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"The question then arose, whether, in the face of this tremendous difficulty, the execution of the Kilsby Tunnel should be continued or abandoned. The general opinion of the several eminent engineers who were consulted was against proceeding, and certainly the amount of the difficulties which were subsequently incurred justified the verdict. But in science, as well as in war, the word 'iMpossibW can occasionally, by cool and extraordinary exertions, be divested of its first syllable; and, accordingly, Mr. Robert Stephenson offering, after mature reflection, to undertake the responsibility of proceeding, he was duly authorised to do so.
"His first operation was of course to endeavour by the power of steam-engines—the comrades of his life—to lower the water with which he had to contend; and although, to a certain degree, this attempt succeeded, yet by the draining of remote springs, and by the sinking of the water in wells at considerable distances, it was soon ascertained that the quicksand in question covered several square miles.
"The tunnel, thirty feet high by thirty feet broad, arched at the top as well as the bottom, was formed of bricks laid in cement, and the bricklayers were progressing in "lengths' averaging twelve feet, when those who were nearest the quicksand, on driving into the roof, were suddenly almost overwhelmed by a deluge of water which burst in upon them. As it was evident that no time was to be lost, a gang of workmen, protected by the extreme power of the engines, were, with their materials, placed on a raft; and while, with the utmost celerity, they were completing the walls of that short length, the water, in spite of every effort to keep it down, rose with such rapidity that, at the conclusion of the work, the men were so near being jammed against the roof, that the assistant engineer, Mr. Charles Lean, in charge of the party, jumped overboard, and then, swimming with a rope in his mouth, he towed the raft to the foot of the nearest working
Chap. xxv.J THE KIL8BY TUNNEL. 335
shaft, through which he and his men were safely lifted up into daylight, or, as it is termed by miners,' to grass?
"The water now rose in the shaft, and, as it is called, 'drowned out' the works. For a considerable time all the pumping apparatus appeared to be insufficient. Indeed, the effort threatened to be so hopeless, that the directors of the company almost determined to abandon it; but the engineerin-chief, relying on the power of his engines, prayed for one fortnight more. Before that period expired, science triumphed over her subterranean foe, and—thanks to the inventors of the steam-engine—the water gradually lowered.
"By the main strength of 1250 men, 200 horses, and thirteen steam-engines, not only was the work gradually completed, but during night and day, for eight months, the astonishing and almost incredible quantity of 1600 gallons per minute from the quicksand alone was raised by Mr. Robert Stephenson, and conducted away I
"The time occupied, from the laying of the first brick to the completion of the work, was thirty months. The number of bricks used was 36,000,000 — sufficient to make a good footpath from London to Aberdeen (missing the Forth) a yard broad!"
The cost of executing the Kilsby Tunnel was, in consequence of these formidable and unforeseen difficulties, increased from 90,0007. (the amount of the original estimate) to about 350,000/. Enormous sums were paid for land and compensation—far beyond the amounts originally estimated. Thus 3,000/. were given for one piece of land, and 10,000/. for consequential damages, when it was afterwards made clear that the land had been greatly improved in value by the formation of the railway. After compensation had been paid for land alleged to have been thus deteriorated, the Company, on purchasing any further quantity, had almost invariably to pay a higher price, on the ground of its increased value! All sorts of payments were demanded on the most frivolous pretexts. The landowners discovered that they could demand accommodation bridges, which they did in large numbers. One originally demanded five, but afterwards came down to four, with an equivalent in the price of the bridge given up. Then he found he could do with three bridges, provided the Company would pay him a further sum in hard cash, which they were ready to do; and, in like manner, he gave up the remaining bridges, on being paid a furti.er round s'm: in fact, the bridges were wholly unnecessary, and had only been insisted on as a means of extorting money from the Company. To these causes of increased expense must be added the rise in the prices of labour and materials which took place shortly after the letting of the works, by which many of the contractors were ruined, no fewer than seven of the contracts having thus been thrown upon the Company's hands. The directors had then to purchase all kinds of implements and materials at great expense, in order to carry on the works and avoid heavier loss. But the energy of the engineers, cordially supported by the directory and proprietors, enabled them at length, after many years' anxiety, to bring the stupendous undertaking to a successful completion, though at a cost far beyond that which had been originally estimated.
The estimates laid by Mr. Robert Stephenson before Parliament amounted to 2,750,000/.; and it was then confidently expected that the works would have been completed within this sum. The most eminent engineers of the day were brought forward to give evidence on the subject, and those of the greatest experience stated their opinion to be that the estimates were altogether too high. Mr. Walker said the prices allowed were 30 per cent, higher than any he could remember. Mr. Locke considered them too high; and Mr. Rastrick objected to support the estimates for the same reason. Yet the result proved them to have been
Chap, xxv.] COST OF THE WORKS. 337
much too low. The works were, it is true, let to the contractors under the sum estimated, but in consequence of the adverse circumstances which occurred in the course of their execution, the expenditure had reached the immense amount of 5,000,000/., or about double the original estimate, before the line was opened for public traffic.
Strong animadversions were made at the time upon this excessive expenditure; but the circumstances which we have stated,— the obstacles encountered in the Kilsby and other tunnels, the rapid rise in the price of labour and materials, the extortions of the landowners (which it was impossible accurately to estimate), were sufficient in a considerable degree to account for the excess: in addition to which, it was a matter of the greatest difficulty for men of the very highest talent and experience then to form accurate estimates of the labour attending works of so stupendous a character, in the absence of the data since furnished by experience. Mr. Robert Stephenson, in his evidence before a committee of the House of Commons in 1839, gave this further explanation : —" The principal excess, or at least a very large item of the excess, arose from the stations on the line. The public required much larger accommodation at the stations than was originally contemplated. In fact, at the time the estimate of the London and Birmingham Railway was made, it was apprehended that something like 25,000/. or 30,000/. for a station at each end of the line was ample; but they have exceeded 100,000/. I have no hesitation in saying that the expense of stations has been eight or ten-fold beyond the parliamentary estimate. The plans were on much too small a scale in the stations originally contemplated." "But," he remarked on another occasion *, "let individuals who make observations as to the excessive cost of the works as compared with the estimates, look not at the commencement but at their close. Let them recollect that those great works now spreading irresistibly like network all over the country, are exciting commercial enterprise, augmenting the national wealth, increasing our social comforts, and raising the nation in the scale of civilisation. It is the end, therefore, that ought to be looked at, and not the beginning; and you, contractors, have all contributed your mite, as well as myself, to produce those glorious results."
* Speech of Mr. Robert Stephenson at the dinner given to him by the contractors for the London and Birmingham Railway, on the occasion of presenting him with a testimonial November 16th, 1839.
It is probable, indeed, that had the projectors of the undertaking foreseen that it would cost as much as five millions sterling, they would have been deterred from entering upon it. As it was, however, the expenditure, though immense, was justified by the result; for the excess in the traffic beyond the estimates was even greater in proportion than the excess in the capital expenditure. The line of 112 miles in length was opened on the 17th of September, 1838, and in the following year the receipts from passenger traffic alone amounted to 608,564/. The company was enabled to pay its proprietors a large dividend; and the results of the working were cited as sufficient grounds for pushing railways in all directions.
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 three hundred thousand — according to Herodotus, by one hundred thousand —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 in the same manner the labour expended in constructing