draft sufficiently large. It would seem wise to do this in practice and to 

 provide appropriate ballast so that the pitch resonance occurs at or below 

 the heave resonance frequency. From Equations [37] and [38] this re- 

 quires that 



< JL 



P^ + k^-iP^ XH 



The advantage of spar-buoy-type bodies lies in their very small 

 motions in the higher frequency range. By proper design this advantage 

 may be utilized; thus very calm motions can be expected in w^aves. 



ACKNOWLEDGMENT 



The author is grateful to Mrs. Helen W. Henderson for computing 

 the results shown in Figures 2 to 6 and to Dr. W. E. Cummins for his 

 critical review of the manuscript. 



22 



