Machen Colliery explosion, 1858

On 26 April 1858 gas exploded at Augustus Morgan's colliery at Machen in the lower Rhymney valley; three men and a boy died of their burns, and the inquest heard that a safety lamp found at the scene had a faulty clasp.

Cause

An explosion of gas; one of the safety lamps found at the scene had a faulty clasp, which held its protective gauze in place.

What happened

Machen Colliery was a group of small pits and slants at Machen, begun in the 1840s by Augustus Morgan to supply the limekilns of his father's quarry. On 26 April 1858 gas exploded in the workings, burning several men. Three men and a boy died: some at once and at least two of the injured in the weeks that followed, while others were still suffering severely from their burns in mid-May. Two years later the owners went bankrupt and further development of the colliery stopped.

Investigation & inquiry

The Government Inspector of Mines, W. H. Brewer, formally opened an inquiry into the deaths of two of the men early in May, with Herbert Mackworth present. Because another death was expected and some witnesses were not yet fit to give evidence, it was adjourned to Friday 4 June. At the inquest one of the safety lamps recovered from the scene was shown to have a faulty clasp.

Recorded claims

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

• A gas explosion at Machen Colliery on 26 April 1858 killed three men and a boy. ¹
• Two of the men injured in the explosion died in the week before 8 May 1858. ²
• The Government Inspector, W. H. Brewer, opened an inquiry into two of the deaths and adjourned it to 4 June because witnesses were still too badly hurt to give evidence. ³
• At the inquest a safety lamp found at the scene was shown to have a faulty clasp on its gauze. ¹

Related terminology

Mining terms this disaster is structurally linked to, with the nature of the relationship.

• Colliery (contextual relationship)
  Named 3 times in this record, first in the summary: “On 26 April 1858 gas exploded at Augustus Morgan's colliery at Machen in the lower Rhymney valley; three men and a boy died of…”
• HM Chief Inspector of Mines (contextual relationship)
  Named in this record’s investigation: “The Government Inspector of Mines, W. H. Brewer, formally opened an inquiry into the deaths of two of…”
• Lime Kiln (contextual relationship)
  Named in this record’s narrative: “…at Machen, begun in the 1840s by Augustus Morgan to supply the limekilns of his father's quarry. On 26 April 1858 gas exploded in the…”
• Safety Lamp (contextual relationship)
  Named 3 times in this record, first in the summary: “…men and a boy died of their burns, and the inquest heard that a safety lamp found at the scene had a faulty clasp.”
• Slant (contextual relationship)
  Named in this record’s narrative: “Machen Colliery was a group of small pits and slants at Machen, begun in the 1840s by Augustus Morgan to supply the…”

Photographs & further reading

This page doesn't try to reproduce everything — these are the best original sources found for this disaster.

Sources

1. (secondary) Welsh Coal Mines: Machen (Old Machen (Pentwyn) Colliery) — Welsh Coal Mines
2. (primary) 'Machen', Monmouthshire Merlin, 8 May 1858 — Welsh Newspapers Online (National Library of Wales)
3. (primary) 'Machen. The late colliery explosion', Monmouthshire Merlin, 15 May 1858 — Welsh Newspapers Online (National Library of Wales)

Record created: 10 October 2026 · Last researched: 10 October 2026