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Table of the public roads of England, their length, and the cost of repairing them.
Thus it appears that the average annual ex means of them. Our legal system respecting penses of all the roads in England were, from them dates from the reign of Charles II., but it 1811 to 1814, as follows:
was not until the middle of the last century Contributions in labor
that scientific enquiry was directed toward them. Ditto in money
Before carriages of burden were generally Sums raised by rate
used, little more was required than a hard horse
path. All marshy grounds were therefore shun£1,415,883
ned, and the inequality or circuit of the road
was of much less consequence than when carThis gives us £12 7s.6d. for the average annual riages, instead of pack-horses, began to be emexpense of maintaining each mile of open road. ployed. When carriages were first employed, In this calculation I have deducted,' says our they probably were light and narrow, and did author, “from the total amount of the expense of not require to have roads of any considerable road labor, the three days' labor which is allowed breadth. And, when these had once been traced, for turnpike roads ; while six are allowed for indolence and habit prevented any great exeropen parish roads.
tions to lay them out in better lines. Heavier * According to a report made to the house of carriages and greater traffic made wider and commons on the 10th of June, 1821, the total stronger roads necessary; the ancient track was amount of the sums levied in a single year on pursued; ignorance and want of concert in the turnpike roads amounts to £970,618. This proprietors of the ground, and, above all, the gives the average value of £47 18s. for the sup- want of some general effective superintending port of each mile of paved street and turnpike power, continued this wretched practice. At road. By adding the contributions in labor, the length turnpikes were established, and laws expense will amount to about £51 per mile. passed investing magistrates with authority to This revenue, immense as it is, is not sufficient alter established lines, so that now the chief obfor the construction of new roads, and the sup- stacle to the improvement of the lines of public port of those that are already established. The roads is the expense. different trusts have contracted debts, for which In laying out roads, observes Mr. Loudon, a the rentals of each county are responsible. The variety of circumstances require to be taken into total amount of the debts, at the period of the consideration; but the principal are evidently enquiry of which the report to which we have their line or direction, and its inclination to the above alluded gives the result, was £3,874,254, horizon. The most perfect line, according to that is to say, that these debts then equalled four Marshall, is that which is straight and level. years' revenue. It is affirmed that if the same But this is to be drawn in a country only which calculation were made for Wales, Scotland, and is perfectly flat, and where no obstructions lie Ireland, the general amount of the debt of the in the way: joint circumstances that rarely hapturnpike roads would amount to £7,000,000 pen. Where the face of the country, between sterling.'-vol. i. p. 86.
two points or places to be connected by a road, The fact is that our modern improvements is nearly but not quite level, by reason of gentle bave been introduced in despite of a bad system swells which rise between them, a straight line -and, in their most decided feature, the simple may be perfect,--may be the most eligible, under methods of Mr. M'Adam exhibit the triumph of these circumstances. But where the interreal genius and intelligence over cumbrous con- vening country is broken into hill and dale, or trivances to make bad roads—and unmake good if one ridge of bill only intervenes, a straight ones, that surveyors and inspectors may be paid. line of carriage road is seldom compatible with
1. Of the purposes of roads and of laying perfection. In this case, which is nearly genedown the line.-Roads, rivers, and canals have ral, the best skill of the surveyor lies in tracing been called the veins and arteries of a country; the midway between the straight and the level all its other improvements flow and circulate by line. The line of perfection, for agricultural
purposes, is to be calculated, by the time and but if such a road could be found, and if it were exertion, jointly considered, which are required curved, so as to prevent the eye from seeing to convey a given burden, with a given power of further than a quarter of a mile of it, in any one draught, from station to station. On great public place, the whole road would not be lengthened 1oads, where expedition is a principal object, more than 150 yards. It is not proposed to time alone may be taken as a good criterion. make serpentine roads merely for the entertainA regular method of finding out the true line of ment of travellers ; but it is intended to point road between two stations, where a blank is out, that a trict adherence to a straight line is of given, where there is no other obstruction than much less consequence than is usually supwhat the surface of the ground to be got over posed; and that it will be frequently adranpresents, is to ascertain, and mark at proper dis tageous to deviate from the direct line, to avoid tances, the straight line; which is the only certain inequalities of ground. It is obvious that, guide to the surveyor. If the straight line be where the arc described by a road going over a found to be ineligible, each mark becomes a ral- hill is greater than that which is described by lying point, in searching on either side of it for going round it, the circuit is preferable; but it a better. If two lines of equal facility, and is not known to every overseer that within nearly of equal distance from the straight line, certain limits it will be less laborious to go round present themselves, accurate measurements are the hill, though the circuit should be much to determine the choice. If one of the two best greater than that which would be made in crosslines which the intervening country affords is ing the hill. Where a hill has an ascent of no found to be easier, the other shorter, the ascent more than one foot in thirty, the thirtieth part and the distance are to be jointly considered; of the whole weight of the carriage, of the lord, the exertion and the time required are to be duly and of the horses, must be lifted up, whilst they weighed.
