Part 7
Do you think it more expensive than screening?—A great deal more so, and I have another reason for objecting to that, with respect to the gravel near London; the loam adheres so strongly to it that no ordinary washing will clean it. The loam is detached from the gravel by the united effort of the water on the road, and the travelling, by which the roads near London become so excessively dirty; but it would be impossible to detach the loam from the gravel in the pits, by throwing water on it; I have tried the experiment and know the fact.
To what particular practice do you allude, when you inform the Committee that gravel is unskilfully applied to the roads in general?—I see that on gravel roads, the gravel is put on after being very imperfectly sifted, and the huge pieces not being broken, and the gravel is laid on the middle of the road and allowed to find its own may to the sides. Now the principle of road-making I think the most valuable, is to put broken stone upon a road, which shall unite by its own angles, so as to form a solid hard surface, and therefore it follows, that when that material is laid upon the road, it must remain in the situation in which it is placed without ever being moved again; and what I find fault with putting quantities of gravel on the road is, that before it becomes useful it must move its situation and be in constant motion.
In order to attain the advantage you allude to in the angular materials, I take it for granted, it is your plan to have the larger pieces of gravel well broken?—Certainly; but I mean further, that in digging the gravel near London, and places where there are vast quantities of loam, and that loam adhering to every particle of the gravel, however small, I should recommend to leave the very small or fine part of the gravel in the pits, and to make use of the larger part which can be broken, for the double purpose of having the gravel laid on the road in an angular shape, and that the operation of breaking it is the most effectual operation for beating off the loam that adheres to the pieces of gravel. There are other cases besides that of gravel, in which I should think it unprofitable to lift a road. The road between Cirencester and Bath is made of very soft stone, and is of so brittle a nature, that if it were lifted it would rise in sand, and there would be nothing to lay down again that would be useful. I should not recommend lifting of freestone roads for the same reason, because it would go so much to sand that there would be very little to lay down again. I will explain what I have done to that road between Cirencester and Bath; I was obliged to lift a little of the sides of the road in order to give it shape, but in the centre of the road, we, what our men call, “shaved it;” it was before in the state which the country people call “gridironed,” that is, it was in long ridges with long hollows between, and we cut down the high part to a level with the bottom of the furrows, and took the materials and sifted them at the side of the read and returned what was useful to the centre.
Can you state whether the plan adopted on this road has increased or diminished the expense?—I think the expenses, by the last account, were rather within the expenditure of the former year, even including the new surveyor’s wages. They had been in the practice of allowing about 32_l._ a week to the two surveyors as the ordinary expenditure; I directed the new surveyors not to exceed that sum upon any account whatever, including their own wages: but formerly they paid that sum, and paid the surveyor his wages at the end of the quarter or half-year in addition: therefore I consider the sum expended upon the road is rather within the former expenditure than otherwise, except with regard to two dangerous slips which took place at Swainswick-hill, which I consider as perfectly extra.
In the formation of roads under your management, to what shape do you give the preference; I allude to the convex shape or the flat?—I consider a road should be as flat as possible with regard to allowing the water to run off 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 centre than I have at the sides, when they are 18 feet wide; if the road be smooth and well made, the water will run off very easily in such a slope.
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?—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 the water continually stands there: and I think that more water actually stands upon a very convex road than on one which is reasonably flat.
What width would you in general recommend for laying materials on a turnpike road?—That must depend upon the situation. Near great towns roads of course ought to be wider than farther in the country. Roads near great towns ought not to be less than thirty or forty feet wide, but at a distance from great towns it would be a waste of land to make them so wide.
You mean a breadth of thirty feet actual road?—Yes. The access to Bristol for a distance of about three miles, if we had room between the hedges, I would make about thirty feet wide. Between Bath and Bristol I should wish to see the road wide all the way, because it is only the distance of twelve miles between two large cities.
In what way do you make the watercourses at the sides of the road; I ask that question, having observed the farmers, in exercising their power of cleaning out their ditches, dig them to such a depth as to render them dangerous to be passed at night?—I always wished the ditch to be so dug as that the materials of the road should be three or four inches above the level of the water in the ditch, and to that point we endeavour to bring the farmers, but they are very unwilling to clean the ditches at any time when called upon, and when they do it, if they find vegetable mould in any quantity at the bottom of the ditch, they will prosecute their inquiry much deeper than is useful, or proper for safety.
