Once a Week (magazine)/Series 1/Volume 1/New Westminster Bridge
NEW WESTMINSTER BRIDGE.
General literature takes little notice of parliamentary blue-books, and an extract from one of these somewhat heavy volumes is scarcely a dainty dish to set before a reader; let us, however, draw attention to the following exceedingly brief announcement copied from a blue-book on Westminster Bridge:
In 1853 an Act was passed enabling the commissioners of her Majesty’s works and public buildings to remove the present bridge, and to build a new bridge on or near the site thereof.
The contract for the execution of the works was entered into with Messrs. Mare and Co., April, 1854, and they were shortly afterwards commenced.
In September, 1855, Messrs Mare became bankrupts, and the works were carried on by the assignees until the end of March, 1856, when they were entirely suspended. In the same year communications were entered into with the Messrs. Cochrane, which ended in their taking up the contract, the final arrangements between the firm and the commissioners being completed, and the work recommenced on the 1st September, 1858.
Such is a rapid resume of the past history of the new bridge, uninteresting enough to unprofessional readers, and so with them we willingly turn to a nearer view of the work itself, as it is now being carried out, and endeavour to gain some slight insight into the philosophy of bridge-building. In this enlightened age, which ill natured folk call “sciolistic,” and hopeful people “progressive;” when amateurs abound, and we often see not only “every man his own doctor” (thanks to the efforts of homœopaths, and their portable medicine-chests), but sometimes too every man his own architect, lawyer—nay, even parson, it is curious to remark how, with all this stripping off of old prejudices—this “admission free” into Eleusinian mysteries, there remains one profession which is yet a terra incognita to the general public, one branch of work-a-day knowledge whose technical terms even, to say nothing of its principles, are rarely attempted by the uninitiated.
Comparatively few of those who read the reports on the New Westminster Bridge have very clear ideas of a great deal there put forth; they probably rise from the perusal with a vague notion that it is a great work, and that our engineers are miracles of cleverness, terribly tried by slow contractors. The fact is that engineering is too ponderous, and too responsible a profession to be lightly laid siege to; it has to deal with matter in its rudest forms, and requiring exactness and truthfulness in idea and performance lends no mystery to shroud the mistakes of even its most favoured votaries. Thus, though most of us have some knowledge of the slang, and can talk learnedly on subjects connected with law, physic, or divinity, though civilians have proved how much military and naval knowledge there really is among them, and though our ladies even are often wise on architectural matters, very few have a similarly extensive acquaintance either with the vocabulary or the leading principles of engineering science. We will therefore attempt to give a simple, untechnical exposition of the main features of the great metropolitan work now going on at Westminster. And as construction is ever a nobler work than destruction, let us who have heard much lately how French and Austrian armies break Italian bridges, spend half an hour in learning how we Englishmen build ours.
To make any attempt of this kind intelligible and connected, it will be necessary to give as rapid and comprehensive a sketch of the general design and proportions of the new bridge as possible, before we proceed to a more detailed view of the works themselves. Let therefore all readers given to laziness scruple not to skip several of the coming paragraphs, and so escape the hated “facts and figures.”
New Westminster Bridge will be of iron, and is to be built upon the site of the present structure; being, however, some 36 feet wider than the old bridge, it will cover the whole of the present area, and an additional 36 feet on the western side of the river. This increase in width will allow of the pulling down the old edifice, without involving any cessation of the traffic, and the western portion or “first half” of the bridge, as it is called, being now in course of erection close alongside the existing stone-work will, when opened, form the roadway over which the cabs, omnibuses, and foot-passengers will pass, while the old bridge will be quarried out, and cleared completely away to make room for the erection of the remaining width or “second half” of the new.
