ABSTRACT
A quick and safe means of communication beneath the overcrowded streets of London has always been the great ideal of modern engineers. The public, however, have, perhaps not unnaturally, regarded the scheme as little less than Utopian, and one which, even if it could be accomplished, would certainly never pay. A subterranean railway under London was awfully suggestive of dark, noisome tunnels, buried many fathoms deep beyond the reach of light or life; passages inhabited by rats, soaked with sewer drippings, and poisoned by the escape of gas mains. It seemed an insult to common sense to suppose that people who could travel as cheaply to the city on the outside of a Paddington ’bus would ever prefer, as a merely quicker medium, to be driven amid palpable darkness through the foul subsoil of London. The pertinacity, too, with which the scheme at first hung fire strengthened not a little the incredulity of those who from the beginning had dis-believed it altogether. The Subterranean Railway has been talked about for years, and nothing done, till the whole idea has been gradually associated with the plans for flying machines, warfare by balloons, tunnels under the Channel, and other bold but somewhat hazardous propositions of the same kind. Yet many enterprising men have always adhered to the Subterranean Railway, have advocated its feasibility, and supported its use, till they at last brought about a result even more difficult to accomplish, if possible, than that of constructing the line itself—they got the capital for it. With the money for the undertaking, and with Mr. John Fowler as engineer, the rest has been comparatively easy. Working quietly under ground, only stopping up a thoroughfare now and then, or making an awful crack here and there in the walls of some houses under which it passed, the line has been slowly but very surely progressing from west to east, till the greater part of it is now far advanced towards completion, and the first length will actually be opened for public traffic, from the Victoria-street Station to Paddington, before the 1st of next May—the date by which it is, of course, sought to complete all our improvements in the means of metropolitan communication. When it is opened, we venture to think the public will be agreeably surprised to find that this underground railway is for nearly half its length not underground at all, and that where it does pass for various lengths beneath the streets, the tunnels, instead of being close, dark, damp, and ill-smelling passages, are wide, spacious, clean, and excellently well lit, reminding one, in fact, more of a well-kept street by night than a subterranean passage through the very heart of this dense metropolis. Whether the railway is one which will or will not remunerate the shareholders we venture no opinion, but both as one of the most novel and important works of the kind that have yet entered the city, and as one which, we think, must prove of the greatest convenience to the public, it deserves full notice in our columns. The present powers of the company only allow them to carry their line from Paddington to Finsbury-circus, a distance of four and a half miles, and of this length, as we have said, more than three miles, from Paddington to the Victoria-street Station, are in many parts quite complete, and in others nearly so, with perfect working junctions with the Great Western and Northern Railways. It commences at the Paddington Station, and is continued thence, in an almost direct line, towards the New-road, passing beneath the Edgware-road at right angles, and intersecting in the same manner Lisson-grove-road and Upper Baker-street, skirting along, beneath, and just outside the southern extremity of Regent’s Park. Thence it passes under the houses at the eastern extremity of Park-crescent (some three or four houses in which have been by no means improved by its passage), continues beneath Tottenham-court-road into the New-road, and, passing close by Euston-square, turns at King’s-cross to effect a junction with the up and down lines of the Great Northern Railway. From King’s-cross a great part of the line is an open cutting, except for a length of about 600 yards beneath Bagnigge-wells-road and Coppice-row, where again, for the length we have said, a tunnel intervenes. From this to the Victoria-street Station it is nearly all a fair open cutting, and up to this point the line is nearly ready. From the Victoria-street Station, to be erected on the dirty waste ground, beyond Holborn, which is now dignified with the name of Victoria-street, the line is soon to have two branches, one intersecting Holborn-hill, or rather Skinner-street, and, continuing its course due south under the site of the old Fleet Prison, effecting a junction with the Chatham and Dover line, which is to cross the Thames at Blackfriars. The other and more important branch—in fact, the main line—is to be continued under the ground north of Smithfield and south of Charterhouse-square, and will pass beneath Barbican into Finsbury-circus. At this terminus it is intended, for the present at least, to stop; though there is not the least doubt but, as the advantages which this quick mode of communication will afford and the relief which it must give to the enormously overcrowded traffic of our streets become more generally known and appreciated, the shareholders themselves will find their own account in extending their branches to all the chief suburban districts of the metropolis. As it is, even completed to the Victoria-street Station, and communicating with the Chatham and Dover-bridge when finished, the facilities which it will offer to rapid travelling will be immense. A person starting from Brighton or Dover will be put down almost at his own door at Bayswater, instead of, as now, taking almost as much time to travel from London-bridge to Bayswater as to perform a long journey by rail. In like manner, those coming from the North—from Edinburgh, Liverpool, or Manchester—will be able to book direct through to Dover or Southampton without the loss of a minute on their journey. It is not too much to say that for passengers pressed for time the two or three miles interval between the northern and southern stations of the metropolis are equal in actual delay to 200 or 300 miles distance on an unbroken journey. But though most of our readers know the fact of the delay, many of them may ask, why was it necessary to take the line underground? To this we can only reply, in the words