Cwmdare Colliery gas accident, 1879

Three men were suffocated at Cwmdare Colliery, Aberdare, on the night of 18 October 1879 when gas burst from a choked drainage pipe they had opened; the overman with them escaped.

Cause

Gas released in volume from a choked water pipe between the Bute Vein heading and the Nine Feet when its tap was opened; it was described at the time as 'sulphurated hydrogen'.

What happened

By the autumn of 1879 Cwmdare Colliery was little worked. Water from the Nine Feet seam was drained through a pipe laid in a hard heading driven from the Bute Vein, and when the men noticed that no water was flowing the pipe was taken to be choked. About nine on the Saturday night the overman, John Lewis, went down with three men to clear it.

George Wood and James Kempthorne opened the large tap before running an iron rod along the pipe, and gas poured out. Lewis, standing by with the only light, a safety lamp, saw the place filling and called the men away; he got out himself in a daze. The three went the other way and were overcome within a few yards of the pipe. The dead were the blacksmith George Wood, 29, married with three children; James Kempthorne, an engineman; and David Deer, an engineman of eighteen.

Rescue & recovery

The bodies were recovered at about noon the next day.

Recorded claims

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

• Three men were suffocated by gas at Cwmdare Colliery on 18 October 1879. ^1,2
• The gas came from a choked drainage pipe between the Bute Vein heading and the Nine Feet when its tap was opened. ¹
• Four men went down to make repairs; the fourth, overman John Lewis, escaped. ^1,2
• The bodies were recovered about noon the next day. ¹

Related terminology

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

• Colliery (contextual relationship)
  Named twice in this record, first in the summary: “Three men were suffocated at Cwmdare Colliery, Aberdare, on the night of 18 October 1879 when gas burst from a…”
• Overman (contextual relationship)
  Named twice in this record, first in the summary: “…1879 when gas burst from a choked drainage pipe they had opened; the overman with them escaped.”
• Safety Lamp (contextual relationship)
  Named in this record’s narrative: “…pipe, and gas poured out. Lewis, standing by with the only light, a safety lamp, saw the place filling and called the men away; he got out himself…”

Sources

1. (secondary) Welsh coal mine fatalities, 1879 — Welsh Coal Mines
2. (secondary) Cwmdare Colliery — Northern Mine Research Society

Record created: 7 October 2026 · Last researched: 7 October 2026