Page:Historic highways of America (Volume 15).djvu/136

 to the fundamental principles of drainage. As a result of such thoughtless and haphazard methods the road usually becomes rougher and more completely covered with holes than before.

In constructing a gravel road the roadbed should first be brought to the proper grade. Ordinarily an excavation is then made to the depth of eight to ten inches, varying in width with the requirements of traffic. For a farm or farming community the width need not be greater than ten or twelve feet. A roadway which is too wide is not only useless, but the extra width is a positive damage. Any width beyond that needed for the traffic is not only a waste of money in constructing the road, but is the cause of a never-ending expense in maintaining it. The surface of the roadbed should preferably have a fall from the center to the sides the same as that to be given the finished road, and should, if possible, be thoroughly rolled and consolidated until perfectly smooth and firm.

A layer, not thicker than four inches, of good gravel, such as that recommended above, should then be spread evenly over