Metcalfe & Telford V.
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CHAPTER X.

CALEDONIAN AND OTHER CANALS.
 

Loch Lochy, part of the route of the Caledonian Canal.  Picture Wikipedia.


THE formation of a navigable highway through the chain of locks lying in the Great Glen of the Highlands, and extending diagonally across Scotland from the Atlantic to the North Sea, had long been regarded as a work of national importance.   As early as 1773, James Watt, then following the business of a land-surveyor at Glasgow, made a survey of the country at the instance of the Commissioners of Forfeited Estates.   He pronounced the canal practicable, and pointed out how it could best be constructed.  There was certainly no want of water, for Watt was repeatedly drenched with rain while he was making his survey, and he had difficulty in preserving even his journal book.  "On my way home," he says, "I passed through the wildest country I ever saw, and over the worst conducted roads."

    Twenty years later, in 1793, Mr. Rennie was consulted as to the canal, and he also prepared a scheme: but nothing was done.  The project was, however, revived in 1801 during the war with Napoleon, when various inland ship canals—such as those from London to Portsmouth, and from Bristol to the English Channel—were under consideration with the view of enabling British shipping to pass from one part of the kingdom to another without being exposed to the attacks of French privateers.  But there was another reason for urging the formation of the canal through the Great Glen of Scotland, which was regarded as of considerable importance before the introduction of steam enabled vessels to set the winds and tides at comparative defiance.  It was this: vessels sailing from the eastern ports to America had to beat up the Pentland Frith, often against adverse winds and stormy seas, which rendered the navigation both tedious and dangerous.  Thus it was cited by Sir Edward Parry, in his evidence before Parliament in favour of completing the Caledonian Canal, that of two vessels despatched from Newcastle on the same day—one bound for Liverpool by the north of Scotland, and the other for Bombay by the English Channel and the Cape of Good Hope—the latter reached its destination first!  Another case may be mentioned, that of an Inverness vessel, which sailed for Liverpool on a Christmas Day, reached Stromness Harbour, in Orkney, on the 1st of January, and lay there windbound, with a fleet of other traders, until the middle of April following!  In fact, the Pentland Frith, which is the throat connecting the Atlantic and German Oceans, through which the former rolls its long majestic waves with tremendous force, was long the dread of mariners, and it was considered an object of national importance to mitigate the dangers of the passage towards the western seas.

    As the lochs occupying the chief part of the bottom of the Great Glen were of sufficient depth to be navigable by large vessels, it was thought that if they could be connected by a ship canal, so as to render the line of navigation continuous, it would be used by shipping to a large extent, and prove of great public service.  Five hundred miles of dangerous navigation by the Orkneys and Cape Wrath would thereby be saved, while ships of war, were this track open to them, might reach the north of Ireland in two days from Fort George near Inverness.

    When the scheme of the proposed canal was revived in 1801, Mr. Telford was requested to make a survey and send in his report on the subject.  He immediately wrote to his friend James Watt, saying, "I have so long accustomed myself to look with a degree of reverence at your work, that I am particularly anxious to learn what occurred to you in this business while the whole was fresh in your mind.  The object appears to me so great and so desirable, that I am convinced you will feel a pleasure in bringing it again under investigation, and I am very desirous that the thing should be fully and fairly explained, so that the public may be made aware of its extensive utility.  If I can accomplish this, I shall have done my duty; and if the project is not executed now, some future period will see it done, and I shall have the satisfaction of having followed you and promoted its success."  We may here state that Telford's survey agreed with Watt's in the most important particulars, and that he largely cited Watt's descriptions of the proposed scheme in his own report.

    Mr. Telford's first inspection of the district was made in 1801, and his report was sent in to the Treasury in the course of the following year.  Lord Bexley, then Secretary to the Treasury, took a warm personal interest in the project, and lost no opportunity of actively promoting it.  A board of commissioners was eventually appointed to carry out the formation of the canal.  Mr. Telford, on being appointed principal engineer of the undertaking, was requested at once to proceed to Scotland and prepare the necessary working survey.  He was accompanied on the occasion by Mr. Jessop as consulting engineer.  Twenty thousand pounds were granted under the provisions of the 43 Geo. III. (chap. cii.), and the works were commenced, in the beginning of 1804, by the formation of a dock or basin adjoining the intended tide-lock at Corpach, near Bannavie.

 

 


    The basin at Corpach formed the southernmost point of the intended canal.  It is situated at the head of Loch Eil, amidst some of the grandest scenery of the Highlands.  Across the Loch is the little town of Fort William, one of the forts established at the end of the seventeenth century to keep the wild Highlanders in subjection.  Above it rise hills over hills, of all forms and sizes, and of all hues, from grass-green below to heather-brown and purple above, capped with heights of weather-beaten grey; while towering over all stands the rugged mass of Ben Nevis a mountain almost unsurpassed for picturesque grandeur.  Along the western foot of the range, which extends for some six or eight miles, lies a long extent of brown bog, on the verge of which, by the river Lochy, stand the ruins of Inverlochy Castle.

    The works at Corpach involved great labour, and extended over a long series of years.  The difference between the level of Loch Ell and Loch Lochy is ninety feet, while the distance between them was less than eight miles.  It was therefore necessary to climb up the side of the hill by a flight of eight gigantic locks, clustered together, and which Telford named Neptune's Staircase.  The ground passed over was in some places very difficult, requiring large masses of embankment, the slips of which in the course of the work frequently occasioned serious embarrassment.  The basin on Loch Ell, on the other hand, was constructed amidst rock, and considerable difficulty was experienced in getting in the necessary cofferdam for the construction of the opening into the sea-lock, the entrance-sill of which was laid upon the rock itself, so that there was a depth of 21 feet of water upon it at high water of neap tides.

 

Neptune's Staircase on the Caledonian Canal at Banavie, near Fort William.
Eight locks ascend 64 feet (19.5 metres).  Picture Wikipedia.


    At the same time that the works at Corpach were begun, the dock or basin at the north-eastern extremity of the canal, situated at Clachnaharry, on the shore of Loch Beauly, was also laid out, and the excavations and embankments were carried on with considerable activity.  This dock was constructed about 967 yards long, and upwards of 162 yards in breadth, giving an area of about 32 acres,—forming, in fact, a harbour for the vessels using the canal.  The dimensions of the artificial waterway were of unusual size, as the intention was to adapt it throughout for the passage of a 32-gun frigate of that day, fully equipped and laden with stores.  The canal, as originally resolved upon, was designed to be 110 feet wide at the surface, and 50 feet at the bottom, with a depth in the middle of 20 feet; though these dimensions were somewhat modified in the execution of the work.  The locks were of corresponding large dimensions, each being from 170 to 180 feet long, 40 broad, and 20 deep.

 

The Clachnaharry swing bridge looking towards the final stretch of the Caledonian Canal -
the sea lock and Beauly Firth.  Picture Wikimedia Commons.


    Between these two extremities of the canal—Corpach on the south-west and Clachnaharry on the north-east—extends the chain of fresh-water lochs: Loch Lochy on the south; next Loch Oich; then Loch Ness; and lastly, furthest north, the small Loch of Dochfour.  The whole length of the navigation is 60 miles 40 chains, of which the navigable lochs constitute about 40 miles, leaving only about 20 miles of canal to be constructed, but of unusually large dimensions and through a very difficult country.

 


    The summit loch of the whole is Loch Oich, the surface of which is exactly a hundred feet above high water-mark, both at Inverness and Fort William; and to this sheet of water the navigation climbs up by a series of locks from both the eastern and western seas.  The whole number of these is twenty-eight: the entrance-lock at Clachnaharry, constructed on piles, at the end of huge embankments, forced out into deep water, at Loch Beauly; another at the entrance to the capacious artificial harbour above mentioned, at Muirtown; four connected locks at the southern end of this basin; a regulating lock a little to the north of Loch Dochfour; five contiguous locks at Fort Augustus, at the south end of Loch Ness; another, called the Kytra Lock, about midway between Fort Augustus and Loch Oich; a regulating lock at the north-east end of Loch Oich; two contiguous locks between Lochs Oich and Lochy; a regulating lock at the southwest end of Loch Lochy; next, the grand series of locks, eight in number, called "Neptune's Staircase," at Bannavie, within a mile and a quarter of the sea; two locks, descending to Corpach basin; and lastly, the great entrance or sea-lock at Corpach.

 

The Caledonian Canal at Fort Augustus.  Picture Wikimedia Commons.


    The northern entrance-lock from the sea at Loch Beauly is at Clachnaharry, near Inverness.  The works here were not accomplished without much difficulty as well as labour, partly from the very gradual declivity of the shore, and partly from the necessity of placing the sea-lock on absolute mud, which afforded no foundation other than what was created by compression and pile-driving.  The mud was forced down by throwing upon it an immense load of earth and stones, which was left during twelve months to settle; after which a shaft was sunk to a solid foundation, and the masonry of the sea-lock was then founded and built therein.

