Kilsby Tunnel

London North Western Railway:

Midland Railway:

Stratford Midland Junction Railway

The Shakespeare Route

Kilsby Tunnel

Northamptonshire

Kilsby Tunnel is a railway tunnel on the London and Birmingham Railway which was opened in 1838 and forms part of West Coast Main Line railway. The tunnel is located near the village of Kilsby in Northamptonshire approximately 5 miles south-east of Rugby and is 2,426 yards in length. There are ten ventilating shafts each of nine feet in diameter, and two large shafts of sixty feet diameter, these latter being surmounted by impressive castellated towers . The tunnel took far longer, and cost significantly more money to build than had been anticipated. This was because the tunnel roof collapsed and the tunnel flooded unexpectedly due to quicksand which trial borings into the hill had not revealed. The excess water from the quicksand had to be pumped out, a process which took some eight months. This shouldn't have been a complete surprise as similar problems were encountered with nearby Blisworth tunnel on the Grand Union Canal a few decades earlier. The length of time it took to build the tunnel delayed the opening of the London and Birmingham Railway resulting in a stage coach service to be used to move passengers between the two completed sections of the line. It took three years, and cost £320,000 to build which was three times the original estimate. It is reported that approximately 30 million bricks were used in construction. Around the turn of the century the inner lining was giving cause for concern, the remedy being to reline with Staffordshire blue brick. It was designed and engineered by Robert Stephenson and it is today the 18th longest tunnel on the British railway system.

The construction of the tunnel has been recorded by Samuel Smiles in his 1879 autobiography of the Stephenson's. The section relevant to the tunnel, pages 246 to 252, is provided below.

LIVES of the ENGINEERS
GEORGE AND ROBERT STEPHENSON

BY SAMUEL SMILES (1879)

Though not the largest, this is in many respects one of the most interesting works of the kind in England. It is about 2400 yards long, and runs at an average depth of about 160 feet below the surface. The ridge under which it extends is of considerable extent, the famous battle of Naseby having been fought upon one of the spurs of the same high ground about seven miles to the eastward.

Previous to the letting of the contract, the character of the underground soil was examined by trial-shafts. The tests indicated that it consisted of shale of the lower oolite, and the works were let accordingly. But they had scarcely been commenced when it was discovered that, at an interval between the two trial-shafts which had been sunk, about 200 yards from the south end of the tunnel, there existed an extensive quicksand under a bed of clay 40 feet thick, which the borings had escaped in the most singular manner. At the bottom of one of these shafts the excavation and building of the tunnel were proceeding, when the roof at one part suddenly gave way, a deluge of water burst in, and the party of workmen with the utmost difficulty escaped with their lives. They were only saved by means of a raft, on which they were towed by one of the engineers swimming with the rope in his mouth to the lower end of the shaft, out of which they were safely lifted to the daylight. The works were of course at that point immediately stopped.

The contractor, who had undertaken the construction of the tunnel, was so overwhelmed by the calamity, that, though he was relieved by the Company from his engagement, he took to his bed and shortly after died. Pumping-engines were then erected for the purpose of draining off the water, but for a long time it prevailed, and sometimes even rose in the shaft. The question then presented itself, whether in the face of so formidable a difficulty, the works should be proceeded with or abandoned. Robert Stephenson sent over to Alton Grange for his father, and the two took serious counsel together. George was in favour of pumping out the water from the top by powerful engines erected over each shaft, until the water was mastered. Robert concurred in that view, and although other engineers pronounced strongly against the practicability of the scheme and advised its abandonment, the directors authorised him to proceed; and powerful steam-engines were ordered to be constructed and delivered without loss of time.

In the mean time, Robert suggested to his father the expediency of running a drift along the heading from the south end of the tunnel, with the view of draining off the water in that way. George said he thought it would scarcely answer, but that it was worth a trial, at all events until the pumping-engines were got ready. Robert accordingly gave orders for the drift to be proceeded with. The excavators were immediately set to work; and they were very soon close upon the sand bed. One day, when the engineer, his assistants, and the workmen were clustered about the open entrance of the drift-way, they heard a sudden roar as of distant thunder. It was hoped that the water had burst in—for all the workmen were out of the drift,—and that the sand bed would now drain itself off in a natural way. Instead of which, very little water made its appearance; and on examining the inner end of the drift, it was found that the loud noise had been caused by the sudden discharge into it of an immense mass of sand, which had completely choked up the passage, and prevented the water from flowing away.

