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Table of the public roads of England, their length, and the cost of repairing them.
Years ending in October. Public Carriage Roads in England.
1812. 1813. 1814.
- Miles. Miles. Miles. Paved Streets and Turnpike Roads 19,114 19,132, 19,178 Other Roads . - - - 95,105 95,1424 95,184 Total length . - 114,219 114,275 114,362 Contributions in labor f515,508 539,522 551,241 Contributions in money 271,512 276,947 287,059 Taxes levied for the roads . 570,754 613,604 621,512 Total . . . . . fl,357,774 | 1,430,073 | 1,459,812 Expense of preparing documents, &c. 21,499 26,252 25,700
This gives us £12 7s.6d. for the average annual expense of maintaining each mile of open road. In this calculation I have deducted,' says our author, ‘from the total amount of the expense of road labor, the three days' labor which is allowed for turnpike roads; while six are allowed for open parish roads. “According to a report made to the house of commons on the 10th of June, 1821, the total amount of the sums levied in a single year on turnpike roads amounts to £970,618. This gives the average value of £47 18s. for the support of each mile of paved street and turnpike road. By adding the contributions in labor, the expense will amount to about £51 per mile. This revenue, immense as it is, is not sufficient for the construction of new roads, and the support of those that are already established. The different trusts have contracted debts, for which the rentals of each county are responsible. The total amount of the debts, at the period of the enquiry of which the report to which we have above alluded gives the result, was £3,874,254, that is to say, that these debts then equalled four years' revenue. It is affirmed that if the same calculation were made for Wales, Scotland, and Ireland, the general amount of the debt of the turnpike roads would amount to £7,000,000 sterling.'—vol. i. p. 86. The fact is that our modern improvements have been introduced in despite of a bad system —and, in their most decided feature, the simple methods of Mr. M'Adam exhibit the triumph of real genius and intelligence over cumbrous contrivances to make bad roads—and unmake good ones, that surveyors and inspectors may be paid. 1. Of the purposes of roads and of laying down the line—Roads, rivers, and canals have been called the veins and arteries of a country; all its other improvements flow and circulate by
means of them. Our legal system respecting them dates from the reign of Charles II., but it was not until the middle of the last century that scientific enquiry was directed toward them. Before carriages of burden were generally used, little more was required than a hard horse path. All marshy grounds were therefore shunned, and the inequality or circuit of the road was of much less consequence than, when carriages, instead of pack-horses, began to be employed. When carriages were first employed, they probably were light and narrow, and did not require to have roads of any considerable breadth. And, when these had once been traced, indolence and habit prevented any great exer. tions to lay them out in better lines. Heavier carriages and greater traffic made wider and stronger roads necessary; the ancient track was pursued; ignorance and want of concert in the proprietors of the ground, and, above all, the want of some general effective superintending power, continued this wretched practice. At length turnpikes were established, and laws passed investing magistrates with authority to alter established lines, so that now the chief obstacle to the improvement of the lines of public roads is the expense. In laying out roads, observes Mr. Loudon, a variety of circumstances require to be taken into consideration; but the principal are evidently their line or direction, and its inclination to the horizon. The most perfect line, according to Marshall, is that which is straight and level. But this is to be drawn in a country only which is perfectly flat, and where no obstructions lie in the way: joint circumstances that rarely happen. Where the face of the country, between two points or places to be connected by a road, is nearly but not quite level, by reason of gentle swells which rise between them, a straight line may be perfect, may be the most eligible, under these circumstances. But where the intervening country is broken into hill and dale, or if one ridge of hill only intervenes, a straight line of carriage road is seldom compatible with perfection. In this case, which is nearly general, the best skill of the surveyor lies in tracing the midway between the straight and the level line. The line of perfection, for agricultural