When this is completed, the river will be spanned by seven arches of elliptical form, varying in their openings from 120 feet in the widest, to 95 feet 9 inches in the narrowest. These arches are supported on granite piers, 10 feet 6 inches wide for the largest and 10 feet for the smallest, standing some 2 feet from the surface of the river at high tide. The headways of the arches, measured from high-water line, vary from 20 feet in the centre to 16 feet on the Surrey and Middlesex shores. These heights are below those of the present bridge; but let no invidious captain of a river steamer or revolutionary “call-boy,” fearing for their funnels, grow wrath thereupon; these dimensions were not lightly come by, a committee of the House of Commons having met, duly weighed evidence, and deliberated, before they were finally fixed upon, rightly considering that convenience of men and horses was of more importance than many funnels. The total length of the seven arches is 820 feet, and the total width of the roadway between the parapets 85 feet, of which 52 feet are carriage-way, and 16 feet on either side foot-way. Fifteen ribs forming the arches, and springing from the piers, make up this width. Each rib is composed of cast-iron, having for its centre or crown a girder of wrought-iron, and placed about 5 feet 3 inches apart under the carriage-way, and 7 feet apart under the footway. They are firmly held together, laterally, by connecting braces, and the whole covered in with plates of wrought-iron (called “buckled plates”) bolted to transverse bearers carried by the ribs, the paving and granite pitching of the roadway being laid over all. On either side of the bridge the ribs (being more useful than ornamental) are covered by a decorated face-work of iron, Gothic in design, and on this is carried the parapet, which is Gothic also. This parapet will be remarkably low, standing only 3 feet 5 inches from the footway, thus giving an uninterrupted view of the new palace.
Having now—we hope successfully—got over these dreaded facts, we are in a position to walk leisurely over the works, and describe the various details of the undertaking. In the present condition of the Thames we scarcely dare ask the boldest reader to don a diver’s dress, even in imagination, and examine into the construction of the new granite piers. The mere idea of such a bath would be too much for most people; and, as the minutest description of all their peculiarities may be found already published in the Parliamentary blue-books, we would refer the curious to those interesting works, and proceed at once to deal with the superstructure.
The iron-work for the new bridge has three separate stages of existence. The castings are made at Messrs. Cochrane’s works at Dudley, they are then delivered to the bridge works at Battersea Fields, where they are planed and fashioned to their proper shape, and are afterwards fixed on the piers at Westminster. Any frequent passenger by steam-boat, travelling between Chelsea and the east, cannot fail to have noticed the yard where the Westminster bridge works are now carried on. Situated under the shadow of the huge standpipes of the Southwark and Vauxhall Waterworks, and immediately opposite what were till lately Mr. Thomas Cubitt’s premises; this yard, with its travelling-cranes and low black arches of iron dotted irregularly about it, is sure to attract attention. It is here that by far the most interesting operations in connection with the work are being carried on, and it is here we propose to conduct the reader.
We take boat, then, and, braving the Thames’ foul smell, are carried rapidly up to Nine Elms pier. On landing, a walk of ten minutes brings us to a little black door, set in a range of black railing, with a dirty white board which bears an intimation that these premises are the property of her Majesty’s Commissioners, and the usual inscription, “No admittance except on business.” Having business, we enter, and find ourselves in a spacious yard. Immediately before us and right across the yard runs a tall scaffolding called a gauntry, carrying on its top two travelling-cranes. On our right a little arm of the river runs up, and the gauntry is carried out into and over the water, allowing the travellers to load and unload with the greatest facility, while on our left are the contractors’ temporary offices. Being franked everywhere, we enter these first, and spend half an hour pleasantly enough in looking over the drawings with the polite manager, and then return to the yard for a completer investigation.
