288 FARM DEVELOPMENT 



ests of the traveling public and those interested in com- 

 bining the draining of the adjoining swampy fields with 

 the drainage of the roadway. The road line should be 

 located where the moving of materials needed to cover 

 the roadway in the swampy land will not be too expen- 

 sive. In the beginning only a few general roads should 

 be made at rather wide intervals across large swampy 

 areas, the cross roads being constructed later on. 



Survey for construction. Once the line of road is deter- 

 mined, and in a general way the depth of the cuts and fills 

 decided upon, there should be a survey for construc- 

 tion. Specifications should be made, even if only cheaply 

 surveyed in cases of light grades, for the depths to 

 excavate each cut and to fill each grade. Likewise, 

 specifications should be made for the kinds of material 

 to use in constructing the surface, the depths to place 

 each layer of surfacing material, and the manner of lay- 

 ing, mixing and packing these layers. Specifications 

 should be made for bridges and culverts. In determin- 

 ing upon the grade many things must be taken into 

 consideration. The rule followed by some railroad 

 engineers that a certain grade, say 20 feet to the mile 

 throughout the entire line, shall not be exceeded, is not 

 quite so important in highway engineering as in railroad 

 construction. Horses drawing a load, or men propelling 

 a bicycle, have stored up energy, which by an extra 

 effort may be utilized in larger amounts for a short time. 

 This enables the horse or bicyclist to mount unusually 

 steep grades if they are not too long. As automobiles 

 come into general use for carriage and freight purposes, 

 and rural electric railways are used, there is greater need 

 of avoiding steep grades in our wagon roads even for 

 short distances. A copy of the profile and of the notes 

 showing the depths at the cross-section stakes should 

 be furnished to the contractor or superintendent of con- 

 struction. 



