In your experience, have you observed that on gravel roads the materials are generally very unskilfully and improperly applied?—Generally so. I think always I may say, for I think I never saw them skilfully or properly managed.
Have you adopted the mode of washing the gravel?—No; I think that is a more expensive process than is necessary.
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 32l. 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.