advance thirty feet. In doing this, one-thirtieth That part of a road which is coated with part of the whole load continually resists the stones is called the metalled. part. Although horses' draught; and, in drawing a waggon of in some places, Paterson observes, it may be of six tons weight, a resistance equal to the usual little consequence, either to the traveller, or to force of two horses must be exerted. the public in general, which way the bendings A perfectly level road, it has been often said, are turned, provided the level is nearly obtained, is not the best for every species of draught. -yet a great deal may depend upon those turns Slight and short alternations of rising and fallor bendings for the real benefit and advantage ing ground are serviceable to horses moving of the road. In bending it one way, you may swiftly; the horses have time to rest their lungs have no metals that will stand any fatigue, un and different muscles : and of this experienced less at a great distance and expense; while, in drivers know well how to take advantage. Marturning it the other way, you may have metals of shal concurs in this opinion, as well as Walker, the very best quality, in the immediate vicinity. Telford, and most engineers; and Paterson conIn the one way, too, you may be led over siders that it would not be proper to line a road ground of a wet bottom, where even, with twelve upon a perfect level, even to the length of one mile or fourteen inches deep of metals, there would together, although it could be quite easily obbe difficulty in keeping a good road; while, in tained. It is a fact, he says, well known to the other, you may have such a dry bottom that most people, at least every driver of loaded car. the road would be much easier upheld with seven riages knows by experience, that where a horse, or eight inches of metals. So that the tract that dragging a load over a long stretch of road, quite may appear most eligible to the eye, at first level, will be exhausted with fatigue; the same sight, may not always be the one that should be length of a road, having here a gentle acclivity, adopted. A combination of all the requisites and there a declivity, will not fatigue the animal I have already mentioned should be studied, as so much. This is easily accounted for. Ona far as possible; and, where these cannot be road quite level the draught is always the same, found all to unite, the one possessing the most without any relaxation ; but, on a gentle ascent; of these advantages, and subject to no other ma one of his powers is called into exercise; on the terial objection, should, of course, be adopted.' descent, another of his powers is called into Treatise on Roads, p. 19.
