The Severn Tunnel/Chapter 5
CHAPTER V.
Progress of the work—1881.The year 1881 opened under brighter auspices than its predecessor; the water from under the river being entirely excluded by the head-wall and door which had been built by the Company, and on the 4th January the water from the big spring also being shut out by a head-wall and door as before stated. For double security we proceeded to build, inside each of these, a second head-wall; the one in the western heading being about half-way between the first one and the shaft, and the other one as close as we could place it to the head-wall under the river.
By building these second head-walls, all the small leakage which had come through the first was stopped out from the works.
The work of enlarging the existing heading, to line it with 18 inches of brickwork, and leave a 9-ft. barrel, was commenced; and it was well that all these precautions were taken, for a new Progress of the work—1881. of danger confronted us, which we had not, and could not have, foreseen.
Of course, the consumption of coal by the pumping-engines was very considerable; but as we were in communication by railway with the South Wales line of the Great Western Railway, and so with the coal-pits, we had never thought it necessary to provide any large stock of coal, when, on the 18th January, 1881, the great snow-storm, which will long be remembered in England, came upon us without warning.
I was returning to the works from London on that day, and left Paddington by the quick train, known as the ‘Zulu,’ at three o’clock. The storm was then raging furiously, but we got through to Swindon, an hour late, only to remain there snowed up all night. When the train reached Portskewett at one o’clock the next day, eighteen hours late, we found all the roads blocked with snow, and our branch railway, from the Great Western to the works, for most of its length blocked to a depth of between 3 and 4 feet. The goods traffic of the main line was entirely disorganized, and it was not till the 21st that we were able to obtain a supply of coal direct from the coal-pits.
We had been reduced to all kinds of expedients, begging and borrowing all the coal we could in the neighbourhood, and finally cutting up timber to keep the pumping-engines going. We were, however, able to do so; but it was not till the 28th that the severe frost which followed the snow-storm broke Progress of the work—1881. up, and enabled us to go on as before with the works.
All building operations on the top were, of course, stopped during this period.
The road and temporary bridge over the Great Western Railway were completed in February, and the making of vitrified bricks from the shale excavated in the tunnel was commenced in April.
The new shaft at Sudbrook, afterwards called the ‘New Winding Shaft,’ was pushed forward now that the water was out of the headings; and at the bottom of this shaft the 9-ft. heading was enlarged to an 18-ft. tunnel, to give room for extra lines of way for the skips, and to allow of the turning and handling of heavy timbers, which had to be lowered down the shaft for bars or sills.
The 9-ft. barrel-drain was completed to the head-wall under the river in April. Two feet above the bottom of the drain it was planked over, and on the planking a double road for skips was laid, the gauge of each road being 1 foot 9 inches. As soon as this was completed, and the road laid up to the first head-wall, that wall was cut away, and the sluice in the second head-wall opened gradually till all the water was drawn out of the heading under the river, when the door was opened, and the heading was explored. On the 9th May I went up this heading with Joseph Talbot. Generally, it was in a pretty good state, because the ground was very good, but there was not timber sufficient to Progress of the works—1881. hold weight if there should be any; and at about a mile and three-quarters from the bottom of the Old Pit we found the roof had fallen in for a considerable distance, and then that a great fall had come from the roof, and the whole heading was stopped.
The air-pipes which had been laid up this heading were choked by the fall of the dirt, so that the air was bad, and lights would not burn, and we had to return from our exploration, walking something like a mile in the dark before we could obtain fresh lights.
I at once made arrangements to send men up to secure those parts, where the fall had taken place, with timber. Before it was possible for them to carry lights, it was necessary to punch holes in the air-pipe at short intervals to obtain a supply of air.
It was nearly an hour’s work for men to go up, pushing trollies with timber, from the shaft to where the fall had taken place. I therefore arranged for a few men to go in, taking timber with them and food, so that they might remain at the end of the heading for the whole shift of ten hours.
The men who had been working for six years for the Great Western Railway Company before the contract was let to me had always felt a grudge against me, probably because they had had easier times under the old régime. Under the Company they had to work nominally eight-hour shifts, going to work at six in the morning, firing a round of shots in the face of the heading, loading up the material Progress of the work—1881. which had been brought down by the blasting, and then coming out. On this system three sets of men worked in each twenty-four hours, changing shifts at six in the morning, two in the afternoon, and ten at night. Each shift was allowed half an hour in the middle of the shift for a hasty meal.
