Will you state your opinion of the statute labour, as it particularly applies to turnpike roads?—In all the local road acts which I have examined, one half of the statute duty of each township is apportioned to each toll road which passes through any part or corner of that township, which in innumerable instances, is very highly prejudicial; a due proportion of the fair road rate, as already mentioned, should be payable to each toll road, where there are more than one in the township, in proportion (or nearly so, as the quarter sessions might order) to all the lengths of all the roads within the township which it contributes to repair.
From your observation of the different roads throughout the kingdom, do you think that important advantages would be derived from their being placed under skilful surveyors, acting for large districts?—At present, the separate trusts are so exceedingly different in extent, many of them extending only three, four and five miles, while others have fifty or a hundred miles of road under their trusts, that it seems impracticable, in many trusts, to employ a very skilful and competent surveyor, on account of the great and unnecessary expense that would be incurred on the short lengths of road; but if the legislature should see it right to enact the appointment of thoroughly competent district surveyors, who might have the superintendence and control, to a defined extent, over the officers of the local trustees of turnpike roads, as well as over the surveyors of the parish roads within their districts, the most important advantages would result.
Do you not think great inconvenience arises from the great numbers generally found forming commissioners of turnpike trusts?—From my own experience, I cannot say that I have seen any evil from the great number of trustees, on the contrary, the greatest mismanagement that I have seen in any roads, has arisen from the clergymen of the districts being almost the only acting trustees; the greatest and most active land owners frequently having no share in such trusts: the late duke of Bedford, for instance, not being a trustee in the vicinity of Woburn for many years after he took an active part in improving the district.
James Walker, Esq. called in; and Examined.
You are a civil engineer?—I am.
In the course of your experience have you turned your attention to the making and repairing of roads?—I have been employed in the making and repairing of several roads, and the regulation of others.
In what part of the kingdom have you been employed, and what observations have occurred to you upon this subject?—The whole of the works executed under the Commercial Road, the East India Road, the Barking Road, and the Tilbury Road Acts, have been under my direction, as well as the roads made under the Bridge and Dock Companies, for which I have been engineer. The Commercial Road, which is between the West India Docks and London is referred to in the report of a former Committee on highways, as particularly well fitted for heavy traffic; that road is seventy feet wide, and is divided into two footways, each ten feet, and a carriage road fifty feet wide, of which twenty feet in the middle is paved with granite. I have a section of the form of this road (No. 1, in the annexed plan.) The East India Dock branch of the Commercial Road is also seventy feet wide, ten feet of which is paved with granite. I have prepared also a section of that road (No. 2, in the plan.) The traffic upon the Commercial Road, both up and down, is very great, and necessarily required a width of paving sufficient for two carriages to pass upon it. I am quite sure that the expense of this road would have been very much greater, probably much more than doubled if it had not been paved, and that the carriage of goods would also here been much more expensive; indeed it would have been next to impossible to have carried the present loads upon a gravelled road. The road has been paved for about sixteen years, and the expense of supporting it has been small, although the stage-coaches generally, as well as almost all the carts and waggons, go upon it; while the expense of the gravelled part has been comparatively great. During the thirteen years that the East India Dock branch has been paved, the paving has not cost 20l. in repairs, although the waggons, each weighing about five tons, with the whole of the East India produce, which is brought from the docks by land, have passed all that time in one track upon it, and a great deal of heavy country traffic for the last eight years, when a communication was formed with the county of Essex. The advantage of paving part of a road where the traffic is great, and the materials of making roads bad or expensive, is not confined to improving the conveyance for heavy goods and reducing the horses’ labour; but as the paving is always preferred for heavy carriages, the sides of a road are left for light carriages, and are kept in much better repair than otherwise they could possibly be. It is not, I am sure, overstating the advantage of the paving, but rather otherwise, to say, that taking the year through, two horses will do more work, with the same labour to themselves, upon a paved road than three upon a good gravelled road, if the traffic upon the gravelled road is at all considerable, and if the effect of this, in point of expense, is brought into figures, the saving of the expense of carriage will be found to be very great when compared with the cost of the paving. If the annual tonnage upon the Commercial Road is taken at 250,000 tons, and at the rate of only 3s. per ton from the Docks, it could not upon a gravelled road be done under 4s. 6d. say however 4s. or 1s. per ton difference, making a saving of 12,500l., or nearly