Drives anfc Walfes. 



77 



uniform size, as large as peas or hazel-nuts, up to an inch in 

 diameter, are often found in large quantities on the sea- 

 shore. These are excellent for the construction of all kinds 

 of walks and drives in a garden. If the walk is small and 

 the road-bed has been made perfectly solid by means of 

 ramming, a layer of these, about two inches deep, spread 

 over the ground and beaten down firmly, will make a dry 

 and durable path in 

 most places. On low 

 ground it is practical 

 to make road material 

 thickest in the middle, as shown in the diagram, Fig. 40. 



Fig. 41 shows a section of a drained walk on clayey soil. 

 As the clay prevents the water from sinking, the drain 

 is necessary to carry 

 away the water after 

 heavy rains. After 

 draining through the 



FIG. 40. SHELL WALK ON LOW GROUND. 



FIG. 41. DRAINED WALK OR DRIVE ON LOW GROUND. 



covering, or making 



its way from the edge 



of the walk along the 



scooped-out surface of 



the bed, it sinks without difficulty to the drain. Special 



drainage for drives and walks is needed only on flat and 



low land, or where the subsoil is stiff and impenetrable. In 



all places where the 



subsoil is gravelly or 



porous, drainage is 



FIG. 42. SIMPLE GRAVEL PATH. 



superfluous. If the 



incline of a drive is very steep, the edges are likely to be 



