Lives of the Engineers - Part 16
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Part 16

Similar opposition was offered at many other points, but ineffectually.

The laborious application of Robert Stephenson was such, that in examining the country to ascertain the best line, he walked the whole distance between London and Birmingham upwards of twenty times.

When the bill went before the Committee of the Commons in 1832, a formidable array of evidence was produced. All the railway experience of the day was brought to bear in support of the measure, and all that interested opposition could do was set in motion against it. The necessity for an improved mode of communication between London and Birmingham was clearly demonstrated; and the engineering evidence was regarded as quite satisfactory. Not a single fact was proved against the utility of the measure, and the bill pa.s.sed the Committee, and afterwards the third reading in the Commons, by large majorities.

It was then sent to the Lords, and went into Committee, when a similar ma.s.s of testimony was again gone through. But it had been evident, from the opening of the proceedings, that the fate of the bill had been determined before even a word of the evidence had been heard. At that time the committees were open to all peers; and the promoters of the bill found, to their dismay, many of the lords who were avowed opponents of the measure as landowners, sitting as judges to decide its fate. Their princ.i.p.al object seemed to be, to bring the proceedings to a termination as quickly as possible. An attempt at negotiation was indeed made in the course of the proceedings in committee, but failed, and the bill was thrown out.

As the result had been foreseen, measures were taken to neutralise the effect of this decision as regarded future operations. Not less than 32,000 had been expended in preliminary and parliamentary expenses up to this stage; but the promoters determined not to look back, and forthwith made arrangements for prosecuting the bill in the next session. Strange to say, the bill then pa.s.sed both Houses silently and almost without opposition. The mystery was afterwards solved by the appearance of a circular issued by the directors of the company, in which it was stated, that they had opened "negotiations" with the most influential of their opponents; that "these measures had been successful to a greater extent than they had ventured to antic.i.p.ate; and the most active and formidable had been conciliated." An instructive commentary on the mode by which these n.o.ble lords and influential landed proprietors had been "conciliated," was the simple fact that the estimate for land was nearly trebled, and that the owners were paid about 750,000 for what had been originally estimated at 250,000.

The landowners having thus been "conciliated," the promoters of the measure were permitted to proceed with the formation of their great highway. Robert Stephenson was, with the sanction of his father, appointed sole engineer; and steps were at once taken by him to make the working survey, to prepare the working drawings, and arrange for the construction of the railway. Eighty miles of the road were shortly under contract, having been let within the estimates; and the works were in satisfactory progress by the beginning of 1834.

The difficulties encountered in their construction were very great; the most formidable of them originating in the character of the works themselves. Extensive tunnels had to be driven through unknown strata, and miles of underground excavation had to be carried out in order to form a level road from valley to valley, under the intervening ridges.

This kind of work was the newest of all to the contractors of that day.

Robert Stephenson's experience in the collieries of the North rendered him well fitted to grapple with such difficulties; yet even he, with all his practical knowledge, could scarcely have foreseen the serious obstacles which he was called upon to encounter in executing the formidable cuttings, embankments, and tunnels of the London and Birmingham Railway. It would be an uninteresting, as it would be a fruitless task, to attempt to describe the works in detail; but a general outline of their extraordinary character and extent may not be out of place.

[Picture: Rugby to Watford]

The length of railway to be constructed between London and Birmingham was 112 miles. The line crossed a series of low-lying districts separated from each other by considerable ridges of hills; and it was the object of the engineer to cross the valleys at as high, and the hills at as low, elevations as possible. The high ground was therefore cut down and the "stuff" led into embankments, in some places of great height and extent, so as to form a road upon as level a plane as was considered practicable for the working of the locomotive engine. In some places, the high grounds were pa.s.sed in open cuttings, whilst in others it was necessary to bore through them in tunnels with deep cuttings at each end.

