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I need not say that we schoolboys appreciated his feat of foolhardiness far more than Telford's master work."
CHAPTER XIII.
DOCKS, DRAINAGE, AND BRIDGES.
It will have been observed, from the preceding narrative, how much had already been accomplished by skill and industry towards opening up the material resources of the kingdom. The stages of improvement which we have recorded indeed exhibit a measure of the vital energy which has from time to time existed in the nation. In the earlier periods of engineering history, the war of man was with nature.
The sea was held back by embankments. The Thames, instead of being allowed to overspread the wide marshes on either bank, was confined within limited bounds, by which the navigable depth of its channel was increased, at the same time that a wide extent of land was rendered available for agriculture.
In those early days, the great object was to render the land more habitable, comfortable, and productive. Marshes were reclaimed, and wastes subdued. But so long as the country remained comparatively closed against communication, and intercourse was restricted by the want of bridges and roads, improvement was extremely slow.
For, while roads are the consequence of civilisation, they are also among its most influential causes. We have seen even the blind Metcalf acting as an effective instrument of progress in the northern counties by the formation of long lines of road. Brindley and the Duke of Bridgewater carried on the work in the same districts, and conferred upon the north and north-west of England the blessings of cheap and effective water communication. Smeaton followed and carried out similar undertakings in still remoter places, joining the east and west coasts of Scotland by the Forth and Clyde Ca.n.a.l, and building bridges in the far north. Rennie made harbours, built bridges, and hewed out docks for s.h.i.+pping, the increase in which had kept pace with the growth of our home and foreign trade. He was followed by Telford, whose long and busy life, as we have seen, was occupied in building bridges and making roads in all directions, in districts of the country formerly inaccessible, and therefore comparatively barbarous. At length the wildest districts of the Highlands and the most rugged mountain valleys of North Wales were rendered as easy of access as the comparatively level counties in the immediate neighbourhood of the metropolis.
During all this while, the wealth and industry of the country had been advancing with rapid strides. London had grown in population and importance. Many improvements had been effected in the river, But the dock accommodation was still found insufficient; and, as the recognised head of his profession, Mr. Telford, though now grown old and fast becoming infirm, was called upon to supply the requisite plans. He had been engaged upon great works for upwards of thirty years, previous to which he had led the life of a working mason. But he had been a steady, temperate man all his life; and though nearly seventy, when consulted as to the proposed new docks, his mind was as able to deal with the subject in all its bearings as it had ever been; and he undertook the work.
In 1824 a new Company was formed to provide a dock nearer to the heart of the City than any of the existing ones. The site selected was the s.p.a.ce between the Tower and the London Docks, which included the property of St. Katherine's Hospital. The whole extent of land available was only twenty-seven acres of a very irregular figure, so that when the quays and warehouses were laid out, it was found that only about ten acres remained for the docks; but these, from the nature of the ground, presented an unusual amount of quay room. The necessary Act was obtained in 1825; the works were begun in the following year; and on the 25th of October, 1828, the new docks were completed and opened for business.
The St. Katherine Docks communicate with the river by means of an entrance tide-lock, 180 feet long and 45 feet wide, with three pairs of gates, admitting either one very large or two small vessels at a time. The lock-entrance and the sills under the two middle lock-gates were fixed at the depth of ten feet under the level of low water of ordinary spring tides. The formation of these dock-entrances was a work of much difficulty, demanding great skill on the part of the engineer. It was necessary to excavate the ground to a great depth below low water for the purpose of getting in the foundations, and the cofferdams were therefore of great strength, to enable them, when pumped out by the steam-engine, to resist the lateral pressure of forty feet of water at high tide.
The difficulty was, however, effectually overcome, and the wharf walls, locks, sills and bridges of the St. Katherine Docks are generally regarded as a master-piece of harbour construction.
Alluding to the rapidity with which the works were completed, Mr. Telford says: "Seldom, indeed never within my knowledge, has there been an instance of an undertaking; of this magnitude, in a very confined situation, having been perfected in so short a time;....
but, as a practical engineer, responsible for the success of difficult operations, I must be allowed to protest against such haste, pregnant as it was, and ever will be, with risks, which, in more instances than one, severely taxed all my experience and skill, and dangerously involved the reputation of the directors as well as of their engineer."