action, and he rests from the exercise of the Roads, Edgeworth observes, should be laid former
. Thus are bis different muscular powers out, as nearly as may be, in a straight line; but moderately exercised, one after another; and to follow with this view the mathematical axiom, this variety has not the same tendency to fatigue. that a straight line is the shortest that can be Cutting through low bills to obtain a level is drawn between two points, will not succeed in recommended by some, who, as Paterson obmaking the most commodious roads; hills must serves, will argue that where the hill of ascent be avoided, towns must be resorted to, and the is not very long it is better, in that case, to cui sudden bends of rivers must be shunned. All through it in a straight line, and embank over these circumstances must be attended to; there. the hollow ground on each side, than to wind fore a perfectly straight road cannot often be along the foot of it. This, however, should found of many great length. It may perhaps only be done where the cutting is very little appear surprising that there is but little differ- indeed, and an embankment absolutely necesence in the length between a road that has sary. Few people, except those who are well gentle bend, and one that is in a perfectly acquainted, are aware of the great expense of straight line. A road ten miles long, and per- cutting and embanking; and, the more any one fectly straight, can scarcely be found any where, becomes acquainted with road-making, the more,
it may be presumed, will be endeavour to avoid clear within the fences; the sides are protected those levels on the straight line that are obtained by stone walls, breast and retaining walls, and only by cutting and embanking, and will either parapets ; great pains have been bestowed on follow the level or the curved line round the the cross drains, also the draining the ground, hill; or, where this is impracticable, will ascend and likewise in constructing firm and substantial the bill, and go over it by various windings, foundations for the metalled part of the roadavoiding always abrupt or sudden turnings.' way.' Treatise, &c. p. 15.
In order to preserve a moderate inclination, According to Walker, Minutes of Evidence or such a one as will admit of the descent of Defore a Committee of the House of Commons, carriages without locking their wheels, a much 1819, a dry foundation and clearing the road longer line will generally be required than the from water are two of the main objects. For arc of a hill. In reaching the summit, or highobtaining the first of these objects it is essential est part to be passed over, the line in many that the line for the road be taken so that the cases must be extended by winding or zigzagfoundation can be kept dry, either by avoiding ging it, so as never to exceed the maximum low ground, by raising the surface of the road degree of steepness. Two inches in six feet is above the level of the ground on each side of it, the slope of the celebrated Simplon road. If or by drawing off the water by means of side this were extended in a straight line, on each side, drains. The other object, viz. that of clearing it would require an enormous mound, and an the road of water, is best secured by selecting a immense expense; but by being conducted in a course for the road which is not horizontally winding direction, up the hill on one side, and level, so that the surface of the road may in its down the other, the same end is gained at a longitudinal section form in some degree an in- moderate cost. Such works show the wonderful clined plane; and when this cannot be obtained, power and ingenuity of man. owing to the extreme flatness of the country, an In laying out a road towards a river, or any artificial inclination may generally be made. place requiring a bridge or embankment, an obWhen a road is so formed, every wheel track vious advantage results from approaching them that is made, being in the line of the inclination, at right angles; and the same will apply in rebecomes a channel for carrying off the water, gard to any part requiring tunnelling or crossing much more effectually than can be done by á by an aqueduct, &c. : all crossings and interseccurvature in the cross section or rise in the tions should indeed be made at right angles. middle of the road, without the danger, or other 2. Of the width and form of roads.- It is condisadvantages, which necessarily attend the tended, by the author of the Landed Property of rounding a road much in the middle. I con- England, that the plan of all public roads should sider a fall of about one inch and a half in ten admit of their being divided into three travellable feet to be a minimum in this case, if it is attain- lines, namely: 1. Å middle road of hard mateable without a great deal of extra expense.' rials for carriages and horses in winter and wet
The ascent of hills, as observed by Marshal, is seasons: 2. A soft road, formed with the natural of course one of the most difficult parts of laying materials of the site, to be used in dry weather, out roads. According to theory, he says, an in- to save the unnecessary wear of the hard road, clined plane of easy ascent is proper; but as and to favor the feet of travelling animals; as the moving power on this plane is neither well as for the safety, ease, and pleasantness of purely mechanical, nor in a sufficient degree ra- travelling in the summer season : and 3. A comtional, but an irregular compound of these two modious path, for the use of foot passengers, at qualities, the nature and habits of this power' all seasons. But in these cases, he thinks, modern require a varied inclined plane, or one not a practice has simplified too much. Instead of uniform descent, but with