The Severn Tunnel/Chapter 4
CHAPTER IV.
THE FINAL STRUGGLE.
The final struggle—1880.The 35-inch pump and the 75-inch engine being ready for work on the morning of the 14th October, No. 2 Bull-engine with the 26-inch pump being also in a condition to do about two-thirds duty with the drop-clack in it, which had been put down the rising-main, and the 41-inch engine with the 18-inch plunger-pump being able to do a little, though possibly not more than quarter duty, these three pumps were started at eleven o’clock on the morning of the 14th, for the final struggle with the water.
As nearly as we could tell, the sluice in the tubbing and the iron door above it were both closed. The water stood at tide-level, which was 38 feet 6 inches below the surface of the ground. The stage near the bottom of the Iron Pit covering the sump was about 190 feet below the surface.
To test the large pump it was started running only four strokes per minute. This was increased to seven strokes per minute on the 16th, eight strokes The final struggle—1880. on the 17th, nine strokes on the 18th, and gradually up to ten and a half strokes; the greatest speed at which we allowed this large pump to run being eleven strokes per minute.
After an hour’s pumping the water in the Iron Pit was lowered nearly 30 feet, and there was still sufficient leakage going on through the closed sluice and door to lower the water outside the Iron Pit (that is, the water which was in the heading and the other pit alongside) 6 feet. In six hours from the time of starting the pumps the water was down 88 feet in the Iron Pit, and 9 feet throughout the whole of the works.
After twenty-four hours pumping the water was down 121 feet in the Iron Pit, and 24 feet throughout all the workings, and four and a half hours later the Iron Pit was clear down to the stage over the sump, the water throughout the workings standing at a depth of 24 feet lower than it had been before we commenced pumping.
As soon as the stage was reached we took out the broken H-piece and lowered the new one, which had been provided to repair No. 1 26-inch pump. This pump was ready to work at midnight on the 16th. No. 1 was started and No. 2 stopped; the drop-valve was drawn out of the rising-main and the top valve of No. 2 pump put in its right place and properly secured. The two pumps were started together on the 19th, but another stoppage of six hours was necessary on that day to repair a broken The final struggle—1880. joint in the valve door-piece of No. 1. On the 26th another stoppage was necessary with this pump for ten hours to repair a joint which had blown in the H-piece, but the pumping was continued steadily with fair results. On the 19th we had opened the door partially to take more water from the works, and on the 20th the water stood at 54 feet from the surface of the ground in both the pits. For the next seven days the pumping continued without incident, the lowest point to which we were able to reduce the water being 128 feet from the surface in the Iron Pit and 126 feet from the surface through the rest of the workings.
It being then evident that the power we had at command was barely more than sufficient to ‘hold’ the water, I decided to fix two additional 15-inch pumps in the Old Pit, and to add an 11-inch pump to the 41-inch beam-engine; and at the same time I decided partially to close the door in the tubbing and to hold it by a wedge which could be withdrawn at any time, so that if anything further went wrong with the pumps in the Iron Pit we could close the door by withdrawing the wedge, and so make whatever repairs were necessary.
In order to fix the door in the iron tubbing in the way in which I wished to do it, it was necessary to let the water again rise to a level in both pits, so that on the 28th October, after these arrangements were made, the water was only 65 feet from the The final struggle—1880. surface of the ground in both pits. Pumping was continued steadily, and by the 31st the depth from the surface in the Iron Pit was 155 feet, and throughout the workings 150 feet. On the 2nd November the water was down 161 feet in the Iron Pit, and 154 feet 6 inches in the other parts of the workings.
I then determined to endeavour to shut an iron door in a head-wall, which had been built by the Company in the long heading under the river about 1,000 feet from the bottom of the shaft, which the men in the panic on the first breaking in of the water had left open. The diver to do this work would only work under a head of 30 feet of water. He would have to walk up the heading 1,000 feet from the bottom of the shaft, drawing his air-hose after him, and when he reached the door he would have to go behind the door, which opened inwards, and shut down a flap-valve upon an 18-inch pipe; come back through the door, pull up two rails of the tramway, close the door after him, and then screw down a 12-inch sluice-valve which was on another pipe on the north side of the door, when all communication with the further part of the heading under the river would be completely cut off.
As it was impossible for one diver to drag so long a length of hose as 1,000 feet after him up the heading, three divers were engaged. One stood at the bottom of the shaft to pass the hose, which was floating hose, round the bend from the shaft into the heading; the two others then started up the heading The final struggle—1880. for a distance of 500 feet, where one remained to pull forward the hose and feed it to the leading diver.
The leading man, in whom I had thorough confidence, was named Lambert.
He started on his perilous journey armed with only a short iron bar, and carefully groped his way in total darkness over the débris which strewed the bottom of the heading, past upturned skips, tools, and lumps of rock, which had been left in the panic of 1879, until he reached within 100 feet from the door, when he found it was impossible to drag the air-hose after him, as it rose to the top of the heading and its friction against the rock and the head-trees offered greater resistance than he could overcome. He, however, would not give up without an effort, and he pluckily sat down and drew some of the hose to him and then started on again, but after one or two vain efforts he found it impossible to proceed, and was obliged to return to the shaft defeated.