Among the remaining bridges executed by Mr. Telford, towards the close of his professional career, may be mentioned those of Tewkesbury and Gloucester. The former town is situated on the Severn at its confluence with the river Avon, about eleven miles above Gloucester. The surrounding district was rich and populous; but being intersected by a large river, without a bridge, the inhabitants applied to Parliament for powers to provide so necessary a convenience. The design first proposed by a local architect was a bridge of three arches; but Mr. Telford, when called upon to advise the trustees, recommended that, in order to interrupt the navigation as little as possible, the river should be spanned by a single arch; and he submitted a design of such a character, which was approved and subsequently erected. It was finished and opened in April, 1826.
This is one of the largest as well as most graceful of Mr. Telford's numerous cast iron bridges. It has a single span of 170 feet, with a rise of only 17 feet, consisting of six ribs of about three feet three inches deep, the spandrels being filled in with light diagonal work. The narrow Gothic arches in the masonry of the abutments give the bridge a very light and graceful appearance, at the same time that they afford an enlarged pa.s.sage for the high river floods.
The bridge at Gloucester consists of one large stone arch of 150 feet span. It replaced a structure of great antiquity, of eight arches, which had stood for about 600 years. The roadway over it was very narrow, and the number of piers in the river and the small dimensions of the arches offered considerable obstruction to the navigation. To give the largest amount of waterway, and at the same time reduce the gradient of the road over the bridge to the greatest extent, Mr. Telford adopted the following expedient.
He made the general body of the arch an ellipse, 150 feet on the chord-line and 35 feet rise, while the voussoirs, or external archstones, being in the form of a segment, have the same chord, with only 13 feet rise. "This complex form," says Mr. Telford, "converts each side of the vault of the arch into the shape of the entrance of a pipe, to suit the contracted pa.s.sage of a fluid, thus lessening the flat surface opposed to the current of the river whenever the tide or upland flood rises above the springing of the middle of the ellipse, that being at four feet above low water; whereas the flood of 1770 rose twenty feet above low water of an ordinary spring-tide, which, when there is no upland flood, rises only eight or nine feet."*[1] The bridge was finished and opened in 1828.
[Image] Dean Bridge, Edinburgh.
The last structures erected after our engineer's designs were at Edinburgh and Glasgow: his Dean Bridge at the former place, and his Jamaica Street Bridge at the latter, being regarded as among his most successful works. Since his employment as a journeyman mason at the building of the houses in Princes Street, Edinburgh, the New Town had spread in all directions. At each visit to it on his way to or from the Caledonian Ca.n.a.l or the northern harbours, he had been no less surprised than delighted at the architectural improvements which he found going forward. A new quarter had risen up during his lifetime, and had extended northward and westward in long lines of magnificent buildings of freestone, until in 1829 its further progress was checked by the deep ravine running along the back of the New Town, in the bottom of which runs the little Water of Leith. It was determined to throw a stone bridge across this stream, and Telford was called upon to supply the design. The point of crossing the valley was immediately behind Moray Place, which stands almost upon its verge, the sides being bold, rocky, and finely wooded. The situation was well adapted for a picturesque structure, such as Telford was well able to supply. The depth of the ravine to be spanned involved great height in the piers, the roadway being 106 feet above the level of the stream. The bridge was of four arches of 90 feet span each, and its total length 447 feet; the breadth between the parapets for the purposes of the roadway and footpaths being 39 feet.*[2] It was completed and opened in December, 1831.
But the most important, as it was the last, of Mr. Telford's stone bridges was that erected across the Clyde at the Broomielaw, Glasgow. Little more than fifty years since, the banks of the river at that place were literally covered with broom--and hence its name--while the stream was scarcely deep enough to float a herring-buss. Now, the Broomielaw is a quay frequented by s.h.i.+ps of the largest burden, and bustling with trade and commerce. Skill and enterprise have deepened the Clyde, dredged away its shoals, built quays and wharves along its banks, and rendered it one of the busiest streams in the world,
It has become a great river thoroughfare, worked by steam. On its waters the first steamboat ever constructed for purposes of traffic in Europe was launched by Henry Bell in 1812; and the Clyde boats to this day enjoy the highest prestige.
The deepening of the river at the Broomielaw had led to a gradual undermining of the foundations of the old bridge, which was situated close to the princ.i.p.al landing-place. A little above it, was an ancient overfall weir, which had also contributed to scour away the foundations of the piers. Besides, the bridge was felt to be narrow, inconvenient, and ill-adapted for accommodating the immense traffic pa.s.sing across the Clyde at that point. It was, therefore, determined to take down the old structure, and Build a new one; and Mr. Telford was called upon to supply the design.
