H—47

The armouring marked by various indentations, which could have been caused by falling debris, became very soft towards the break, where it appeared to have been subjected to the most heat. At a distance of 5 ft. 11 in. from the broken end of the cable there were two irregular holes of f 6 - in. and \ in. diameter burnt in the armouring, and 4 in. nearer the break there was a small burn on the edge of the outer steel armouring tape. The tapes were welded together at these holes with an -J in. lap (refer Photo 8). Loose Piece of Armour A piece of armouring which proved to be the continuation of the last preceding piece was discovered in the fire wreckage, the condition of the ends indicating that it had been cut away from the main cable. This piece was, unlike the others, stretched out so much that it was possible to measure the actual length between points of damage, which consisted of the complete severing of the outer tape with a lap of § in. welded together (refer Photo 9), the partial severing of the inner tape with a lap of f in. welded together (refer also Photo 9), and, 6 ft. away, two holes f in. and | in. in diameter with a welded lap of f in. (refer Photo 10). At the brick wall end of the break two short conductors had burnt terminations and the others showed mechanical breaks. The armouring was very soft and pliable, and where the cable passed over the brick wall the armouring had been flattened presumably by falling debris. Between the first and second brick ivalls where the cable passed along a trench dug at ground-level there was a protective covering of timber and asphalt, and here the cable was virtually undamaged. Between the second brick ivall and the switchboard the cable seemed to have been subjected to a lesser degree of heat, and where running along a wooden bearer towards the 0.C.8. the lead sheath was again intact, and at the 0.C.8. the outer serving, though charred, was still intact. Lapping of Armouring The layers of steel tape armouring each If in. wide were originally laid on the cable with a space of f in. between adjacent edges, which would mean that the outer layer overlapped the inner by |- in., whilst the pieces of damaged armouring under inspection showed the following laps: §in., fin., fin., and fin. This would indicate that the layers of armouring were not in their normal position when welded together at these points. Possibility of Electrical Damage Conductors.— The pointed termination of the short conductor and the marks on the adjacent conductor, on account of their clear definition, were possibly of electrical origin brought about as a result of the action of the fire on the cable. Were they caused by the actual heat of the fire it would be reasonable to expect a more gradual degree of melting without any clear definition of the marks. The same type of marks were apparent at the brick wall end of the break where two short conductors had burnt ends.

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