 


    In the 'Sixteenth Report of the Commissioners of the Caledonian Canal,' the following reference is made to this important work, which was finished in 1812: "The depth of the mud on which it may be said to be artificially seated is not less than 60 feet; so that it cannot be deemed superfluous, at the end of seven years, to state that no subsidence is discoverable; and we presume that the entire lock, as well as every part of it, may now be deemed as immovable, and as little liable to destruction, as any other large mass of masonry.  This was the most remarkable work performed under the immediate care of Mr. Matthew Davidson, our superintendent at Clachnaharry, from 1804 till the time of his decease.  He was a man perfectly qualified for the employment by inflexible integrity, unwearied industry, and zeal to a degree of anxiety, in all the operations committed to his care." [p.291]
 
    As may naturally be supposed, the execution of these great works involved vast labour and anxiety.  They were designed with much skill, and executed with equal ability.  There were lock-gates to be constructed, principally of cast iron, sheathed with pine planking.  Eight public road bridges crossed the line of the canal, which were made of cast iron, and swung horizontally.  There were many mountain streams, swollen to torrents in winter, crossing under the canal, for which abundant water-way had to be provided, involving the construction of numerous culverts, tunnels, and under-bridges of large dimensions.  There were also powerful sluices to let off the excess of water sent down from the adjacent mountains into the canal during winter.  Three of these, of great size, high above the river Lochy, are constructed at a point where the canal is cut through the solid rock; and the sight of the mass of waters rushing down into the valley beneath, gives an impression of power which, once seen, is never forgotten.

    These great works were only brought to a completion after the labours of many years, during which the difficulties encountered in their construction had swelled the cost of the canal far beyond the original estimate.  The rapid advances which had taken place in the interval in the prices of labour and materials also tended greatly to increase the expenses, and, after all, the canal, when completed and opened, was comparatively little used.  This was doubtless owing, in a great measure, to the rapid changes which occurred in the system of navigation shortly after the projection of the undertaking.  For these Telford was not responsible.  He was called upon to make the canal, and he did so in the best manner.  Engineers are not required to speculate as to the commercial value of the works they are required to construct; and there were circumstances connected with the scheme of the Caledonian Canal which removed it from the category of mere commercial adventures.  It was a Government project, and it proved a failure as a paying concern.  Hence it formed a prominent topic for discussion in the journals of the day; but the attacks made upon the Government because of their expenditure on the hapless undertaking were perhaps more felt by Telford, who was its engineer, than by all the ministers of state conjoined.

    "The unfortunate issue of this great work," writes the present engineer of the canal, to whom we are indebted for many of the preceding facts, "was a grievous disappointment to Mr. Telford, and was in fact the one great bitter in his otherwise unalloyed cup of happiness and prosperity. The undertaking was maligned by thousands who knew nothing of its character.  It became 'a dog with a bad name,' and all the proverbial consequences followed.  The most absurd errors and misconceptions were propagated respecting it from year to year, and it was impossible during Telford's lifetime to stem the torrent of popular prejudice and objurgation.  It must, however, be admitted, after a long experience, that Telford was greatly over-sanguine in his expectations as to the national uses of the canal, and he was doomed to suffer acutely in his personal feelings, little though he may have been personally to blame, the consequences of what in this commercial country is regarded as so much worse than a crime, namely, a financial mistake." [p.293]

    Mr. Telford's great sensitiveness made him feel the ill success of this enterprise far more than most other men would have done.  He was accustomed to throw himself into the projects on which he was employed with an enthusiasm almost poetic.  He regarded them not merely as so much engineering, but as works which were to be instrumental in opening up the communications of the country and extending its civilisation.  Viewed in this light, his canals, roads, bridges, and harbours were unquestionably of great national importance, though their commercial results might not in all cases justify the estimates of their projectors.  To refer to like instances—no one can doubt the immense value and public uses of Mr. Rennie's Waterloo Bridge or Mr. Robert Stephenson's Britannia and Victoria Bridges, though every one knows that, commercially, they have been failures.  But it is probable that neither of these eminent engineers gave himself anything like the anxious concern that Telford did about the financial issue of his undertaking.  Were railway engineers to fret and vex themselves about the commercial value of the schemes in which they have been engaged, there are few of them but would be so haunted by the ghosts of wrecked speculations that they could scarcely lay their heads upon their pillows for a single night in peace.

    While the Caledonian Canal was in progress, Mr. Telford was occupied in various works of a similar kind in England and Scotland, and also upon one in Sweden.  In 1804, while on one of his journeys to the north, he was requested by the Earl of Eglinton and others to examine a project for making a canal from Glasgow to Saltcoats and Ardrossan, on the north-western coast of the county of Ayr, passing near the important manufacturing town of Paisley.  A new survey of the line was made, and the works were carried on during several successive years until a very fine capacious canal was completed, on the same level, as far as Paisley and Johnstown.  But the funds of the company falling short, the works were stopped, and the canal was carried no further.  Besides, the measures adopted by the Clyde Trustees to deepen the bed of that river and enable ships of large burden to pass up as high as Glasgow, had proved so successful that the ultimate extension of the canal to Ardrossan was no longer deemed necessary, and the prosecution of the work was accordingly abandoned.  But as Mr. Telford has observed, no person suspected, when the canal was laid out in 1805, "that steamboats would not only monopolise the trade of the Clyde, but penetrate into every creek where there is water to float them, in the British Isles and the continent of Europe, and be seen in every quarter of the world."

    Another of the navigations on which Mr. Telford was long employed was that of the river Weaver in Cheshire.  It was only twenty-four miles in extent, but of considerable importance to the country through which it passed, accommodating the salt-manufacturing districts, of which the towns of Nantwich, Northwich, and Frodsham are the centres.  The channel of the river was extremely crooked and much obstructed by shoals, when Telford took the navigation in hand in the year 1807, and a number of essential improvements were made in it, by means of new locks, weirs, and side cuts, which had the effect of greatly improving the communications of these important districts.

    In the following year we find our engineer consulted, at the instance of the King of Sweden, on the best mode of constructing the Gotha Canal, between Lake Wenern and the Baltic, to complete the communication with the North Sea.  In 1808, at the invitation of Count Platen, Mr. Telford visited Sweden and made a careful survey of the district.  The service occupied him and his assistants two months, after which he prepared and sent in a series of detailed plans and sections, together with an elaborate report on the subject.  His plans having been adopted, he again visited Sweden in 1810, to inspect the excavations which had already been begun, when he supplied the drawings for the locks and bridges.  With the sanction of the British Government, he at the same time furnished the Swedish contractors with patterns of the most improved tools used in canal making, and took with him a number of experienced lock-makers and navvies for the purpose of instructing the native workmen.

    The construction of the Gotha Canal was an undertaking of great magnitude and difficulty, similar in many respects to the Caledonian Canal, though much more extensive.  The length of artificial canal was 55 miles, and of the whole navigation, including the lakes, 120 miles.  The locks are 120 feet long and 24 feet broad; the width of the canal at bottom being 42 feet, and the depth of water 10 feet.  The results, so far as the engineer was concerned, were much more satisfactory than in the case of the Caledonian Canal.  While in the one case he had much obloquy to suffer for the services he had given, in the other he was honoured and feted as a public benefactor, the King conferring upon him the Swedish order of knighthood, and presenting him with his portrait set in diamonds.

 

One of the cruise ships that now ply the Gotha Canal [p.296].  Photo courtesy Wendy Austin.


    Among the various canals throughout England which Mr. Telford was employed to construct or improve, down to the commencement of the railway era, were the Gloucester and Berkeley Canal, in 1818; [p.297-1] the Grand Trunk Canal, in 1822; [p.297-2] the Harecastle Tunnel, which he constructed anew, in 1824-7; the Birmingham Canal, in 1824; [p.297-3] and the Macclesfield, and Birmingham and Liverpool Junction Canals, in 1825.  The Gloucester and Berkeley Canal Company had been unable to finish their works, begun some thirty years before; but with the assistance of a loan of £160,000 from the Exchequer Bill Loan Commissioners, they were enabled to proceed with the completion of their undertaking. A capacious canal was cut from Gloucester to Sharpness Point, about sixteen miles down the Severn, which had the effect of greatly improving the convenience of the port of Gloucester; and by means of this navigation, ships of large burden can now avoid the circuitous and difficult passage of the higher part of the river, very much to the advantage of the trade of the place.

 

The start of the Birmingham Canal at Gas Street Basin, central Birmingham.  Picture Wikipedia.