purposes, is to be calculated, by the time and exertion, jointly considered, which are required to convey a given burden, with a given power of draught, from station to station. On great public loads, where expedition is a Fo object, time alone may be taken as a good criterion. A regular method of finding out the true line of road between two stations, where a blank is given, where there is no other obstruction than what the surface of the ground to be got over presents, is to ascertain, and mark at proper distances, the straight line; which is the only certain guide to the surveyor. If the straight line be found to be ineligible, each mark becomes a rallying point, in searching on either side of it for a better. If two lines of equal facility, and nearly of equal distance from the straight line, present themselves, accurate measurements are to determine the choice. If one of the two best lines which the intervening country affords is found to be easier, the other shorter, the ascent and the distance are to be jointly considered ; the exertion and the time required are to be duly weighed. That part of a road which is coated with stones is called the ‘metalled part. Although in some places, Paterson observes, it may be of little consequence, either to the traveller, or to the public in general, which way the bendings are turned, provided the level is nearly obtained, —yet a great deal may depend upon those turns or bendings for the real benefit and advantage of the road. In bending it one way, you may have no metals that will stand any fatigue, unless at a great distance and expense; while, in turning it the other way, you may have metals of the very best quality, in the immediate vicinity. In the one way, too, you may be led over ground of a wet bottom, where even, with twelve or fourteen inches deep of metals, there would be difficulty in o: a good road; while, in the other, you may have such a dry bottom that the road would be much easier upheld with seven or eight inches of metals. So that the tract that may appear most eligible to the eye, at first sight, may not always be the one that should be adopted. “A combination of all the requisites I have already mentioned should be studied, as far as possible; and, where these cannot be found al to unite, the one possessing the most of these advantages, and subject to no other material objection, should, of course, be adopted.’ Treatise on Roads, p. 10. Roads, Edgeworth observes, should be laid out, as nearly as may be, in a straight line; but to follow with this view the mathematical axiom, that a straight line is the shortest that can be drawn between two points, will not succeed in making the most commodious roads; hills must be avoided, towns must be resorted to, and the sudden bends of rivers must be shunned. All these circumstances must be attended to; therefore a perfectly straight road cannot often be found of any great length. It may perhaps appear surprising that there is but little difference in the length between a road that has a gentle bend, and one that is in a perfectly straight line. A road ten miles long, and perfectly straight, can scarcely be found any where,
but if such a road could be found, and if it were curved, so as to prevent the eye from seeing further than a quarter of a mile of it, in any one place, the whole road would not be lengthened more than 150 yards. It is not proposed to make serpentine roads merely for the entertainment of travellers; but it is intended to point out, that a strict adherence to a straight line is of much less consequence than is usually supposed; and that it will be frequently advantageous to deviate from the direct line, to avoid inequalities of ground. It is obvious that, where the arc described by a road going over a hill is greater than that which is described by going round it, the circuit is preferable; but it is not known to every overseer that within certain limits it will be less laborious to go round the hill, though the circuit should be much greater than that which would be made in crossing the hill. Where a hill has an ascent of no more than one foot in thirty, the thirtieth part of the whole weight of the carriage, of the load, and of the horses, must be lifted up, whilst they advance thirty feet. In doing this, one-thirtieth part of the whole load continually resists the horses' draught; and, in drawing a waggon of six tons weight, a resistance equal to the usual force of two horses must be exerted. A perfectly level road, it has been often said, is not the best for every species of draught. Slight and short alternations of rising and falling ground are serviceable to horses moving swiftly; the horses have time to rest their lungs, and different muscles: and of this experienced drivers know well how to take advantage. Marshal concurs in this opinion, as well as Walker, Telford, and most engineers; and Paterson considers that it would not be proper to line a road upon a perfect level, even to the length of one mile together, although it could be quite easily obtained. It is a fact, he says, well known to most people, at least every driver of loaded carriages knows by experience, that where a horse, dragging a load over a long stretch of road, quite level, will be exhausted with fatigue; the same length of a road, having here a gentle acclivity, and there a declivity, will