Page:Walker (1888) The Severn Tunnel.djvu/78

Rh held down, jumped out of its seat and would not work.

Arrangements were made at once to lower in the Old Pit a 15-inch pump to help to hold the water down till the shields were fixed.

The shield to close the western heading was made with two doors opening as flaps into the heading; the size of the opening of each door was 2 feet 3 inches by 1 foot 6 inches. On the 14th we found, to our surprise, that the top valve of No. 2 pump had, from vibration or some other cause, gone back to its seat again, and we re-started the pump; but on the 16th, to add to our troubles. No. 1 pump, which had hitherto been working well, broke down utterly, and the pump was useless.

It was impossible to attempt to repair this pump under water, and our only hope then was that we might be able, by closing the door and the sluice at the bottom of the Iron Pit, to empty the pit and then repair it. If the shaft had been properly constructed there should have been no difficulty in doing this, the shaft being tubbed with iron to within 10 feet of the bottom. Unfortunately the lower 10 feet was lined with brickwork only 18 inches thick. This was cut away on the north and south sides of the shaft to receive the iron girders and the sluice, and the brickwork had not been properly made good round these. We therefore found every effort that we made to clear the pit of water futile. More water