Brig. Gen. C. Gratiot,
Chief Engineer.
EXTRACTS FROM “MACADAM ON ROADS,” MADE BY CAPTAIN DELAFIELD IN SUPPORT OF HIS VIEWS RELATING TO THE PAVEMENT FORMING THE BED OF THE “CUMBERLAND ROAD EAST OF THE OHIO.”
Page 39.—“It would be highly unprofitable to lift and relay a road, even if the materials should have been originally too large. The road between Cirencester and Bath is made of stone too large in size. In this case I recommend cutting down the high places,” &c.
Page 40.—“A part of the road in the Bath district is made of freestone, which it would be unprofitable to lift. Other cases of several kinds have occurred where a different method must be adopted, but which it is impossible to specify, and must be met by the practical skill of the officer, and who must constantly recur to general principles.”
Page 42.—“The price of lifting a road, &c., leaving the road in a finished state, has been found in practice to be from 1d. to 2d. per superficial yard, lifted four inches deep.”
Page 47.—“It is well known to every skillful and observant road-maker, that if strata of stone of various sizes be placed on a road, the largest stones will constantly work up.” (This is in no manner applicable to a pavement, and a road made even in the manner he alludes to was lifted only four inches deep.—R. D.)
Page 105.—“How deep do you go in lifting the roads? That depends upon circumstances, but I have generally gone four inches deep. I take up the materials four inches, and, having broken the large pieces, I put them back again.”
“Does the plan which you have mentioned, of breaking up the roads, apply to gravel roads, or only to those roads composed of hard stones? In gravel roads, and in some other roads, it would be impossible to break them up to advantage; and, in several places, I should think it unprofitable to lift a road at all. I did not order the road near Reading to be lifted, but I directed, whenever a large piece of flint was seen, it should be taken up, broken, and put down again. I am speaking of a gravel road now.”
Page 107.—“There are other cases besides that of gravel, in which I should think it unprofitable to lift a road. The road between —— and —— 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 the 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 center of the road we ‘shoved it.’ It was before in the state which the country people call gridirons: that is, it was in large 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 road, and returned what was useful to the center.”