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I. — Description Of The Colliery
The Whitehaven Colliery is situated on the outskirts of the town of Whitehaven in Cumberland, and close to the sea shore.
The present owners of the colliery, Messrs. Bain and Co. (Mr. J. B. Bain, Colonel Bain, and Mr. J. S. Simpson), have leased the colliery from Lord Lonsdale for a term of 31 years from August 1888.
The colliery comprises three mines, viz., the Wellington, William, and Ladysmith pits, the relative positions of the Wellington and William pits being shown in Plan I., Fig. 1. There are two shafts at the William Pit, three at the Wellington, and two at the Ladysmith. The Ladysmith pit is not connected with the Wellington pit ; there was an old road but it is closed. The William and Wellington pits are connected by road which comes, roughly, under the west pier and joins the Wellington pit return airway. This road is used by the men for travelling from the Wellington to the William pits. All these mines are working the same seam, viz., the Main Band, which is the best seam at the colliery. There is a certified manager fro the Wellington and Ladysmith pits and another for the William pit, and a separate under-manager for each of the three pits.
The Wellington mine, which was, I believe, first worked in 1843, and with which this report is alone concerned, is worked by three shafts, namely the Wellington shaft (downcast) which is 9 feet in diameter and sunk to the six-quarter seam and to a depth of 894 feet, the pump shaft, also a downcast, which has a like depth and is 8½ feet in diameter, and the upcast pit 12 feet in diameter but sunk to only a little depth beyond the Main Band seam. There is also an entrance into the mine known as the Bearmouth drift, a highly inclined road, which passes by the Duke pit (an old shaft) and comes out to the surface near the coach road. A certain amount of fresh air goes down it into the mine and some men travel by it. Coals are wound to the Wellington shaft, which is fairly dry.
The Wellington pit passes through the Main Band seam at a depth of 611 feet 10 inches from the surface ; but the present winding eye (inset from which coals are wound) is 149 feet 9 inches lower down, viz., at a depth of 761 feet 7 inches from the surface,* and the seam is reached by means of a stone drift as shown in Plan I., Figs. 2 and 3. A section of the shaft with the positions of the seams passed through, and the three "eyes" or "insets" is shown in Plan I., Fig. 3. From the pumping shaft water is pumped to the surface from the Six-Quarter level.
Besides the Wellington pit there were means of raising men at pump shaft but not at the upcast.
The Duke pit is an old shaft which was cut off from the workings some time ago, but at the surface there is a fan, and fan and shaft are available for use should anything go wrong with the upcast shaft or fan. Plan I., Fig. 4, gives an average section of the Main Band seam at the mine. It will be observed that the seam is a thick one, they being no less than 10 feet 1 inch of coal or a total height of 11 feet 4¾ inches.
The seam dips away under the sea at the moderate incline of about 1 in 20, so that the inbye extremity of the main intake road — which has a westerly direction — that is 3¾ miles from the bottom of the Wellington pit, it is 1,386 feet from the sea bed and practically the whole of the workings are under the sea. See Plan I., Fig. 2. The furthest-in working place in the mine, viz., the extremity of the 6th North District is slightly over four miles from the shaft bottom. I know of no mine in the United Kingdom or abroad the workings of which extend for so great a distance away from the shafts.
System of working. — The system of working is that known as the "bord and pillar," which consists of first driving roads rectangularly to form pillars (called "whole" workings), and afterwards — sometimes not until the formation of a district has been completed, sometimes whilst it is in process of formation — working off the pillars (called "broken" or "robbery" workings) and allowing the roof to fall as the coal is worked out and the support removed. The pillars are of a size of from 25 yards by 30 yards to 30 yards by 40 yards. The bords were six yards wide, and the pillars were usually worked off by lifts five yards in width driven to the rise.
The mine is divided into several districts, but at the time of the accident coal was being worked only in three of these, viz., the 3rd, 5th, and 6th North ways, the junctions of which with the main road are respectively 2¾, 3?, and 3½ miles distant from the bottom of the Wellington pit as measured along the main intake, which is also the main haulage road of the mine. The total daily output of coal from the mine was from 800 to 850 tons, to which output the districts contributed in the following proportion :—
| 30 | per cent from the | 3rd | North. |
| 14 | " " " | 5th | " |
| 46 | " " " | 6th | " |
The 3rd and 6th North Districts were, therefore, the most important.
The 6th North was being worked in the whole, in the 5th North the pillars were being removed, and in the 3rd North both whole working and the removal of pillars were being prosecuted. In the fourth district — Saltom — though no coal work was being carried on the management had for the last four years been engaged in proving a fault, and, having found the seam, were driving two drifts to the coal, but at the time of the explosion they were making a permanent road there and preparing for the electrical haulage.
The character of the roof in the Main Band is of interest, and may have had an important bearing on the cause of the explosion (see p. 26). In some parts of the mine this consisted of a thick bed of hard sandstone rock, in other parts of a kind of "blaze" rock of a softer and more pliable character, and much more liable to fall when the coal was removed from beneath it. Thus the roof of Nos. 1 and 2 brakes in the 3rd North was hard and strong where the "robbery" workings were being carried on. The same mode of working had been followed further on in the 3rd North, and also in part of the 5th North, and here the roof had fallen easily, being composed of the softer rock.
