Deep Navigation Colliery roof fall, 1914

A fall of roof 28 feet long on a double parting at Deep Navigation Colliery, Treharris, on 25 June 1914 killed one man outright and fatally injured another.

Cause

The roof fell over 28 feet after a bridge of ground had been ripped down on a double parting.

What happened

On 25 June 1914 men at Deep Navigation Colliery, Treharris, had just ripped down a bridge of ground on a double parting when the roof fell both in front of and behind them, over 28 feet in all. John Jones was killed outright. The repairer John Thomas, 55, was badly hurt and died on 30 June, and a third man was injured.

Recorded claims

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

• On 25 June 1914 a fall of roof on a roadway at Deep Navigation Colliery, Treharris, killed John Jones outright and fatally injured the repairer John Thomas, 55, who died on 30 June. ^1,2
• After the men had ripped down a bridge of ground on a double parting, the roof fell in front of and behind them for a total length of 28 feet. ^1,2
• Another man was also injured. ^1,2
• The colliery belonged to the Ocean Coal Co. Ltd. ²

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: “A fall of roof 28 feet long on a double parting at Deep Navigation Colliery, Treharris, on 25 June 1914 killed one man outright and fatally…”
• Roof Fall (contextual relationship)
  Named in this record’s summary: “A fall of roof 28 feet long on a double parting at Deep Navigation Colliery,…”

Sources

1. (secondary) Fatalities 1914 — Welsh Coal Mines — Welsh Coal Mines
2. (secondary) Accident record: John Thomas, Deep Navigation, 1914 — Northern Mine Research Society

Record created: 9 October 2026 · Last researched: 9 October 2026