746 



C. R. VAN HISE 



descent. In proportion as the entering water is near the valley 

 the horizontal component becomes more important. The water 

 near the valley follows a comparatively shallow course; but this 

 water uses all the available space near the surface, and conse- 



Fig. 5. 



quently the water entering at the higher ground necessarily 

 follows a long, circuitous, and deep course. The chart (Fig. 5) 

 therefore represents the flowage with many points of entrance 

 and a single point of exit, where there is interference of the 

 circulating waters. 



Thus far it has been supposed that the ground is uniformly 

 porous, like an evenly grained sandstone without joint or fracture 



