450 Farm Mechanics. 



across the road at intervals to turn the water to the side 

 This is a bad practice and should be avoided wherever 

 possible, and in all but the steepest grades this may be done 

 by making the slope of the road higher than the grade. 



If the water cannot be turned off in this way it is bet- 

 ter to make two paved gutters meeting V-shaped in the cen- 

 ter of the road with the point up the grade. The paving will 

 prevent washing and making the gutters meet in the cen- 

 ter does not tip the wagon in passing across them. 



Whenever it becomes necessary to carry water across 

 a road on a hill from one gutter to the other it is much 

 better to carry it under the road than above it, as is so 

 often done with the aid of water-breaks. A culvert is of 

 course necessary but it should be used. 



TEXTURE OF EOAD MATERIALS. 



Closeness of texture is necessary to the building of a 

 solid road. The more completely all pores can be obliter- 

 ated and the road given the close texture of iron the better 

 and more durable will it be. 



Field soil in its natural condition may have from 30 

 to 50 per cent, of space unoccupied by anything but water 

 and air, and in this condition it cannot form a good road. 

 It is too yielding to pressure and water percolates through 

 it too rapidly. When it is properly rolled and tamped 

 the pore space is very greatly reduced, giving it so close 

 a texture that water does not enter it readily, and so large 

 a portion of the grains are in actual contact that it ap- 

 proaches the character of a rock. Of whatever material a 

 road is built it should permit the parts to pack so closely as 

 to resemble a solid rock. 



557. Roads Should Be Built in layers. Whether a road 

 is to be built of crushed rock or earth it is indispensable- 

 that the materials used shall be put on in layers. The 

 thickness of the layers will depend primarily upon the 