not fatigue the animal so much. This is easily accounted for. On a road quite level the draught is always the same, without any relaxation; but, on a gentle ascent, one of his powers is called into exercise; on the descent, another of his powers is called into action, and he rests from the exercise of the former. Thus are his different muscular powers moderately exercised, one after another; and this variety has not the same tendency to fatigue. Cutting through low hills to obtain a level is recommended by some, who, as Paterson observes, will argue ‘that where the hill of ascent is not very long it is better, in that case, to cut through it in a straight line, and embank over the hollow ground on each side, than to wind along the foot of it. This, however, should only be done where the cutting is very little indeed, and an embankment absolutely necessary. Few people, except those who are well acquainted, are aware of the great expense of cutting and embanking; and, the more any one becomes acquainted with road-making, the more,
it may be presumed, will he endeavour to avoid those lèvels on the straight line that are obtained only by cutting and embanking, and will either follow the level or the curved line round the hill; or, where this is impracticable, will ascend the hill, and go over it by various windings, avoiding always abrupt or sudden turnings.” Treatise, &c. p. 15. According to Walker, Minutes of Evidence oefore a Committee of the House of Commons, 1819, a dry foundation and clearing the road from water are two of the main objects. ‘For obtaining the first of these objects it is essential that the line for the road be taken so that the foundation can be kept dry, either by avoidin low ground, by raising the surface of the roa above the level of the ground on each side of it, or by drawing off the water by means of side drains. The other object, viz. that of clearing the road of water, is best secured by selecting a course for the road which is not horizontally level, so that the surface of the road may in its longitudinal section form in some degree an inclined plane; and when this cannot be obtained, owing to the extreme flatness of the country, an artificial inclination may generally be made. When a road is so formed, every wheel track that is made, being in the line of the inclination, becomes a channel for carrying off the water, much more effectually than can be done by a curvature in the cross section or rise in the middle of the road, without the danger, or other disadvantages, which necessarily attend the rounding a road much in the middle. I consider a fall of about one inch and a half in ten feet to be a minimum in this case, if it is attainable without a great deal of extra expense.” The ascent of hills, as observed by Marshal, is of course one of the most difficult parts of laying out roads. According to theory, he says, an inclined plane of easy ascent is proper; but as the moving power on this plane is “neither purely mechanical, nor in a sufficient degree rational, but an irregular compound of these two qualities, the nature and habits of this power' require a varied inclined plane, or one not a uniform descent, but with levels or other proper places for rests. According to the road act the ascent or descent should not exceed the rate or proportion of one foot in height to thirty-five feet of the length thereof, if the same be practicable, without causing a great increase of distance. Mr. Telford, Minutes before the Committee of the House of Commons, &c., 1819, referring to those which he has lately made through the most difficult and precipitous districts of North Wales, says, “the longitudinal inclinations are in general less than one in thirty; in one instance for a considerable distance there was no avoiding one in twenty-two, and in another, for about 200 yards, one in seventeen; but, in these two cases, the surface of the road-way being made peculiarly smooth and hard, no inconvenience is experienced b wheeled carriages. On flat ground the to: of the road-way is thirty-two feet; where there is side cutting not exceeding three feet, the breadth is twenty-eight; and, along any steep ground and precipices, it is twenty-two, all
clear within the fences; the sides are protected by stone walls, breast and retaining walls, and parapets; great pains have been bestowed on the cross drains, also the draining the ground, and likewise in constructing firm and substantial foundations for the metalled part of the roadway.” In order to preserve a moderate inclination, or such a one as will admit of the descent of carriages without locking their wheels, a much longer line will generally be required than the arc of a hill. In reaching the summit, or highest part to be passed over, the line in many cases must be extended by winding or zigzagging it, so as never to exceed the maximum degree of steepness. Two inches in six feet is the slope of the celebrated Simplon road. If this were extended in a straight line, on each side, it would require an enormous mound, and an immense expense; but by being conducted in a winding direction, up the hill on one side, and down the other, the same end is gained at a moderate cost. Such works show the wonderful power and ingenuity of man. In laying out a road towards a river, or any place requiring a bridge or embankment, an obvious advantage results from approaching them at right angles; and the same will apply in regard to any part requiring tunnelling or crossing by an aqueduct, &c.; all crossings and intersections should indeed be made at right angles. 