I had insisted on the men working ten-hour shifts, and, during the shift, coming twice to bank for their meals.
All the work having to be done by blasting, it was dangerous for the men to return to the faces immediately after the shots had been fired, because at that time dynamite was used, the fumes of which are dangerous.
On the ten-hours system it was arranged that nearly all the blasting was done just before the men came out of the tunnel to their meals. The air was then clear by the time they went down again. The men commenced to work at six o’clock, and worked three hours. From nine to ten they came out of the tunnel, and had breakfast; going down again at ten, they worked till one o’clock; from one to two they came out to dinner, and from two till six they worked again to complete the ten-hour shift.
When the Great Spring broke in and drowned the tunnel in October, 1879, the distance from the shaft to the face of the heading under the river was 10,100 feet, or more than a mile and three-quarters. All the skips were brought out by men pushing them that distance, the men being known as ‘runners Progress of the work—1881. out.’ These ‘runners out’ had very short lengths to push the skips, and the cost, when the Company was working the heading, was more than ten times what it could have been done for by ponies, or perhaps twenty times what it could have been done for by proper hauling-engines.
There had been a bad spirit among the men from the time I had taken possession of the works. I believe they had wished that I should fail in pumping the water out of the tunnel. I am not quite sure that they had not wilfully caused some of the difficulties that had occurred; and now that the works were opened throughout, and there was a prospect of making better progress, they determined to make a stand, and either force me to abandon the work altogether, or to yield to their demands. Their discontent first showed itself by their jeering at the men who took their meals with them up the long heading, asking them why they did not get tin hats made to carry their dinners in; and then by assaulting in the darkness, or when they could meet with them alone, men I had brought from a tunnel I had just finished at Dover.
At last, on Saturday the 21st May, a notice appeared, written in chalk, at the top of the main shaft: ‘I hope the ———— bond will break, and kill any man that goes down to work.’
The men gathered round the pit, but refused to go below.
It was Saturday morning, and the pay of the Progress of the work—1881. night-gangs would commence between eleven and twelve o’clock.
I may as well state here that on Saturday the men only worked seven hours, but were paid for ten. They went down, as on other days, at six; came up to breakfast from nine to ten, and the first, or day-shift, finished at two. The second, or night-shift, commencing at two, worked only till ten, making seven hours, with one off for a meal; and the works, except the pumping, were not carried on at all from 10 p.m. on Saturday till 6 a.m. on Monday.
After refusing to commence the shift they went off to the nearest public-house, came back primed with drink, and gathered in front of the pay-office grumbling; but they never came to me or the foreman and stated any grievance or asked for any concession. They simply determined to make trouble and stop the works if they could. I was in the office at the time, so I went down into the middle of them, and said:
‘Now, what do you fellows want?’
No answer.
‘Now, tell me what you want, and don’t stop hanging about here.’
Then one of them said:
‘We wants the eight-hour shifts.’
I said: ‘My good men, you will never get that, if you stop here for a hundred years. There is a train at two o’clock, and if you don’t make haste and Progress of the work—1881. get your money you will lose your train. You had better get your money as soon as you can, and go.’
The men looked very sheepish, went to the pay-office and got their money, and the works were absolutely deserted for the following four days.
This strike, as I have said, occurred on Saturday, and the next night (Sunday) the great timber pier at the Black Rock, where the ferry steamers landed their passengers, was burnt down, and there were not wanting people to say that it had been burnt by the men on strike; but, in my judgment, they were innocent of this. There had been a long period of dry weather, the timber in the pier was very old, and, above the level of high water, very dry; and I think some pleasure-seeker on Sunday had probably thrown away a fusee after lighting his pipe, and there being a high wind at the time, the fire had spread quickly. It probably arose either from this or from the careless raking out of the fire from the boiler of the engine which was used in lifting the luggage of passengers from the steamer at the end of the pier.
It was a good thing for the works that this strike occurred when it did, for it cleared away a number of bad characters who had gathered on the works; and from this time to the completion of the contract there was hardly any trouble with the men, and I think there was a thoroughly good feeling between employer and employed.
