THIRD ANNUAL YEAR BOOK — PART I. 35 



should be carefully maintained during the rolling by the addition of earth 

 as needed. 



SBB 



Fig. 16.— Properly crowned and well-drained earth road. Note slope from center to sides. 

 Road was worked with road machine and horse roller in March; photograph taken 

 June 1, about 48 hours after long, hard rain . 



TREATMENT OF CLAY ROADS. 



On clay roads a thin layer of sand, gravel or ashes will prevent the 

 sticking of clay to the roller or to the wheels of vehicles. Clay soils as 

 a rule absorb water quite freely and soften when saturated, but water 

 does not pass through them readily. When used alone clay is the least 

 desirable of all road materials, but roads composed of clay may be treat- 

 ed with sand or small gravel from which a comparatively hard and com- 

 pact mass is formed, which is nearly impervious to water. Material of 

 this character found in the natural state comimonly known as "hardpan" 

 makes, when properly applied, a very solid and durable road. In soil 

 composed of a mixture of sand, gravel and clay, all that is necessary to 

 make a good road is to crown the surface, keep the ruts and holes filled, 

 and the ditches open and free. 



TREATMENT OF SAND ROADS. 



While clay alone never makes a good road, except in dry weather, 

 sand alone never makes a good road except in wet. The more the drain- 

 age of a sand road is improved the more deplorable becomes its condi- 

 tion. Nothing will ruin one quicker than to dig a ditch on each side 

 and drain all the water away. The best way, therefore, to make such 



