166 



BREAKER DIRECTION AND HEIGHT 



scribed more than a century ago. And situations of the sort are not 

 uncommon. In situations, however, where the direction of the coast 

 alters abruptly, and when the waves are advancing at an angle of 

 more than, say, 90° with the sheltered side of a promontory, the re- 

 fraction of their inshore ends may expand their crests sidewise so 

 suddenly and so widely, (as illustrated in fig. 51), that the resultant 

 breakers decrease abruptly in height as they pass inward along the lee 

 shore. And the actual loss of energy from the inshore ends of the 



Figure 51. — Diagram to illustrate the refraction of waves around an abrupt cor- 

 ner of the coast, when the wave crests in deep water form angles of about 35° 

 with the more exposed shore and of about 155° with the more sheltered shore. 

 The depths of the bottom contours are given in terms of the offshore wave 

 length. The arrows indicate the lines of advance of the waves at successive 

 points along their crests. 



waves, as they break, tends to reduce their heights still further, as 

 they continue their advance, just as happens along the shores of a 

 long, funnel-shaped bay (p. 162). 



Short waves may, indeed, suffer so little refraction, as they pass an 

 abrupt alteration in the trend of a coast where the water is moderately 

 deep close in to the tide line, that they do not follow around to the 

 more sheltered shore at all, but continue right on past the corner, and 

 so out into deeper water again, leaving what may be termed a "shadow 

 zone" of quiet water, which may be of considerable extent, along the 



