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The section switch controlling the electrical supply to the 3rd East Flat was "ON" at the time of the explosion, and hence all the cables inbye of it to the respective gate-end switches were alive but only the turbine pump was running. Batteries were not being charged at the charging station and no other apparatus was working in the 3rd East Flat.

The bodies of the four missing men were found in the 3rd North road in close proximity to an auxiliary fan which, during the shift on which the explosion occurred, must have been transferred from a point inbye of the 3rd North bank of gate-end switches (compare Plans Nos. 2 and 3). Shuttle car No. 924, found at the top of the 3rd North, had undoubtedly been used during this transfer. The fan was lying in the 3rd North road near the sixth stenton to the right, which was open and along which lay a length of canvas tubing with one end close to the fan but not coupled to it; the fan was connected by a trailing cable to its proper gate-end switch, the isolator of which, as was that of the other fan, being in the "ON" position. The switches themselves were "OFF", with the respective leakage protection flags showing: subsequently this was attributed to the violence of the explosion. No other apparatus appeared to have been working inbye of the gate-end switches. The circumstances strongly suggested that an attempt was being made to use the fan to speed up the restoration of the ventilation in the working places, in which it had been stagnant for the previous five days.

The shuttle car No. 924 was located at the junction of the 3rd North road and the 7th Level (K.31), in close proximity to the place at which it had been parked when work ceased in the district. As soon as it was found and before it was completely uncovered, it was examined by the driver who had last had charge of it, Norman Craig, and his evidence is conclusive, in my opinion, that the car had been in use during the shift on which the explosion occurred. He stated that when he parked the car he put chocks under the wheels, put the switches in the "OFF" position, the "forward and reverse" gear lever in neutral, and withdrew the battery plugs.

When he examined it afterwards, he found the car was nine feet outbye of the position in which he had left it, the chocks were missing from under the wheels, the switch was in the "run" position and the gear lever was engaged in "reverse", which in the case of a car such as this, designed to run forwards and backwards, means that it was engaged in the gear which would be required if it was moving up the 3rd North road.

When located, the batteries were found exposed and the two cover plates. each weighing one hundredweight, were found one inside the car and the other leaning up against the outside of the car. The positions in which these covers were found are very significant and in my opinion are capable of only one interpretation, namely, that they had been lifted off by one or more of the men and placed where they were found. I am unable to reconcile their positions with the suggestion that they had been blown off by the force of the explosion.

One of the battery leads of the right-hand battery, which had been changed from its terminal position at some time in order to cut out a damaged cell, had been forced down on to one of the battery connecting links by a roof fall and four cells had thereby been short circuited, the resultant arc having been so heavy and so sustained that it had melted away some of the lead connecting link (see Plates I and II). [See Plate I, Plate II]

Whether the roof fall and short circuit initiated the explosion or whether they occurred some time subsequently does not alter the fact that all the other electrical equipment in the district was found after thorough examination to be free from damage or fault, and hence the shuttle car batteries were the only pieces of equipment likely to have been the source of ignition.

Much of the evidence originally left by the explosion had been masked by falls in the road, heaving floor and water, as well as by the subsequent re-opening and repair work. Judged by isolated evidence of flame, all the places in the two Flats appeared to have been involved in a firedamp explosion. Few signs of violence were seen, although the force of the explosion wrecked the overcast and travelled to a corresponding point on the return airway. The conveyor and some of the apparatus in the charging station were displaced and moved in a northerly direction. Evidence of coking was found but was not in any sense densely distributed, and it was clear that coal dust had played no material part in the propagation of the explosion. There was clear evidence from witnesses that the district had been filled with inflammable gas for some days before the explosion occurred, and hence there is no doubt as to the source of the firedamp.