28 GWYTHER, Range nf Progressive Waves in Deep Water. 



have not been proved to remain convergent for the range 

 of values given to h, it will still remain that the amount 

 of drift necessary increases very rapidly with the height 

 of the wave, and that this will be an important factor, if 

 not the predominant factor, in limiting the height of such 

 waves in nature. 



The same conclusion will follow from the considera- 

 tion of the horizontal momentum of the fluid per 

 wave-length which will, to a first approximation, vary as 

 the square of the height of the wave, and, including the 

 further approximate terms, at a more rapid rate than this. 



