CAPILLARY ATTRACTION. 



99 



and. the following diagram, taken from a description 

 of his system of draining, will explain the stratifica- 

 tion and springs more clearly. 



^\m,\\^w,ak.m::kk:^^^^^^^^kv>: ^^\m^M^i^ 



" In some districts, where clay forms the staple 

 of the soil, a bed of sand or gravel, completely sat- 

 urated with water, occurs at the depth of a few feet 

 from the surface, following all the undulations of 

 the country, and maintaining its position, in relation 

 to the surface, over considerable tracts — here and 

 there pouring forth its waters in a spring, or denot- 

 ing its proximity by the sub-aquatic nature of the 

 herbage. 



" Such a configuration is represented in the follow- 

 ing diagram, where (a) represents the surface-soil ; 



(b) the impervious subsoil of clay; (c) the bed of 

 sandy clay or gravel ; and [d) the lower bed of clay 

 resting upon the rocky strata beneath." 



3. The moisture rises to the soil hy capillar}/ attrac-^ 