The works were all secure below, and, the water
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| Portskewett Pier (with the Works — Sudbrook in the background) |
from both the long heading and the Great Spring having been shut out by the head-walls, one 26-inch pump was able to pump all the water, and the other 26-inch and the 35-inch were in reserve.
In order to bring a little pressure to bear upon the men on strike, I ordered all the carpenters, blacksmiths, and other men employed on the surface to be stopped on Tuesday morning. This was a blow they had not expected, and on Thursday, the 26th May, some of the men came back and asked for work. On Friday a larger number returned, and in a few days the works appeared to be going on as before, with this great advantage, that a number of bad characters had been got rid of.
The ten-hour shifts were worked on the west side of the river from this time to the termination of the work without difficulty. After the men returned to work, the slip at the end of the long heading was thoroughly secured, the heading cleaned up to the face, and we commenced to drive the 130 yards that intervened between it and the heading coming from the east.
The fall in the roof proved to be a very serious one. For a length of 50 feet it had fallen down from a height of 20 feet above the heading, and though we afterwards secured the brickwork safely through this length, we were always troubled at this point with water, which found its way into the work; for, by the breaking of the strata, fissures no doubt extended at this point quite up to the river-bed.
Progress of the work—1881. 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 Progress of the work.1881 the bottom heading commenced, we also commenced the tunnel proper in the upper heading, though the lowering had made this heading neither a top nor a bottom heading, but placed it some little distance above the centre of the tunnel.
At Sea-Wall Shaft we had commenced the tunnel itself, and the length of brick arch turned at this side of the river on the 1st January, 1881, was 93 feet.
We were also driving a bottom heading at the new levels, i.e., about 19 feet 6 inches below the old heading.
At a distance of 262 feet westwards of the Sea-Wall Shaft, we commenced on December 20th, 1880, a break-up to enable us to begin the tunnel proper at a second point. This was called ‘Sea-Wall Break-up No. 1.’ At a further distance of 200 feet from ‘No. 1 Break-up,’ we commenced on January 10th, 1881, ‘Break-up No. 2;’ and at a still further distance of 168 feet, on February 6th, 1881, ‘Break-up No. 3.’
At the end of April, 1881, the break-up length of brickwork was completed in No. 3 Break-up, and two lengths were turned, one at each end of it; the bricklayers were at work, and had nearly completed the second length east of the break-up, when suddenly the water burst in from the roof of the tunnel, and drove the bricklayers for a time away from their scaffold. This was a more serious difficulty than any we had hitherto met with, as it was salt water that came into the tunnel, and it Progress of the work—1881. was manifest that the river had to some extent broken into us.
At low water, when there remained in a pool at this point, called ‘The Salmon Pool,’ only about 3 feet of water, we completed the length of brickwork in the best way we could, stopping back the water with litter; and at the same time sent a number of men out on the foreshore of the river to see if they could find any holes by which the water had found its way into the tunnel. As that part of the river-bed was never actually dry at low water, and as it was impossible to indicate with any precision to the men the spot they were to search, a considerable time was spent fruitlessly in endeavouring to find the hole. At last, by making a number of men join hands and walk through the water, the hole was found; one of the men suddenly popping down out of sight, and being pulled out by those who had hold of his hands at either side. Having found the hole, it was only a work of time to secure it on the top; but as there was a risk that the water running through continuously might seriously enlarge it, the pumps at the Sea-Wall side were stopped, and the water allowed to rise in the tunnel to the same height as the tide outside. In the meantime clay-puddle had been prepared, and as soon as it was ready, a schooner was loaded with it and taken out at high water to the point where the hole had been discovered; at low water the hole was effectually stopped by layers of loose clay and clay in bags Progress of the work—1881. alternately, with a considerable heap of clay in bags laid over the top for the sake of weight. When this was completed, the pumps were started again, and the clay was found to have effectually stopped the water.
At each end of the lengths of brickwork, where the water had broken in, a 6-ft. length of tunnel was immediately commenced, 4 feet thick; the ordinary work being only 2 feet 3 inches. These lengths were taken out as rapidly as possible, and brickwork in cement built in them, thus forming, in the chases which had been cut, a ring of brickwork nearly double the ordinary thickness to stop the water from travelling along the back of the work. This proved entirely successful, and though we had once or twice to repair the clay puddle on the top and replace the bags, we had no further trouble with the Salmon Pool.