levels or other proper these three requisites of a public road, we geneplaces for rests. According to the road act the rally find a parliamentary or turnpike road (away ascent or descent should not exceed the rate from the environs of great towns) consisting or proportion of one foot in height to thirty-five simply of one uniform broadway of hard matefeet of the length thereof, if the same be prac- rials; upon which horses stumble, and carriages ticable, without causing a great increase of disc jolt, the year round : while travellers on foot are tance. Mr. Telford, Minutes before the Com- seen wading to their ankles in mud, or in dust, mittee of the House of Commons, &c., 1819, according to the state of the wind and weather. referring to those which he has lately made his notions of what the nature of a public road through the most difficult and precipitous dis- ought to be is, that within the fences of a lane tricts of North Wales, says, the longitudinal or road there should be a raised foot-path, a inclinations are in general' less than one in convex hard road, a soft summer road, and chanthirty; in one instance for a considerable dis- nels to carry off the water collected by the cartance there was no avoiding one in twenty-two, riage roads; the foot-path being cut across in and in another, for about 200 yards, one in proper places, to permit the water, which falls seventeen; but, in these two cases, the surface of on that side of the middle road, to pass off freely the road-way being made peculiarly smooth and into the ditch at that side, as well as to prevent bard, no inconvenience is experienced by horsemen from riding along the path ; the oppowheeled carriages. On flat ground the breadth site hedge-bank being perforated, to let off, into of the road-way is thirty-two feet; where there the other drain on the contrary side, the waters is side cutting not exceeding three feet, the which may collect on that side of the lane or breadth is twenty-eight; and, along any steep road. Mr. Telford, Mr. Walker, and most ground and precipices, it is twenty-two, all other engineers, consider seventy feet a sufficient
width for roads near the largest towns and cities, extent of the run of commerce, or traffic, upon and that ten or twenty feet of this may in some the road. As a general rule however, for public cases be paved. The London Commercial roads over the different counties of Great BriRoad, constructed by the last-named engineer, is tain, I should suppose, he says, the following ‘of this width and character, and there are fifteen might in most cases be adopted. Take for infeet of gravel road at each side for light carriages stance the road betwixt Edinburgh and Glasgow, or horses. It has been executed for sixteen or betwixt Edinburgh and Aberdeen, by the way years, and has given the greatest satisfaction; of Dundee. These roads are formed in general but Mr. Walker thinks that considerable im- from thirty-five to forty feet wide; and the provement would be found from paving the breadth of the metals is from fourteen to sixteen sides of a road, upon which the heavy traffic is feet for the most part. Such roads as these great, in both directions, and leaving the middle would be found to answer very well, in general, for light carriages; the carmen or drivers, walk- over the kingdoin. A breadth sufficient for the ing upon the foot-paths or sides of the road, general purposes of country travelling, according would then be close to their horses, without in- to M'Adam, is sixteen feet of solid materials, terrupting or being in danger of accidents from with six feet on each side formed of slighter light carriages, which is the case when they are materials. The Bristol roads, he says, are made driving upon the middle of the road; and the with stone about the width of sixteen feet. unpaved part, being in the middle or highest part Narrow roads, it is well observed by Fry, are of the road, would be more easily kept in good almost always in bad condition, which is to be repair. But unless the heavy traffic in both di- accounted for from the circumstance of every rections is great, one width, say ten or twelve carriage being obliged to go in the same ruts; feet, in the middle of the road, well paved, will and, as each rut is generally only six inches wide, be found sufficient for all ordinary wear. The one foot of the road only is worn by the wheels width of many of the present roads is, besides, instead of the whole breadth of it; which would such, that ten or twelve feet can be spared for be the case if the road were of a proper width, paving, while twice that width would leave too and if it were well constructed. "If a road be little for the gravelled part. Although the first laid out from twenty to thirty feet wide, so flat cost of paving is great he does not think that as that a carriage may stand nearly upright on any other plan can be adopted so good and so every part of it, and if moderate care be taken cheap in those places where the materials got in by the surveyor to prevent the first formation of the neighbourhood are not sufficient for support- ruts, such a road will be worn by the wheels ing the roads. A coating of whinstone is, for nearly alike on every part of it: provided also instance, more durable than the gravel with that the ground on each side, for at least four or which the roads round London are made and five feet, be moderately fat, so as not to excite repaired; but much less so than paving; although fear in the drivers of carriages; but if there be the freight and carriage of the whinstone, and of deep ditches close to the sides of the road, or if the paving-stones, which form the principal items the circumjacent land fall off very abruptly to of the expense, are nearly the same.
