NUNNERY. Sheffield, Yorkshire. 3rd. December, 1923.
The colliery was on the eastern outskirts of the City of Sheffield and was owned by the Nunnery Coal Company Limited. It had been winding coal since 1866 from two winding shafts, both downcast, one of which was the No.1 or East Silkstone Pit. It was on the Main East engine Plane of the workings in that pit that the disaster occurred.
The shaft was about 307 yards deep to the Silkstone Seam which dipped to the northeast at an average of about 4 inches to the yard. At the time of the accident, all the workings were to the dip of the shaft and the coal had been worked in a succession of levels from the main incline as the Main East Engine Plane. This was driven straight for 1,156 yards before dividing due east and the other part, after going eastwards for 250 yards, turned due north with both planes reaching 1,950 yards from the pit bottom. Except for short lengths here and there the East plane an average height of five feet six inches and an average width of 7 feet.
The General Manager was Mr. W.H. Mascall who also acted as agent with Mr. C.S. Magee as certificated manager. The undermanager of the Silkstone workings in which the accident happened was Mr. J.T. Bradwell who held a Second Class Certificate of Competency.
Coal was hauled up the inclines by a single main rope driven by steam engine at the surface. The rope served in turn the branches of Hewitt’s Plane and the East Plane. Men were hauled on the same rope at the beginning and the ends of each shift between the East Plane and Hewitt’s Level, a distance of about one mile. The practice of transporting men in this way had gone on for six years.
The steam engine consisted of a pair of 24-inch cylinders, of 5-foot stroke coupled directly to a drum shaft with the cranks at right angles to each other. The cylinders were supplied with steam at 50 lbs. pressure and were fitted with slide valves operated by Stevenson’s link motion. The drum was 6 feet in diameter and 2 feet 8 inches wide and ran free on the shaft unless the dog clutch on the shaft was thrown into gear. When the empty train was being lowered down the incline during coal lifting operations, the drum ran free and was controlled by the brake but when people were being lowered, the engine was kept in gear and no steam was let into the cylinder. Braking was applied by two drum straps actuated by a hand lever on brake paths fitted externally to the flanges of the drum.
The haulage rope was led from the drum on rollers to the top of the shaft and then diverted to a horizontal pulley and a vertical pulley into a range of 4-inch cast-iron pipes which ran down the brickwork lining of the shaft to the pit bottom. Here it passed through a third pulley into a horizontal wooden trough and from there to the top of the engine plane. From that point, the rope ran down the plane which consisted of a single track of fish-plated rails and to the various junctions in turn. In the plane itself, it ran on rollers fixed at intervals between the rails and at each junction four or five rollers 10 to 12 inches high were set in frames to guide the rope around the curve. These frames had the double purpose of “skating” rails to guide the tubs as they were passing around the curve.
An over-rope connected at one end of the shackle of the haulage rope and at the other to a drawbar of the last tub of the set was on the top of the train to prevent tubs from running back in the event of a break in the coupling had a back-stay drag was also attached to the last tub when the train was ascending to prevent the set running back. No person rode on the train while coal was being hauled but when men were riding, an authorised person accompanied them on a seat hung on the outside of the tub next to the rope.
In the ordinary course of coal handling, people were stationed at several junctions and were responsible for the turning pints. They saw that the train went safely around the corners and the rope stayed on the rollers. Before an empty set started from the pit bottom the destination of the set would be notified by telephone to each junction. Electrical signals were used along the whole length of the haulage plane and these were operated by rubbing a knife or something else, across the wire the number of times required by the signal. The code that was in use was:
For hauling persons:
- 8 – Men in tubs
- 5 – To draw up steadily
- 4 – To lower steadily
- 1 – To stop
For hauling coal or empties:
- 3 – To draw up
- 5 – To draw up steadily
- 2 – To lower
- 4 – To lower steadily
- 1 – To stop
Auxiliary haulages were in use at the top and bottom of the engine plane to feed the main haulage system but these played no part in the disaster.
Between 2 and 2.30 on the afternoon of December 3rd, 120 people were ready to descend the Main Haulage Plane in a set of tubs known as the “Paddy Mail”. The train was made up of 44 tubs of which 42 were for the men to ride in and as many as four men rode in some of the tubs. The usual starting point of the “Paddy Train” was opposite to the entrance to the First North level and while it was standing there a number of men entered the tubs.
A man had been injured in the workings during the afternoon and he was being carried up the plane of a stretcher. There was not enough room to allow the passage of the stretcher between the tubs and it was decided to draw up the Paddy Mail a short distance, to allow the stretcher to pass to the First North Level. The Paddy Mail was in the charge of Colin Chappell who was the main plane run attendant. He ordered the men who had taken their seats out of the tubs and signalled to the engineman “5” to draw up steadily and later “1” to stop and the train was drawn up about 40 yards. The one hundred and twenty men the entered the Paddy Mail and after the stretcher party had cleared the plane, Chappell signalled “8” to the engineman to signal that the men were in the Mail and then “4” for the Mail to be lowered steadily.
