A1-The Great North Road
Daniel Defoe was an enthusiastic promoter of investment to improve roads. Travelling up the Great North Road through Yorkshire, he had this advice for road builders, given in his A Tour Through the Whole Island of Great Britain of about 1725:
The Great Roman Highway...from Castleford Bridge...goes out to Abberforth... I mention it on this occasion,
1. That in some places this causeway being cut into and broken up, the eminent care of the Romans for making firm causeways for the convenience of carriage, and for the passing of travellers, is to be seen there. The layings of different sorts of earth, as clay at the bottom, chalk upon that, then gravel again; and so of other kinds of earth, where the first was not to be had.
2. In some places between this bridge and the town of Abberforth, the causeway having not been used for the ordinary road, it lies as far and untouched, the surface covered with turf, smooth as at its first making, not so much as the mark of a hoof or of a wheel upon it; so that it is to be seen in its full dimensions and height, as if it had been made the same week, whereas 'tis very probable it had stood so fifteen or sixteen hundred years; and I take notice of it here, because I have not seen any thing like it in any other place in England and because our people, who are now mending the roads everywhere, might take a pattern from it.
General George Wade, 1673-1748, was responsible for the construction of the 'military roads' in the Scottish Highlands, built between 1725 and 1734. Many of what were known as 'Wade's Roads' were actually built under the direction of William Caulfeild, who was appointed inspector of roads in 1732. Some 750 miles of the total of 1200 miles of military roads were built in Caulfeild's time between 1745 and 1767. Many of the roads were improvements on the pre-existing drove roads and all were without the benefit of the construction methods introduced at the end of the century by Telford and McAdam.
John Smeaton, 1724–92, English civil engineer. He became an instrument maker, improved navigation instruments, and carried out many experiments on mechanical apparatus. Between 1750 and 1755 his interests turned increasingly to engineering, as evidenced by a number of papers read before the Royal Society during this period. He rebuilt (1756–59) the Eddystone lighthouse and worked on the Forth and Clyde Canal, Ramsgate Harbour and many important bridges. Within 10 years he became recognized as the first fully professional engineer of his time. In 1770 he built the road viaduct at Newark and in 1776 the six-arched bridge over the Tweed at Coldstream.
John (Blind Jack) Metcalf was born in 1717 at Knaresborogh. He lost his sight in a small-pox attack when six years old but led a very active life. He was a good horseman, joined the army as a musician and ran a carrier business which involved a close acquaintance with the state of the roads, particularly in and around Yorkshire, plying the first stage waggon on the York to Knaresborough road. Metcalf's road-building career began when a contractor was required following the 1765 Turnpike Act for the Boroughbridge-Harrogate road. Over the next thirty years he was responsible for the reconstruction of many roads and associated bridges in Yorkshire, Lancashire and beyond. His notable achievements included building roads through boggy areas by pilling stones on top of brushwood foundations.
Here is a biography of Jack Metcalf
Thomas Telford was born in 1757 in an isolated part of Eskdale in south-west Scotland. His father, a shepherd, died when he was a few months only leaving his widowed mother destitute and, materially, about as poor as it comes. But with good neighbours in a caring community and an elementary education in the village school, Thomas's cheerful yet industrious personality won him friends and favours. Apprenticed as a stone mason, he had an unusual appetite for self education and improvement. His skillful craftsmanship, practiced on farm buildings and road bridges in his home valley, found good employment in the development of Edinburgh New Town. Here Telford learnt architectural drawing and increased his breadth of literary experience. After two years he moved to London and, employed as a stone mason, soon showed he was more than an exceptional craftsman but could be entrusted with project management. After two years in Portsmouth working on building projects for the Admiralty, he moved to Shropshire where he was appointed surveyor to the county, responsible for numerous bridge-building and other engineering projects. By the time he was 35 years old he had become engineer to the Elsemere Canal Company for whom he superintended much of the canal construction in the county for the rest of his life, the last being the Birmingham and Liverpool Union Canal, completed in 1835, a couple of years after his death.
But although based in Shropshire at first, Telford's engineering work took him to many other parts and he needed a base in London. For 21 years he rented an apartment at the Salopian Coffee House, near Charing Cross before eventually taking a house of his own, still in central London. He worked on improvements to the harbour facilities at several Scottish ports, the Caledonian Canal and a major canal in Sweden. Nine hundred miles of roads, including 1200 bridges, were built by Telford in the Scottish Highlands and, later in his career, he made major improvements to the Carlisle to Glasgow road and other roads in the Southern Scotland. Perhaps his best-remembered work, commemorated by the naming of the new town, Telford, in Shropshire, is his work on the Holyhead Road. This involved much new building in the Welsh section, including the Britannia Bridge over the Menai Strait to Anglesey, the largest suspension bridge of its time.
Throughout his life, Telford worked hard and strove towards engineering excellence and the respect of his fellows rather than earning a fortune. He lived modestly and when engaged in public works sometimes waived his fee . On his death he bequeathed a substantial sum to the Institute of Civil Engineers, of which he was president. He is buried in Westminster Abbey.
Telford's involvement with the Great North Road is here described by Smiles:
The reconstruction of the western road from Carlisle to Glasgow, which Telford had 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 per 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 Aukland 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 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.
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 endeavored 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.