Under the gauntry, on the space now before us, the whole work of the bridge is temporarily erected, in precisely the same way as it is afterwards permanently fixed at Westminster; and we stand now immediately under one of the widest arches of the bridge. The length of the gauntry is 350 feet, that of the bridge itself, 820 feet; three arches only, therefore, are erected here at one time: when complete, these are removed to their proper site, while others take their place. We see, then, a temporary erection which is a prototype of the true bridge. Beyond the gauntry the yard stretches to the river side, with the fitting and smiths’ shops in convenient positions. Large castings, arranged in apple-pie order, almost cover the ground; while between them miniature lines of railway run in every direction. Three more travelling-cranes run in parallel lines to the river: these are all busy now, picking up and removing the heavy castings, or unloading fresh arrivals from barges. Let us watch that piece now hanging from one of these gigantic gibbets, and follow its various adventures. It is, as we see, a rough casting, and to be fitted for its future destiny it must be planed to its proper form and dimensions — much in the same way, though by very different means, as the partially shaped stones of the mason are dressed into truth of surface and finish. The traveller has dropped it on one of the little trucks forming the only “rolling-stock” of these railways, and as it stops upon a turntable, we see in a moment that its passage is taken for the long black building on our left. This is the fitting-shop. Following the truck, we enter a large, well-lighted shop, in which the hum of machinery drowns every other sound: here, too, the little railways, with their turntables, branch in every direction; and ranged along the building are machines of various kinds. First, a drilling machine, next a lathe; in the corner yonder, a screwing machine; and beyond this others again. At one end of the shop is the steam-engine driving the whole; and at the other the foreman’s little glass-house. But the truck has stopped by the large planing-machine, and three or four men are, by the aid of a crane, laying the casting upon its side thereon. If we wait a few minutes while the piece is adjusted and fastened firmly down, we shall see the revolving cutting tools of the machine, like a ring of sharp, shining, steel teeth, tearing away at the rough iron, and leaving a perfectly true, smooth surface behind their track. As the machine cannot plane more than one superficial foot per hour, we will leave the remorseless teeth eating into the solid metal, growling over their meal like some hungry angry beast, and turn to another casting which, having been through this operation, is now laid down to undergo further tortures. To hold all the several parts of the iron-work together, it is necessary to use bolts and nuts; and here the drilling-machine is at work, boring the holes required. We suppose our casting planed and drilled, and follow it once more out of the shop,—still carried on the useful rails to the gauntry,—the traveller of which lifts it to its proper position, while the “erectors” are busy bolting together the finished pieces as they arrive. All day, and every day—nay, until lately, by night as well—this work was going on. Out of the smoke of Staffordshire, castings, almost daily arriving, and being unshipped from the barges, do not lie long in the yard. A constant stream of these pieces is pouring through the fitting-shop. All day long the shining teeth gnaw and growl savagely over their prey; all day the active drills eat their way into the metal, like some new kind of “teredo;” and ever there comes the finished work, true, from the machines. But we must leave the fitting-shop, though there is a magnetism about its operations which no one who visits it for the first time escapes.
Once more out of doors, we turn our steps to that portion of the yard devoted to the wrought-iron, or smiths’ work. Here are the old accompaniments of the trade — the anvil and the sledge, the bellows and the fires. We are now among the wrought-iron girders before described as forming the crowns of the arches: they are to be seen in every stage of manufacture, from the untouched plates fresh from the mills, to the finished work. Confusion seems to reign supreme in this quarter. Plates, bars, rivets, every form of iron lies about in masses. Girders, partly completed, sprawl helplessly over the ground; here and there others stand temporarily erected in much more orderly fashion, and are receiving the necessary bearers for carrying the buckled plates of the roadway. Elsewhere all is chaos: fire, smoke, hurry, bustle, the din of rivetting hammers, and apparent disorder, mixed up with a prevailing sense of intense busy-ness. The contrast is strange between all this and the comparatively quiet working of the machinery in the shop we have just left: there, nothing could appear slower or more leisurely than its operations; here, nothing could seem more noisy or bustling. Each is good in its place. The work being different, the means are necessarily different also. Near us is the punching and shearing shed, where the metal is cut, and pierced with such holes as may be required. Gangs of