Page:Walker (1888) The Severn Tunnel.djvu/133

74 their deaths were due to bad ventilation and the fumes of dynamite.

We had not used dynamite in that work at all; but the death of these men made me very anxious to adopt the best possible method of ventilation, and Mr. Wales, the Government Inspector of Mines in South Wales, was good enough to pay a visit to the tunnel to inquire into the whole matter, and to give me his advice; in consequence of which I purchased a Guibal fan, 18 feet in diameter and 7 feet wide, which was fixed at the top of the New Pit at Sudbrook.

The whole of the head-gearing of this pit was boarded in with close boarding and felted, and the entrance to it was obtained by two pair of folding-doors, so that when the fan was at work it exhausted the air from the tunnel up the shaft, and a good current of air was set up through the whole of the workings; the fresh air being drawn in at the Sea-Wall Shaft (2¼ miles from where the fan was fixed) as soon as the long heading was completed under the river.

The new shaft at Sudbrook was also fitted with two large iron cages, each large enough to contain four of the skips loaded with rock, or forty men, or two horses or ponies; and by using these large cages the quantity of rock, etc., drawn up from the tunnel was increased, and the time occupied by the men in changing shifts very considerably shortened.