Subject to Law 



ocean -waters rise higher and sink lower than 

 at other times. 



When Sun and Moon are so placed with re- 

 gard to the Earth, that they exercise their pull 

 in a cross direction, Neap Tides result, — that 

 is tides which have small ebb and flow. In 

 this case the sun hinders instead of helping the 

 moon, and the moon does the same for the sun, 

 each tending to counteract the work of the 

 other. 



Connected with and partly caused by the rise 

 of the tide Is the curious phenomenon known as 

 a *' Bore " — a single high wave, moving onward 

 like a wall of water, with great rapidity and a 

 roaring noise. More usually this belongs to a 

 river, and thus it has not much connection with 

 the subject of the ocean ; but it is also some- 

 times seen in sharply narrowing estuaries or 

 ocean inlets. 



To the inhabitants of a flat and unprotected 

 country, bordering on river or estuary, the bore 

 is often a thing of terror, for its advent is un- 

 certain and abrupt, and in its upward rush it 

 sweeps everything before it. The entering of 

 such a wave into the Severn is an almost daily 

 event, and it reaches often a height of many feet. 

 Bores are usual, too, in the River St. Lawrence, 



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