Mostyn Colliery explosion, 1840

An explosion at Mostyn Colliery, Flintshire, in the summer of 1840 blew large lumps of coal up a shaft 390 feet deep. Eight men were killed outright and a man and a boy were brought out badly burnt; eleven died in all and five more were seriously injured, leaving six widows and thirty fatherless children.

Cause

An explosion of firedamp (the pit 'fired').

Contributing factors

Unknown.

What happened

The explosion happened in a pit whose shaft was 390 feet deep, and its force carried large lumps of coal up to the surface. Eight men died in the workings. A man and a boy were brought out fearfully burnt, and the toll reached eleven, with five others seriously injured. Six women were widowed and thirty children left fatherless. A newspaper of the following week reported it as the loss of eight lives.

Rescue & recovery

Unknown.

Investigation & inquiry

Unknown.

Legal & regulatory aftermath

Unknown.

Changes to practice & legislation

Unknown.

Memorials & commemoration

A plaque in the Welsh National and Universal Mining Memorial Garden at Senghenydd commemorates it.

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 explosion took place in July 1840. (disputed) ^1,2,3
• The Durham Mining Museum's disaster page dates the explosion 4 August 1840, and lists a Monmouthshire Merlin report of 8 August 1840 headed 'Loss of Eight Lives at Mostyn Colliery'. (disputed) ⁴

Recorded claims

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

• The explosion took place in July 1840. (disputed) ^1,2,3
• The Durham Mining Museum's disaster page dates the explosion 4 August 1840, and lists a Monmouthshire Merlin report of 8 August 1840 headed 'Loss of Eight Lives at Mostyn Colliery'. (disputed) ⁴
• Eight were killed in the explosion; eleven lost their lives in all and five others were seriously injured, leaving six widows and thirty children fatherless. ^1,3
• Eleven died in the 1840 explosion at Mostyn. ^5,4,2
• The 1840 disaster is commemorated by a plaque at the Welsh National and Universal Mining Memorial Garden, Senghenydd. ²

Related terminology

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

• Coal (contextual relationship)
  Named twice in this record, first in the summary: “…Colliery, Flintshire, in the summer of 1840 blew large lumps of coal up a shaft 390 feet deep. Eight men were killed outright and a man…”
• Colliery (contextual relationship)
  Named in this record’s summary: “An explosion at Mostyn Colliery, Flintshire, in the summer of 1840 blew large lumps of coal up a…”
• Firedamp (direct cause)
  The pit 'fired'.
• Shaft (contextual relationship)
  Named twice in this record, first in the summary: “…Flintshire, in the summer of 1840 blew large lumps of coal up a shaft 390 feet deep. Eight men were killed outright and a man and a boy…”

Plans & documents

Sources

1. (secondary) Mostyn Colliery Explosion - Mostyn - 1840 — Northern Mine Research Society
2. (secondary) Memorial: 1840 Mostyn Colliery Disaster — Durham Mining Museum
3. (secondary) Mining disasters in Great Britain, 1840–1849 — Coal Mining History Resource Centre
4. (secondary) Colliery Disaster: Mostyn, 4th August 1840 — 11 lives lost — Durham Mining Museum
5. (secondary) The miners of Mostyn — Heritage Hunter

Record created: 20 September 2026 · Last researched: 21 September 2026