The engineer now found that there was nothing for it but to sink numerous additional shafts over the line of the tunnel at the points at which it crossed the quicksand, and endeavour to master the water by sheer force of engines and pumps. The engines erected, possessed an aggregate power of 160 horses; and they went on pumping for eight successive months, emptying out an almost incredible quantity of water. It was found that the water, with which the bed of sand extending over many miles was charged, was to a certain degree held back by the particles of the sand itself, and that it could only percolate through at a certain average rate. It appeared in its flow to take a slanting direction to the suction of the pumps, the angle of inclination depending upon the coarseness or fineness of the sand, and regulating the time of the flow. Hence the distribution of the pumping power at short intervals along the line of the tunnel had a much greater effect than the concentration of that power at any one spot. It soon appeared that the water had found its master. Protected by the pumps, which cleared a space for the engineering operations—carried on in the midst, as it were, of two almost perpendicular walls of water and sand on either side—the workmen proceeded with the building of the tunnel at numerous points. Every exertion was used to wall in the dangerous parts as quickly as possible; the excavators and bricklayers labouring night and day until the work was finished. Even while under the protection of the immense pumping power above described, it often happened that the bricks were scarcely covered with cement ready for the setting, here they were washed quite clean by the streams of water which poured from overhead. The men were accordingly under the necessity of holding over their work large whisks of straw and other appliances to protect the bricks and cement at the moment of setting.

The quantity of water pumped out of the sand bed during eight months of incessant pumping, averaged 2,000 gallons per minute, raised from an average depth of 120 feet. It is difficult to form an adequate idea of the bulk of the water thus raised, but it may be stated that if allowed to flow for three hours only, it would fill a lake one acre square to the depth of one foot, and if allowed to flow for one entire day it would fill the lake to over eight feet in depth, or sufficient to float vessels of 100 tons. The water pumped out of the tunnel while the work was in progress would be nearly equivalent to the contents of the Thames at high water, between London and Woolwich. It is a curious circumstance that notwithstanding the quantity thus removed, the level of the surface of the water in the tunnel was only lowered about 2½ to 3 inches per week, proving the vast area of the quicksand, which probably extended along the entire ridge of land under which the railway passed.

The cost of the line was greatly increased by the difficulties encountered at Kilsby. The original estimate for the tunnel was only £99,000; but before it was finished it had cost more than £100 per lineal yard forward, or a total of nearly £300,000. The expenditure on the other parts of the line also greatly exceeded the amount first set down by the engineer; and before the works were finished it was more than doubled. The land cost three times more than the estimate; and the claims for compensation were enormous. Although the contracts were let within the estimates, very few of the contractors were able to complete them without the assistance of the Company, and many became bankrupt.

The magnitude of the works, which were unprecedented in England, was one of the most remarkable features in the undertaking. The following striking comparison has been made between this railway and one of the greatest works of ancient times. The Great Pyramid of Egypt was, according to Diodorus Siculus, constructed by 300,000—according to Herodotus, by 100,000—men. It required for its execution twenty years, and the labour expended upon it has been estimated as equivalent to lifting 15,733,000,000 of cubic feet of stone one foot high. Whereas, if the labour expended in constructing the London and Birmingham Railway be in like manner reduced to one common denomination the result is 25,000,000,000 of cubic feet more than was lifted for the Great Pyramid; and yet the English work was performed by about 20,000 men in less than five years. And whilst the Egyptian work was executed by a powerful monarch concentrating upon it the labour and capital of a great nation, the English railway was constructed, in the face of every conceivable obstruction and difficulty, by a company of private individuals out of their own resources, without the aid of Government or the contribution of one farthing of public money.