The most formidable excavations on the line are those at Tring, Denbigh Hall, and Blisworth. The Tring cutting is an immense chasm across the great chalk ridge of Ivinghoe. It is 2 miles long, and for of a mile is 57 feet deep. A million and a half cubic yards of chalk and earth were taken out of this cutting by means of horse-runs and deposited in spoil banks; besides the immense quant.i.ty run into the embankment north of the cutting, forming a solid mound nearly 6 miles long and about 30 feet high. Pa.s.sing over the Denbigh Hall cutting, and the Wolverton embankment of 1 mile in length across the valley of the Ouse, we come to the excavation at Blisworth, a brief description of which will give the reader an idea of one of the most difficult kinds of railway work.

[Picture: Blisworth Cutting]

The Blisworth Cutting is one of the longest and deepest grooves cut in the solid earth. It is 1 mile long, in some places 65 feet deep, pa.s.sing through earth, stiff clay, and hard rock. Not less than a million cubic yards of these materials were dug, quarried, and blasted out of it. One-third of the cutting was stone, and beneath the stone lay a thick bed of clay, under which were found beds of loose shale so full of water that almost constant pumping was necessary at many points to enable the works to proceed. For a year and a half the contractor went on fruitlessly contending with these difficulties, and at length he was compelled to abandon the adventure. The engineer then took the works in hand for the Company, and they were vigorously proceeded with.

Steam-engines were set to work to pump out the water; two locomotives were put on, one at each end of the cutting, to drag away the excavated rock and clay; and 800 men and boys were employed along the work, in digging, wheeling, and blasting, besides a large number of horses. Some idea of the extent of the blasting operations may be formed from the fact that 25 barrels of gunpowder were used weekly; the total quant.i.ty exploded in forming this one cutting being about 3,000 barrels.

Considerable difficulty was experienced in supporting the bed of rock cut through, which overlaid the clay and shale along each side of the cutting. It was found necessary to hold it up by strong retaining walls, to prevent the clay bed from bulging out, and these walls were further supported by a strong invert,-that is, an arch placed in an inverted position under the road,-thus binding together the walls on both sides.

Behind the retaining walls, a drift or horizontal drain was provided to enable the water to run off, and occasional openings were left in the walls themselves for the same purpose. The work was at length brought to a successful completion, but the extraordinary difficulties encountered in forming the cutting had the effect of greatly increasing the cost of this portion of the railway.

The Tunnels on the line are eight in number, their total length being 7336 yards. The first high ground encountered was Primrose Hill, where the stiff London clay was pa.s.sed through for a distance of about 1164 yards. The clay was close, compact, and dry, more difficult to work than stone itself. It was entirely free from water; but the absorbing properties of the clay were such that when exposed to the air it swelled out rapidly. Hence an unusual thickness of brick lining was found necessary; and the engineer afterwards informed the author that for some time he entertained an apprehension lest the pressure should force in the brickwork altogether. It was so great that it made the face of the bricks to fly off in minute chips which covered his clothes whilst he was inspecting the work. The materials used in the building were, however, of excellent quality; and the tunnel was happily brought to a completion without any accident.

At Watford the chalk ridge was penetrated by a tunnel about 1800 yards long; and at Northchurch, Lindslade, and Stowe Hill, there were other tunnels of minor extent. But the chief difficulty of the undertaking was the execution of that under the Kilsby ridge. 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.

[Picture: The Shafts over Kilsby Tunnel]

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 p.r.o.nounced 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 a.s.sistants, and the workmen were cl.u.s.tered 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 ma.s.s of sand, which had completely choked up the pa.s.sage, 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 quant.i.ty 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 coa.r.s.eness 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 s.p.a.ce 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, ere 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 quant.i.ty 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 burthen. 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 circ.u.mstance that notwithstanding the quant.i.ty thus removed, the level of the surface of the water in the tunnel was only lowered about 2 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 pa.s.sed.

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 a.s.sistance 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 cla.s.s. 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 pract.i.tioners formed a nucleus of skilled manipulation and apt.i.tude, which rendered them of indispensable utility in the immense undertakings of the period.

Their expertness in all sorts of earthwork, 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 b.u.t.toned at the knee, displaying beneath a solid calf and foot encased in strong high-laced boots. Joining together in a "b.u.t.ty 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 quant.i.ty of flesh-meat which they consumed was something enormous; but it was to their bones and muscles what c.o.ke 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 ma.s.ses of _debris_ around the line of shafts which extend along the top of the tunnel.

