CADBEY MAIN. Denaby, Yorkshire.
In response to a question from Peter Mitchell.
The colliery was the property of the Denaby and Cadeby Main Collieries, Limited and was in the Don Valley in South Yorkshire, almost midway between Doncaster and Rotherham; the collieries were about 2,000 yards apart. The area of mineral tract worked by the Colliery Company was about ten thousand acres.
The Denaby and Cadeby Main Collieries were under the general control of a Managing Director, Mr. W.H. Chambers, who was well known throughout Yorkshire and the Midlands as a Mining Engineer of a high standing and experience. He lived near the collieries and took a more active part in the management of the mines than was usual for a Managing Director. Mr. H.S. Witty was the Agent over the two collieries and previous to this appointment in September, 1911, he had been manager of the Cadeby Main Colliery. Under Mr. Witty, as manager of Cadeby Main alone, was Mr. C. Bury who was seriously injured in the second explosion and died a few days afterwards. There was one undermanager at the mine. Mr. Bridges, an assistant undermanager, Mr. Cusworth, killed in the second explosion and Mr. Eli Croxhall, who also lost his life in the second explosion, acted as undermanager on the afternoon shift.
There were two shafts at the Cadeby Main Mine which was close to Conisborough Railway Station and were sunk to the Barnsley bed which was the only seam that was worked at the mine at a depth of 763 yards on the dip side of a large fault which had a throw to the south of 126 yards. The coal on the north side of the fault was won by a pair of headings which were driven through the fault. The mine produced about 3,000 tons per day and the coal was wound at both shafts. The No.1 was the downcast and the No.2 was the upcast both 16 feet in diameter and 752 and 738 yards deep respectively.
The coal was wound from the bottom of the No.1 shaft and the coal was brought to a temporary inset on a level with the seam on the north side of the fault at the No.2 shaft. An inset was being made at the bottom of this shaft but had not been completed. Some of the coal worked on the north side was brought to the No.1 shaft and this was lowered down by a staple pit sunk from the north side level to the south side level.
The Barnsley Bed had Bind roof and floor of fireclay or shale and about 7 feet 3 inches thick of coal was worked. About 49 feet above the Barnsley Bed was a seam of coal 2 feet 2 inches thick but the top coal of the Barnsley Bed was of an inferior quality and mixed with dirt. The Barnsley Bed was known to be a gassy seam but at Cadeby it was not subject to blowers or sudden interruptions of gas. The undermanager, Mr. Bridges, told the inquiry that after a weighting in the No.2 Pit, about two years before the accident, it was necessary to withdraw the whole of the workforce from the mine on account of the gas.
In South Yorkshire the seam was liable to spontaneous combustion and the colliery had suffered no less than 35 fires and to work it, it required great care and vigilance on the part of the management. The seam dipped at 1 in 14 to 1 in 12 to the south west and the workings were divided into five man districts, the First North, the Second North, the East, the South and the West Districts. The coal was worked on the longwall system and the distance between the gateroads was usually 40 yards. Packs were built on either sides of the roads for a width of 7 feet 6 inches, and every seven yards a gob pack was built, 6 feet wide. The material used to build the packs was stone got from the wastes and from the rippings in the gates. In the main roads, a good deal of ripping had to be carried out in the bind roof which had the effect of forming stone dust. This had a great limiting effect on the propagation of the resulting explosions. All the coal was got by hand and there were no mechanical coal cutting machines nor conveyors used to transport the coal along the faces. The coal was friable and there were quantities of coal dust made at the face.
No shots were fired except in the stone drifts and then only at weekends when there were few persons in the pit. As an additional safeguard only the manager was permitted to fire the shots. The mechanical haulage of the coal was in the main intakes and the haulage system used an endless rope which was electrically driven from the bottom of the shaft. The secondary haulage was done by horses and ponies.
The ventilation of the mine was by a Schiele fan, 21 feet in diameter which ran at 119 r.p.m. at a water gauge of about three and half inches. A Waddle fan, 9 feet in diameter and electrically driven, was kept as a standby after being replaced by a reversible Sirocco fan. Although the Cadeby Main mine was connected to the Denaby mine by means of an emergency outlet, the ventilation system of the two mines was quite separate and the iron doors at the outlet were kept locked.
With the exception of some of the lamps carried by officials and a number of electric lamps used when working at fire holes, the colliery used Marsaut lamps. After the accident, safety lamps were found in the explosion area and found to be intact but several found on the 14 level were broken and one in 19’s crossgate had been broken from the outside.
The surface arrangements were designed to prevent the coal dust from tipplers, screens, conveyor belts and hoppers from being carried down the downcast shaft. The dust was collected by funnels attached to pipes which were in turn connected to an exhaust fan which created a two and a half inches water gauge pressure. The dust laden air was passed from the fan into a cyclone where it entered a steamy atmosphere maintained by a steam jet from the boilers. This arrangement, which had been in operation for about five years, had proved most effective in clearing the air about the Hempstead from dust and practically none was carried down the downcast shaft into the workings.
In each district there was a senior ‘ charge’ deputy who worked with an afternoon and night shift charge deputy. The senior, and more experienced of the charge deputies, was on the morning shift which was the most important shift of the three. The afternoon and night shift deputies were considered inferior to the morning deputies only in that they received their instructions from the undermanager through the senior deputies.
They had the same duties and responsibilities as the morning deputies. Besides these there were assistant deputies, two to a large district and one to a small district. These men assisted the charge deputies and examined and reported as if they were full deputies.
The examination before the commencement of work in the morning shift was made by the night deputy and his juniors and they each reported the results of their examinations.
All the deputies and their assistants were carefully and wells selected. Generally speaking the charge deputies were drawn from the assistant deputies.
The mine was worked on three shifts, two coal getting shifts and one repairing shift.
The first coal getting shift was from 6 a.m. to 2 p.m.,
the second from 2 p.m. to 10 p.m.
the repairing shift from 10 p.m. to 6 a.m.
The deputies went down with the men in the first cages.
938 men worked underground on the 8th July 10 p.m., 7th. July, to 6 a.m.
505 men 8th. July 6 a.m. to 2 p.m., 2 p.m. to 10 p.m.
52 men 10 p.m. to 6 a.m.
11 men 9th. July.
The numbers working on the corresponding days of the previous week were
489 men 10 p.m., 30th. June to 6 a.m.,
853 men 1st. July. 6 a.m. to 2 p.m.,
238 men 2 p.m. to 10 p.m.
The difference in the numbers on the 2 till 10 shift was accounted for by the fact that H.M. the King visited the neighbourhood on the 8th and 9th and many people made it an occasion for a holiday.