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OPEN LIGHTS.

As to the possibility of existence of open lights it will be remembered that no naked lights were allowed to be used. The types of lamp in use were good and safe, and those that were recovered uninjured by the explosive force were found to be in a satisfactory condition. There was no evidence or even suspicion of misuse, but up to the 20th of May there were 12 safety lamps still unrecovered; of these two belonged to the Towneley seam, one to the Tilley seam, and nine to the Busty seam. Of the unrecovered lamps one of the two in the Towneley seam belonged to a man whose body was found under an extensive fall of stone, his lamp is probably under that fall. Five of the nine lamps missing from the Busty seam belonged to hewers who were working in the bottom section of that seam. The water rose in this section of the seam after the explosion and it is probable that the missing lamps are in the water. The remaining lamps belonged to the two men whose bodies have not been recovered. All the lamps brought out of the mine after the explosion were very carefully examined, but no trace of any damage was found in any lamp which could have been from an internal cause, nor is there any evidence forthcoming of matches having been taken into the pit or of other means for improperly obtaining a light.

SHOT FIRING.

The careful system in operation at the colliery in respect of shot firing and all appertaining thereto has already been described. A very careful search was instituted for the magneto shot-firing apparatuses, shot and detonator boxes, and when found a careful examination was made of the same. All were accounted for, and in no case was it possible to connect them with the firing of a shot. Every shot hole was examined with like result, and we regard it as satisfactorily proved that no shot was fired either at the time of or immediately prior to the explosion.

SPARKING FROM MECHANICAL FRICTION.

Another suggestion of the possible cause of the explosion was made by the Coroner, and is alluded to in the evidence of Mr. P. Kirkup, viz., that sparking caused by the set coming out of the Busty West way might ignite a cloud of coal dust, and so initiate an explosion. Mr. Hall, the manager of the colliery, gave it as his opinion, in answer to questions put to him by the Coroner, that such was possible, and went even further, putting the sequence of events as – tubs off the way, a cloud of coal dust, fall of stone, sparks, explosion ; but a little consideration will show the untenability of this theory.

It must be borne in mind that in the cases which were quoted in support of the theory, the conditions were quite different. The sparks were being continuously generated, and the coal dust in the neighbourhood in which the sparks fell smouldered and was doubtless gradually fanned into flame; and the fact remains that a Sub-committee of the French Fire-Damp Commission made experiments with marsh gas and firedamp (the latter obtained from the workings of a colliery) which would be much more easily ignited than the finest and most inflammable of coal dusts, and producing sparks by means of a mechanical drill and hard stone failed to inflame the gas. Sparks also produced by pressing a bar of steel against a rapidly revolving emery wheel – a dazzling and continuous shower – failed to ignite a very large jet of an inflammable mixture of air and marsh gas and of air and firedamp directed into the sparks.

ELECTRICITY.

As regards electricity, before due weight can be given to the pros and cons some technical knowledge is necessary. There can be little doubt that the jury must have felt this in considering their verdict, and for this reason, however carefully that verdict may have been considered, and on this point there can be no doubt in the present instance, it cannot be held to carry as much weight in this direction as attaches to it in other directions. In these circumstances it becomes the more necessary to carefully examine the possibilities opened out by the presence of electricity in the mine.

We have satisfied ourselves that none of the coal-cutting machines were at work at the time of the explosion.

The hauling motor in the Towneley seam and the pump motor in the Busty seam close to the downcast shaft were running at the time of the explosion, and these appear from the evidence to have been the only two motors which were running. Each was found to be in order after the accident, and therefore the possibility of any motor having caused the accident apart from the other electrical apparatus must be rejected.

The electric lights were burning in the Busty seam shaft siding prior and subsequent to the explosion (vide the evidence of Matthew Elliott, onsetter in this seam), and lights in the Towneley seam would be burning too, though there is no direct evidence to show this.

From the fact that after the accident all the fuses in the mine were found to be intact, it was very generally agreed in the course of the investigations preceding the inquest, and even during the inquest, that electricity could only be regarded as a remote first cause. It came out in evidence, however, that a main cable near a gate-end box in the Towneley South District had on an occasion about four months before the accident been the cause of considerable sparking – sufficient indeed to completely sever one core of a three-core cable, which core had been previously damaged by a fall of roof – without the fuse opening circuit. Mr. Richard Heslop, the colliery electrician, was cross-examined on this point :–

It is therefore clear that under the conditions which obtained at West Stanley Colliery previous to the accident sparking external to a cable was not invariably followed by the blowing of a fuse. No part of the electrical system was, we understand, connected to earth. The fact is therefore not extraordinary, but the conclusion is important as discounting the value of any argument based upon the fact that all the fuses in the mine were found to be intact after the explosion.

It was also sought (vide evidence) to attach some weight to the fact that by the evidence of Matthew Elliott (the survivor from the Busty seam) electric lamps were burning for a few seconds, or it may have been only the fraction of a second, after the explosion. This point was c1eared up in cross-examination of Dr. Thornton :–

We have then two points upon which reliance has been placed in rejecting electricity as a possible cause more or less destroyed – the first by experience at this very colliery, and the second by a mere consideration of the way in which the electrical circuits were actually run.

Dr. W. M. Thornton, Professor of Electrical Engineering at the Armstrong College, Newcastle-on-Tyne, who was called by the Durham Miners’ Association, and who practically committed himself to the opinion that the explosion had had an electric origin, gave three possible points of origin :–

He fixed upon the third as being the most likely, and mentioned in particular "a junction box in the Busty West seam on the North side just before reaching the small three-throw pump ; this box is in court, smashed, electrically disembowelled."

Since the inquest one of us has seen three of the fuses which were in the junction box mentioned in particular by Dr. Thornton. All of them are intact and show no sign whatever of heat, nor do their cases.

A further theory which in the absence of definite proof found considerable favour, is that the explosion originated in the Busty seam at a point some distance inbye of the curve indicated by Messrs. Blackett, Tate, and Kirkup. According to this theory the set of full tubs in coming out got off the way, and either then, or immediately afterwards, knocked out some of the timber, allowing the roof to fall and creating a dense cloud of dust; simultaneously the electric cables were injured by abrasion and an arc formed which ignited the dust and so caused the explosion. Such an occurrence is possible if the arc was formed at the exact moment that the dust was in suspension at the spot, but at the best it can be only a conjecture. It is not considered likely that any explosive gas could be present, but the unlikely does occur, and it is possible that a small quantity may have been liberated or brought down by the fall and this may have initiated the explosion. One of us has also since the inquest been able to examine the cables in question, but he was unable to find any marked sign of electrical damage or of fusing; the damage the cable had suffered was external, probably due to falls of roof and other causes; on the other hand there can be no doubt that the effect of an explosion might very easily remove all visible trace of the original injury.

On the assumption that the explosion did originate in the Busty seam, we are of opinion that electricity is a more likely first cause than any of the alternatives already discussed.

We desire to draw attention to the six recommendations, suggested by the evidence at the inquest, and contained in the Memorandum with which we have been furnished by Mr. Nelson, the Electrical Inspector of Mines (See Appendix C). Mr. Nelson made many underground inspections at West Stanley subsequent to the disaster and overhauled the electrical machinery, and we wish to acknowledge the great assistance he has been to us in respect to this side of the question.