Do you consider you have power by law, at present, for preventing that?—Yes; because the law says, they are to clean them out according to the directions of the surveyors.
In your experience have you found any impediment to the improvement of the roads, from a want of power in the proprietors of different navigations to lower their tolls for conveying materials?—I have found in the river Lea navigation, that the trustees have no power to lower their tolls, which were imposed by act of parliament upon merchandize, and therefore, it operated in a great measure as a prohibition to carry materials upon that river.
Do you consider it would be to the interest of the proprietors to allow materials to be carried on their navigations at a lower rate than they are empowered to allow by law?—Yes, if they could.
Do you know any similar instance as applicable to canals?—I don’t know an instance with respect to canal trusts, but there is an instance with respect to the Bath river at Bristol. No mitigation of the present rate of duty on that river can take place if objected to by any one proprietor, and therefore we have found great difficulty in carrying materials on the Bath river. In one particular place we have been entirely precluded from carrying any.
Have you found any impediment to the improvement of roads arising from the conditions upon which materials are permitted to be conveyed from one parish to another?—Yes; I found that in several cases in the Bristol district. One very strong instance occurred near Keynsham; we had a quarry close to the edge of one parish, and we could not carry the stones from it to the distance of ten yards, without the process of going to the magistrates.
Did you in that case make application to the magistrates?—I did intend to make application, but before I made that application, I found in the very next field, belonging to the same farmer, and in the parish where we required them, the necessary materials, and I was under the necessity of opening both the fields, to the detriment of the farmer’s landlord I am persuaded.
Do you know an instance of such an application as that to which you have alluded, having been made to the magistrates, and having been refused?—No, I do not.
Do you think that a great inconvenience and loss of time would be saved if that necessity of application was dispensed with?—It certainly is a great inconvenience, and creates a great deal of heart-burning in the country, and much dispute. I think the commissioners would very seldom be disposed to carry materials from one parish to another, unless for the general public good.
What depth of solid materials would you think it right to put upon a road, in order to repair it properly?—I should think that ten inches of well consolidated materials is equal to carry anything.
That is, provided the substratum is sound?—No; I should not care whether the substratum was soft or hard; I should rather prefer a soft one to a hard one.
You don’t mean you would prefer a bog?—If it was not such a bog as would not allow a man to walk over, I should prefer it.
What advantage is derived from the substrata not being perfectly solid?—I think, when a road ts placed upon a hard substance, such as a rock, the road wears much sooner than when placed on a soft substance.
But must not the draught of a carriage be much greater on a road which has a very soft foundation, than over one which is of a rocky foundation?—I think the difference would be very little indeed, because the yield of a good road on a soft foundation, is not perceptible.
To use the expression to which you have alluded, as being used by the coachmen, would a carriage run so true upon a road, the foundation of which was soft, as upon one of which the foundation was hard?—If the road be very good, and very well made, it will be so solid, and so hard, as to make no difference. And I will give the Committee a strong instance of that, in the knowledge of many gentlemen here. The road in Somersetshire, between Bridgewater and Cross, is mostly over a morass, which is so extremely soft, that when you ride in a carriage along the road, you see the water tremble in the ditches on each side; and after there has been a slight frost, the vibration of the water from the carriage on the road, will be so great as to break the young ice. That road is partly in the Bristol district. I think there is about seven miles of it, and at the end of those seven miles, we come directly on the limestone rock. I think we have about five or six miles of this rocky road immediately succeeding the morass; and being curious to know what the wear was, I had a very exact account kept, not very lately, but I think the difference is as five to seven in the expenditure of the materials on the soft and hard.
Do you mean seven on the hard and five on the soft?—Yes.
And yet the hard road is more open to the effect of the sun and air than the soft road?—It certainly lies higher.
Have you ever inquired of the coachmen, on which of those two descriptions of roads the carriages run the lightest?—Yes, I have; and I have found that there is no difference, if the road be equally smooth on the surface, whether it be placed on the soft ground or hard.
But in forming a road over a morass, would you bottom the road with small or large stones?—I never use large stones on the bottom of a road; I would not put a large stone in any part of it.
In forming a road across morass, would you not put some sort of intermediate material between the bog and the stone?—No, never.
Would you not put faggots?—No, no faggots.
How small would you use the stones?—Not to exceed six ounces in weight.
Have you not found that a foundation of bog sinks?—No, not a bit of the road sinks; and we have the same thickness of materials on the one as on the other.