About this time I had heard of a diving-dress, patented by a Mr. Fleuss, by the use of which the diver was able to dispense entirely with the use of the air-hose, by carrying in a knapsack on his back a supply of compressed oxygen gas, which he was enabled to feed to his helmet as required.
After Lambert’s failure to reach the door on the 3rd November, I telegraphed for Fleuss to bring his patent dress and try if he could do the work. The final struggle—1880. On the 4th he arrived, full of confidence in the success of his attempt.
All the instructions which could be given to him were given, and on the 5th Lambert and he descended into the heading, Lambert with the ordinary dress and the air-hose to start Fleuss fairly up the heading, and to encourage him. After three attempts on the 5th November, it became evident that Fleuss had not sufficient practice as a diver, or confidence in himself, to go so far up the heading; with some difficulty I persuaded Lambert to put on Fleuss’s dress and try how he could work in it. After spending half an hour under water in this dress, Lambert returned fully satisfied, and undertook, with a little more practice, to make another attempt to get to the door, and he started to do so on the 8th.
Knowing the obstacles he would have to meet on his way, it was not without considerable anxiety that I saw Lambert start, for he would have to climb over the skips and other things before mentioned in total darkness, and I had to give him many cautions to be careful that the knapsack, on which he depended for air, should not strike the roof of the heading or any of the timbers and fracture the small copper pipe which led air from his knapsack to his helmet.
On the afternoon of the 8th, Lambert succeeded in reaching the door. He pulled up one of the rails and removed it, but having then been absent some The final struggle—1880. time, and feeling no doubt nervous from the novelty of the experiment he was making, he returned again to the shaft without shutting the door.
Still full of confidence, he started again on the 10th, and reached the door again in safety, went through, and let down the flap-valve, pulled up the other rail, and closed the door.
He then screwed round the rod of the sluice-valve the number of turns he had been told it would take to shut it, and returned safely and in triumph to the shaft.
On this journey he was absent one hour and twenty minutes, but he showed no sign of exhaustion on his arrival at the surface.
The water at this time stood 174 feet from the surface in the Iron Pit, and about 6 feet higher in the rest of the workings.
How anxiously we watched the floats which told us the level of the water, and how great were our disappointment and annoyance when we found that it still continued to go down at the rate of only about 3 inches an hour, and even at high tide in the river to stand stationary for some hours.
The 18-inch plunger-pump in the Old Pit had been badly out of repair during the whole of this pumping. Two or three attempts had been made by Lambert to pack the stuffing-box under water in his diver's dress. The first time he did it, it only stood for half an hour, the second time for four or five hours, and at last we had to give up this attempt to repair the 18-inch pump as hopeless.
The final struggle—1880. By 5 p.m. on the 11th November the water was down 184 feet from the surface, and the stuffing-box of the 18-inch plunger being then above water, we managed to pack it, though the men in doing so were working under a perfect cataract of water falling from the upper heading behind the shield.
The men were so sanguine now, that the principal foreman issued an invitation to the Company’s inspector, Mr. Jackson, and others, to walk up the long heading with him on the 12th. On that day the water was all out of the Iron Pit, but there was a depth of 5 feet still in the heading outside it. We began then to open the door in the tubbing wider; but when it was full open and the water in the Iron Pit held to the level of the stage, there was still between 3 and 4 feet in the heading.
Just when we felt assured of success, on the 13th, No. 1 26-inch pump had to be stopped for repairs. Two days later No. 2 had to be stopped to pack the piston of the engine, and on the 19th the door-piece of No. 2 pump split; but having a new one ready we only stopped the pump two hours.
From the 19th November to the 1st December, No. 1 pump was under repair, and the water had again risen to 80 feet from the surface.
When repairing No. 1 pump, we took out the double-beat valves with which it had worked up to that time, and replaced them with four-beat valves, which worked much more smoothly.
At 6. p.m. on the 1st December the whole of the The final struggle—1880. pumps were started again, and the water was lowered as follows:
| Iron Pit | Rest of the Workings. | |||
| Depth from surface— | 2nd Dec., at | 12 noon | 127 feet | 124 feet |
| ”” | 2nd”” | 6 p.m. | 135” | 132” |
| ”” | 3rd”” | 12 p.m. | 150” | 148” |
| ”” | 4th”” | 12 p.m. | 162” | |
| ”” | 5th”” | 12 p.m. | 174” |
and on the 6th December the water was all out of the Iron Pit and there was only two feet of water in the heading outside it.
On the 7th the foreman of the Cornish pumps, James Richards, was able about midday to walk up the heading to the door which the diver Lambert had shut, and then he found the cause of our disappointment at not gaining upon the water as soon as Lambert had succeeded in shutting the door.
The rails were properly pulled up and removed, and the door was properly closed. The flap-valve on the pipe on the south side of the door was also shut, but the sluice-valve on the other side had a left-handed screw, and the valve must have been closed when Lambert reached it; and when he had given it the right number of turns to close the valve, instead of closing it he had opened it to its full width. Richards at once screwed down the valve, the effect was felt immediately, and the pumps were then slowed down.