the whole expense of the paving in one year. I think I am under the mark in all these figures, and I am convinced therefore that the introduction of paving would, in many cases, be productive of great advantage, by improving the gravel road, reducing the expense of repairs, and causing a saving of horses’ labour much beyond what there is, I believe, any idea of. The expense of a ton of Aberdeen granite paving-stones laid in London, or in any similar situation, including laying, and every expense, is about 25s.; the cost of the same weight of gravel is from 3s. 6d. to 5s. The cost of granite paving, 9 inches deep, is from 8s. 6d. to 10s. 6d. per superficial yard, or from 750l. to 920l. per mile for every yard in width. Guernsey granite is harder and more durable than Aberdeen granite, but is more expensive by about 10 per cent. and I think is this much better. Some stone of very good quality from near Greenock, has been used lately upon the Commercial Road, it is cheaper than Aberdeen, and appears to be very durable. The requisites for forming a good paving are to have the stones properly squared and shaped, not as wedges, but nearly as rectangular prisms; to sort them into classes according to their sizes, so as to prevent unequal sinking, which is always the effect of stones, or rows of stones, of unequal sizes being mixed together; to have a foundation properly consolidated before the road is begun to be paved, and to have the stones laid with a close joint, the courses being kept at right angles from the direction of the sides, and in perfectly straight lines, the joints carefully broken, that is, so that the joint between two stones in any one course shall not be in a line with, or opposite to a joint in any of the two courses adjoining. After the stones are laid they are to be well rammed, and such of the stones as appear to ram loose, should be taken out and replaced by others; after this the joints are to be filled with fine gravel, and if it can be done conveniently, the stability of the work will be increased by well watering at night the part that has been done during the day, and ramming it over again next morning. The surface of the pavement is then to be covered with an inch or so of fine gravel, that the joints may be always kept full, and that the wheels may not come in contact with the stones while they are at all loose in their places. Attention to these points will very much increase both the smoothness and durability of the paving. I have found great advantage from filling up, or, as it is called, grouting the joints with lime-water, which finds its way into the gravel between and under the stones, and forms the whole into a solid concreted mass. The purpose served by the lime might also be effectually answered by mixing a little of the borings or chippings of iron, or small scraps of iron hoop, with the gravel used in filling up the joints of the paving. The water would very soon create, an oxide of iron, and form the gravel into a species of rock. I have seen a piece of rusty hoop taken from under water, to which the gravel had so connected itself, for four or five inches round the hoop, as not to be separated without a smart blow of a hammer. And the cast-iron pipes which are laid in moist gravel soon exhibit the same tendency.
It has occurred to me, as I stated to the chairman of this honourable Committee some weeks since, 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 walking upon the footpaths 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. I have prepared a section of a road formed in this way (No. 3 in the plan), but unless the heavy traffic in both directions is great, one width (say ten or twelve feet, if very well paved,) will be found sufficient; and in this case, I think the paving ought to be in the middle of the road. 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 so great, I do not think that any other plan can be adopted to 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. Scotch whinstone, or the granite rubble (that is, rough chippings of granite,) could not, I should think, be delivered into barges in the river, at less than from 14s. to 15s. per ton, the freight alone being from 11s. to 12s., while the price of Aberdeen granite, in the same situation, is only from 19s. to 21s. and 22s. Maidstone ragstone in the rubble state, costs about 7s. per ton: it is a limestone, and much less durable than the whin. The carriage from the river to the road, of all these, is of course the same. Flint, again, is so much less durable than whin, that it will not bear the expense of carriage (which may be taken at from 1s. 6d. to 2s. per ton per mile) from any distance, to make it preferable to the gravel, or paving, in point of cost, for the roads near London. A double iron rail-road, to suit the London waggons, which some have recommended, would cost about 4,500l. per mile, and would be fitted for waggons only of one precise width, and for waggons or heavy carts only; while, from the difficulty of crossing it, it would form rather an obstacle to light carriages. Blocks of Aberdeen granite, twelve inches wide and fifteen inches deep, laid in the way of the wheels (as recommended by others,) would be nearly as expensive; and the eight joints, which would be formed between the stone and the gravel, by four rows of stone, would be found extremely troublesome and inconvenient. Both these substitutes for paving, therefore, though equally expensive as paving, have peculiar disadvantages; and they have this besides, which is common to them both, that they make no provision for preventing the great wear upon gravelled roads, which is caused by the horses’ feet, particularly if (as is the case in a rail-road) they are confined in one track.