Use of explosives. — In the 4th North no work was being done. The district had been cut off by a fault, and in order to work the coal beyond the same a cross-cut stone drift was being driven, dipping 1 in 6. This stone drift was the only place in the mine in which shots were fired the explosive used being "samsonite" (a "permitted" explosive) which was electrically fired. The shots were fired by the overmen ; and on the day of the explosion this had been done in the second shift — that is the one which had left the pit just prior to the explosion — by the overman of that shift Thomas Graham.
Underground haulage. — The system of mechanical haulage was performed by means of an endless rope, 11,000 yards long, carried from the surface down the shaft to a point just opposite the 3rd North way end, where it drove some sheaves (known as the "friction gear") from which other ropes were carried into several districts, so that the movement of one of the ropes caused the movement of the others. The tubs attached to the endless ropes were run in sets of 20. The speed of the main rope was about three miles an hour, that of the subsidiary ropes 1½ miles an hour, that is when coal was being hauled, but when men were being conveyed in- or out-bye the main rope worked at a speed of from five or six miles an hour. The haulage of the coal near the face was by "hand-putting" there being no horses or ponies in the mine, and in the 3rd North the hand-put coal was conveyed to the 3rd North endless rope by means of two, self-acting inclined planes or "brakes" down which sets of 20 tubs at a time were run, pulling up an equal number of empty tubs. The coal tubs were attached to the endless rope on the level and hauled out to the 3rd North way-end and up along the main haulage road to the shaft, the coal from the two other districts of the mine being similarly hauled. There was no "brake" road in the 5th North but there was one in the 6th North. In the 3rd North there was in addition to the "brakes" a "dilly" road (see Plan II.), in which a rope acted in the same way as the "brake" ropes, except that on one side a balance tub was used pulled up by the full one going down, the balance tub in descending pulling an empty one up. The drift men in 3rd North used a windlass for drawing stone out. Along the mechanical haulage roads were wires for signalling and telephoning. The telephone receivers were, one at "Benks' Turn", one at the "Lock Shop" ("friction gear"), and one at the 5th North junction. The wires were carried into the 3rd North also. Some of the officials were provided with pocket portable apparatus for taking telephone messages at certain spots.
It will be seen from the plans that the main intake makes two decided bends the commencement of the second bend, a distance of about two miles from the shaft being known and frequently alluded to in this Report, as "Benks' Turn". About a quarter of a mile in-bye from Benks' turn is a spot which is known as the "fan-site", as it was here that an underground fan was being erected to act as an auxiliary ventilator. Up to a point about 200 yards out-bye side of the fan-site there is but one intake air road, but at this point there is a second intake known as the "South Back Dip" which continued to run parallel to the main haulage road for a distance of about half a mile.
There were therefore, two roads out from the workings to the shaft as far as the point at which the South Back Dip commences, viz., the main intake and the return airways ; from this point there were three, the main intake, the south back dip, and the return airway**. The average inclination of the main haulage road from the shaft to the end of the road is, as has been said, about 1 in 20, but from the "fan-site" to the "friction-gear" about 1 in 9. This part of the road is known as the "Main Dip" and part of it has an inclination of 1 in 5.
All separation doors between the intake and return were locked, the officials and deputies being provided with keys for unlocking them, but in the case of extreme emergency the doors could have been broken down without difficulty. A miner might well hesitate however before taking a step so drastic. A type of lock is, therefore, to be recommended which is capable of being opened without the use of a key from the return side. Locks of this kind are in use at some collieries, e.g. the Charlaw and Sacriston Collieries in Durham.
There are small feeders of water on the main haulage road which make the road rather damp for short lengths. These feeders occur at spots where the road is crossed by faults. There was such a feeder between the "fan-site" and the "friction-gear," the water running down the main dip ; and again at a point between the 3rd and 5th North way ends. There were pumps worked by compressed air, one situated at Hillday, one at Saltom, and another at "West-end" (see Plan I.).
The seam itself would be described as dry, and in those workings where the pillars have stood for some time, as in the 3rd North for instance, where they are being worked off (robbery workings), the workings would be distinctly dry and somewhat dusty also, but in the 6th North (whole workings) the coal did not make dust, for it was firmer and not as dry as in the robbery workings where the coal is friable and might be described as invariably dusty.
Dust from the screens on the surface is carried down the mine with the intake air, and extends inbye for 800 to 900 yards, so that this dust did not get into the same area affected by the explosion. Dust also was shaken out of the tubs in their transit from the face to the shaft. Conclusive evidence was forthcoming at the Inquiry to the effect that a good deal of dust was produced in the mine. The water made at the "main dip" was filled, to the extent of about 300 gallons a shift, into iron water barrels. Sometimes it was used for watering the main roads, and sometimes hauled out-bye and drawn up the shaft. That there was no systematic watering of watering or clearing up of dust practised at the colliery was very clearly shown at the Inquiry, and it was stated in evidence by the Assistant General Manager that "he thought that" on the day preceding the explosion the 3rd North haulage road was dry. "They lifted the dust and they watered it now and again when the manager thought it necessary." The 3rd North haulage road was the dustiest in the pit, and was dry throughout.
* Depths from the surface are given as to the bottom of seam or eye
* But evidence at the Inquiry shewed that the workmen were unaware that the South Back Dip was available as a travelling road. It was not a very good road and was seldom travelled by the officials.