2. Of the width and form of roads—It is contended, by the author of the Landed Property of England, that the plan of all public roads should admit of their being divided into three travellable lines, namely: 1. A middle road of hard materials for carriages and horses in winter and wet seasons: 2. A soft road, formed with the natural materials of the site, to be used in o weather, to save the unnecessary wear of the hard road, and to favor the feet of travelling animals; as well as for the safety, ease, and pleasantness of travelling in the summer season: and 3. A commodious path, for the use of foot passengers, at all seasons. But in these cases, he thinks, modern practice has simplified too much. Instead of these three requisites of a public road, we generally find a parliamentary or turnpike road (away from the environs of great towns) consisting simply of one uniform broadway of hard materials; upon which horses stumble, and carriages jolt, the year round: while travellers on foot are seen wading to their ankles in mud, or in dust, according to the state of the wind and weather. His notions of what the nature of a public road ought to be is, that within the fences of a lane or road there should be a raised foot-path, a convex hard road, a soft summer road, and channels to carry off the water collected by the carriage roads; the foot-path being cut across in
proper places, to permit the water, which falls
on that side of the middle road, to pass off freely into the ditch at that side, as well as to prevent horsemen from riding along the path; the opposite hedge-bank being perforated, to let off, into the other drain on the contrary side, the waters which may collect on that side of the lane or road. Mr. Telford, Mr. Walker, and most other engineers, consider seventy feet a sufficient
feet of gravel road at each side for light carriages or horses. It has been executed for sixteen years, and has given the greatest satisfaction; but Mr. Walker thinks that considerable improvement would be found from paving the sides of a road, upon which the heavy traffic is great, in both directions, and leaving the middle for light carriages; the carmen or drivers, walking upon the foot-paths or sides of the road, would then be close to their horses, without interrupting or being in danger of accidents from light carriages, which is the case when they are driving upon the middle of the road; and the unpaved part, being in the middle or highest part of the road, would be more easily kept in good repair. But unless the heavy traffic in both directions is great, one width, say ten or twelve feet, in the middle of the road, well paved, will be found sufficient for all ordinary wear. The width of many of the present roads is, besides, such, that ten or twelve feet can be spared for paving, while twice that width would leave too little for the gravelled part. Although the first cost of paving is great he does not think that any other plan can be adopted so good and so cheap in those places where the materials got in the neighbourhood are not sufficient for supporting the roads. A coating of whinstone is, for instance, more durable than the gravel with which the roads round London are made and repaired; but much less so than paving; although the freight and carriage of the whinstone, and of the paving-stones, which form the principal items of the expense, are nearly the same. Proportioning the breadth of roads to the traffic for which they may be employed, has, perhaps, not been sufficiently attended to. In remote places, where there is but little traffic, the waste of ground occasioned by superfluous
width of roads, is an error: there being many
places where roads of twenty feet breadth would suit the public convenience, as well as if they were twice as broad; and it is clear that, if a road is one pole or perch wider than is necessary, there is a waste of 320 perches in a mile, equal to two acres of ground, which, at the rate of £3 per acre, would, if the road had been once well made, keep half a mile of such road as is here alluded to in good repair. According to Paterson, the breadth of the road and the width of the metals, or paved part, should depend on circumstances different from the former. For a few miles in the vicinity of such cities as London or Edinburgh, the most proper breadth at which a road should be formed, he thinks, is from sixty to seventy feet, and the metals from twenty-five to thirty-five feet; while, in the neighbourhood of such towns as Newcastle and Perth, it will be sufficient that it be formed forty feet broad, and that the width of the metals be about eighteen or twenty feet. These are the breadths presumed to be the most eligible in such situations. But rules cannot be given to suit every situation: the breadth ought to be regulated according to the