three or four men bring in plates of iron for punching. Behind us are two machines—their black forms and heavy proportions looking ogre-like in the smoky atmosphere—furnished with huge jaws, which slowly close and open: they shear through the thick plates as the men place them within their power, or rapidly pierce hole after hole with a smart “bang” through the metal. Plate after plate, and bar after bar is thus punched and sheared, and as they are finished each is built up into its place, and we follow them until the ring of the rivetters’ hammers, binding all firmly together, takes unaccustomed ears by storm, and drives us into the farthest corners of the yard, to take a peep at the operation of “buckling” the plates which are to carry the roadway. This buckling consists in giving to a flat plate of iron a dished or convex form. Round a furnace are grouped some six or eight men, hot, sooty, and lightly dressed: hard by stands a frame-work of wood carrying the “dies” by which the buckling is accomplished: within this, and firmly bedded on the ground, is a heavy mass of iron (the lower die), dished out to the form the plate is required to take; into this the top “die” fits, being made with a convex surface corresponding with the dishing in the bed. The upper “die” is lifted by hoisting tackle to a height of three feet; meanwhile, one of the sooty crew opens the furnace door, while his mates draw from its red mouth a heated plate. This they place upon the bed, a catch is pulled, the top “die” falls, and on being raised again, the plate is seen dished or “buckled” to the required form; it is removed from the press, and while still hot, thoroughly oiled; there are nearly 3000 of these plates required to cover the surface of the bridge, and they are buckled at a rate of about sixty plates per day. We must take a glance before we go at the “mould loft.” Over the fitting shop is a large room; on the carefully-laid and clean white floor of which we see a full-sized drawing, showing the contour of every arch of the bridge. Spreading over the boards in every direction, these lines, coloured black, blue, red, and green, seem to a stranger too complex for definite meaning. Each colour denotes a particular arch, and to practised eyes any one set is followed without difficulty or confusion.
Piled around this and the adjoining room are many wooden models, or “patterns ” of the castings, and in a corner we remark one for the Gothic parapet. At this moment workmen are busy here making other models for the ornamental facing to the ribs of the bridge. This decorated face-work has naturally excited some public interest, and consequently has been much criticised. Perhaps in all matters relating to decoration, there is nothing so completely without law as public taste, we will not, therefore, stay to examine into the merit or demerit of work on which it is pretty certain every man will have his own opinion; but in criticising ornamental iron-work, the practical man cannot forget that a faulty moulding may be the result of difficulties in casting, as he knows that a really successful imitation of the Gothic style, so peculiarly adapted to stone, is practically almost impossible in cast iron. The verdict of the public on this question will, however, soon be challenged. The contractors have already completed the iron-work for the “first half” of the bridge; with the exception of this face-work, which will be finished somewhat later. It then only remains for the engineer to complete the road and pathway, and open the bridge for traffic. One obstruction will, we fear, remain. The blocks of houses on either side of the river (ultimately destined to be removed), still look stable as ever—these abut directly upon the new portion of the structure, and will, if not removed before opening the bridge, make a sharp and inconvenient turn in the road necessary. These done away with, we Londoners, may fairly hope to cross the Thames -next year, by a bridge about nine feet lower than the present, and thirty-six feet wider when completely finished. As it will be impossible for our contractors to proceed with the destruction of the old bridge in the summary manner lately popular on the continent, we must for the present be content with the first half. It will not be long though before the pickaxe and the spade are busy at their work, and the present crippled arches become things of the past.
Either we, or the stones, seem to have degenerated since Shakespeare's time, for they, now-a-days, preach sermons, but to very few listeners—and are not often occasions for sentiment—but the passing away of old Westminster bridge, associated as it is with some of England’s most classic interests, may well suggest memories of noble men and noble deeds, now buried in the dead past. Many a patriot and many a plotter, passed over its footways into England’s senate. With or without reminder the glory of our great men will live among us ever; while the remembrance of our base ones will perish like its stones.
With bright thoughts of our dead worthies, we close this paper, hoping in the practical fashion of an engineer, that our new bridge may yet carry to our new Parliament houses hearts as true, as loyal, and fearless, as ever in old time aided to establish our freedom and our fame.
D. P.