DAVIS. — OUTLINE OF CAPE COD. 



325 



sity only approximate, but they are believed to give a fair iiulicatiou 

 of the order of magnitudes involved, both in space and time. We may 

 then infer that when the general outline of the back of the Cape had 

 assumed the position of the line AFiBH, the shore was well enough 

 graded to supply material for the building of a spit ; and that the 

 curvature of the shore at the point Fi, assigned for the beginning of 

 the spit, was such that the dbminaut 'long-shore currents, moving from 

 south to north in flood tide or under southeast storms could no longer 



Fig. 6. 



follow the shore, but departed from it outwardly by a small angle- 

 Thus the protecting bar, FiE, began to grow in front of the High 

 head cliff. 



At an earlier stage the 'long-shore currents must have been much 

 interrupted by the irregularities of the original shore line. No large 

 and well developed current could at that time follow these irregulari- 

 ties. But as the headlands were cut back and the bays bridged across, 

 and the shore assumed the outline ABH, then the resistance to the 

 development of the current became less and less ; thereby the 

 current became stronger and stronger, and desired a straighter 

 and straighter path for its movement. At the same time, a greater 

 and greater volume of waste was supplied from the growing cliffs. 

 As long as the back of the Cape pi-ojected farther into the sea than 



