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THE NATURE BOOK 



the waves ; that nearest the water's edge 

 the waves ha\-e formed during the lowest 

 neap tides, the next during the intermedi- 

 ate tides, and the highest reaching to the 

 base of the cHffs during the spring tides. 

 These terraces are formed by the wa\-es 

 in the first place beating against and eat- 

 ing into the cliffs and undermining them ; 

 then the unsupported overhanging por- 

 tions break away and fall into the sea, 

 only to be pounded into fragments and 



carried off by the currents into deeper 

 water ; and in this way the seaward edge 

 of the land is ground and worn down to 

 a more or less uniform level. In many 

 parts of England and Scotland, traces of 

 ancient sea-terraces are to be seen inland 

 and high above the present level of the 

 sea, showing that during geological ages 

 the land has gradually risen and pre- 

 served the record of the waves and their 

 work in the past. 



F. Martin Dun'can. 



I III. WKI.LKAGE OF THE WAVES. 



