plete programme would be a formidable undertaking were it not for the fact that the 

 development of theory points the way to a strict limitation of the range of useful 

 variation of the characteristics to such a degree that the requirements for experiment 

 can be reduced to a scope that do not involve an excessive demand on the limited 

 test facilities afforded by ship tanks and water tunnels. 



H. W. herbs 



I should like to thank the gentlemen who contributed discussions, for enhancing 

 the value of the paper and for indicating interesting related problems which fell beyond 

 the intentionally limited scope of this treatise on the basic theory. 



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