SURF AROUND BAYS 



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25 : 1 to begin with, so that the waves 6 feet high in deep water and 

 250 feet long would produce breakers at least 6.5 to 7 feet high at A, 

 and 6 to 6.5 feet high at B and at C. But waves of that same 



at 40 



at ao c 



Figure 47. — Diagram of a short, rounded beach with waves advancing parallel 

 with its central sector (above), and at an angle of 40° with its central sector 

 but parallel with one of its flanks (below) 



height offshore, but 100 times as long as high (as swells often are), 

 might be expected to rise to heights of nearly 8 feet at B and at C, 

 as contrasted with a little more than 9 feet at A. 



These examples illustrate the general rule — well recognized by 

 persons who have to do with surf — that when the wave crests offshore 