extent of the run of commerce, or traffic, upon the road. As a general rule however, for public roads over the different counties of Great Britain, I should suppose, he says, the following might in most cases be adopted. Take for instance the road betwixt Fidinburgh and Glasgow. or betwixt Fdinburgh and Aberdeen, by the way of Dundee. These roads are formed in general from thirty-five to forty feet wide; and the breadth of the metals is from fourteen to sixteen feet for the most part. Such roads as these would be found to answer very well, in general, over the kingdon. A breadth sufficient for the general purposes of country travelling, according to M'Adam, is sixteen feet of solid materials, with six feet on each side formed of slighter materials. The Bristol roads, he says, are made with stome about the width of sixteen feet. Narrow roads, it is well observed by Fry, are almost always in bad condition, which is to be accounted for from the circumstance of every carriage being obliged to go in the same ruts; and, as each rut is generally only six inches wide, one foot of the road only is worn by the wheels instead of the whole breadth of it; which would be the case if the road were of a proper width, and if it were well constructed. If a road be laid out from twenty to thirty feet wide, so flat as that a carriage may stand nearly upright on every part of it, and if moderate care be taken by the surveyor to prevent the first formation of ruts, such a road will be worn by the wheels nearly alike on every part of it: provided also that the ground on each side, for at least four or five feet, be moderately flat, so as not to excite fear in the drivers of o but if there be deep ditches close to the sides of the road, or if the circumjacent land fall off very abruptly to the depth of two or three feet, whereby fear of approaching the edges would operate on the minds of the drivers, every driver will instinctively avoid the danger on either hand; and a road so circumstanced will, in spite of any care of the surveyor, inevitably be worn into ruts in the middle. There is a remarkable instance of this kind in a piece of road on Durdham Down, near Bristol. This road is a causeway over a piece of soft ground; and, although it is from twenty to twenty-five feet wide, yet, as the ground falls away abruptly on both sides of it, it has been found impossible, for more than twenty years past, to his knowledge, to prevent deep ruts being formed along the middle of it; notwithstanding the Down itself consists of hard limestone; and the other roads upon the Down are as fine and even as any roads in England. Were this piece of road widened out on each side, in an easy slope about five eet, by rubbish of any kind, and by the scrapings of the load itself, whereby the instinctive operation of fear of approaching the sides of the present road would be obviated, that piece of road would be found to wear as fairly as the other roads on the same Down. When roads run through marshy ground, observes Mr. Edgeworth, “the substratum must be laid dry by proper drainage; and where the road is liable, from the flatness of the country, to be at times under water, the expense of raising it above the water must be submitted to in the first instance. All drains for carrying off water should be under the road, or at the field side of the fences, and these drains should be kept open by constant attention, and should be made wide at the outlet.’ Telford and Walker recommend the side drains to be in every instance on the field side of the fence. In cases, Telford observes, where a road is made upon ground where there are many springs, it is absolutely necessary to make a number of under and cross drains to collect the water and conduct it into the side drains, which should always be made on the field side of the fences. The orifices of these cross drains should be neatly and substantially finished in masonry. “Before the materials are put on, run a drain along the middle of the road, all the way, from two to three feet deep; then fill it with stones up to the surface, making those at bottom of a pretty good size, and those at the top full as small as the road materials. And, in order that the quantity of stones used for the said drain may be as little as possible, and every way to save expense, it may be made as narrow as it can possibly be dug. From this leading drain make a branch here and there to convey off the water to the canals on the sides of the road.'