In ill.u.s.tration 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 _emeute_ 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 countrypeople, 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_!"

CHAPTER XIV.

MANCHESTER AND LEEDS, AND MIDLAND RAILWAYS-STEPHENSON'S LIFE AT ALTON-VISIT TO BELGIUM-GENERAL EXTENSION OF RAILWAYS AND THEIR RESULTS.

The rapidity with which railways were carried out, when the spirit of the country became roused, was indeed remarkable. This was doubtless in some measure owing to the increased force of the current of speculation at the time, but chiefly to the desire which the public began to entertain for the general extension of the system. It was even proposed to fill up the ca.n.a.ls, and convert them into railways. The new roads became the topic of conversation in all circles; they were felt to give a new value to time; their vast capabilities for "business" peculiarly recommended them to the trading cla.s.ses; whilst the friends of "progress" dilated on the great benefits they would eventually confer upon mankind at large. It began to be seen that Edward Pease had not been exaggerating when he said, "Let the country but make the railroads, and the railroads will make the country!" They also came to be regarded as inviting objects of investment to the thrifty, and a safe outlet for the acc.u.mulations of inert men of capital. Thus new avenues of iron road were soon in course of formation, branching in all directions, so that the country promised in a wonderfully short time to become wrapped in one vast network of iron.

In 1836 the Grand Junction Railway was under construction between Warrington and Birmingham-the northern part by Mr. Stephenson, and the southern by Mr. Rastrick. The works on that line embraced heavy cuttings, long embankments, and numerous viaducts; but none of these are worthy of any special description. Perhaps the finest piece of masonry on the railway is the Dutton Viaduct across the valley of the Weaver. It consists of twenty arches of 60 feet span, springing 16 feet from the perpendicular shaft of each pier, and 60 feet in height from the crown of the arches to the level of the river. The foundations of the piers were built on piles driven 20 feet deep. The structure has a solid and majestic appearance, and is perhaps the finest of George Stephenson's viaducts.

[Picture: The Dutton Viaduct]

The Manchester and Leeds line was in progress at the same time-an important railway connecting the princ.i.p.al manufacturing towns of Yorkshire and Lancashire. An attempt was made to obtain the Act as early as 1831; but its promoters were defeated by the powerful opposition of the landowners aided by the ca.n.a.l companies, and the project was not revived for several years. The line was somewhat circuitous, and the works were heavy; but on the whole the gradients were favourable, and it had the advantage of pa.s.sing through a district full of manufacturing towns and villages, teeming hives of population, industry, and enterprise. The Act authorising the construction of the railway was obtained in 1836; it was greatly amended in the succeeding year, and the first ground was broken on the 18th August, 1837.

In conducting this project to an issue, the engineer had the usual opposition and prejudices to encounter. Predictions were confidently made in many quarters that the line could never succeed. It was declared that the utmost engineering skill could not construct a railway through such a country of hills and hard rocks; and it was maintained that, even if the railroad were practicable, it could only be made at a ruinous cost.

During the progress of the works, as the Summit Tunnel, near Littleborough, was approaching completion, the rumour was spread abroad in Manchester that the tunnel had fallen in and buried a number of the workmen. The last arch had been keyed in, and the work was all but finished, when the accident occurred which was thus exaggerated by the lying tongue of rumour. An invert had given way through the irregular pressure of the surrounding earth and rock at a part of the tunnel where a "fault" had occurred in the strata. A party of the directors accompanied the engineer to inspect the scene of the accident. They entered the tunnel's mouth preceded by upwards of fifty navvies, each bearing a torch.

After walking a distance of about half a mile, the inspecting party arrived at the scene of the "frightful accident," about which so much alarm had been spread. All that was visible was a certain unevenness of the ground, which had been forced up by the invert under it giving way; thus the ballast had been loosened, the drain running along the centre of the road had been displaced, and small pools of water stood about. But the whole of the walls and the roof were still as perfect as at any other part of the tunnel.