If a road be made smooth and solid, it will be one mass, and the effect of the substrata, whether clay or sand, can never be felt in effect by carriages going over the road; because a road well made, unites itself into a body like a piece of timber or a board.
In making a road under these circumstances, do you make the whole of the depth of materials at once?—No, I prefer making a road in three times.
Three different times?—Yes.
To what size would you break the hard materials?—To the size of six ounces weight.
Do you not think that is an indefinite criterion; had you not better mention the size?—No; I did imagine myself, that the difference existed to which you allude, and I have weighed six ounces of different substances, and am confident there is little difference in appearance and none in effect; I think that none ought to exceed six ounces; I hold six ounces to be the maximum size. If you made the road, of all six ounce stones it would be a rough road; but it is impossible but that the greater part of the stones must be under that size.
Do you find a measure or ring through which the stones will pass, a good method of regulating their size?—That is a very good way, but I always make my surveyors carry a pair of scales and a six ounce weight in their pocket, and when they come to a heap of stones, they weigh one or two of the largest, and if they are reasonably about that weight they will do; it is impossible to make them come exactly to it. I would beg leave to say, in all cases of laying new materials upon an old road, I recommend loosening the surface with a pickaxe a very little, so as to allow the new materials to unite with the old, otherwise the new materials being laid on the hard surface never unite, but get kicked about, and are lost to the roads; wherever new materials are to be put down upon an old road, I recommend a little loosening; but that I don’t call lifting.
Have you stated what thickness of new materials you would lay down on an old road?—I should consider an old road would not want new materials if it had ten inches of materials before, but I should only pick up the materials, and break the large stones; and if there were any want of materials, I would lay on as much as would bring it up to somewhere about the ten inches.
Would you prefer doing that in dry weather or in wet weather?—In wet weather, always; I always prefer mending a road in weather not very dry.
Are you of opinion that any alteration of the present law, either in regard to the repeal of the present regulations or the enactment of new ones, could advantageously take place in regard to the shape of wheels, and the allowance of weight to be carried in waggons and carts?—I am of opinion that the descriptions of wheels given in all the acts of parliament in the last sessions are the most convenient and useful; and I have thought of the matter very much, without being able to suggest any alteration profitable to the public. With respect to weights, I consider there are very great difficulties in that business. We have weighing machines in the neighbourhood I now am in, and I am persuaded in many instances that they are made instruments of oppression, and in a great many cases the means of committing very great fraud on the commissioners and others; and if some method could be fallen upon by which weighing machines might be dispensed with altogether, and the road reasonably protected, I should think it a very great public advantage. In the new Bristol Act, I have proposed to the commissioners that they should submit to parliament to lay a toll-duty upon the number of horses in a progressive ratio, so as to compel those people who offend to bring in their hands the penalty in the shape of toll; I think it would prevent a great deal of that system of entering into combinations between the toll collectors and the waggoners, which is carried on to a great extent.
Do you think, that if horses in narrow-wheeled waggons were obliged to draw otherwise than at length, it would afford any protection to the road?—Yes.
Has not the practice of making horses draw at length very much a tendency to make the horses follow one track, be the road ever so good?—Yes; and I must mention to the Committee, that the feet of horses on ill-made roads do full as much mischief as the wheels. It is driving horses in a string that makes a road what the country people call “gridironed;” it is an odd expression, but it is a very significant one.
Do you not believe, that if horses were attached to narrow wheeled waggons in pairs, it would be found very considerably easier to drive and guide them when abreast, than when placed at length?—I should think it would.
And would it not tend to prevent accidents?—Horses driven in pairs would provide in a great measure against the accidents that arise from the carelessness of those persons who drive them, which is extremely great.
Do you think that if horses were put in pairs to waggons, the power of holding back those waggons when going down a hill, would be so much increased as to prevent the necessity of so frequently locking the wheels?—Certainly it would; because on certain slopes it would not be necessary to lock the wheels; but there are very steep hills where you cannot do without locking.
Is not locking wheels an operation extremely injurious to the roads?—I am not prepared to say it is, if the drag-iron, as it is called, be of a proper description. I followed a waggon lately, with seven tons of timber on it, down Park-street, at Bristol, being a very steep road, with both its hind wheels locked; and this waggon, with this weight of timber on in and with both the hind wheels locked, did not make the least impression from the top of the street to the bottom. You could discern where the drag-irons had gone, but they had not displaced the materials nor done any mischief.
Don’t you find locking generally injurious?—Extremely injurious; on rough roads it is dreadful.