The foundation was laid with great ceremony on the 18th of March, 1833, and the new bridge was completed and opened on the 1st of January, 1836, rather more than a year after the engineer's death. It is a very fine work, consisting of seven arches, segments of circles, the central arch being 58 feet 6 inches; the span of the adjoining arches diminis.h.i.+ng to 57 feet 9 inches, 55 feet 6 inches, and 52 feet respectively. It is 560 feet in length, with an open waterway of 389 feet, and its total width of carriageway and footpath is 60 feet, or wider, at the time it was built, than any river bridge in the kingdom.
[Image] Glasgow Bridge
Like most previous engineers of eminence--like Perry, Brindley, Smeaton, and Rennie--Mr. Telford was in the course of his life extensively employed in the drainage of the Fen districts. He had been jointly concerned with Mr. Rennie in carrying out the important works of the Eau Brink Cut, and at Mr. Rennie's death he succeeded to much of his practice as consulting engineer.
It was princ.i.p.ally in designing and carrying out the drainage of the North Level that Mr. Telford distinguished himself in Fen drainage. The North Level includes all that part of the Great Bedford Level situated between Morton's Leam and the river Welland, comprising about 48,000 acres of land. The river Nene, which brings down from the interior the rainfall of almost the entire county of Northampton, flows through nearly the centre of the district.
In some places the stream is confined by embankments, in others it flows along artificial outs, until it enters the great estuary of the Wash, about five miles below Wisbeach. This town is situated on another river which flows through the Level, called the Old Nene.
Below the point of junction of these rivers with the Wash, and still more to seaward, was South Holland Sluice, through which the waters of the South Holland Drain entered the estuary. At that point a great ma.s.s of silt had acc.u.mulated, which tended to choke up the mouths of the rivers further inland, rendering their navigation difficult and precarious, and seriously interrupting the drainage of the whole lowland district traversed by both the Old and New Nene. Indeed the sands were acc.u.mulating at such a rate, that the outfall of the Wisbeach River threatened to become completely destroyed.
Such being the state of things, it was determined to take the opinion of some eminent engineer, and Mr. Rennie was employed to survey the district and recommend a measure for the remedy of these great evils. He performed this service in his usually careful and masterly manner; but as the method which he proposed, complete though it was, would have seriously interfered with the trade of Wisbeach, by leaving it out of the line of navigation and drainage which he proposed to open up, the corporation of that town determined to employ another engineer; and Mr Telford was selected to examine and report upon the whole subject, keeping in view the improvement of the river immediately adjacent to the town of Wisbeach.
Mr. Telford confirmed Mr. Rennie's views to a large extent, more especially with reference to the construction of an entirely new outfall, by making an artificial channel from Kindersleys Cut to Crab-Hole Eye anchorage, by which a level lower by nearly twelve feet would be secured for the outfall waters; but he preferred leaving the river open to the tide as high as Wisbeach, rather than place a lock with draw-doors at Lutton Leam Sluice, as had been proposed by Mr. Rennie. He also suggested that the acute angle at the Horseshoe be cut off and the river deepened up to the bridge at Wisbeach, making a new cut along the bank on the south side of the town, which should join the river again immediately above it, thereby converting the intermediate s.p.a.ce, by draw-doors and the usual contrivances, into a floating dock. Though this plan was approved by the parties interested in the drainage, to Telford's great mortification it was opposed by the corporation of Wisbeach, and like so many other excellent schemes for the improvement of the Fen districts, it eventually fell to the ground.
The cutting of a new outfall for the river Nene, however, could not much longer be delayed without great danger to the reclaimed lands of the North Level, which, but for some relief of the kind, must shortly have become submerged and reduced to their original waste condition. The subject was revived in 1822, and Mr. Telford was again called upon, in conjunction with Sir John Rennie, whose father had died in the preceding year, to submit a plan of a new Nene Outfall; but it was not until the year 1827 that the necessary Act was obtained, and then only with great difficulty and cost, in consequence of the opposition of the town of Wisbeach. The works consisted princ.i.p.ally of a deep cut or ca.n.a.l, about six miles in length, penetrating far through the sand banks into the deep waters of the Wash. They were begun in 1828, and brought to completion in 1830, with the most satisfactory results. A greatly improved outfall was secured by thus carrying. the mouths of the rivers out to sea, and the drainage of the important agricultural districts through which the Nene flows was greatly benefited; while at the same time nearly 6000 acres of valuable corn-growing land were added to the county of Lincoln.