the depth of two or three feet, whereby fear of Proportioning the breadth of roads to the traf- approaching the edges would operate on the fic for which they may be employed, has, per- minds of the drivers, every driver will instinchaps, not been sufficiently attended to. In tively avoid the danger on either hand ; and a remote places, where there is but little traffic, the road so circumstanced will, in spite of any waste of ground occasioned by superfluous care of the surveyor, inevitably be worn into width of roads, is an error : there being many ruts in the middle. There is a remarkable inplaces where roads of twenty feet breadth would stance of this kind in a piece of road on Durdsuit the public convenience, as well as if they ham Down, near Bristol. This road is a cause were twice as broad; and it is clear that, if a way over a piece of soft ground; and, although road is one pole or perch wider than is neces- it is from twenty to twenty-five feet wide, yet, as sary, there is a waste of 320 perches in a mile, the ground falls away abruptly on both sides of equal to two acres of ground, which, at the rate it, it has been found impossible, for more than of £3 per acre, would, if the road had been once twenty years past, to his knowledge, to prevent well made, keep half a mile of such road as is deep ruts being formed along the middle of it; here alluded to in good repair. According to notwithstanding the Down itself consists of hard Paterson, the breadth of the road and the width limestone; and the other roads upon the Down of the metals, or paved part, should depend on are as fine and even as any roads in England. circumstances different from the former. For a Were this piece of road widened out on each few miles in the vicinity of such cities as London side, in an easy slope about five feet, by rubbish or Edinburgh, the most proper breadth at which of any kind, and by the scrapings of the ioaà ita road should be formed, he thinks, is from sixty self, whereby the instinctive operation of fear of to seventy feet, and the metals from twenty-five approarhing the sides of the present road would to thirty-five feet; while, in the neighbourhood be obviated, that piece of road would be found to of such towns as Newcastle and Perth, it will be wear as fairly as the other roads on the same Down. sufficient that it be formed forty feet broad, and When roads run through marshy ground, obthat the width of the metals be about eighteen or serves Mr. Edgeworth, the substratum must be twenty feet. These are the breadths presumed laid dry by proper drainage; and where the to be the most eligible in such situations. But road is liable, from the flatness of the country, rules cannot be given to suit every situation : the to be at times under water, the expense of raisbreadth ought to be regulated according to the ing it above the water must be submitted to in the
first instance. All drains for carrying off water much more risk than the erection of other bridges. should be under the road, or at the field side of One low arch is thought by Mr. Loudon to be the fences, and these drains should be kept open in general the most desirable description of by constant attention, and should be made wide common road-bridges. But most of the country at the outlet.' Telford and Walker recommend bridges, as Clarke observes, consist of several the side drains to be in every instance on the small, high, semicircular arches : where there is field side of the fence. In cases, Telford observes, a single arch, the stream passes without interrupwhere a road is made upon ground where there tion; if there are two or three in the same situare many springs, it is absolutely necessary to ation, the space through which the water is to make a number of under and cross drains to pass is necessarily contracted by the width of collect the water and conduct it into the side piers. Ice, and large bodies carried down by the drains, which should always be made on the field foods, frequently stop up the small arches, and side of the fences. The orifices of these cross the accumulated water carries away the bridge; drains should be neatly and substantially finished but, if such accidents should not happen, the in masonry