    The formation of a new tunnel through Harecastle Hill, for the better accommodation of the boats passing along the Grand Trunk Canal, was a formidable work.  The original tunnel, it will be remembered, [p.298] was laid out by Brindley, about fifty years before, and occupied eleven years in construction.  But the engineering appliances of those early days were very limited; the pumping powers of the steam-engine had not been fairly developed, and workmen were as yet only half-educated in the expert use of tools.  The tunnel, no doubt, answered the purpose for which it was originally intended, but it was very soon found too limited for the traffic passing along the navigation.  It was little larger than a sewer, and admitted the passage of only one narrow boat, seven feet wide, at a time, involving very heavy labour on the part of the men who worked it through.  This was performed by what was called legging.  The Leggers lay upon the deck of the vessel, or upon a board slightly projecting from either side of it, and, by thrusting their feet against the slimy roof or sides of the tunnel—walking horizontally as it were—they contrived to push it through.  But it was no better than horse-work; and after "legging" Harecastle Tunnel, which is more than a mile and a half long, the men were usually completely exhausted, and as wet from perspiration as if they had been dragged through the canal itself.  The process occupied about two hours, and by the time the passage of the tunnel was made, there was usually a collection of boats at the other end waiting their turn to pass.  Thus much contention and confusion took place amongst the boatmen—a very rough class of labourers—and many furious battles were fought by the claimants for the first turn "through."  Regulations were found of no avail to settle these disputes, still less to accommodate the large traffic which continued to keep flowing along the line of the Grand Trunk, and steadily increased with the advancing trade and manufactures of the country.  Loud complaints were made by the public, but they were disregarded for many years; and it was not until the proprietors were threatened with rival canals and railroads that they determined on—what they could no longer avoid if they desired to retain the carrying trade of the district—the enlargement of the Harecastle Tunnel.

    Mr. Telford was requested to advise the Company what course was most proper to be adopted in the matter, and after examining the place, he recommended that an entirely new tunnel should be constructed, nearly parallel with the old one, but of much larger dimensions.  The work was begun in 1824, and completed in 1827, in less than three years.  There were at that time throughout the country plenty of skilled labourers and contractors, many of them trained by their experience upon Telford's own works, whereas Brindley had in a great measure to make his workmen out of the rawest material.  Telford also had the advantage of greatly improved machinery and an abundant supply of money—the Grand Trunk Canal Company having become prosperous and rich, paying large dividends.  It is therefore meet, while eulogising the despatch with which he was enabled to carry out the work, to point out that the much greater period occupied in the earlier undertaking is not to be set down to the disparagement of Brindley, who had difficulties to encounter which the later engineer knew nothing of.

    The length of the new tunnel is 2,926 yards; it is 16 feet high and 14 feet broad, 4 feet 9 inches of the breadth being occupied by the towing-path—for "legging" was now dispensed with, and horses hauled along the boats instead of their being thrust through by men.  The tunnel is in so perfectly straight a line that its whole length can be seen through at one view; and though it was constructed by means of fifteen different pitshafts sunk to the same line along the length of the tunnel, the workmanship is so perfect that the joinings of the various lengths of brickwork are scarcely discernible.  The convenience afforded by the new tunnel was very great, and Telford mentions that, on surveying it in 1829, he asked a boatman coming out of it how he liked it?  "I only wish," he replied, "that it reached all the way to Manchester!"

 


    At the time that Mr. Telford was engaged upon the tunnel at Harecastle, he was employed to improve and widen the Birmingham Canal, another of Brindley's works.  Though the accommodation provided by it had been sufficient for the traffic when originally constructed, the expansion of the trade of Birmingham and the neighbourhood, accelerated by the formation of the canal itself, had been such as completely to outgrow its limited convenience and capacity, and it's enlargement and improvement now became absolutely necessary.  Brindley's Canal, for the sake of cheapness of construction—money being much scarcer and more difficult to be raised in the early days of canals—was also winding and crooked; and it was considered desirable to shorten and straighten it by cutting off the bends at different places.  At the point at which the canal entered Birmingham, it had become "little better than a crooked ditch, with scarcely the appearance of a towing-path, the horses frequently sliding and staggering in the water, the hauling-lines sweeping the gravel into the canal, and the entanglement at the meeting of boats being incessant; whilst at the locks at each end of the short summit at Smethwick crowds of boatmen were always quarrelling, or offering premiums for a preference of passage; and the mine-owners, injured by the delay, were loud in their just complaints." [p.301]

    Mr. Telford proposed an effective measure of improvement, which was taken in hand without loss of time, and carried out, greatly to the advantage of the trade of the district.  The numerous bends in the canal were cut off, the water-way was greatly widened, the summit at Smethwick was cut down to the level on either side, and a straight canal, forty feet wide, without a lock, was thus formed as far as Bilston and Wolverhampton; while the length of the main line between Birmingham and Autherley, along the whole extent of the "Black country," was reduced from twenty-two to fourteen miles.  At the same time the obsolete curvatures in Brindley's old canal were converted into separate branches or basins, for the accommodation of the numerous mines and manufactories on either side of the main line.  In consequence of the alterations which had been made in the canal, it was found necessary to construct numerous large bridges.  One of these—a cast iron bridge, at Galton, of 150 feet span—has been much admired for its elegance, lightness, and economy of material.  Several others of cast iron were constructed at different points, and at one place the canal itself is carried along on an aqueduct of the same material as at Pont-Cysylltau.  The whole of these extensive improvements were carried out in the short space of two years'; and the result was highly satisfactory, "proving," as Mr. Telford himself observes, "that where business is extensive, liberal expenditure of this kind is true economy."

 

 

Telford's Galton Bridge (1829), Smethwick, West Midlands.  Picture Wikipedia.


    In 1825 Mr. Telford was called upon to lay out a canal to connect the Grand Trunk, at the north end of Harecastle Tunnel, with the rapidly improving towns of Congleton and Macclesfield.  The line was twenty-nine miles in length, ten miles on one level from Harecastle to beyond Congleton; then, ascending 114 feet by eleven locks, it proceeded for five miles on a level past Macclesfield, and onward to join the Peak Forest Canal at Marple.  The navigation was thus conducted upon two levels, each of considerable length; and it so happened that the trade of each was in a measure distinct, and required separate accommodation.  The traffic of the whole of the Congleton district had ready access to the Grand Trunk system, without the labour, expense, and delay involved by passing the boats through locks; while the coals brought to Macclesfield to supply the mills there were carried throughout upon the upper level, also without lockage.  The engineer's arrangement proved highly judicious, and furnishes an illustration of the tact and judgment which he usually displayed in laying out his works for practical uses.  Mr. Telford largely employed cast iron in the construction of this canal, using it in the locks and gates, as well as in an extensive aqueduct which it was necessary to construct over a deep ravine, after the plan pursued by him at Pont-Cysylltau and other places.

    The last canal constructed by Mr. Telford was the Birmingham and Liverpool Junction, extending from the Birmingham Canal, near Wolverhampton, in nearly a direct line, by Market Drayton, Nantwich, and through the city of Chester, by the Ellesmere Canal, to Ellesmere Port on the Mersey.  The proprietors of canals were becoming alarmed at the numerous railways projected through the districts heretofore served by their water-ways; and among other projects one was set on foot, as early as 1825, for constructing a line of railway from London to Liverpool.  Mr. Telford was consulted as to the best means of protecting existing investments, and his advice was to render the canal system as complete as it could be made; for he entertained the conviction, which has been justified by experience, that such navigations possessed peculiar advantages for the conveyance of heavy goods, and that, if the interruptions presented by locks could be done away with, or materially reduced, a large portion of the trade of the country must continue to be carried by the water roads.  The new line recommended by him was approved and adopted, and the works commenced in 1826.  A second complete route was thus opened up between Birmingham and Liverpool, and Manchester, by which the distance was shortened twelve miles, and the delay occasioned by 320 feet of upward and downward lockage was done away with.

    Telford was justly proud of his canals, which were the finest works of their kind that had yet been executed in England.  Capacious, convenient, and substantial, they embodied his most ingenious contrivances, and his highest engineering skill.  Hence we find him writing to a friend at Langholm, that, so soon as he could find "sufficient leisure from his various avocations in his own unrivalled and beloved island," it was his intention to visit France and Italy, for the purpose of ascertaining what foreigners had been able to accomplish, compared with ourselves, in the construction of canals, bridges, and harbours.  "I have no doubt," said he, "as to their inferiority.  During the war just brought to a close, England has not only been able to guard her own head and to carry on a gigantic struggle, but at the same time to construct canals, roads, harbours, bridges—magnificent works of peace—the like of which are probably not to be found in the world.  Are not these things worthy of a nation's pride?"


――――♦――――

 
CHAPTER XI.

TELFORD AS A ROAD-MAKER.