—Paterson. This mode of draining he has found from experience to be so beneficial that a road so drained would be better and more durable with eight inches, than it would otherwise be with twelve inches of materials. And not only so, but that on such a road there would be a saving on the incidental repairs, ever afterwards, of about one-half of the labor, and at least onethird of the material. “All moisture from under, the road materials should be carried off by such drains. Where such drains are wanting, the road, on the return of a thaw, throws up to the surface all the water it had imbibed; and in many places the materials, swelling up, become quite loosa and open. This is a natural consequence, where the material is not thick, and where the soil under the road is not perfectly dry. But, where a road is dried in the way described, it will be uniformly seen that the water, instead of spewing out on the return of a thaw, is sucked in by the drains, so leaving the surface of the road quite dry. It may be observed, at such times, that the places of the road where a few roods of such drain had been introduced, presented to the eye, at a quarter of a mile distance, quite a contrast to the other parts of the road; the one opaque and dry, from the moisture being sucked in, the other all wet and glistering, from its being thrown out to the surface.”—Paterson's Letters, &c., 44, 48, 84. Embankments and bridges of different degrees of magnitude, are required in most lines of road. Large bridges we must leave to engineers; no department of their art having attained higher perfection. We here confine ourselves entirely to such stone arches as may be designed by road-surveyors, and built by country masons. In many cases cast-iron might be substituted for stone with economy and advantage as to waterway; but, though the principle of constructing both cast and wrought iron bridges is perfectly simple, the execution, and especially the putting up, requires more skill, and is attended with
much more risk than the erection of other bridges, One low arch is thought by Mr. Loudon to be in general the most desirable description of common road-bridges. But most of the country bridges, as Clarke observes, consist of several small, high, semicircular arches: where there is a single arch, the stream passes without interruption; if there are two or three in the same situation, the space through which the water is to pass is necessarily contraoted by the width of piers. Ice, and large bodies carried down by the floods, frequently stop up the small arches, and the ...} water carries away the bridge; but, if such accidents should not happen, the constant currents rushing against those piers wash out the mortar, loosen the stones, and very soon undermine the work if it is not extremely well put together, which is seldom the case. Unless the river or stream is narrow, or the banks very high, a semicircle is an inconvenient shape for an arch ; it has been adopted on account of the insufficiency of the abutments, and because the pressure is more perpendicular; but scientific engineers, in all countries, now construct their bridges with wide openings, and make the arches either semi-ellipses, or segments of large circles; so that the space above the highest floods is comparatively little, and the ascent over the bridge inconsiderable. In country bridges in Ireland, Clarke continues, the foundations are invariably, and often intentionally, defective: the mason considers himself an honest man if his bridge lasts seven years; whereas, from the durability of materials in that country, it ought to endure for ages. Whatever is under water is out of sight, and is generally composed of loose stones, thrown promiscuously together, on which the masonry is erected, and all the pains and expense are bestowed on the cutwaters and wings, when the heaviest stones, and those accurately jointed, ought to be laid in the foundations. e greatest attention should be paid to the quality of the materials: the stones should be large, and laid in level courses, in the best mortar, composed of sharp sand, free from loam, and quicklime, accurately mixed together; the coping of the parapet is generally so slight that it is broken down as soon as built, and the entire parapet quickly follows; it ought to be of large heavy stones, roughly hammered, and there should be substantial quoins at the ends of the parapets with an immovable stone over them. Arches not exceeding eight feet span may be semicircular; tunnels not exceeding eighteen inches wide may be covered with strong flags, and either flagged or paved under, and there ought to be across either end a deep long stone, sunk below the surface of the current, and under the walls, to prevent the water from undermining the work. Fences along the sides of roads are essential in all enclosed conntries; and all engineers and road-makers agree that they should never be allowed to rise to a greater height than what is necessary for a fence. To give free admission to the sun and air, by keeping the fences low, Marshall considers as providing an expensive, yet most accurate method of cleaning roads, incomparably more so than washing or scraping. The