But the opening of the Nene Outfall was only the first of a series of improvements which eventually included the whole of the valuable lands of the North Level, in the district situated between the Nene and the Welland. The opening at Gunthorpe Sluice, which was the outfall for the waters of the Holland Drain, was not less than eleven feet three inches above low water at Crab-Hole; and it was therefore obvious that by lowering this opening a vastly improved drainage of the whole of the level district, extending from twenty to thirty miles inland, for which that sluice was the artificial outlet, would immediately be secured. Urged by Mr. Telford, an Act for the purpose of carrying out the requisite improvement was obtained in 1830, and the excavations having been begun shortly after, were completed in 1834.
A new cut was made from Clow's Cross to Gunthorpe Sluice, in place of the winding course of the old s.h.i.+re Drain; besides which, a bridge was erected at Cross Keys, or Sutton Wash, and an embankment was made across the Salt Marshes, forming a high road, which, with the bridges previously erected at Fossd.y.k.e and Lynn, effectually connected the counties of Norfolk and Lincoln. The result of the improved outfall was what the engineer had predicted. A thorough natural drainage was secured for an extensive district, embracing nearly a hundred thousand acres of fertile land, which had before been very ineffectually though expensively cleared of the surplus water by means of windmills and steam-engines. The productiveness of the soil was greatly increased, and the health and comfort of the inhabitants promoted to an extent that surpa.s.sed all previous expectation.
The whole of the new cuts were easily navigable, being from 140 to 200 feet wide at bottom, whereas the old outlets had been variable and were often choked with s.h.i.+fting sand. The district was thus effectually opened up for navigation, and a convenient transit afforded for coals and other articles of consumption. Wisbeach became accessible to vessels of much larger burden, and in the course of a few years after the construction of the Nene Outfall, the trade of the port had more than doubled. Mr. Telford himself, towards the close of his life, spoke with natural pride of the improvements which he had thus been in so great a measure instrumental in carrying out, and which had so materially promoted the comfort, prosperity, and welfare of a very extensive district.*[3]
We may mention, as a remarkable effect of the opening of the new outfall, that in a few hours the lowering of the waters was felt throughout the whole of the Fen level. The sluggish and stagnant drains, cuts, and leams in far distant places, began actually to flow; and the sensation created was such, that at Thorney, near Peterborough, some fifteen miles from the sea, the intelligence penetrated even to the congregation then sitting in church--for it was Sunday morning--that "the waters were running!" when immediately the whole flocked out, parson and all, to see the great sight, and acknowledge the blessings of science. A humble Fen poet of the last century thus quaintly predicted the moral results likely to arise from the improved drainage of his native district:-
"With a change of elements suddenly There shall a change of men and manners be; Hearts thick and tough as hides shall feel remorse, And souls of sedge shall understand discourse; New hands shall learn to work, forget to steal, New legs shall go to church, new knees to kneel."
The prophecy has indeed been fulfilled. The barbarous race of Fen-men has disappeared before the skill of the engineer. As the land has been drained, the half-starved fowlers and fen-roamers have subsided into the ranks of steady industry--become farmers, traders, and labourers. The plough has pa.s.sed over the bed of Holland Fen, and the agriculturist reaps his increase more than a hundred fold.. Wide watery wastes, formerly abounding in fish, are now covered with waving crops of corn every summer. Sheep graze on the dry bottom of Whittlesea Mere, and kine low where not many years since the silence of the waste was only disturbed by the croaking of frogs and the screaming of wild fowl. All this has been the result of the science of the engineer, the enterprise of the landowner, and the industry of our peaceful army of skilled labourers.*[4]
Footnotes for Chapter XIII.
*[1] Telford's Life, p261
*[2] The piers are built internally with hollow compartments, as at the Menai Bridge, the side walls being 3 feet thick and the cross walls 2 feet. Projecting from the piers and abutments are pilasters of solid masonry. The main arches have their springing 70 feet from the foundations and rise 30 feet; and at 20 feet higher, other arches, of 96 feet span and 10 feet rise, are constructed; the face of these, projecting before the main arches and spandrels, producing a distinct external soffit of 5 feet in breadth.
This, with the peculiar piers, const.i.tutes the princ.i.p.al distinctive feature in the, bridge.
