Engineering Wonders of the World
Volume I

 ENGINEERING WONDERS OF THE WORLD. a heap of debris which the inrush of the spring had swept before it. It was decided to wall up the heading without delay. Two clay dams were built across the heading, and large wooden troughs laid from one to the other to carry off the water. In the dry section between them the wall was built round the troughs, and when the brickwork had set the troughs were removed and. a wooden door substituted and closed fast. The water from the spring was thus shut out entirely from the works, and for the next two years gave no trouble at all. The year 1880 ended very auspiciously. Early in 1881 there occurred the terrific snowstorm which is still an unpleasant memory to all who experienced it. Railway traffic was disorganized by the drifts, and for ten days the tunnel works were out of communication with the coalfields. Fuel for the pumping-engines ran short, and it became necessary to cut up valuable timber, as to stop the pumping would have been disastrous. A strike of the workmen broke out in May over the question of working hours, and, though, it delayed, matters for a time, had th© ultimately good effect of clearing out a number of disaffected men, who, if retained, would have made trouble sooner or latér. As soon as things had quieted down, the work was pushod on at the bottom of the Sea Wall Shaft, where several lengths of full-sized tunnel had been “ turned ” or bricked round. Everything was progressing smoothly when, without warning, salt water burst into the tunnel and drove layers. Immediately above the point of ingress there was at low tide a pool named the Salmon Pool, formed by a depression in the river-bed. Mr. Walker solved the problem of finding the leak by making a number of men join hands and wade about in the water. The sudden disappearance of one of the explorers showed its whereabouts ; and the leak was stopped 84 As the use of a hose, even with two men passing it along the heading, was impracticable, a Mr. Fleuss made an attempt with his recently- patented diving equipment, which included a supply of compressed oxygen gas carried in a vessel attached to the back, to replace the usual hose and air-pumps. But as the inventor was not a professional diver he failed of his object, and Lambert had to be persuaded to try the apparatus. At the first trial he reached the door, and removed one of the wagon rails running through it before he thought it time to beat a retreat. Two days later he de- scended again, closed the door, and screwed down the sluice, being on this occasion under water for eighty minutes. Yet even when the job had been done, the pumps seemed to have no more control over the water than before. According to calcula- tions, the closing of the door and sluice should have given them easy mastery by reducing the inflow. When at last the drainage heading was cleared sufficiently to allow an examination of the head wall, it was discovered that the sluice-valve Iiad, for some unknown reason, been fitted with a Ze/£-handed thread, so that Lambert, instead of closing an open valve, had actually opened a closed one! A few moments sufficed to correct the mistake, and the effects were immediately felt in the rapid fall of the water-level in the sump and the pumping-shafts. This trouble having been overcome, Mr. Walker now turned his attention to the Great Spring in the heading west of the Old Shaft. The door in the shield on that side was opened and the water allowed to run free. The contractor and two others on entering found a stream of water 7 feet wide and 1 foot down the heading ; and dis- at a point about 600 feet from A Curious Mistake. The Great Spring attacked and defeated. deep flowing covered that the shield the passage was almost choked by A Snowstorm causes Trouble. Irruption of River Water. off the brick-