Before the materials are put on, constant currents rushing against those piers run a drain along the middle of the road, all the wash out the mortar, loosen the stones, and very way, from two to three feet deep; then fill it soon undermine the work if it is not extremely with stones up to the surface, making those at well put together, which is seldom the case. bottom of a pretty good' size, and those at the Unless the river or stream is narrow, or the top full as small as the road materials. And, banks very high, a semicircle is an inconvenient in order that the quantity of stones used for the shape for an arch; it has been adopted on acsaid drain may be as little as possible, and every count of the insufficiency of the abutments, and way to save expense, it may be made as narrow because the pressure is more perpendicular; as it can possibly be dug. From this leading but scientific engineers, in all countries, now drain make a branch here and there to convey construct their bridges with wide openings, off the water to the canals on the sides of the and make the arches either semi-ellipses, or segroad.'-Paterson. This mode of draining he has ments of large circles ; so that the space above found from experience to be so beneficial that a the highest floods is comparatively little, and the road so drained would be better and more dura- ascent over the bridge inconsiderable. In country ble with eight inches, than it would otherwise be bridges in Ireland, Clarke continues, the foundawith twelve inches of materials. And not only tions are invariably, and often intentionally, deso, but that on such a road there would be a fective: the mason considers himself an honest saving on the incidental repairs, ever afterwards, man if his bridge lasts seven years; whereas, of about one-half of the labor, and at least one- from the durability of materials in that country, third of the material. • All moisture from under it ought to endure for ages. Whatever is under the road materials should be carried off by such water is out of sight, and is generally composed drains. Where such drains are wanting, the of loose stones, thrown promiscuously together, road, on the return of a thaw, throws up to the on which the masonry is erected, and all the surface all the water it had imbibed ; and in pains and expense are bestowed on the cutmany places the materials, swelling up, become waters and wings, when the heaviest stones, and quite loose and open. This is a natural conse- those accurately jointed, ought to be laid in the quence, where the material is not thick, and foundations. The greatest attention should be where the soil under the road is not perfectly paid to the quality of the materials : the stones dry. But, where a road is dried in the way de- should be large, and laid in level courses, in the scribed, it will be uniformly seen that the water, best mortar, composed of sharp sand, free from instead of spewing out on the return of a thaw, loam, and quicklime, accurately mixed together; is sucked in by the drains, so leaving the surface the coping of the parapet is generally so slight of the road quite dry. It may be observed, at that it is broken down as soon as built, and the such times, that the places of the road where a entire parapet quickly follows; it ought to be of few roods of such drain had been introduced, large heavy stones, roughly hammered, and there presented to the eye, at a quarter of a mile dis- should be substantial quoins at the ends of the tance, quite a contrast to the other parts of the parapets with an immovable stone over them. road; the one opaque and dry, from the moisture Arches not exceeding eight feet span may be being sucked in, the other all wet and glistering, semicircular; tunnels not exceeding eighteen from its being thrown out to the surface.'--Pa inches wide may be covered with strong flags, terson's Letters, &c., 44, 48, 84.
and either flagged or paved under, and there Embankments and bridges of different degrees ought to be across either end a deep long stone, of magnitude, are required in most lines of road. sunk below the surface of the current, and under Large bridges we must leave to engineers; no the walls, to prevent the water from undermindepartment of their art having attained higher ing the work. perfection. We here confine ourselves entirely Fences along the sides of roads are essential in to such stone arches as may be designed by all enclosed conntries; and all engineers and road-surveyors, and built by country masons. road-makers agree that they should never be alIn many cases cast-iron might be substituted for lowed to rise to a greater height than what is stone with economy and advantage as to water- necessary for a fence. To give free admission to way; but, though the principle of constructing the sun and air, by keeping the fences low, Marboth cast and wrought iron bridges is perfectly shall considers as providing an expensive, yet simple, the execution, and especially the putting most accurate method of cleaning roads, incomup, requires more skill, and is attended with parably more so than washing or scraping. Tlie