The engineman obeyed the instructing and the Mail ran normally at about three miles per hour at first but when it had travelled about 40 yards it seemed to be speeding up. The haulage man, Harry Scott who was standing by noticed this and shouted to Chappell to give the engineman the signal “4”. Chappell did this by drawing together the overhead signal wires and placing his knife across them. He had not realised until Scott had alerted him that the train was going too fast. Both the engineman, Walter Stockton and his assistant, Walter Proctor, who was standing at the reversing lever and operated when it was required when men wee being lowered, stated that the signal “1” meaning stop was received in place of “4” which Chappell had tried to send. Proctor pulled over the reversing lever and the engine smoothly pulled up by the brakes stopped in 18 feet. The engineman and his assistant then noticed that the rope was slack and that the load had come off it.
Chappell thought he had signalled “4” but the signal that was received at the engine house was “1” and that immediately as the signal was received the haulage rope broke. The Mail gathered speed down the incline and crashed in Cain’s Junction, 377 yards from the starting place. Some of the tubs jumped the rails and seven men were killed, eight seriously injured and forty-seven received minor injuries.
Those who died were:
- William Thomas Birch aged 53 years, collier. Died from injuries to the body
- Charles Bowden aged 62 years, collier. Died from a fractured skull
- John Henry Turner aged 49 years, collier. He had fractured both legs
- Bernard Newton aged 18 years, haulage hand. Died from injuries to the head and body
- Charles Needham aged 60 years, collier. Died from a fractured neck
- Charles White aged 37 years, collier. Died from a fractured spine
The inquiry into the disaster was held in the Council Chambers in the Town Hall in Sheffield and opened at 11 a.m. on the 7th May. It lasted two days and seventeen witnesses were called. It was held by Sir Thomas H. Mottram, C.B.E. formerly H.M. Chief Inspector of Mines and presented to Mr. E. Shinwell, Esq., M.P. Secretary for Mines on 11th. August 1924. All the interested parties were represented and evidence was presented that the haulage rope had been spliced several times:
- From the capel to the 1st splice, a length of 300 yards was spliced on the 24th April 1922
- 1st splice to 2nd splice, 480 yards, 18th September 1922
- 2nd splice to 3rd splice 580 yards, 8th January 1923
- 3rd to 4th 480 yards, 9th April 1923
- 4th to 5th 480 yards, 14th June 1923
- Ten yards were ignored and the total length of the rope was 2,330 yards.
The use of appliances to stop trains ascending or descending an incline in the event of the rope failing were examined and since the disaster, these had been installed at the colliery and the testing of haulage ropes apart from the manufacturer’s certificate was considered and the desirability of providing a separate road for the haulage of men was also considered. The signalling system was examined and the Inspector commented:
The method of transmitting signals by bringing the two electric wires together appears to have been effective, though the carrying of an open bladed knife for this purpose was a practice which is by no means commendable. Some other form of an instrument could easily be devised.
Sir Thomas Mottram summarised his conclusions and recommendations:
- The disaster was caused through the breakage of a part of the haulage rope which had been in use 19 months, but as previous ropes of similar make and type had been used for a longer period without accident, and daily examination in addition to the statutory weekly examination had not disclosed to the officials any defects apart from ordinary wear and tear to be expected. I do not wish to attach blame to the Management in respect of the broken rope.
- I am not satisfied that all the examinations of the haulage rope were as thorough as they might have been, nor do I consider that the weekly statutory reports made by appointed persons always complied strictly with the requirements of Section 66 of the Coal Mines Act 1911 in the respect that defects discovered were not recorded, in other words, the statutory reports were not full and accurate. The explanation given was that when fractured wires were discovered, or when splicing was found to be necessary, the defect was remedied and the rope made good, and thereafter a report was made that the rope was in good order. The omission to record defects was liable to mislead higher officials as to the true behaviour or state of the rope and it is possible that if the reports had been full and accurate the rope might have been suspected before the accident took place.
- I am of opinion: That the provisions of Section 66 of the Coal Mines Act 1911 should be amplified so as to require a daily examination of machinery, gear and other appliances of the mine used for hauling persons below ground, and that all defects, whether fond during a statutory examination or at any other time, and the steps taken to remedy them, should be recorded in the book already required to be kept at the mine.
- That splicing of ropes used for the haulage of persons on inclined planes should be prohibited.
- That the maximum life of ropes used for the haulage of a person on inclined planes should be limited to 18 months.
- That an effective safety appliance to arrest the set in the event of the rope breaking should be installed on every train or set used in hauling persons on inclined planes underground.
- That the question of a factor of safety for passenger haulage ropes, and as a corollary, the question of making inquiry into the use and manufacture of such ropes, should be referred to the Safety in Mines Research Board for advice.
- That the provision of a separate road for the haulage of men is a matter deserving of the consideration of mine managers.
- That General Regulations should be made to cover Nos. 3, 4, 5 and 6 of the foregoing recommendations, and also to specify the type of tram or carriage to be used, the maximum number of persons to be carried at one time in each tram, and the maximum speed at which the journey should run.
Report on the causes of and the circumstances attending the underground haulage accident at the Nunnery Colliery, near Sheffield on the 3rd December 1923, by Sir Thomas H. Mottram, C.B.E. formerly H.M. Chief Inspector of Mines.
Colliery Guardian, 4th January 1924, p.48.Return to previous page