MR. TELFORD'S extensive practice as a bridge-builder led his friend Southey to designate him "Pontifex Maximus."  Besides the numerous bridges erected by him in the West of England, we have found him furnishing designs for about twelve hundred in the Highlands, of various dimensions, some of stone and others of iron.  His practice in bridge-building had, therefore, been of an unusually extensive character, and Southey's sobriquet was not ill applied.  But besides being a great bridge-builder, Telford was also a great road-maker.  With the progress of industry and trade, the easy and rapid transit of persons and goods had come to be regarded as an increasing object of public interest.  Fast coaches now ran regularly between all the principal towns of England; every effort being made, by straightening and shortening the roads, cutting down hills, and carrying embankments across valleys and viaducts over rivers, to render travelling by the main routes as easy and expeditious as possible.

    Attention was especially turned to the improvement of the longer routes, and to perfecting the connection of London with the chief towns of Scotland and Ireland.  Telford was early called upon to advise as to the repairs of the road between Carlisle and Glasgow, which had been allowed to fall into a wretched state; as well as the formation of a new line from Carlisle, across the counties of Dumfries, Kirkcudbright, and Wigton, to Port Patrick, for the purpose of ensuring a more rapid communication with Belfast and the northern parts of Ireland.  Although Glasgow had become a place of considerable wealth and importance, the roads to it, north of Carlisle, continued in a very unsatisfactory state.  It was only in July, 1788, that the first mail-coach from London had driven into Glasgow by that route, when it was welcomed by a procession of the citizens on horseback, who went out several miles to meet it.  But the road had been shockingly made, and before long had become almost impassable.  Robert Owen states that, in 1795, it took him two days and three nights' incessant travelling to get from Manchester to Glasgow, and he mentions that the coach had to cross a well-known dangerous mountain at midnight, called Erickstane Brae, which was then always passed with fear and trembling. [p.306-1]

    As late as the year 1814 we find a Parliamentary Committee declaring the road between Carlisle and Glasgow to be in so ruinous a state as often seriously to delay the mail and endanger the lives of travellers.  The bridge over Evan Water was so much decayed, that one day the coach and horses fell through it into the river, when "one passenger was killed, the coachman survived only a few days, and several other persons were dreadfully maimed; two of the horses being also killed." [p.306-2]  The remaining part of the bridge continued for some time unrepaired, just space enough being left for a single carriage to pass.  The road trustees seemed to be helpless, and did nothing; a local subscription was tried and failed, the district passed through being very poor; but as the road was absolutely required for more than merely local purposes, it was eventually determined to undertake its reconstruction as a work of national importance, and £50,000 was granted by Parliament with this object, under the provisions of the Act passed in 1816.  The works were placed under Mr. Telford's charge; and an admirable road was very shortly under construction between Carlisle and Glasgow.  That part of it between Hamilton and Glasgow, eleven miles in length, was however left in the hands of local trustees, as was the diversion of thirteen miles at the boundary of the counties of Lanark and Dumfries, for which a previous Act had been obtained.  The length of new line constructed by Mr. Telford was sixty-nine miles, and it was probably the finest piece of road which up to that time had been made.

    His ordinary method of road-making in the Highlands was, first to level and drain; then, like the Romans, to lay a solid pavement of large stones, the round or broad end downwards, as close as they could be set.  The points of the latter were then broken off, and a layer of stones broken to about the size of walnuts, were laid upon them, and over all a little gravel if at hand.  A road thus formed soon became bound together, and for ordinary purposes was very durable.

    But where the traffic, as in the case of the Carlisle and Glasgow road, was expected to be very heavy, Telford took much greater pains.  Here he paid special attention to two points: first, to lay it out as nearly as possible upon a level, so as to reduce the draught to horses dragging heavy vehicles,—one in thirty being about the severest gradient at any part of the road.  The next point was to make the working, or middle portion of the road, as firm and substantial as possible, so as to bear, without shrinking, the heaviest weight likely to be brought over it.  With this object he specified that the metal bed was to be formed in two layers, rising about four inches towards the centre --the bottom course being of stones (whinstone, limestone, or hard freestone), seven inches in depth.  These were to be carefully set by hand, with the broadest ends downwards, all cross-bonded or jointed, no stone being more than three inches wide on the top.  The spaces between them were then to be filled up with smaller stones, packed by hand, so as to bring the whole to an even and firm surface.  Over this a top course was to be laid, seven inches in depth, consisting of properly broken hard whinstones, none exceeding six ounces in weight, and each to be able to pass through a circular ring, two inches and a half in diameter; a binding of gravel, about an inch in thickness, being placed over all.  A drain crossed under the bed of the bottom layer to the outside ditch in every hundred yards.  The result was an admirably easy, firm, and dry road, capable of being travelled upon in all weathers, and standing in comparatively small need of repairs.

 


    A similar practice was introduced in England about the same time by Mr. Macadam; and, though his method was not so thorough as that of Telford, it was usefully employed on most of the high roads throughout the kingdom.  Mr. Macadam's notice was first called to the subject while acting as one of the trustees of a road in Ayrshire.  Afterwards, while employed as Government agent for victualling the navy in the western parts of England, he continued the study of road-making, keeping in view the essential conditions of a compact and durable substance and a smooth surface.  At that time the attention of the Legislature was not so much directed to the proper making and mending of the roads, as to suiting the vehicles to them such as they were; and they legislated backwards and forwards for nearly half a century as to the breadth of wheels.  Macdam was, on the other hand, of opinion that the main point was to attend to the nature of the roads on which the vehicles were to travel.  Most roads were then made with gravel, or flints tumbled upon them in their natural state, and so rounded that they had no points of contact, and rarely became consolidated.  When a heavy vehicle of any sort passed over them, their loose structure presented no resistance; the material was thus completely disturbed, and they often became almost impassable.  Macadam's practice was this: to break the stones into angular fragments, so that a bed several inches in depth should be formed, the material best adapted for the purpose being fragments of granite, greenstone, or basalt; to watch the repairs of the road carefully during the process of consolidation, filling up the inequalities caused by the traffic passing over it, until a hard and level surface had been obtained.  Thus made, the road would last for years without further attention.  In 1815 Mr. Macadam devoted himself with great enthusiasm to road-making as a profession, and being appointed surveyor-general of the Bristol roads, he had full opportunities of exemplifying his system.  It proved so successful that the example set by him was quickly followed over the entire kingdom.  Even the streets of many large towns were Macadamised.  In carrying out his improvements, however, Mr. Macadam spent several thousand pounds of his own money, and in 1825, having proved this expenditure before a Committee of the House of Commons, the amount was reimbursed to him, together with an honorary tribute of two thousand pounds.  Mr. Macadam died poor, but, as he himself said, "at least an honest man."  By his indefatigable exertions and his success as a road-maker, by greatly saving animal labour, facilitating commercial intercourse, and rendering travelling easy and expeditious, he entitled himself to the reputation of a public benefactor.

 

Construction of the first road in the United States (1823) on the principles of
John Loudon McAdam (1756-1836). [p.311]  Picture Wikipedia.


    Owing to the mountainous nature of the country through which Telford's Carlisle and Glasgow road passes, the bridges are unusually numerous and of large dimensions.  Thus, the Fiddler's Burn Bridge is of three arches, one of 150 and two of 105 feet span each.  There are fourteen other bridges, presenting from one to three arches, of from 20 to go feet span.  But the most picturesque and remarkable bridge constructed by Telford in that district was upon another line of road subsequently carried out by him, in the upper part of the county of Lanark, and crossing the main line of the Carlisle and Glasgow road almost at right angles.  Its northern and eastern part formed a direct line of communication between the great cattle markets of Falkirk, Grief, and Doune, and Carlisle and the West of England.  It was carried over deep ravines by several lofty bridges, the most formidable of which was that across the Mouse Water at Cartland Crags, about a mile to the west of Lanark.  The stream here flows through a deep rocky chasm, the sides of which are in some places about four hundred feet high.  At a point where the height of the rocks is considerably less, but still most formidable, Telford spanned the ravine with the beautiful bridge represented in the engraving on page 311, its parapet being 129 feet above the surface of the water beneath.

 


    The reconstruction of the western road from Carlisle to Glasgow, which Telford had thus satisfactorily carried out, shortly led to similar demands from the population on the eastern side of the kingdom.  The spirit of road reform was now fairly on foot.  Fast coaches and wheel-carriages of all kinds had become greatly improved, so that the usual rate of travelling had advanced from five or six to nine or ten miles an hour.  The desire for the rapid communication of political and commercial intelligence was found to increase with the facilities for supplying it; and, urged by the public wants, the Post-Office authorities were stimulated to unusual efforts in this direction.  Numerous surveys were made and roads laid out, so as to improve the main line of communication between London and Edinburgh and the intermediate towns.  The first part of this road taken in hand was the worst—that lying to the north of Catterick Bridge, in Yorkshire.  A new line was surveyed by West Auckland to Hexham, passing over Carter Fell to Jedburgh, and thence to Edinburgh; but was rejected as too crooked and uneven.  Another was tried by Aldstone Moor and Bewcastle, and rejected for the same reason.  The third line proposed was eventually adopted as the best, passing from Morpeth, by Wooler and Coldstream, to Edinburgh; saving rather more than fourteen miles between the two points, and securing a line of road of much more favourable gradients.

