ROADS 211 



result is a softly burned clay which makes a good road in 

 wet weather but has a tendency to become dusty in dry 

 weather. Only a few localities have the necessary fuel 

 available and the proper kind of clay for making such a 

 road. The burning must be superintended by an experi- 

 enced person who understands the arranging of the fuel and 

 clay to get the best results. 



Sand. In fine, sandy soil where clay and gravel are not 

 available fairly good results are secured by a mixture of 

 some vegetable matter with the sand, such as sawdust, 

 tanbark, straw, or worthless hay. The vegetable matter 

 should be placed on the road in thin layers, and as soon 

 as it has been worked in by the traffic another layer 

 placed. 



Shell. Shells make a satisfactory road covering in locali- 

 ties along the coast where they can be secured. 



Charcoal. Charcoal has been used for roads to a limited 

 extent by the burning of refuse wood on the road, similar 

 to the method of making burnt-clay roads. 



Progressive road building. In the greater number of 

 localities it is not practical from a financial standpoint to 

 secure the ideal road at once. Where this is true, attention 

 should be given to future needs, such that the work will not 

 be entirely wasted for later improvement. Good locations 

 should be selected and roadbeds graded and drained. 

 These will be advantages for any type of superstructure. 

 If it is not possible to prepare a road entirely, it should be 

 done in such a way as not to increase the cost of later devel- 

 opments. A sufficient width of roadway can be left, and 

 the greater part of the earth for grading taken from one 

 side, the other side to be completed at some time in the 

 future. Too often grades are thrown up or ditches made 

 that must be destroyed by later work, making the cost 

 greater than if they had never been made. While it is true 

 that the exigency of the case or the shortage of money may 

 compel the construction of road work that may have no 