Several other members of the staff took advantage of the news brought by Richards, and went down at once to explore the headings. The final struggle—1880. No one but those who have been engaged in such a struggle can imagine the delight of all hands at the victory which it had taken us nearly twelve months to win.
On the 13th December, the principal foreman of miners, Joseph Talbot, had the doors in the shields over the western heading opened, and explored the heading for a distance of nearly 600 feet; and on the 14th Mr. J. Clarke Hawkshaw and myself, accompanied by Talbot, went through these doors and made a second exploration of the heading. We found a stream of water 7 feet wide and about a foot deep flowing down the heading; and certainly it was a novel experience to pass through the doors in the shield and get into the heading. We were all clothed in divers’ dresses, with ‘sou’-westers’ instead of helmets; and standing on the stage by the door, over the sill of which about 10 or 12 inches of water was running, we had to put one leg through and sit down in the water while we gathered the other leg after us, and came into a standing position in about 3 feet 6 inches of water at the back of the door. From the farthest point we could reach, we could see the broken timbers where the water had first burst in. A great quantity of débris had been brought in by the spring, and at about 600 feet from the door this filled the heading to a depth of between 3 and 4 feet, so that if we had wished to go farther we must have gone on all-fours. The air, too, proved bad, and lights were with difficulty kept burning; so we .jpg)
selected a place where the rock seemed sound for building a head-wall to stop back the water from the spring, which we decided to undertake at once.
To execute this work it was necessary to make two dams across the heading with good clay, and between the two to carry the water in wooden troughs about 3 feet square. Under the troughs a chase was cut well into the bottom of the heading; chases were also cut on both sides and in the roof, and in these a strong head-wall of brickwork, in cement 8 feet thick, was built with a door-frame of 12-inch timbers, and hooks to hang the door. The 3-ft. troughs passed through the door-frame, and when the brickwork was completed the shoots were removed and the door hung, but left open.
The bricks, cement, and timber had to be taken up the heading on a rough raft pulled backwards and forwards by a rope; and before any of these things could be done, an air-pipe had to be laid and a supply of compressed air provided for the men.
The brickwork was finished, and the door hung by about the end of the year 1880; and after allowing time for the brickwork to set, the door was closed on the 4th January, 1881, and the water from the spring entirely shut out from the works. This head-wall was 469 feet west of the centre of the Old Pit, and for more than two years from the time the door was shut we had no more trouble from the spring itself.
The final struggle—1880. Thus ended the year 1880, the first year of the works.
It was well for us that we had not known all the difficulties we were to encounter when we entered on the work, almost with a light heart, on the January previous.
In addition to the work in the tunnel considerable progress had been made in providing dwellings for the men, and other things for their accommodation. On the first plot of leased land six large houses had been built, which were each capable of holding two married couples and about twelve lodgers. Six smaller houses to accommodate a married couple and six or eight lodgers had been erected, as well as small houses for a married couple and two or three lodgers or children, and a number of semi-detached houses of a better class had been provided for foremen. A very good house, situated close to the shaft and the bank of the river, had been built for the principal foreman, Joseph Talbot, and was occupied by him and his family.
The brickyard had been thoroughly started, and the large crushing-mill for crushing the hard shale for making blue bricks was nearly completed.
A mission hall had been built, and arrangements made for a supply of preachers, principally from the Evangelization Society, and services were held on Sundays and Wednesdays. A day-school for the children had also been opened, and was in full working order, as well as a Sunday-school, which was The final struggle—1880. attended before the end of the year by forty children.
A good driving-road had been made from the shaft to the nearest public road, near the ‘Black Rock Hotel,’ and encouragement had been given to the various tradesmen in Chepstow and Caldicot; and from this time to the completion of the works the men were as well supplied with all the necessaries of life as if they had lived in an old town; tradesmen and farmers’ carts of all descriptions calling at all the houses nearly every day.
Other land for houses had been leased, and also land for a second road leading in the direction of the villages of Portskewett and Caldicot, Arrangements had been made with the Great Western Railway Company to allow a timber bridge for this road to be thrown over their South Wales line; and the erection of the bridge was in progress.
The heading between the door, which had been shut by Lambert, and the bottom of the shaft being rendered useless as a drainage heading by the lowering of the gradient under the river, it had been intended that after the works were completed it should be filled up with rough masonry or concrete; but on a careful examination of the heading itself, it was found that in some places it was in a very dangerous condition. For part of its length the heading was driven in the Pennant sandstone; but it also passed through beds of coal-shale, and being very lightly timbered, was in a very bad state, and for four years The final struggle—1880. it was necessary to use it as the only means of access to the works.
It was therefore arranged by Sir John Hawkshaw that, instead of ultimately filling up this heading, it should be at once lined with brickwork, being first enlarged so as to leave a circular adit, 9 feet in diameter, inside the brickwork. This it was proposed should be used, when the tunnel was completed, as an auxiliary passage for ventilation, leading to a fan which should exhaust air from the tunnel.