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NATURE FOR ITS OWN SAKE 



Dancing 

 jet*. 



The size of 

 coast waves. 



lower part of the wave is not able to keep up 

 with the upper part, the top is shot violently 

 forward, and having no base to rest upon, 

 breaks and falls upon the beach in spray. The 

 cause of the dancing upward of the waves under 

 the deep-based cliff will now be apparent. The 

 base of the wave, meeting with no marked 

 friction, moves as fast as the top and strikes 

 the rock beneath the surface. The whole wave 

 rebounds against the wave following it, and a 

 push upward of the water in vertical points or 

 dancing jets is the result. There is no other 

 way for the water to move. 



It will not have escaped the notice of the most 

 casual observer that the waves breaking upon a 

 coast follow each other more closely than upon 

 the open sea. The friction upon the waves as 

 they reach shallow water the drag upon the 

 bottom is also responsible for this. The front 

 ones cannot move so fast as the rear ones, and 

 there is a closing up of the ranks sometimes 

 a doubling or tripling of the waves. This at 

 times results in the waves along shore being 

 smaller than on the open sea, and again, in 

 times of storm, it may result in their being 

 larger. Certainly a storm on a rocky coast will 

 throw the breaker-crest higher than upon open 



