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Inspection and Investigation after the Explosion

Inspection after the explosion revealed that the coal in Bailey's place had been kirved to a depth of some 4½ feet right across from side to side; and that two shot-holes had been bored, one 22 inches from the left side, and the other apparently about the same distance from the right side, both being started about 8 inches from the roof. The hole on the left side was 4½ feet deep and had not been charged; that on the right, which had been bored to 3 inches into the solid, had been charged and fired but little work had been done, the "Cardox" cartridge having been blown out leaving a socket about 15 inches deep.

This cartridge, with a piece of cable still attached, was found on the floor next the face of the place opposite, i.e. the one in which McGlennon and Walsh had been working. The exploder was found on Bailey's level, the key and an electric safety lamp being beside it; the body of William Cowan, who had evidently operated the exploder, close by; and the bodies of Armstrong, Walsh and Vincent, two flame safety lamps and an electric lamp some few feet further outbye. See Plan 2.

The shotfiring cable was found in three pieces, one some 16 feet long, with the two leads at one end formed into loops, a few feet outbye from, and on the opposite side of the road to, the exploder, another piece about 7 feet long some distance outbye, and the third piece, 105 feet long, stretched out along the road, also outbye from the exploder, with its outer end entangled with some iron rapper wire around the hook and wheel of an upturned tram.

Such of the brattice as still remained was scorched and some of it fell to pieces on being touched.

Two empty tubs were found, one standing in the place opposite Bailey's, the other standing derailed at the outbye side of the flatsheet at the crossing. Through the outer end of this latter tub there was a hole and beneath this hole the top edge of the middle hoop had been bevelled for nearly 3 inches and one of the handles on the tub end had been twisted into the hole. See Photograph, Plate No. 1.

There had been no stonedusting done at and about the face of Bailey's place prior to the firing of the " Cardox" shell, although there was within 8 yards of the face of that place a bag of stone dust for the purpose.

Examination of Lamps.

The two flame and two electric safety lamps found in Bailey's level were sent to the Mines Department Testing Station, Sheffield, for test by the Superintending Testing Officer, Captain C. B. Platt. Captain Platt, in evidence, described the tests to which he had subjected these lamps and stated that, in his opinion, none of them was responsible for an ignition of inflammable gas.

Examination of Dust.

After the explosion, 72 samples of the dust on the roof, floor and sides of the roads in the No. 3 North District were collected from selected spots by Mr. W. B. Brown, Junior Inspector, and Mr. R. Butler, Sub-Inspector, and sent to Captain Platt for determination of combustible matter.

The determinations by Captain Platt showed that, on the average, the samples taken from the sides contained 34 per cent. ; those from the roof 38 per cent. ; and those from the floor 44 per cent. combustible matter. It is difficult to reconcile these figures with the average of those obtained from the samples taken during 1930 by the management, namely :– Roof 11 per cent. ; Floor 19 per cent.; and Sides 13 per cent, combustible matter.

The explanation would appear to be that considerable quantities of coal dust had been stirred up by the explosion, due to overturned tubs and from nooks and crannies unreached by the stone dust applied prior to the explosion.

Examination of Exploder and Cable.

The exploder and cable used for the firing of the Cardox cartridge in Bailey's place were examined and tested by Professor R. V. Wheeler. It was found that the exploder, when filled with a firedamp-air mixture, on being operated, ignited that mixture; also that, when a similar mixture surrounded the exploder, as well as being contained within it, the external mixture was ignited by the ignition of the internal mixture, flame emerging through holes in the casing. It was also found that if the conductors from the exploder were allowed to come in contact and then separate whilst current was flowing, the sparks so produced ignited a firedamp-air mixture.

The cable was taken underground on 27th January, and had only been used to fire 3 shots.

When found in Bailey's level after the explosion the conductors at one end of the sixteen feet length were formed into loops ‐ presumably for passing over the terminals of the exploder.

Mr. Morgan, the Agent, said he thought that the cable had been damaged prior to the explosion and that only the longest length of 105 feet was being used at the time of the explosion, and that the other two pieces – the 16 feet piece and the 7 feet piece – were lying at the side of the road.

Against this view, as Mr. Morgan agreed, the terminal screws of the exploder were found screwed tight home and, on account of the shock which would be received, it would not be likely for a shotfirer to hold the straight ends of the cable on to the terminals of the exploder; he would have to make loops and the only loops that were found were those at one end of the sixteen feet length of cable. It would therefore appear that the cable had been damaged by the explosion and not before. But even with this cable in perfect condition before the explosion, there would still remain the possibility of a spark occurring between its bare ends where attached to those of the firing leads of the Cardox shell.

Examination of Cardox Cartridges.

Two Cardox cartridges, the spent one found in the face opposite Bailey's and the other, a fully charged one, found near the body of William Cowan, were sent to the Safety in Mines Research Station, Buxton. They were examined and all parts were found to be in order.