The following page is based on materials available at the Whitehaven Record Office and Local Studies Library. It is likely that further information will be found in the Lonsdale archive at Carlisle Record Office.

Isaac Fletcher's paper for the Cumberland and Westmorland Antiquarian and Archaeological Society (Old Series, Vol. III, 1878, p286), "The Archaeology of the West Cumberland Coal Trade" contains the following short quotations from the pay-bill of Corporal Pit (aka Corpsill or Corpshill), Whitehaven, 10 August 1737:
"5th, Friday. Firedamp killed 22 at 4 o'clock in ye M."; as a result of which £8 3s 10d was spent "for searching for and taking up 22 dead and three horses, mending thirls, etc., after the Great Fire Damp." [thirls are ventilation tunnels connecting the main passages and working areas of the mine]

Unusually for Whitehaven, the event even rated a sentence in the national newspapers- but if there was at that time a newspaper published in Whitehaven itself, no copy has survived, so we must rely on other sources to find more about this disaster. The most detailed account comes from the official records of colliery owner Sir James Lowther, in letters written to him by his agent, John Spedding (available on microfilm JAC341). According to his first letter on the subject, written within hours of the disaster, it occurred within the old workings at Corporal Pit, and was, in the first analysis, the result of the workmen having had too much to drink at the town's Fair (drunkenness being, in his opinion, the cause of "most of the great misfortunes we have ever had"). However, his more detailed explanation tells a slightly different story.

In theory, there were a number of colliery employees whose sole task was to keep the miners away from coal-faces ("heads") where hazards such as fire-damp had been reported. In practice, on this particular day, some of the face-workers chose to ignore safety instructions and work where the coal-getting was easiest, so that they could fulfil their daily quota as quickly as possible and get back to the Fair. One of these easy but unsafe locations, in the South Endgill of the Corporal Pit workings, was the source of the explosion. When the colliery manager, John's brother Carlisle Spedding, was called out, at around 5am, he and his son [unnamed, but it would be James, aged about 17] found conditions appallingly dangerous. They managed, at great risk, to rescue one man, but of the 20 or so known or presumed to be dead, 7 or 8 were men who had gone in to try and save their colleagues after the initial fire had died down, only to suffocate. Also dead were three horses belonging to John Harison.

By the afternoon, 11 corpses had been found, and 12 others were unaccounted for. Presumably other bodies were recovered during the night, as funerals were held the next day for the following people:
At Holy Trinity Church: Timothy Robinson, John Ridley, William Gamel, George Dixon, William McMullen, and John Gordon.
At St. Nicholas' Church: James Page, Thomas Westray, John Salkeld, David Gordon, John Harrison, Jonathan Smith. William McMullen, Robert Benn, Andrew Warlock, John White, James Coupland, Richard Troutbeck, George Dixon, Abraham Watson, and Elizabeth Moor.
Also at St. Nicholas' Church, on 7 August: Arthur Graham.
Note the recurrence of some names, almost certainly close relatives working together.

In another letter written on 10 August, John Spedding reported that miners all over Whitehaven were reluctant to return to work. In the end, on 9 August, Carlisle Spedding had personally led some workers into the "Farr Pitts" and checked every working head for safety. Work resumed at Saltom Pit on 10 August, but there remained a problem that the owners of the pit horses would not send them in to haul out the coal, so some of Sir James Lowther's own horses were employed instead. As for Corporal Pit itself, it was evident that a great deal of persuasion would be needed to get men to clear out the damaged area. The seat of the explosion had been "on the Dip side of a Dyke that we crossed w'th the 2d Waggon Inbank", and Spedding acknowledged that it would not be possible to resume working there at all, but even on the rise side of the said dyke, the damage to the roof, props etc. presented major challenges. And the stench of noxious gases still pervaded the whole pit, to the extent that even the men repairing the gin [winch] at the pit top could barely stand it. Carlisle Spedding's lungs were affected, as were his son's, leading him to consider getting the lad out of the colliery business before it was too late.

On receipt of John's first letter, Sir James Lowther immediately ordered £100 to be distributed among the families of the victims, and notified him that he was willing to meet "any charges" for research to combat the fire-damp menace (quoted in "West Cumberland Coal", by Oliver Wood- CWAAS Extra series 24, 1988, p42). It was probably this event which led young physician Robert Brownrigg, who had qualified in Leiden at the beginning of 1737, and came to work in Whitehaven that spring, to begin research into the nature of fire-damp. In this he was encouraged both by Sir James and by John Spedding and his brother Carlisle, who arranged for the gas from one particularly large pocket of fire-damp to be piped directly to his laboratory [information about his research, with a description of the Whitehaven mines some years later, can be found in "The Literary Life of William Brownrigg", by Joshua Dixon, 1801]. What is not clear is whether Carlisle Spedding's invention of a rotating wheel to generate sparks which gave light without generating enough heat to ignite the fire-damp was a result of this event (spark lighting by flint and steel is referred to in a paper Sir James wrote about fire-damp for the Royal Society in 1733, but the precise mechanism is not explained). As Whitehaven's mines spread further and deeper, their joint efforts failed to solve the problem; in 1744 John Spedding observed that Brownrigg's work was "of Singular Use to my Br.", but that still "the works grow worse and worse" (quoted in Wood,1988, p42). Though it would be many years before Whitehaven suffered another disaster on the scale of 1737, miners continued to be killed by fire-damp, and Carlisle Spedding himself died in an explosion in 1755.