 

Cartland Crags Bridge: picture from "Scotland Illustrated" by William Beattie, 1838.


    The principal bridge on this new highway was at Pathhead, over the Tyne, about eleven miles south of Edinburgh.  To maintain the level, so as to avoid the winding of the road down a steep descent on one side of the valley and up an equally steep ascent on the other, Telford ran out a lofty embankment from both sides, connecting their ends by means of a spacious bridge.  The structure at Pathhead is of five arches, each 50 feet span, with 25 feet rise from their springing, 49 feet above the bed of the river.  Bridges of a similar character were also thrown over the deep ravines of Cranston Dean and Cotty Burn, in the same neighbourhood.  At the same time a useful bridge was built on the same line of road at Morpeth, in Northumberland, over the river Wansbeck.  It consisted of three arches, of which the centre one was 50 feet span, and two side-arches 40 feet each; the breadth between the parapets being 30 feet.

    The advantages derived from the construction of these new roads were found to be so great, that it was proposed to do the like for the remainder of the line between London and Edinburgh; and at the instance of the Post-Office authorities, with the sanction of the Treasury, Mr. Telford proceeded to make detailed surveys of an entire new post-road between London and Morpeth.  In laying it out, the main points which he endeavoured to secure were directness and flatness; and 100 miles of the proposed new Great North Road, south of York, were laid out in a perfectly straight line.  This survey, which was begun in 1824, extended over several years; and all the requisite arrangements had been made for beginning the works, when the result of the locomotive competition at Rainhill, in 1829, had the effect of directing attention to that new method of travelling, fortunately in time to prevent what would have proved, for the most part, an unnecessary expenditure, on works soon to be superseded by a totally different order of things.

    The most important road-improvements actually carried out under Mr. Telford's immediate superintendence were those on the western side of the island, with the object of shortening the distance and facilitating the communication between London and Dublin by way of Holyhead, as well as between London and Liverpool.  At the time of the Union, the mode of transit between the capital of Ireland and the metropolis of the United Kingdom was tedious, difficult, and full of peril.  In crossing the Irish Sea to Liverpool, the packets were frequently tossed about for days together.  On the Irish side, there was scarcely the pretence of a port, the landing-place being within the bar of the river Liffey, inconvenient at all times, and in rough weather extremely dangerous.  To avoid the long voyage to Liverpool, the passage began to be made from Dublin to Holyhead, the nearest point of the Welsh coast.  Arrived there, the passengers were landed upon rugged, unprotected rocks, without a pier or landing convenience of any kind. [p.316]  But the traveller's perils were not at an end, comparatively speaking they had only begun.  From Holyhead, across the island of Anglesea, there was no made road, but only a miserable track, circuitous and craggy, full of terrible jolts, round bogs and over rocks, for a distance of twenty-four miles.  Having reached the Menai Strait, the passengers had again to take to an open ferry-boat before they could gain the main land.  The tide ran with great rapidity through the Strait, and, when the wind blew strong, the boat was liable to be driven far up or down the channel, and was sometimes swamped altogether.  The perils of the Welsh roads had next to be encountered, and these were in as bad a condition at the beginning of the present century as those of the Highlands above described.  Through North Wales they were rough, narrow, steep, and unprotected, mostly unfenced, and in winter almost impassable.  The whole traffic on the road between Shrewsbury and Bangor was conveyed by a small cart, which passed between the two places once a week in summer.  As an illustration of the state of the roads in South Wales, which were quite as bad as those in the North, we may state that, in 1803, when the late Lord Sudeley took home his bride from the neighbourhood of Welshpool to his residence only thirteen miles distant, the carriage in which the newly married pair rode stuck in a quagmire, and the occupants, having extricated themselves from their perilous situation, performed the rest of their journey on foot.

    The first step taken was to improve the landing-places on both the Irish and Welsh sides of St. George's Channel, and for this purpose Mr. Rennie was employed in 1801.  The result was, that Howth on the one coast, and Holyhead on the other, were fixed upon as the most eligible sites for packet stations.  Improvements, however, proceeded slowly, and it was not until 1810 that a sum of £10,000 was granted by Parliament to enable the necessary works to be begun.  Attention was then turned to the state of the roads, and here Mr. Telford's services were called into requisition.  As early as 1808 it had been determined by the Post-Office authorities to put on a mail-coach between Shrewsbury and Holyhead; but it was pointed out that the roads in North Wales were so rough and dangerous that it was doubtful whether the service could be conducted with safety.  Attempts were made to enforce the law with reference to their repair, and no less than twenty-one townships were indicted by the Postmaster-General.  The route was found too perilous even for a riding post, the legs of three horses having been broken in one week. [p.318]  The road across Anglesea was quite as bad.  Sir Henry Parnell mentioned, in 1819, that the coach had been overturned beyond Gwynder, going down one of the hills, when a friend of his was thrown a considerable distance from the roof into a pool of water.  Near the post-office of Gwynder, the coachman had been thrown from his seat by a violent jolt, and broken his leg.  The post-coach, and also the mail, had been overturned at the bottom of Penmyndd Hill; and the route was so dangerous that the London coachmen, who had been brought down to "work" the country, refused to continue the duty because of its excessive dangers.  Of course, anything like a regular mail-service through such a district was altogether impracticable.

    The indictments of the townships proved of no use; the localities were too poor to provide the means required to construct a line of road sufficient for the conveyance of mails and passengers between England and Ireland.  The work was really a national one, to be carried out at the national cost.  How was this best to be done?  Telford recommended that the old road between Shrewsbury and Holyhead (109 miles long) should be shortened by about four miles, and made as nearly as possible on a level; the new line proceeding from Shrewsbury by Llangollen, Corwen, Bettws-y-Coed, Capel-Curig, and Bangor, to Holyhead.  Mr. Telford also proposed to cross the Menai Strait by means of a cast iron bridge, hereafter to be described.

    Although a complete survey was made in 1811, nothing was done for several years.  The mail-coaches continued to be overturned, and stagecoaches, in the tourist season, to break down as before. [p.319]  The Irish mail-coach took forty-one hours to reach Holyhead from the time of its setting out from St. Martin's-le-Grand; the journey was performed at the rate of only 6¾ miles an hour, the Mail arriving in Dublin on the third day.  The Irish members made many complaints of the delay and dangers to which they were exposed in travelling up to town.  But, although there was much discussion, no money was voted until the year 1815, when Sir Henry Parnell vigorously took the question in hand and successfully carried it through.  A Board of Parliamentary Commissioners was appointed, of which he was chairman, and, under their direction, the new Shrewsbury and Holyhead road was at length commenced and carried to completion, the works extending over a period of about fifteen years.  The same Commissioners exercised an authority over the roads between London and Shrewsbury; and numerous improvements were also made in the main line at various points, with the object of facilitating communication between London and Liverpool as well as between London and Dublin.

 


    The rugged nature of the country through which the new road passed, along the slopes of rocky precipices and across inlets of the sea, rendered it necessary to build many bridges, to form many embankments, and cut away long stretches of rock, in order to secure an easy and commodious route.  The line of the valley of the Dee, to the west of Llangollen, was selected, the road proceeding along the scarped sides of the mountains, crossing from point to point by lofty embankments where necessary; and, taking into account the character of the country, it must be acknowledged that a wonderfully level road was secured.  While the gradients on the old road had in some cases been as steep as 1 in 6½, passing along the edge of unprotected precipices, the new one was so laid out as to be no more than 1 in 20 at any part, while it was wide and well protected along its whole extent.  Mr. Telford pursued the same system that he had adopted in the formation of the Carlisle and Glasgow road, as regards metalling, cross-draining, and fence-walling; for the latter purpose using schistus, or slate rubble-work, instead of sandstone.  The largest bridges were of iron; that at Bettws-y-Coed, over the Conway—called the Waterloo Bridge, constructed in 1815—being a very fine specimen of Telford's iron bridge-work.

 

Betws-y-Coed iron bridge;
the famous Waterloo Bridge. [p.321]
  © Copyright Ray Jones and licensed for reuse under this Creative Commons Licence.


