Page:Historic highways of America (Volume 10).djvu/68

68 raked smooth. The old material was used when it was of sufficient hardness, and no clay or sand was allowed to be mixed with the stone.

In replacing the covering of stone, it was found best to lay it on in layers of about three inches thick, admitting the travel for a short interval on each layer, and interposing such obstructions from time to time as would insure an equal travel over every portion of the road; care being taken to keep persons in constant attendance to rake the surface when it became uneven by the action of wheels of carriages. In those parts of the road, if any, where materials of good quality could not be obtained for the road in sufficient quantity to afford a course of six inches, new stone was procured to make up the deficiency to that thickness; but it was considered unnecessary, in any part, to put on a covering of more than nine inches. None but limestone, flint, or granite were used for the covering, if practicable; and no covering was placed upon the bed of the road till it had become well compacted and thoroughly dried. At proper intervals, on the slopes