Lewis 



frequencies of encounter can vary either with ship speed or wave length, and 

 this leads to a great deal of confusion. The procedure outlined in the paper, if 

 properly used, gives the same numerical results as the conventional procedure 

 and therefore cannot be incorrect. Moreover, the graphs that can be prepared 

 in the course of the work are much more meaningful than the numbers alone, as 

 one finds with practice. Mathematics should be a tool, not a straitjacket. 



It is correct that the area under the log- slope wave spectrum is equal to 

 the mean squared wave slope rather than the mean slope. I agree entirely with 

 Mr. Vassilopoulos' closing paragraphs and have been working in the directions 

 he suggests for a long time. 



Dr. Yamanouchi has made a valuable contribution* which can stand on its 

 own as an important paper. Therefore, I shall simply thank him for presenting 

 it to the Symposium. 



I wish to thank all of the discussers for their interest in my paper and for 

 their very valuable comments. 



*See remarks by Yamanouchi on paper by Ogilvie. 



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