Page:Walker (1888) The Severn Tunnel.djvu/127

68 It has been mentioned before that the Great Western Railway Company, before the contract was let to me, had not only commenced the heading westwards from the Old Pit, into which the Great Spring broke, but had also commenced a heading eastwards, on the formation level of the tunnel. The lower or long heading was driven from the Old Pit at such a level as to drain the lowest part of the tunnel under the ‘Shoots’ on the original gradients. This other heading, which was directly over it, and about 40 feet above it, was driven on the gradient of the tunnel, descending 1 in 100 towards the river.

As the water was lowered this was the first part of the works we were able to explore. At a very short distance from the shaft it passed through coal-shale, and there we found that the timber had not been sufficiently strong to support the pressure of the shale. The timbers were broken, and the heading was filled up with the débris. We cleared this heading out and descended to the farthest point to which it had been driven, which was 864 feet from the centre of the Old Pit. We found that in order to drain the heading several bore-holes had been put down from this heading into the long heading, and, as soon as we had secured the timbering through the coal-shale, we broke up a shaft from the long heading at the extreme end of the upper one to give the men a second means of escape, should any further accident occur.

As soon as the water was out, and the lining of