238 



EARTH FEATURES AND THEIR MEANING 



material quarried upon headlands by the waves is diverted from 

 the offshore terrace. This diversion is the work of the shore cur- 

 rent produced by the wave. 



At but few places upon a shore will the storm waves beat per- 

 pendicularly, and then for but short periods only. The broken 

 wave, as it crawls ever more slowly up the beach, carries the sand 

 with it in a sweeping curve, and by the time gravity has put a stop 

 to its forward movement, it is directed for a brief instant parallel 

 to the shore. Soon, however, the pull of gravity upon it has started 

 the backward journey in a more direct course down the slope of 



FIG. 259. Map to show the nature of the shore current and the forms which are 



molded by it. 



the terrace; and here encountering the next succeeding breaker, 

 a portion of the water and the coarser sand particles with it are 

 again carried forward for a repetition of the zigzag journey. This 

 many times interrupted movement of the sand particles may be 

 observed during a high wind upon any sandy lee shore. The " S3t " 

 of the water along the shore as a result of its zigzag journeyings 

 is described as the shore current (Fig. 259), and the effect upon 

 sand distribution is the same as though a steady current moved 

 parallel to the shore in the direction of the average trend of the 

 moving particles. 



The sand beach. The first effect of the shore current is to 

 deposit some portion of the sand within the first slight recess upon 

 the shore in the lee of the cliff. The earlier deposits near the cliff 