    Those parts of the road which had been the most dangerous were taken in hand first, and, by the year 1819, the route had been rendered comparatively commodious and safe.  Angles were cut off, the sides of hills were blasted away, and several heavy embankments run out across formidable arms of the sea.  Thus, at Stanley Sands, near Holyhead, an embankment was formed 1300 yards long and 16 feet high, with a width of 34 feet at the top, along which the road was laid.  Its breadth at the base was 114 feet, and both sides were coated with rubble stones, as a protection against storms.  By the adoption of this expedient, a mile and a half was saved in a distance of six miles.  Heavy embankments were also run out, where bridges were thrown across chasms and ravines, to maintain the general level.  From Ty-Gwynn to Lake Ogwen, the road along the face of the rugged hill and across the river Ogwen was entirely new made, of a uniform width of 28 feet between the parapets, with an inclination of only 1 in 22 in the steepest place.  A bridge was thrown over the deep chasm forming the channel of the Ogwen, the embankment being carried forward from the rock cutting, protected by high breastworks.  From Capel-Curig to near the great waterfall over the river Lugwy, about a mile of new road was cut; and a still greater length from Bettws across the river Conway and along the face of Dinas Hill to Rhyddlanfair, a distance of 3 miles; its steepest descent being 1 in 22, diminishing to 1 in 45.  By this improvement, the most difficult and dangerous pass along the route through North Wales was rendered safe and commodious.  Another point of almost equal difficulty occurred near Ty-Nant, through the rocky pass of Glynn Duffrws, where the road was confined between steep rocks and rugged precipices: there the way was widened and flattened by blasting, and thus reduced to the general level; and so on eastward to Llangollen and Chirk, where the main Shrewsbury road to London was joined. [p.323]

 


    By means of these admirable roads the traffic of North Wales continues to be mainly carried on to this day.  Although railways have superseded coach-roads in the more level districts, the hilly nature of Wales precludes their formation in that quarter to any considerable extent; and even in the event of railways being constructed, a large part of the traffic of every country must necessarily continue to pass over the old high roads.  Without them even railways would be of comparatively little value; for a railway station is of use chiefly because of its easy accessibility, and thus, both for passengers and merchandise, the common roads of the country are as useful as ever they were, though the main post-roads have in a great measure ceased to be employed for the purposes for which they were originally designed.

    The excellence of the roads constructed by Mr. Telford through the formerly inaccessible counties of North Wales was the theme of general praise; and their superiority, compared with those of the richer and more level districts in the midland and western English counties, becoming the subject of public comment, he was called upon to execute like improvements upon that part of the post-road which extended between Shrewsbury and the metropolis.  A careful survey was made of the several routes from London northward by Shrewsbury as far as Liverpool; and the short line by Coventry, being 153 miles from London to Shrewsbury, was selected as the one to be improved to the utmost.

    Down to 1819, the road between London and Coventry was in a very bad state, being so laid as to become a heavy slough in wet weather.  There were many steep hills which required to be cut down, in some parts of deep clay, in others of deep sand.  A mail-coach had been tried to Banbury; but the road below Aylesbury was so bad, that the Post-Office authorities were obliged to give it up.  The twelve miles from Towcester to Daventry were still worse.  The line of way was covered with banks of dirt; in winter it was a puddle of from four to six inches deep quite as bad as it had been in Arthur Young's time; and when horses passed along the road, they came out of it a mass of mud and mire. [p.325]  There were also several steep and dangerous hills to be crossed; and the loss of horses by fatigue in travelling by that route at the time was very great.

    Even the roads in the immediate neighbourhood of the metropolis were little better, those under the Highgate and Hampstead trust being pronounced in a wretched state.  They were badly formed, on a clay bottom, and being undrained, were almost always wet and sloppy.  The gravel was usually tumbled on and spread unbroken, so that the materials, instead of becoming consolidated, were only rolled about by the wheels of the carriages passing over them.

    Mr. Telford applied the same methods in the reconstruction of these roads that he had already adopted in Scotland and Wales, and the same improvement was shortly felt in the more easy passage over them of vehicles of all sorts, and in the great acceleration of the mail service.  At the same time, the line along the coast from Bangor, by Conway, Abergele, St. Asaph, and Holywell, to Chester, was greatly improved.  As forming the mail road from Dublin to Liverpool, it was considered of importance to render it as safe and level as possible.  The principal new cuts on this line were those along the rugged skirts of the huge Penmaen-Mawr; around the base of Penmaen-Bach to the town of Conway; and between St. Asaph and Holywell, to ease the ascent of Rhyall Hill.

    But more important than all, as a means of completing the main line of communication between England and Ireland, there were the great bridges over the Conway and the Menai Straits to be constructed.  The dangerous ferries at those places had still to be crossed in open boats, sometimes in the night, when the luggage and mails were exposed to great risks.  Sometimes, indeed, they were wholly lost, and passengers were lost with them.  It was therefore determined, after long consideration, to erect bridges over these formidable straits, and Mr. Telford was employed to execute the works,—in what manner, we propose to describe in the next chapter.


――――♦―――

 
CHAPTER XII.

THE MENAI AND CONWAY BRIDGES.

 

Menai Suspension Bridge;
view along the bridge from the Anglesey side at low tide.
© Copyright Nigel Mykura and licensed for reuse under this Creative Commons Licence.


SO long as the dangerous Straits of Menai had to be crossed in an open ferry-boat, the communication between London and Holyhead was necessarily considered incomplete.  While the roads through North Wales were so dangerous as to deter travellers between England and Ireland from using that route, the completion of the remaining link of communication across the Straits was of comparatively little importance.  But when those roads had, by the application of much capital, skill, and labour, been rendered so safe and convenient that the mail and stage coaches could run over them at the rate of from eight to ten miles an hour, the bridging of the Straits became a measure of urgent public necessity. The increased traffic by this route so much increased the quantity of passengers and luggage, that the open boats were often dangerously overloaded; and serious accidents, attended with loss of life and property, came to be of frequent occurrence.

    The erection of a bridge over the Straits had long been matter of speculation amongst engineers.  As early as 1776, Mr. Colborne proposed his plan of an embankment with a bridge in the middle of it; and a few years later, in 1785, Mr. Nichols proposed a wooden viaduct, furnished with drawbridges at Cadnant Island.  Later still, Mr. Rennie proposed his design of a cast iron bridge.  But none of these plans were carried out, and the whole subject remained in abeyance until the year 1810, when a commission was appointed to inquire and report as to the state of the roads between Shrewsbury, Chester, and Holyhead.  The result was, that Mr. Telford was called upon to report as to the most effectual method of bridging the Menai Strait, and thus completing the communication with the port of embarkation for Ireland.

 


    Mr. Telford submitted alternative plans for a bridge over the Strait: one at the Swilly Rock, consisting of three cast iron arches of 260 feet span, with a stone arch of 100 feet span between each two iron ones, to resist their lateral thrust; and another at Ynys-y-moch, to which he himself attached the preference, consisting of a single cast iron arch of 500 feet span, the crown of the arch to be 100 feet above high water of spring tides, and the breadth of the roadway to be 40 feet.

 


    The principal objection taken to this plan by engineers generally, was the supposed difficulty of erecting a proper centering to support the arch during construction; and the mode by which Mr. Telford proposed to overcome this may be cited in illustration of his ready ingenuity in overcoming difficulties.  He proposed to suspend the centering from above instead of supporting it from below in the usual manner—a contrivance afterwards revived by another very skilful engineer, the late Mr. Brunel.  Frames, 50 feet high, were to be erected on the top of the abutments, and on these, strong blocks, or rollers and chains, were to be fixed, by means of which, and by the aid of windlasses and other mechanical powers, each separate piece of centering was to be raised into, and suspended in, its proper place.  Mr. Telford regarded this method of constructing centres as applicable to stone as well as to iron arches; and indeed it is applicable, as Mr. Brunel held, to the building of the arch itself. [p.330]  Mr. Telford anticipated that, if the method recommended by him were successfully adopted on the large scale proposed at Menai, all difficulties with regard to carrying bridges over deep ravines would be done away with, and a new era in bridge-building begun.  For this and other reasons—but chiefly because of the much greater durability of a cast iron bridge compared with the suspension bridge afterwards adopted—it is matter of regret that he was not permitted to carry out this novel and grand design.  It was, however, again objected by mariners that the bridge would seriously affect, if not destroy, the navigation of the Strait; and this plan, like Mr. Rennie's, was eventually rejected.

 

 


    Several years passed, and during the interval Mr. Telford was consulted as to the construction of a bridge over Runcorn Gap on the Mersey, above Liverpool.  As the river was there about 1200 feet wide, and much used for purposes of navigation, a bridge of the ordinary construction was found inapplicable.  But as he was required to furnish a plan of the most suitable structure, he proceeded to consider how the difficulties of the case were to be met.  The only practicable plan, he thought, was a bridge constructed on the principle of suspension.  Expedients of this kind had long been employed in India and America, where wide rivers were crossed by means of bridges formed of ropes and chains; and even in this country a suspension bridge, though of a very rude kind, had long been in use near Middleton on the Tees, where, by means of two common chains stretched across the river, upon which a footway of boards was laid, the colliers were enabled to pass from their cottages to the colliery on the opposite bank.