*[3] "The Nene Outfall channel," says Mr. Tycho Wing, "was projected by the late Mr. Rennie in 1814, and executed jointly by Mr. Telford and the present Sir John Rennie. But the scheme of the North Level Drainage was eminently the work of Mr. Telford, and was undertaken upon his advice and responsibility, when only a few persons engaged in the Nene Outfall believed that the latter could be made, or if made, that it could be maintained. Mr. Telford distinguished himself by his foresight and judicious counsels at the most critical periods of that great measure, by his unfailing confidence in its success, and by the boldness and sagacity which prompted him to advise the making of the North Level drainage, in full expectation of the results for the sake of which the Nene Outfall was undertaken, and which are now realised to the extent of the most sanguine hopes."
*[4] Now that the land actually won has been made so richly productive, the engineer is at work with magnificent schemes of reclamation of lands at present submerged by the sea. The Norfolk Estuary Company have a scheme for reclaiming 50,000 acres; the Lincolns.h.i.+re Estuary Company, 30,000 acres; and the Victoria Level Company, 150,000 acres--all from the estuary of the Wash. By the process called warping, the land is steadily advancing upon the ocean, and before many years have pa.s.sed, thousands of acres of the Victoria Level will have been reclaimed for purposes of agriculture.
CHAPTER XIV.
SOUTHEY'S TOUR IN THE HIGHLANDS.
While Telford's Highland works were in full progress, he persuaded his friend Southey, the Poet Laureate, to accompany him on one of his visits of inspection, as far north as the county of Sutherland, in the autumn of 1819. Mr. Southey, as was his custom, made careful notes of the tour, which have been preserved,*[1] and consist in a great measure of an interesting resume of the engineer's operations in harbour-making, road-making, and ca.n.a.l-making north of the Tweed.
Southey reached Edinburgh by the Carlisle mail about the middle of August, and was there joined by Mr. Telford, and Mr. and Mrs.
Rickman,*[2] who were to accompany him on the journey. They first proceeded to Linlithgow, Bannockburn,*[3] Stirling, Callendar, the Trosachs, and round by the head of Loch Earn to Killin, Kenmore, and by Aberfeldy to Dunkeld. At the latter place, the poet admired Telford's beautiful bridge, which forms a fine feature in the foreground of the incomparable picture which the scenery of Dunkeld always presents in whatever aspect it is viewed.
From Dunkeld the party proceeded to Dundee, along the left bank of the Firth of Tay. The works connected with the new harbour were in active progress, and the engineer lost no time in taking his friend to see them. Southey's account is as follows:--
"Before breakfast I went with Mr. Telford to the harbour, to look at his works, which are of great magnitude and importance: a huge floating dock, and the finest graving dock I ever saw. The town expends 70,000L. on these improvements, which will be completed in another year. What they take from the excavations serves to raise ground which was formerly covered by the tide, but will now be of the greatest value for wharfs, yards, &c. The local authorities originally proposed to build fifteen piers, but Telford a.s.sured them that three would be sufficient; and, in telling me this, he said the creation of fifteen new Scotch peers was too strong a measure....
"Telford's is a happy life; everywhere making roads, building bridges, forming ca.n.a.ls, and creating harbours--works of sure, solid, permanent utility; everywhere employing a great number of persons, selecting the most meritorious, and putting them forward in the world in his own way."
After the inspection at Dundee was over, the party proceeded on their journey northward, along the east coast:--
"Near Gourdon or Bervie harbour, which is about a mile and a half on this side the town, we met Mr. Mitch.e.l.l and Mr. Gibbs, two of Mr. Telford's aides-de-camp, who had come thus far to meet him. The former he calls his 'Tartar,' from his cast of countenance, which is very much like a Tartar's, as well as from his Tartar-like mode of life; for, in his office of overseer of the roads, which are under the management of the Commissioners, he travels on horseback not less than 6000 miles a year. Mr. Telford found him in the situation of a working mason, who could scarcely read or write; but noticing him for his good conduct, his activity, and his firm steady character, he, has brought him forward; and Mitch.e.l.l now holds a post of respectability and importance, and performs his business with excellent ability."
After inspecting the little harbour of Bervie, one of the first works of the kind executed by Telford for the Commissioners, the party proceeded by Stonehaven, and from thence along the coast to Aberdeen. Here the harbour works were visited and admired:--
"The quay," says Southey, "is very fine; and Telford has carried out his pier 900 feet beyond the point where Smeaton's terminated.