[Picture: Entrance to the Summit Tunnel, Littleborough]

The engineer explained the cause of the accident; the blue shale, he said, through which the excavation pa.s.sed at that point, was considered so hard and firm, as to render it unnecessary to build the invert very strong there. But shale is always a deceptive material. Subjected to the influence of the atmosphere, it gives but a treacherous support. In this case, falling away like quicklime, it had left the lip of the invert alone to support the pressure of the arch above, and hence its springing inwards and upwards. Mr. Stephenson directed the attention of the visitors to the completeness of the arch overhead, where not the slightest fracture or yielding could be detected. Speaking of the work, in the course of the same day, he said, "I will stake my character and my head, if that tunnel ever give way, so as to cause danger to any of the public pa.s.sing through it. Taking it as a whole, I don't think there is such another piece of work in the world. It is the greatest work that has yet been done of this kind, and there has been less repairing than is usual,-though an engineer might well be beaten in his calculations, for he cannot beforehand see into those little fractured parts of the earth he may meet with." As Stephenson had promised, the invert was put in; and the tunnel was made perfectly safe.

The construction of this subterranean road employed the labour of above a thousand men for nearly four years. Besides excavating the arch out of a solid rock, they used 23,000,000 of bricks, and 8000 tons of Roman cement in the building of the tunnel. Thirteen stationary engines, and about 100 horses, were also employed in drawing the earth and stone out of the shafts. Its entire length is 2869 yards, or nearly 1 mile-exceeding the famous Kilsby Tunnel by 471 yards.

The Midland Railway was a favourite line of Mr. Stephenson's for several reasons. It pa.s.sed through a rich mining district, in which it opened up many valuable coalfields, and it formed part of the great main line of communication between London and Edinburgh. The Act was obtained in 1836, and the first ground was broken in February, 1837.

Although the Midland Railway was only one of the many great works of the same kind executed at that time, it was almost enough of itself to be the achievement of a life. Compare it, for example with Napoleon's military road over the Simplon, and it will at once be seen how greatly it excels that work, not only in the constructive skill displayed in it, but also in its cost and magnitude, and the amount of labour employed in its formation. The road of the Simplon is 45 miles in length; the North Midland Railway is 72 miles. The former has 50 bridges and 5 tunnels, measuring together 1338 feet in length; the latter has 200 bridges and 7 tunnels, measuring together 11,400 feet, or about 2 miles. The former cost about 720,000 sterling, the latter above 3,000,000. Napoleon's grand military road was constructed in six years, at the public cost of the two great kingdoms of France and Italy; while Stephenson's railway was formed in about three years, by a company of private merchants and capitalists out of their own funds, and under their own superintendence.

It is scarcely necessary that we should give any account in detail of the North Midland works. The making of one tunnel so much resembles the making of another,-the building of bridges and viaducts, no matter how extensive, so much resembles the building of others,-the cutting out of "dirt," the blasting of rocks, and the wheeling of excavation into embankments, is so much a matter of mere time and hard work,-that is quite unnecessary for us to detain the reader by any attempt at their description. Of course there were the usual difficulties to encounter and overcome,-but the railway engineer regarded these as mere matters of course, and would probably have been disappointed if they had not presented themselves.

On the Midland, as on other lines, water was the great enemy to be fought against,-water in the Claycross and other tunnels,-water in the boggy or sandy foundations of bridges,-and water in cuttings and embankments. As an ill.u.s.tration of the difficulties of bridge building, we may mention the case of the five-arch bridge over the Derwent, where it took two years' work, night and day, to get in the foundations of the piers alone.

Another curious ill.u.s.tration of the mischief done by water in cuttings may be briefly mentioned. At a part of the North Midland Line, near Ambergate, it was necessary to pa.s.s along a hillside in a cutting a few yards deep. As the cutting proceeded, a seam of shale was cut across, lying at an inclination of 6 to 1; and shortly after, the water getting behind the bed of shale, the whole ma.s.s of earth along the hill above began to move down across the line of excavation. The accident completely upset the estimates of the contractor, who, instead of 50,000 cubic yards, found that he had about 500,000 to remove; the execution of this part of the railway occupying fifteen months instead of two.