Would not fewer ruts be made if it were more the custom for horses to draw in pairs?—I believe gentlemen are not generally aware of what a rut consists. There are two kinds of ruts, generally speaking: one is a rut produced by displacing ill-prepared materials, and that is the common rut. When a road is made of ill-prepared materials, the wheel piles them up one upon another, and that forms a very narrow rut, which just holds the wheel; but a rut made by wear upon a smooth surface, is rather a concave hollow than a rut, and will present no difficulty to a carriage in travelling, and that is the difference between a rut produced by wear in a very well-made road, and that produced by displacing the materials.
Is there not much injury done to the roads by the heavy weights both of coaches and waggons?—I am not disposed to think that upon a well-made road the weight of coaches is material, or that it would be judicious to make any legal provisions affecting that subject. In regard to waggons, I conceive that the loads carried upon wheels of the description encouraged by recent acts of parliament, whatever their weight, would be very little injurious to well-made roads. I think a waggon wheel of six inches in breadth, if standing fairly on the road with any weight whatever, would do very little material injury to a road well made, and perfectly smooth. The injury done to roads is by these immense weights striking against materials, and in the present mode of shaping the wheels they drive the materials before them, instead of passing over them, because I think if a carriage passes fairly over a smooth surface, that cannot hurt the road, but must rather be an advantage to it, upon the principle of the roller.
Are you not of opinion that the immense weights carried by the broad-wheeled waggons, even by their perpendicular pressure, do injury by crushing the materials?—On a new-made road the crush would do mischief, but on a consolidated old road the mere perpendicular pressure does not do any. But there is a great deal of injury done by the conical form of the broad wheels, which operate like sledging instead of turning fairly. There is a sixteen-inch wheel waggon which comes out of Bristol, that does more injury to our roads than all the travelling of the day besides.
Are you of opinion that any benefit arises from those broad-wheeled waggons, which would justify their total exemption from tolls?—None at all.
Does the answer you have given to the Committee relative to the effect of great weights, apply equally to roads made with gravel, as well as broken stone?—I mean it to apply to all well-made roads, whether of gravel or of other materials.
You mean after the road is smooth and solid?—Yes.
But with regard to a new road, are you not of opinion that the materials are crushed and worn out by a great weight?—Yes; no doubt that is so on a new-made road, and one of those waggons with the wheels made conical, would crush a greater proportion of stone than it ought to do.
Do you not conceive that the state of the turnpike roads would be improved by not allowing any waggons to carry more weight than four ton?—I don’t know that that would make any great difference, under good management. I think the defect lies in a want of science in road-making.
_Martis, 9° die Martii, 1819._
_John Loudon MᶜAdam_, Esquire, called in; and Examined.
In your evidence last week, you stated that less improvement had taken place in the roads in the neighbourhood of London than in any other district, to what causes do you attribute this circumstance?—I consider the principal cause to be the small extent of the trusts, and the peculiar situation of London, which increases the bad effects of the division into very small trusts.
What are the particulars of the situation to which you allude?—The situation of most of the roads near London is very low, difficult to be kept free from water, the traffic is very great both in weight and number, and therefore requiring more skill, as well as more care and attention, than the other roads of the kingdom; the material found near London for making the roads is gravel of a very bad quality, it is mixed with an adhesive loam that cannot be separated from the gravel, except by the united power of water and friction; this operation cannot be effectually performed before laying it on the roads, but is done by the rain and the traffic, producing a stiff mud, which is not only in itself an impediment to travelling, but has the effect of keeping the roads loose; the form of the gravel is also unfavorable, being smooth round masses of flint, without any angles by which the parts might unite. On the other hand, London is placed in a situation peculiarly convenient for being supplied with materials from a distance, by water carriage. The materials that may be so procured are of the very best description, and, under the sanction of parliament, may be procured on very moderate terms. The Thames furnishes gravel of a very good quality and quite clean; by using this gravel, the navigation of the river will be improved; the several canals, the Surrey, the Grand Junction, Paddington, and river Lea navigation, present facilities for procuring clean flint of the best kind; the coast of Essex, Kent, and Sussex, can furnish a supply to any extent of beach pebbles, one of the best road materials in the kingdom. Granite chippings might be obtained occasionally from Cornwall, Guernsey and Scotland, as ballast; two pieces of road were made with these materials near London, without any mixture of land gravel, at Blackfriars Bridge and Westminster Bridge.