Middle Duffryn Colliery

Overview

One of the earliest collieries to work the Aberdare steam coal, sunk in the 1840s by Thomas Powell beside the canal midway between Aberdare and Mountain Ash. Two shafts of 167 yards, one later deepened to 293 to reach the Gellideg, worked a seam so gassy that the pit was the scene of three separate disasters: at least eight dead in December 1850, sixty-four on 10 May 1852 — the worst in the Cynon valley to that date — and three killed in a shaft accident in 1858. Powell Duffryn took it over in 1864; production ceased in the late 1880s and the pit was kept on for pumping and ventilation.

History

Thomas Powell, a timber merchant from Newport who became the largest coal exporter in the world, sank Middle Duffryn in the 1840s — the People's Collection Wales compilation gives 1843 — on the right-hand side of the Aberdare valley at the foot of Duffryn mountain, beside the canal and about two miles from both Aberdare and the Mountain Ash station of the Taff Vale Railway. It lay between the older Duffryn or Cwmpennar pit at Cwmbach and the Lower Duffryn at Mountain Ash, and was among the first collieries in the district to work the steam coal seams that made the valley's name. The men who worked it lived largely in the cottages beside Lletty Shenkin, across the valley.

It was a gassy pit and its record is dominated by three disasters. On 12 December 1850 a roof fall released gas which was fired at a candle, killing at least eight (see Disasters, below). Eighteen months after that, on Monday 10 May 1852, came the explosion that killed sixty-four of the ninety-two underground (see Disasters, below). In July 1858 three men died when the bucket carrying seven down the shaft fell to the bottom (see Disasters, below).

The colliery came under the ownership of the Powell Duffryn Steam Coal Company in 1864. Production ceased in the late 1880s, and the Inspector of Mines list for 1896 records it as kept for pumping and ventilation only; a photograph of about 1900 shows it in that role.

Geology

The colliery worked the steam-coal measures of the South Wales Coalfield on the eastern side of the Cynon valley, and was one of the first in the district to do so. The two shafts were sunk to 167 yards and No. 1 was later deepened to the Gellideg seam at 293 yards, taking the workings through the sequence below the four-feet. The seam worked here was the same highly gaseous coal worked at Lletty Shenkin across the valley, a fact the newspapers pointed out when comparing the two collieries' explosions, and gas dislodged from the roof by falls — what the reports of 1852 called a blower — is the recurring cause in the colliery's accident record.

Geological setting: Sedimentary Beds and Seams (well documented example)

Workings

Two shafts, Nos. 1 and 2, each 167 yards deep, No. 1 later deepened to 293 yards to reach the Gellideg. The ventilation shaft was divided down its whole depth by brattice cloth on a timber frame, so that one shaft served as both upcast and downcast. Ventilation in 1852 was by a furnace at the bottom of the winding shaft together with a steam jet at the top of the upcast, running night and day and driving twenty-eight to thirty thousand cubic feet of air a minute through the workings — strong enough, one collier said, that he had to shelter his candle in a lantern to keep it alight. Firemen examined every working place and the main returns each morning before issuing lamps, and no one was to go in-bye of the lamp room until they had reported the workings safe; naked candles were nonetheless permitted, and normal, wherever no firedamp appeared. Horses worked underground. After production ended the pit was kept on for pumping and ventilation.

Closure

Production ceased in the late 1880s. The Inspector of Mines list for 1896 records the colliery as kept for pumping and ventilation only, and it was still serving that purpose when photographed about 1900.

What remains

Nothing is recorded of what survives on the site. The colliery stood beside the line of the former Aberdare Canal between Aberdare and Mountain Ash, ground since much altered by twentieth-century industry and road building.

Redevelopment

None recorded.

Related mines

• Lletty Shenkin Colliery — The two pits worked the same highly gaseous seam across the Cynon valley from each other, a comparison the newspapers drew directly after the 1852 explosion; the Middle Duffryn men lived largely in the cottages beside Lletty Shenkin, and the father of the two Marks boys killed in 1852 had himself been killed by an explosion at Lletty Shenkin that December.
• Lower Duffryn Colliery — Neighbouring Thomas Powell pits in the Aberdare valley; their names overlap in the sources.
• Old Duffryn Colliery — Both Thomas Powell's Duffryn pits at Aberdare, later worked by the Powell Duffryn Steam Coal Company.

Disasters & major incidents

• Middle Duffryn Colliery explosion, 1850
  12 December 1850 · Explosion · 8 fatalities
  Between three and four in the afternoon of 12 December 1850 a fall of roof in No. 4 heading of Middle Duffryn Colliery released gas that fired at the candle of the fireman, Henry Jenkins, who was cutting a new wind-way to keep the air course open. The blast killed men underground and a sawyer at the pit top, and more died of their burns over the following week. The number of dead is given as eight or thirteen.
• Middle Duffryn Colliery Explosion, 1852
  10 May 1852 · Explosion · 64 fatalities
  Ninety-two men and boys went down Middle Duffryn Colliery on the morning of Monday 10 May 1852. Shortly before nine o'clock a fall in the deep heading released gas which exploded; sixty-four died and twenty-eight came out alive. Fifty-five were killed in the explosion and its afterdamp, and nine more died escaping when the platform they had gathered on in the shaft gave way. It was the worst disaster in the Cynon valley to that date.
• Middle Duffryn Colliery shaft accident, 1858
  10 July 1858 · Winding / Shaft Accident · 3 fatalities
  Seven men descending Middle Duffryn's shaft in the bucket in July 1858 fell to the bottom when the bucket caught the guide chain and the hauling chain broke; three were killed and four badly hurt.

What's uncertain

Points where sources disagree or the record could not be settled; both accounts are kept. All open questions in the archive.

• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Middle Duffryn' (catalogue SFE44, Surface, undated in the catalogue); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain) ³

Recorded claims

Individual factual claims, each attached to the source(s) that support it below. Where sources disagree, both are kept.

• Middle Duffryn was sunk in the 1840s by Thomas Powell, a timber merchant from Newport, beside the canal midway between Aberdare and Mountain Ash; the People's Collection Wales compilation gives 1843. ^1,2
• There were two shafts, Nos. 1 and 2, each 167 yards deep, No. 1 later deepened to the Gellideg seam at 293 yards; the ventilation shaft was divided down its depth by brattice cloth on a timber frame so as to serve as both upcast and downcast. ²
• Ventilation was by a furnace at the bottom of the winding shaft together with a steam jet at the top of the upcast, driving twenty-eight to thirty thousand cubic feet of air a minute through the workings. ¹
• The colliery passed to the Powell Duffryn Steam Coal Company in 1864, ceased production in the late 1880s and was kept for pumping and ventilation only, as the Inspector of Mines list for 1896 records. ²
• The BGS mine-plans catalogue holds a Mining Remediation Authority abandonment plan titled 'Middle Duffryn' (catalogue SFE44, Surface, undated in the catalogue); the catalogue gives no location and the plan's details do not clearly tie it to this working, so it may belong to another of the same name. (uncertain) ³

Photographs & further reading

Sources

1. (secondary) The Aberdare Valley Colliery Disasters 1845-1861 — People's Collection Wales
2. (secondary) Middle Duffryn Colliery, Aberdare — Welsh Coal Mines
3. (primary) BGS / Mining Remediation Authority mine plans: MIDDLE DUFFRYN — British Geological Survey / Mining Remediation Authority
4. (secondary) Death Rolls: Middle Duffryn Colliery, 12 December 1850 and 10 May 1852 — Welsh Coal Mines

Record created: 3 September 2026 · Last researched: 4 September 2026