    Captain (afterwards Sir Samuel) Brown took out a patent for forming suspension bridges in 1817; but it appears that Telford's attention had been directed to the subject before this time, as he was first consulted respecting the Runcorn Bridge in the year 1814, when he proceeded to make an elaborate series of experiments on the tenacity of wrought iron bars, with the object of employing this material in his proposed structure.  After he had made upwards of two hundred tests of malleable iron of various qualities, he proceeded to prepare his design of a bridge, which consisted of a central opening of 1000 feet span, and two side openings of 500 feet each, supported by pyramids of masonry placed near the low-water lines.  The roadway was to be 30 feet wide, divided into one central footway and two distinct carriageways of 12 feet each.  At the same time he prepared and submitted a model of the central opening, which satisfactorily stood the various strains which were applied to it.  This Runcorn design of 1814 was of a very magnificent character, perhaps superior even to that of the Menai Suspension Bridge, afterwards erected; but unhappily the means were not forthcoming to carry it into effect.  The publication of his plan and report had, however, the effect of directing public attention to the construction of bridges on the suspension principle; and many were shortly after designed and erected by Telford and other engineers in different parts of the kingdom.

 


    Mr. Telford continued to be consulted by the Commissioners of the Holyhead Roads as to the completion of the last and most important link in the line of communication between London and Holyhead, by bridging the and at one of their meetings in 1815, shortly after the publication of his Runcorn design, the inquiry was made whether a bridge upon the same principle was not applicable in this particular case.  The engineer was instructed again to examine the Straits and submit a suitable plan and estimate, which he proceeded to do in the early part of 1818.  The site selected by him as the most favourable was that which had been previously fixed upon for the projected cast iron bridge, namely at Ynys-y-moch—the shores there being bold and rocky, affording easy access and excellent foundations, while by spanning the entire channel between the low-water lines, and the roadway being kept uniformly 100 feet above the highest water at spring tide, the whole of the navigable waterway would be left entirely uninterrupted.  The distance between the centres of the supporting pyramids was proposed to be of the then unprecedented width of 550 feet, and the height of the pyramids 53 feet above the level of the roadway.  The main chains were to be sixteen in number, with a deflection of 37 feet, each composed of thirty-six bars of half-inch-square iron, so placed as to give a square of six on each side, making the whole chain about four inches in diameter, welded together for their whole length, secured by bucklings, and braced round with iron wire; while the ends of these great chains were to be secured by a mass of masonry built over stone arches between each end of the supporting piers and the adjoining shore.  Four of the arches were to be on the Anglesea, and three on the Caernarvonshire side, each of them of 52 feet 6 inches span.  The roadway was to be divided, as in the Runcorn design—with a carriageway 12 feet wide on each side, and a footpath of 4 feet in the middle.  Mr. Telford's plan was supported by Mr. Rennie and other engineers of eminence; and the Select Committee of the House of Commons, being satisfied as to its practicability, recommended Parliament to pass a Bill and to make a grant of money to enable the work to be carried into effect.

    The necessary Act passed in the session of 1818, and Mr. Telford immediately proceeded to Bangor to make preparations for beginning the works.  The first proceeding was to blast off the inequalities of the surface of the rock called Ynys-y-moch, situated on the western or Holyhead side of the Strait, at that time accessible only at low water.  The object was to form an even surface upon it for the foundation of the west main pier.  It used to be at this point, where the Strait was narrowest, that horned cattle were driven down, preparatory to swimming them across the channel to the Caernarvon side, when the tide was weak and at its lowest ebb.  The cattle were, nevertheless, often carried away, the current being too strong for the animals to contend against it.

    At the same time, a landing-quay was erected on Ynys-y-moch, which was connected with the shore by an embankment carrying lines of railway.  Along these, horses drew the sledges laden with stone required for the work; the material being brought in barges from the quarries opened at Penmon Point, on the north-eastern extremity of the Isle of Anglesea, a little to the westward of the northern opening of the Strait.  When the surface of the rock had been levelled and the causeway completed, the first stone of the main pier was laid by Mr. W. A. Provis, the resident engineer, on the l0th of August, 1819; but not the slightest ceremony was observed on the occasion.

    Later in the autumn, preparations were made for proceeding with the foundations of the eastern main pier on the Bangor side of the Strait.  After excavating the beach to a depth of 7 feet, a solid mass of rock was reached, which served the purpose of an immoveable foundation for the pier.  At the same time, workshops were erected; builders, artisans, and labourers were brought together from distant quarters; vessels and barges were purchased or built for the special purpose of the work; a quay was constructed at Penmon Point for loading the stones for the piers; and all the requisite preliminary arrangements were made for proceeding with the building operations in the ensuing spring.

    A careful specification of the masonry work was drawn up, and the contract was let to Messrs. Stapleton and Hall; but as they did not proceed satisfactorily, and desired to be released from the contract, it was relet on the same terms to Mr. John Wilson, one of Mr. Telford's principal contractors for mason work on the Caledonian Canal.  The building operations were begun with great vigour early in 1820.  The three arches on the Caernarvonshire side and the four on the Angle-sea side were first proceeded with.  They are of immense magnitude, and occupied four years in construction, having been finished late in the autumn of 1824.  These piers are 65 feet in height from high-water line to the springing of the arches, the span of each being 52 feet 6 inches.  The work of the main piers also made satisfactory progress, and the masonry proceeded so rapidly that stones could scarcely be got from the quarries in sufficient quantity to keep the builders at work.  By the end of June about three hundred men were employed.
 

    The two principal piers, each 153 feet in height, upon which the main chains of the bridge were to be suspended, were built with great care and under rigorous inspection.  In these, as indeed in most of the masonry of the bridge, Mr. Telford adopted the same practice which he had employed in his previous bridge structures, that of leaving large void spaces, commencing above high water mark and continuing them up perpendicularly nearly to the level of the roadway.  "I have elsewhere expressed my conviction," he says, when referring to the mode of constructing these piers, "that one of the most important improvements which I have been able to introduce into masonry consists in the preference of cross-walls to rubble, in the structure of a pier, or any other edifice requiring strength.  Every stone and joint in such walls is open to inspection in the progress of the work, and even afterwards, if necessary; but a solid filling of rubble conceals itself, and may be little better than a heap of rubbish confined by side walls."  The walls of these main piers were built from within as well as from without all the way up, and the inside was as carefully and closely cemented with mortar as the external face.  Thus the whole pier was bound firmly together, and the utmost strength given, while the weight of the superstructure upon the lower parts of the work was reduced to a minimum.

    Over the main piers, the small arches intended for the roadways were constructed, each being 15 feet to the springing of the arch, and 9 feet wide.  Upon these arches the masonry was carried upwards, in a tapering form, to a height of 53 feet above the level of the road.  As these piers were to carry the immense weight of the suspension chains, great pains were taken with their construction, and all the stones, from top to bottom, were firmly bound together with iron dowels to prevent the possibility of their being separated or bulged by the immense pressure they had to withstand.

    The most important point in the execution of the details of the bridge, where the engineer had no past experience to guide him, was in the designing and fixing of the wrought iron work.  Mr. Telford had continued his experiments as to the tenacity of bar iron, until he had obtained several hundred distinct tests; and at length, after the most mature deliberation, the patterns and dimensions were finally arranged by him, and the contract for the manufacture of the whole was let to Mr. Hazeldean, of Shrewsbury, in the year 1820.  The iron was to be of the best Shropshire, drawn at Upton forge, and finished and proved at the works, under the inspection of a person appointed by the engineer.

 


    The mode by which the land ends of these enormous suspension chains were rooted to the solid ground on either side of the Strait, was remarkably ingenious and effective.  Three oblique tunnels were made by blasting the rock on the Anglesea side; they were each about six feet in diameter, the excavations being carried down an inclined plane to the depth of about twenty yards.  A considerable width of rock lay between each tunnel, but at the bottom they were all united by a connecting horizontal avenue or cavern, sufficiently capacious to enable the workmen to fix the strong iron frames, composed principally of thick flat cast iron plates, which were engrafted deeply into the rock, and strongly bound together by the iron work passing along the horizontal avenue; so that, if the iron held, the chains could only yield by tearing up the whole mass of solid rock under which they were thus firmly bound.

    A similar method of anchoring the main chains was adopted on the Caernarvonshire side. A thick bank of earth had there to be cut through, and a solid mass of masonry built in its place, the rock being situated at a greater distance from the main pier; involving a greater length of suspending chain, and a disproportion in the catenary or chord line on that side of the bridge.  The excavation and masonry thereby rendered necessary proved a work of vast labour, and its execution occupied a considerable time; but by the beginning of the year 1825 the suspension pyramids, the land piers and arches, and the rock tunnels, had all been completed, and the main chains were firmly secured in them; the work being sufficiently advanced to enable the suspending of the chains to be proceeded with.  This was by far the most difficult and anxious part of the undertaking.

