MACADAM, GRAVEL, AND EARTH ROADS 1 59 



well as during and following heavy rains at other seasons. In 

 short its perfection for all seasons is apparently impossible 

 and it depends upon constant, though inexpensive, attention 

 to minute repairs for its favorable condition during a limited 

 season. 



It thus appears that, if we aim at durability, nothing less 

 than a body of rock will keep us up out of the mud in the 

 spring; that this will render the surface too dry for comfort 

 iind durabilitv during the summer, and that the more expen- 

 sive and more perfect the surface constructed upon this 

 foundation, the more expensive and more difficult the matter 

 of repair. In the city sprinkling has given greater durability 

 and comfort to the macadam surface, and the heavy expense 

 for construction and maintenance can often be easily borne. 

 In the country these favorable conditions are usually absent. 

 Some have attempted to find in the gravel road the safe middle 

 course between the earth and the macadam. They do not, 

 however, appear to have wholly succeeded. 



Smoothness, elasticity, freedom from dust, low cost, and 

 cheapness of maintenance seem to be thus far more or less 

 incompatible with durability and constancy throughout the 

 year. 



It remains to be proved whether oiling the surface of a dirt 

 road which has been underlaid where necessary by some form 

 of rock to maintain the body of the road-bed or planting trees 

 thickly on both sides of such a highway to conserve by their 

 shade the natural moisture, will furnish to important country 

 roads of not the heaviest traffic the combined qualities of 

 smoothness, elasticity, freedom from dust, ease of repair, fair 

 durability, and not excessive first cost. The despised clay 

 may yet furnish the body of a material which will possess 

 many of these desirable qualities when drainage can be thor- 

 oughly attained. With a substratum of crushed stone or coarse 

 gravel or for a road surface close to ledge, no ordinary mate- 

 rial can surpass it, especially on a grade. At any rate the neces- 

 sary limitations of first cost should impel us to make a careful 

 study of combinations of natural materials with a view to their 

 most effective utilization. VVe can aftbrd to clay, gravel, or 

 sand a road when macadamizing would be out of the question. 



