and the depth at breaking is, 



d b => 0»09 x 10 2 - 9 ft. 

 From Figure 1, 



H b = 1,47 

 H 



and the height of the breaker is, 



H b = 1„47 x 5 = 74 ft. 



From Plate II of "Breakers and Surf", H. 0. No. 234, (Figure 2) a copy of 

 which is attached for convenience, the breaker angle is computed as follows: 



d b = 9 = 0„0176 ' 



ES~ (5.12) (10) 2 



Then from Plate II, for this value of d b /L and cc = 40°, the breaker 

 angle is, 



oc b = 12° 



This method of computation is an alternate method to the generalized 

 diagrams for forecasting breakers and surf presented above. 



It involves a trial and error computation; whereas, the method utiliz- 

 ing generalized diagrams does not, all computations being made graphically. 



30 