of the company, that it was not necessary at all, but that as by so doing they could effect a very great saving in the cost of the undertaking, it was thought to be most desirable. Sewers were not to be interfered with, gas-pipes were to be regarded as sacred, water-pipes not to be touched, churches to be avoided, and houses to be left secure. With these trifling drawbacks, Mr. Fowler was at liberty to take his tunnel through a labyrinth of sewers and gas and water mains if he could. At every step vestries, gas and water companies, and the Board of Works had to be consulted, and but for the kind and liberal spirit in which the company was met, and the fair efforts which were everywhere made by these bodies to help them over their great difficulties, the railway could never have been made at all. Perhaps, however, a short rough outline of the portion of the line now nearly completed will give our readers the best idea of what these difficulties were. To the Victoria-street Station the line is nearly 3½ miles long, having stations at Paddington, Edgware-road, Baker-street, Portland-road, Euston-square, King’s-cross, and Victoria-street. From west to east the average slope downwards of the whole line is about 1 in 300 feet, though after entering the city it again rises, but there is no steeper gradient throughout than 1 in 100. Its greatest curve is of 200 yards radius, and its greatest depth from the ground above to the rails not less than 54 feet, and there are not more than 1,200 yards of straight line throughout. The span of the arch of the tunnel is 28½ feet, its form is elliptical, and its height 17 feet, except in the parts where there is great superincumbent pressure, when the form of the arch is altered to give it greater strength and to take the crown to a height of 19 feet. The foundations of the tunnel go from four to five feet into the solid ground on each side below the rails, except in some few places, where the close vicinity of very heavy buildings rendered extra strength necessary, and here the tunnel has been driven like a shaft, and is a solid ring of massive brickwork above and below; in fact, in all parts of the tunnel itself the most zealous care has been taken to insure the structure being everywhere greatly in excess of the strength it actually requires. Thus, even the lightest parts of the tunnel have six rings of brickwork, though railway arches of seven feet greater span are never built with more than five. The outer sides of the arches also are filled in with solid beds of concrete, and the whole covered over with a layer of asphalte to keep it water-tight. In fact, the tunnel has been formed on what engineers call the “cut and cover” principle; that is, the ground has been opened to the base of the intended tunnel, the tunnel built, covered with concrete, and asphalte and filled in again with earth and the roadway paved over as before. On this plan and working in 12ft. lengths the tunnel has actually been constructed at the rate of 72ft. a week, quicker than any work of the kind has ever yet been accomplished. It has not all, however, been knocked off at this rapid rate. Passing near churches and heavy buildings the tunnel has been regularly driven in four-feet lengths by skilled miners; and such portions, being conducted with the most zealous care, have advanced but slowly. At the western extremity, where the soil was a fine gravel, the works were at one time greatly impeded by the water, which in that district is abundant everywhere at about 14ft. from the surface. This it was useless to try pumping out, as the pumps brought up sand and gravel as well as water, and would, had the attempt been persevered in, have brought up the very foundation of the surrounding houses also. It was necessary at last to make regular drains into the low-level sewers in order to keep the works free. Through the gravel and through the London clay the labour has been very easy, but in parts where there was light, loose, sandy soil a great deal of difficulty was experienced. All the really difficult parts have now, however, been surmounted, and the tunnel built in the most solid manner. The lines of rails are laid through many lengths, each line being double gauge, intended for both the broad and narrow traffic. Where the junctions have been effected at Paddington and King’s-cross it was necessary at the point where the switch rails joined to widen the tunnel, and at these parts make it, in fact, like the mouth of a trumpet. This was the most difficult operation ever attempted in either tunnelling or brickwork, but Mr. Fowler has surmounted all the obstacles in a masterly manner. What made the work at King’s-cross more difficult than all was that at precisely the most difficult part of all the junctions the great Fleet Ditch sewer crossed it right through the crown of the tunnel arch. As the sewer, of course, could not be disturbed, the obstacle was met by carrying it across, slung, as it were, in a powerful cast-iron trough, and there it now hangs, peering through the brickwork like a colossal main, and with all beneath it as dry and sweet-smelling as if Fleet Ditch—that fullest and foulest of all London’s sewers—were 100 miles away. It is but justice to Mr. Jay, the contractor, for all this end of the works from Euston-square to say that he has accomplished all the designs in the most massive and careful manner, and that, in fact, the works here are regarded among engineers as positive models of what contract labour should be. The stations along the line which we have already enumerated will, all but two, be open-air stations, and even those that are to be underground will be amply lit by daylight coming through apertures in the roof of the arch. But one of the greatest difficul-ties of all the many that had to be overcome consisted in constructing an engine that should be at once of great power and speed, capable of consuming its own smoke, and, above all, to give off no steam. Ordinary engines passing through tunnels so completely enclosed would in a very short time fill them with such a mixture of steam and smoke as would be very nearly suffocating, would make signals almost useless, and, in short, render the traffic not only disagreeable but dangerous. To avoid all these complicated evils Mr. Fowler has invented an engine which, while in the open air, works like a common locomotive, but, when in the tunnel, consumes its own smoke, or rather makes none, and by condensing its own steam gives off not a particle of vapour.
