the woods, Petra spotted what she thought was an incline, so we parked in a gravel area and walked back. At last, the game was afoot and we tramped up into the beech woods to find the first structure mentioned by Richards in the Slate Gazetteer (1). This is a two-roomed powder house. It still has the remains of the wood lining to the walls, although the roof has been robbed of slate in the last few years. It is deteriorating rapidly and is pretty much the only remaining structure on site, apart from the vestigial remains of the drum house at the top of the incline. Where the office, also mentioned in the Gazetteer, was hiding...that was to remain a mystery.
Feeling very enthusiastic, we carried on uphill, where an adit came into sight. It is flooded almost up to roof height and appears to be blocked partway along. To my mind it seems obvious that this was for access to the pit and for drainage, as there was a fair quantity of water issuing from the mouth, where a berm of earth has been pushed up to discourage access. Further up the hill, through thick Birch, Bramble and Beech saplings, the pit can be seen through a narrow opencut. The strata of the rock is very interesting - I found this, from the "Geology Wales" site which gives an idea of the significance:
"This disused slate quarry is of regional geodiversity importance because it provides a
particularly well-exposed section from the Cwmsymlog Formation into the Devil’s Bridge
Formation. These Lower Silurian formations comprise mudrocks that clearly illustrate the
effects on sedimentation of variations in the oxygen content of the sea-bottom in deeper parts
of the Welsh Basin. The rocks are deformed by an unusually tight fold, seen in 3-dimensions,
in which part of the succession has been inverted. The style of quarrying is noteworthy: a
deep vertical-sided pit that required a tunnel (adit) to drain it and remove the slates."
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The faint line of the tramway goes from the bottom left corner to the incline crimp to the right of centre. |
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The Drum House remains |
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Inside the pit from the lower opencut |
The National Library of Wales records contain a document by J H Evans (3) which sheds a tiny chink of light on the mysteries of the site:
"One of the last two boats to sail to Derwenlas brought a load of powder to be stored in a magazine-which is still there, up in the woods by Morben Quarry -and taken out when wanted by the quarries at Corris and Aberllefeni. The boat lay by the side of a meadow close by and the powder, in small casks, was taken to the magazine. The day was a jubilee for the hauliers, as they got good pay for the haulage. The secretary of the powder company was Mr. John Evans, father of Mr. W. P. Evans, J.P., and Mr. Albert Evans."
As is often the case, a visit to a quarry, one that we thought would be a straightforward and fairly uninteresting site, has proved to be a fascinating study. Derwenlas, too, is obviously worthy of further scrutiny.As for the rest of the known facts about the site, Morben was predominantly a slab quarry. It's produce mainly went to the enamelling works at Aberystwyth via the Cambrian Railways.
And for all this talk about explosives...close examination of the quarry faces has shown no marks of shot holes, indeed the rock looks to have been crowbarred off the face.
(1) Gazetteer of Slate Quarrying in Wales, Alun John Richards, ISBN: 1-84524-074-X
(2) BT 31/3954/25083 25083 Morben Slate and Slab Quarry Company Ltd 1887 (Wales National Archives)
(3)"Derwenlas" Montgomeryshire Collections, Vol. 51, (1949-1950), p. 75-85.
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The powder house gable wall |