The labourers who executed this formidable work were in many respects a remarkable class. The “railway navvies,” as they are called, were men drawn by the attraction of good wages from all parts of the kingdom; and they were ready for any sort of hard work. Some of the best came from the fen districts of Lincoln and Cambridge, where they had been trained to execute works of excavation and embankment. These old practitioners formed a nucleus of skilled manipulation and aptitude, which rendered them of indispensable utility in the immense undertakings of the period. Their expertness in all sorts of earthworks, in embanking, boring, and well-sinking—their practical knowledge of the nature of soils and rocks, the tenacity of clays, and the porosity of certain stratifications—were very great; and, rough-looking though they were, many of them were as important in their own department as the contractor or the engineer.

During the railway-making period the navvy wandered about from one public work to another—apparently belonging to no country and having no home. He usually wore a white felt hat with the brim turned up, a velveteen or jean square-tailed coat, a scarlet plush waistcoat with little black spots, and a bright-coloured kerchief round his herculean neck, when, as often happened, it was not left entirely bare. His corduroy breeches were retained in position by a leathern strap round the waist, and were tied and buttoned at the knee, displaying beneath a solid calf and foot encased in strong high-laced boots. Joining together in a “butty gang,” some ten or twelve of these men would take a contract to cut out and remove so much “dirt”—as they denominated earth-cutting—fixing their price according to the character of the “stuff,” and the distance to which it had to be wheeled and tipped. The contract taken, every man put himself on his mettle; if any was found skulking, or not putting forth his full working power, he was ejected from the gang. Their powers of endurance were extraordinary. In times of emergency they would work for 12 and even 16 hours, with only short intervals for meals. The quantity of flesh-meat which they consumed was something enormous; but it was to their bones and muscles what coke is to the locomotive—the means of keeping up the steam. They displayed great pluck, and seemed to disregard peril. Indeed the most dangerous sort of labour—such as working horse-barrow runs, in which accidents are of constant occurrence—has always been most in request amongst them, the danger seeming to be one of its chief recommendations.

Working, eating, drinking, and sleeping together, and daily exposed to the same influences, these railway labourers soon presented a distinct and well-defined character, strongly marking them from the population of the districts in which they laboured. Reckless alike of their lives as of their earnings, the navvies worked hard and lived hard. For their lodging, a hut of turf would content them; and, in their hours of leisure, the meanest public-house would serve for their parlour. Unburdened, as they usually were, by domestic ties, unsoftened by family affection, and without much moral or religious training, the navvies came to be distinguished by a sort of savage manners, which contrasted strangely with those of the surrounding population. Yet, ignorant and violent though they might be, they were usually good-hearted fellows in the main—frank and openhanded with their comrades, and ready to share their last penny with those in distress. Their pay-nights were often a saturnalia of riot and disorder, dreaded by the inhabitants of the villages along the line of works. The irruption of such men into the quiet hamlet of Kilsby must, indeed, have produced a very startling effect on the recluse inhabitants of the place. Robert Stephenson used to tell a story of the clergyman of the parish waiting upon the foreman of one of the gangs to expostulate with him as to the shocking impropriety of his men working during Sunday. But the head navvy merely hitched up his trousers, and said, 'Why, Soondays hain’t cropt out here yet!' In short, the navvies were little better than heathens, and the village of Kilsby was not restored to its wonted quiet until the tunnel-works were finished, and the engines and scaffoldings removed, leaving only the immense masses of débris around the line of shafts which extend along the top of the tunnel.

In illustration of the extraordinary working energy and powers of endurance of the English navvies, we may mention that when railway-making extended to France, the English contractors for the works took with them gangs of English navvies, with the usual plant, which included wheelbarrows. These the English navvy was accustomed to run out rapidly and continuously, piled so high with “stuff” that he could barely see over the summit of his load, the gang-board along which he wheeled his barrow. While he thus easily ran out some 3 or 4 cwt. at a time, the French navvy was contented with half the weight. Indeed, the French navvies on one occasion struck work because of the size of the English barrows, and there was an émeute on the Rouen Railway, which was only quelled by the aid of the military. The consequence was that the big barrows were abandoned to the English workmen, who earned nearly double the wages of the Frenchmen. The manner in which they stood to their work was matter of great surprise and wonderment to the French people, who came crowding round them in their blouses, and, after gazing admiringly at their expert handling of the pick and mattock, and the immense loads of “dirt” which they wheeled out, would exclaim to each other, 'Mon Dieu, voila! voila ces Anglais, comme ils travaillent!'.