Attention in the forming and repairing of roads, will in all cases do much to compensate for the inferiority of the material used for that purpose, of which the improvements in the general state of the highways within the last twenty years affords the best proof. To form the road upon a good foundation, and to keep the surface clear of water after it is formed, are the two most essential points towards having the best roads possible, upon a given country, and with given materials. 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 avoiding low ground by raising the surface of the road 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. It is in the knowledge of the above points, and of the application of them in practice, that what may be called the science of road-making consists, as the observations apply in every case. When a road is to be formed, accurate sections of the rises and falls of the ground should always be taken, in the same way as is done for a canal, before the line is determined, or the levels of the road fixed upon, and when the course and levels of the road are laid down, the derail of the work ought to be particularly explained by a specification and plan, describing the manner in which each particular length is to be formed and completed.
The quantity of materials necessary to form the road depends so much upon the soil and the nature of the materials themselves, that it is impossible to lay down any general rules for them. The thickness ought to be such that the greatest weight will not affect more than the surface of the shell, and it is for this purpose chiefly, that thickness is required, in order to spread the weight which comes upon a small part only of the road over a large portion of the foundation. When the ground is very soft, trees, bavins or bushes, are applied to answer the same purpose, and to carry off the water previous to the materials of the road being so consolidated as to form a solid body, and to be impervious to water. Bushes are, however, not advisable to be used, unless they are so low as always to be completely moist. When they are dry and excluded from the air they decay in a very few years, and produce a sinking in place of preserving the road; a thickness of chalk is useful for the same purpose in cases where bushes are improper, the chalk mixing with the gravel or stones becomes concreted, and presents a larger surface to the pressure. If the material for making the roads is gravel, the common way is to lay it as it comes from the pit, excepting the upper foot, or 18 inches or so, which is screened; but if whin or other stone is to be used, the size of the pieces into which it is broken should decrease as we approach the surface, the superficial coating not exceeding a cube from 1 inch to 1½ inch. If the foundation is bad, breaking the bottom stone into small pieces is expensive and injurious, upon the principle I have above described, and also for the same reason that an arch formed of whole bricks or of deep stones is to be preferred to one of the same materials broken into smaller pieces, for in some counties the materials will admit of the foundation of the road being considered as of the nature of a flat arch, as well as of being supported by the strata directly under it: but the error in laying the stone in large pieces upon the surface is more common and more injurious. In all cases, whether the material is gravel or hard stone, the interstices between the pieces should be filled up solid with smaller pieces, and the finishing made by a thin covering of very small pieces, or road-sand or rubbish, for those interstices must be filled up before the road becomes solid, either in this way or by a portion of the materials of the road being ground down, which last mode occasions a waste of the material, and keeps the road unnecessarily heavy and loose. This observation applies to the repairing as well as the original making of roads, and the effect of this covering, or as it is called in the country, blinding the loose stones, is so evident, that I have often wondered to see so little attention paid to it. If the material is soft, as some limestone, this is less necessary, and the quantity ought never to be more than is just sufficient for the purpose I have described. In the original making or effectually repairing of a road, it is, I think, best that the whole of the proposed thickness be laid on at once, for the sake of the road as well as of the traveller; the materials of the road then form a more solid compact mass than when they are laid in thin strata, at different times, for the same reason that a deep arch of uniform materials is preferable to a number of separate rings. Though I state that an inclination in the longitudinal section of the road is always desirable for the purpose of clearing it of water, I am not of the opinion of those who recommend the road to be made and kept flat or level in its cross section. The variety of opinions and practice upon this point are very great; both extremes appear to me to be bad. A road much rounded is dangerous, particularly if the cross section approaches towards the segment of a circle, the slope in the case not being uniform, but increasing rapidly from the nature of the curve, as we depart from the middle or vertical line. The over rounding of roads is also injurious to them, by either confining the heavy carriages to one track in the crown of the road, or if they go upon the sides, by the great wear they produce, from their constant tendency to move down the inclined plane, owing to the angle which the surface of the road and the line of gravity of the load form with each other, and as this tendency is perpendicular to the line of draught, the labour of the horse and the wear of the carriage wheels, are both much increased by it.