Crimea Colliery explosion, 1858

In August 1858 firedamp exploded in the Crimea or Cyfing pit at Ystalyfera, belonging to Thomas Walters of Swansea, as twelve men who had been sitting and smoking by naked lights near the shaft bottom rose to start work. Six were killed, among them the overman, David Jones, and his sons of fourteen and twelve, and three were injured. The inspectors found the western workings unventilated.

Cause

Gas accumulated in the stalls at the top of the slope in the unventilated western workings and was fired by a naked light. The pit had no proper upcast: the furnace stood at the top of the shaft, drawing its air from the surface, and a door left open sent the air short.

What happened

The men went down at about seven in the morning and, as usual, sat down to smoke before starting work. David Jones, the overman, who was paid extra to see that all was right underground, had tested for gas only near the shaft bottom. At about ten past eight they rose to begin, John Morgan going ahead with a lighted candle, and the explosion followed. Four were killed at once and two died later that day; three were injured and three escaped unhurt. David Jones left two children who had now lost both parents.

Investigation & inquiry

The inquest opened at the Bush Inn, Ystalyfera, before the coroner Charles Collins. The manager, Rees Thomas, admitted the cross-headings were dangerous, that gas had been reported and that he had not given the men copies of the rules. The inspectors Thomas Evans and Lionel Brough found the western workings unventilated and the colliery 'unsafe, defective and dangerous'. The jury found accidental death but that the colliery was not properly ventilated and some blame lay on Rees Thomas; the owner and agent were later fined £35 with expenses for failing to inspect the pit before the men went down. The London Standard attacked the jury's leniency.

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 was on Wednesday 18 August 1858. (disputed) ²
• The explosion was on 11 August 1858. (disputed) ¹

Recorded claims

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

• An explosion of firedamp at the Crimea (Cyfing) pit, Ystalyfera, in August 1858 killed six men. ^1,2,3
• The explosion was on Wednesday 18 August 1858. (disputed) ²
• The explosion was on 11 August 1858. (disputed) ¹
• The twelve men in the pit used naked candles, not safety lamps, and had been smoking before work. ^1,2,3
• The jury returned accidental death but found the colliery not properly ventilated and the manager partly to blame. ¹

Related terminology

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

• Firedamp (contextual relationship)
  Named in this record’s summary: “In August 1858 firedamp exploded in the Crimea or Cyfing pit at Ystalyfera, belonging to…”
• Naked Light (contextual relationship)
  Named twice in this record, first in the summary: “…of Swansea, as twelve men who had been sitting and smoking by naked lights near the shaft bottom rose to start work. Six were killed, among…”
• Overman (contextual relationship)
  Named twice in this record, first in the summary: “…the shaft bottom rose to start work. Six were killed, among them the overman, David Jones, and his sons of fourteen and twelve, and three were…”
• Shaft (contextual relationship)
  Named 3 times in this record, first in the summary: “…twelve men who had been sitting and smoking by naked lights near the shaft bottom rose to start work. Six were killed, among them the overman,…”
• Stall (contextual relationship)
  Named in this record’s cause: “Gas accumulated in the stalls at the top of the slope in the unventilated western workings and was…”

Sources

1. (secondary) NMRS: Cyfing Colliery Explosion, Swansea, 1858 — Northern Mine Research Society
2. (primary) The Merthyr Telegraph, 21 August 1858: Explosion of fire damp, six men killed — Welsh Newspapers Online (National Library of Wales)
3. (primary) Monmouthshire Merlin, 4 September 1858: The recent colliery explosion at Ystalyfera — Welsh Newspapers Online (National Library of Wales)

Record created: 11 October 2026 · Last researched: 11 October 2026