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, 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 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 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 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 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.