    With the same careful forethought and provision for every contingency which had distinguished the engineer's procedure in the course of the work, he had made frequent experiments to ascertain the actual power which would be required to raise the main chains to their proper curvature.  A valley lay convenient for the purpose, a little to the west of the bridge on the Anglesea side.  Fifty-seven of the intended vertical suspending rods, each nearly ten feet long and an inch square, having been fastened together, a piece of chain was attached to one end to make the chord line 570 feet in length; and experiments having been made and comparisons drawn, Mr. Telford ascertained that the absolute weight of one of the main chains of the bridge between the points of suspension was 23½ tons, requiring a strain of 39½ tons to raise it to its proper curvature.  On this calculation the necessary apparatus required for the hoisting was prepared.  The mode of action finally determined on for lifting the main chains, and fixing them into their places, was to build the central portion of each upon a raft 450 feet long and 6 feet wide, then to float it to the site of the bridge, and lift it into its place by capstans and proper tackle.

    At length all was ready for hoisting the first great chain, and about the middle of April, 1825, Mr. Telford left London for Bangor to superintend the operations.  An immense assemblage collected to witness the sight; greater in number than any that had been collected in the same place since the men of Anglesea, in their war-paint, rushing down to the beach, had shrieked defiance across the Straits at their Roman invaders on the Caernarvon shore.  Numerous boats arrayed in gay colours glided along the waters; the day—the 26th of April—being bright, calm, and in every way propitious.

    At half-past two, about an hour before high water, the raft bearing the main chain was cast off from near Treborth Mill, on the Caernarvon side.  Towed by four boats, it began gradually to move from the shore, and with the assistance of the tide, which caught it at its further end, it swung slowly and majestically round to its position between the main piers, where it was moored.  One end of the chain was then bolted to that which hung down the face of the Caernarvon pier; whilst the other was attached to ropes connected with strong capstans fixed on the Anglesea side, the ropes passing by means of blocks over the top of the pyramid of the Anglesea pier.  The capstans for hauling in the ropes bearing the main chain, were two in number, manned by about 150 labourers.  When all was ready, the signal was given to "Go along!"  A band of fifers struck up a lively tune; the capstans were instantly in motion, and the men stepped round in a steady trot.  All went well.  The ropes gradually coiled in.  As the strain increased, the pace slackened a little; but "Heave away, now she comes!" was sung out.  Round went the men, and steadily and safely rose the ponderous chain.

 


    The tide had by this time turned, and bearing upon the side of the raft, now getting freer of its load, the current floated it away from under the middle of the chain still resting on it, and it swung easily off into the water.  Until this moment a breathless silence pervaded the watching multitude; and nothing was heard among the working party on the Anglesea side but the steady tramp of the men at the capstans, the shrill music of the fife, and the occasional order to "Hold on!" or "Go along!"  But no sooner was the raft seen floating away, and the great chain safely swinging in the air, than a tremendous cheer burst forth along both sides of the Straits.

    The rest of the work was only a matter of time.  The most anxious moment had passed.  In an hour and thirty-five minutes after the commencement of the hoisting, the chain was raised to its proper curvature, and fastened to the land portion of it which had been previously placed over the top of the Anglesea pyramid.  Mr. Telford ascended to the point of fastening, and satisfied himself that a continuous and safe connection had been formed from the Caernarvon fastening on the rock to that on Anglesea.

    The announcement of the fact was followed by loud and prolonged cheering from the workmen, echoed by the spectators, and extending along the Straits on both sides, until it seemed to die away along the shores in the distance.  Three foolhardy workmen, excited by the day's proceedings, had the temerity to scramble along the upper surface of the chain—which was only nine inches wide and formed a curvature of 590 feet—from one side of the Strait to the other! [p.342]

    Far different were the feelings of the engineer who had planned this magnificent work.  Its failure had been predicted; and, like Brindley's Barton Viaduct, it had been freely spoken of as a "castle in the air."  Telford had, it is true, most carefully tested every part by repeated experiment, and so conclusively proved the sufficiency of the iron chains to bear the immense weight they would have to support, that he was thoroughly convinced as to the soundness of his principles of construction, and satisfied that, if rightly manufactured and properly put together, the chains would hold, and that the piers would sustain them.  Still there was necessarily an element of uncertainty in the undertaking.  It was the largest structure of the kind that had ever been attempted.  There was the contingency of a flaw in the iron; some possible stamping in the manufacture; some little point which, in the multiplicity of details to be attended to, he might have overlooked, or which his subordinates might have neglected.  It was, indeed, impossible but that he should feel intensely anxious as to the result of the day's operations.  Mr. Telford afterwards stated to a friend, only a few months before his death, that for some time previous to the opening of the bridge, his anxiety was so great that he could scarcely sleep; and that a continuance of that condition must have very soon completely undermined his health.  We are not, therefore, surprised to learn that when his friends rushed to congratulate him on the result of the first day's experiment, which decisively proved the strength and solidity of the bridge, they should have found the engineer on his knees engaged in prayer.  A vast load had been taken off his mind; the perilous enterprise of the day had been accomplished without loss of life; and his spontaneous act was thankfulness and gratitude.

 

Modelled on Telford's abortive Runcorn Suspension Bridge across the Mersey, the Menai Suspension Bridge is seen here from the Anglesey bank across the notorious 'Swellies', and from a point near to Robert Stephenson's Britannia Bridge. The Menai Bridge's decking and suspension members have been rebuilt substantially over the years (e.g. compare bearing rods with those in Percival Skelton's illustration below) to address wear and to cater for an increasing traffic load, since relieved by the brilliant rebuilding of Stephenson's bridge.

Picture Wikipedia.


    The suspension of the remaining fifteen chains was accomplished without difficulty.  The last was raised and fixed on the 9th of July, 1825, when the entire line was completed.  On fixing a final bolt, a band of music descended from the top of the suspension pier on the Anglesea side to a scaffolding erected over the centre of the curved part of the chains, and played the National Anthem amidst the cheering of many thousand persons assembled along the shores of the Strait: while the workmen marched in procession along the bridge, on which a temporary platform had been laid, and the 'St. David' steam-packet of Chester passed under the chains towards the Smithy Rocks and back again, thus re-opening the navigation of the Strait.

 


    In August the road platform was commenced, and in September the trussed bearing bars were all suspended.  The road was constructed of timber in a substantial manner, the planking being spiked together, with layers of patent felt between the planks, and the carriage way being protected by oak guards placed seven feet and a half apart.  Side railings were added; the toll-houses and approach-roads were completed by the end of the year; and the bridge was opened for public traffic on Monday, the 30th of January, 1826, when the London and Holyhead mail coach passed over it for the first time, followed by the Commissioners of the Holyhead roads, the engineer, several stagecoaches, and a multitude of private persons too numerous to mention.

    We may briefly add a few facts as to the quantities of materials used, and the dimensions of this remarkable structure.  The total weight of iron was 2,187 tons, in 33,265 pieces.  The total length of the bridge is 1,710 feet, or nearly a third of a mile; the distance between the points of suspension of the main bridge being 579 feet.  The total sum expended by Government in its erection, including the embankment and about half a mile of new line of road on the Caernarvon side, together with the toll-houses, was £120,000.

 

Menai Suspension Bridge in the evening.  Picture Wikipedia.
 

Postcard showing an earlier view.  As built, the Bridge had three main suspensions chains.


    Notwithstanding the wonders of the Britannia Bridge subsequently erected by Robert Stephenson for the passage across the same strait of the Chester and Holyhead Railway, the Menai Bridge of Telford is by far the most picturesque object.  "Seen as I approached it," says Mr. Roscoe, "in the clear light of an autumnal sunset, which threw an autumnal splendour on the wide range of hills beyond, and the sweep of richly variegated groves and plantations which covered their base—the bright sun, the rocky picturesque foreground, villas, spires, and towers here and there enlivening the prospect—the Menai Bridge appeared more like the work of some great magician than the mere result of man's skill and industry,"

 


    Shortly after the Menai Bridge was begun, it was determined by the Commissioners of the Holyhead road that a bridge of similar design should be built over the estuary of the Conway, immediately opposite the old castle at that place, and which had formerly been crossed by an open ferry boat.  The first stone was laid on the 3rd of April, 1822, and the works having proceeded satisfactorily, the bridge and embankment approaching it were completed by the summer of 1826.  But the operations being of the same kind as those connected with the larger structure above described, though of a much less difficult character, it is unnecessary to enter into any details as to the several stages of its construction.  In this bridge the width between the centres of the supporting towers is 327 feet, and the height of the under side of the roadway above high water of spring tides only 15 feet.  The heaviest work was an embankment as its eastern approach, 2,015 feet in length and about 300 feet in width at its highest part.

    It will be seen, from the view of the bridge given on the opposite page, that it is a highly picturesque structure, and combines, with the estuary which it crosses, and the ancient castle of Conway, in forming a landscape that is rarely equalled.


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