Later on in the work we had a similar experience with a small lake, known as ‘The English Lake,’ but there we never had the same volume of water rushing into the tunnel, and had no necessity for stopping the pumps.
It was a most fortunate thing that this bursting in of the water from the Salmon Pool occurred before the long heading was completed; for had we broken through from the long heading on the west side of the river into the heading on the east side, it would have been impossible to stop the pumps and let the water rise in the tunnel till such time as Progress of the work—1881. we could have built a wall across the heading to prevent the water flowing westwards; and as this would have taken several days to do, the rushing in of the water might have done irretrievable damage.
When the men returned to work after the strike at the end of May, as many as could work in doing it were sent up the heading from Sudbrook to secure the slip which had taken place at the east end; but before commencing to drive the heading and complete the link between the east and west sides of the river, I found it necessary to make a better arrangement for getting out the skips than the expensive method which had been followed by the Company. The men were therefore started over a long length of the heading to slightly deepen the one side of it, and to put in, at a height of about 2 feet from the bottom, a decking of 3-inch planking where it was possible to do so. In other places to build a dry stone wall to raise the skip-road above the water-level. As the heading was only 7 feet high originally, it was necessary to blow down part of the top to increase the height, as I determined not to work on this long ‘lead’ till I could get ponies to do the hauling. It was necessary also to put in heavier rails than had been originally used. These had been bridge-pattern rails, about 18 lbs. to the yard, quite unsuitable for any heavy traffic.
They were replaced with rails 42 lbs. to the yard, Progress of the work—1881. and a good road, with proper drainage, made throughout the whole length of 1¾ miles.
A system of sixty Swan electric lights was also established at the end next the shaft, and 20-candle-power lamps were fixed at distances of 22 yards apart, from the bottom of the shaft to where the first break-up was to be formed, for building the tunnel under the ‘Shoots.’ The long heading was then driven through to join the eastern side of the river, and the junction was effected at 10 p.m. on the 26th September, 1881.
Up to the time of making this junction the only system of ventilation available for us was by conveying compressed air from compressors at Sudbrook through the whole length of 1¾ miles.
Three mains were laid for this air—one 2-inch main for the men driving the heading, and two 3-inch mains for supplying compressed air to work the rock-drills in the break-ups under the ‘Shoots.’
We were using, for blasting, ‘tonite,’ made by the Cotton Powder Company, which I had selected as giving off less noxious fumes than any other explosive, except the highly-washed gun-cotton; but in the end of July two men, who had been working in the heading at the Marsh Pit, died of inflammation of the lungs, after a very short illness. The opinion of the doctors in charge was that the men died from inflammation of the lungs contracted from exposure, the headings being very wet and hot, and the men careless; but, as usual, some people were found to say that Progress of the work—1881. 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.
Progress of the work—1881. The fan gave perfect satisfaction during the period of more than four years that it was working; and the same system is adopted for the permanent ventilation of the tunnel; a 40-ft. Guibal Fan having ultimately taken the place of the 18-ft. fan which was used while the works were in progress.
At 5 miles 4 chains the heading was driven east till we reached a distance of only 26 feet from the point where the Great Spring had broken into the heading, coming westwards from Sudbrook.
The heading was almost entirely in the fire-clay shale, and was perfectly dry. The full-sized tunnel was proceeded with and pushed forward over the same length. At the same time the heading was driven westwards from the 5 miles 4 chains pit, and the full-sized tunnel commenced from break-ups at various points, as shown on the section.
At a distance of 800 feet from the shaft the heading passed from the fire-clay into the conglomerate rock, in which the driving was most difficult, both on account of the hardness of the rock and the enormous quantity of water met with. Isolated as this pit was, and short as the lengths of the headings in communication with it were, it required a 70-inch Cornish beam-engine with two 28-inch pumps to keep the workings free from water.
The brickyard which had been established was close to the top of this pit, and the crushing-mill for crushing the shale was connected with the head-gearing of the pit; so that the shale from the Progress of the work—1881. tunnel, which was brought up in skips, was run straight to the crushing-rollers, and within half an hour from the time the shale was got in the tunnel, it was made into bricks, and the bricks placed upon the floor of the drying-shed to be dried for the kiln.