12 CONTENTS 



CHAPTER IV 



PACK 



The velocity of the wind at sea The numerical relation 

 between velocity of wind and average height of waves 

 The relation between the velocity of the wind and 

 the velocity of the waves The connection between 

 the rate of progress of cyclones and the character of 

 the waves The effect of squalls and gusts upon 

 waves On wave-fronts in a veering wind, and on the 

 irregularity of the waves in the region of the Trade 

 winds The observed profile of waves at sea The 

 mountainous appearance of waves . . .107 



PART II 



ON THE ACTION OF SEA WAVES TO TRANS- 

 PORT SHINGLE, SAND, AND MUD 



CHAPTER V 



On the depth to which wave-agitation extends, and on the 

 transport of fine mud The action of waves to drive 

 shingle shorewards The effect of percolation to pro- 

 mote the building-up of beaches The movement of 

 sand by waves The undertow . . ... . 141 



CHAPTER VI 



On the actions which determine the 'longshore transport of 

 beach shingle On the causes which give rise to an 

 arrangement of pebbles according to their sizes along 

 the Chesil Beach and certain other beaches On the 

 production and maintenance of the Shambles sand-bank 

 near Portland The formation of patches of shingle 

 upon a sandy beach by the action of breakers . .176 