John Loudon McAdam (1756 - 1836). In contrast to Telford's humble origins, born into poverty but earning a considerable fortune through a lifetime's work as an engineer, McAdam was born into a wealthy family that probably lost more money than it earned through his lifetime. His work on road construction began with experiments on private roads on the family estate. McAdam became a Road Trustee in his native Ayr in 1787, but it was not until 1801, at the age of 45, with his appointment as surveyor to the Bristol turnpike trustees that his road-building career was launched. By 1823, he was consulting surveyor to about 70 Road Trusts, 34 of which were managed by the McAdam family. In 1827 he became General Surveyor of Roads. His name lives on in Tar-McAdam or Tarmac, though he never used tar in his road building. Curiously, part of the family business in the 18th century had been based on production of tar used in shipbuilding.
In terms of road engineering, McAdam's essential insight is revealed in these paragraphs from his 1820 publication Remarks on the Present System of Road Making:
The roads can never be rendered thus perfectly secure until the following principles be fully understood, admitted and acted upon: namely, that it is the native soil which really supports the weight of traffic: that while it is preserved in a dry state, it will carry any weight without sinking, and that it does in fact carry the road and the carriages also; that this native soil must previously be made quite dry, and a covering impenetrable to rain must then be placed over it, to preserve it in that dry state; that the thickness of a road should only be regulated by the quantity of material necessary to form such impervious covering, and never by any reference to its own power of carrying weight.
The erroneous opinion so long acted upon and so tenaciously adhered to, that by placing a large quantity of stone under the roads, a remedy will be found for the sinking into wet clay, or other soft soils, or in other words, that a road may be made sufficiently strong artificially, to carry heavy carriages, though the subsoil be in a wet state, and by such means to avert the inconveniences of the natural soil receiving water from rain or other causes, has produced most of the defects of the roads of Great Britain.
Both Telford and McAdam understood the importance of good drainage, as did the Romans with their agger and road-side ditches. The both insisted that roads should be made with small broken stones which bind together rather than rounded pebbles and gravel which move with the passing of wheels. But while Telford used a foundation of larger material, McAdam argued that this was an unnecessary expense, a thick layer of crushed rock being stable and strong enough to support traffic even across boggy ground. McAdam's method tended to require more frequent, though relatively cheap, repairs, involving the spreading of a new layer of suitably graded broken stone. Telford's roads were long-lasting but there was the danger that larger material from below could work its way to the surface, necessitating costly repairs.
Here is a biography of McAdam, another.
One might take it for granted that a transverse slope of camber was a good thing, enabling the water to drain off quickly. Both Telford and McAdam used a camber with the road center some four to nine inches higher than the edges. Not so simple. To keep coaches upright, drivers used the centre of the road, wearing this area down to produce ruts and puddles in the middle, whereas with a flat or very gently sloping road, the whole carriageway is used and drainage just as good. Henry Law, writing in the 1850s, cites McAdam's evidence to Parliament in support of his argument.
The form to be given to the cross section of a road is a subject of much importance, and one upon which much difference or opinion exists. Some advocate a considerable curvature in the upper surface of the road, with the view of facilitating the drainage of its surface; while others (and that the majority) are averse to a road being much curved, for reasons which we ~l presently state. Again, it is the practice of some to form the road on a flat surface transversely; while others propose giving a dip to the formation surface each way from the center, on the sup position that the drainage of the road will be thereby facilitated.
Now it must be obvious to all, that the only advantage resulting from curving the transverse section of the road is, allowing the water, which would otherwise collect upon its surface, to drain freely off into the side ditches. It has been urged by some that, in laying on fresh material upon a road, it is necessary to keep the center much higher than the sides; because, in consequence of the majority of carriages using the center of the road, that portion will wear quicker than the sides, and, unless made originally much higher, when so worn it will necessarily form a hollow or depression, from which the water cannot drain. Sow it is entirely overlooked by those who advance this argument, that the only reason why carriages use the center in preference to the sides of a road, is because of its rounding fern:, it being only in that situation that the carriage stands upright; if the road were comparatively flat, every portion would be equally used; but on very convex roads, the center is the only portion of the road on which it is safe to travel. On this subject Mr. McAdam remarks, in giving evidence before a committee of the House of Commons, (Parliamentary Report on the Highways of the Kingdom, 1819, p22).
"I consider a road should be as flat as possible with regard to allowing the water to run off it at all, because a carriage ought to stand upright in travelling as much as possible. I have generally made roads three inches higher in the center than I have at the sides, when they are eighteen feet wide; if the road be smooth and well made, the water will run off very easily in such a slope." And, in answer to the question, "Do you consider a road so made will not be likely to wear hollow in the middle, so as to allow the water to stand, after it has been used for some time?" he replies,-" No; when a road is made flat, people will not follow the middle of it as they do when it is made extremely convex. Gentlemen will have observed that in roads very convex, travellers generally follow the track in the middle, which is the only place where a carriage can run upright, by which means three furrows are made by the horses and the wheels, and water continually stands there; and I think that more water actually stands upon a very convex road than on one which is reasonably flat."
Johnson notes McAdam's early involvement with roads before he worked in actual road construction. In 1804 the Cheshunt Trust resolved to cover the original stone inscription with the iron plate produced by Mr McAdam
Lincolnshire
©Biff Vernon 2002, 2003