178 IWSTOIIV OF 



made at once spectators of a river rising and falling tliirfy feci 

 ill a few hours, must, no doubt, have felt the most extreme awe 

 and, as we are told,' a mixture of curiosity and apprehension. 

 The tides are also remarkably high on the coasts of Mulay, in 

 the straits of Sunda, in the Red Sea, at the mouth of the river 

 St Lawrence, along the coasts of China and Japan, at Panama, 

 and in the gulf of Bengal. The tides at Tonquin, however, 

 are the most remarkable in the world. In this part there is but 

 one tide, and one ebb, in twenty-four hours ; whereas, as we 

 have said before, in other places there are two. Besides, there, 

 twice in each month, there is no tide at all, when the moon is 

 near the equinoctial, the water being for some time quite stag- 

 nant. These, with some other odd appearances attending the 

 same phenomena, were considered by many as inscrutable ; but 

 Sir Isaac Newton, with peculiar sagacity, adjudged them to 

 anse from the concurrence of two tides, one from the South 

 Sea, and the other from the Indian Ocean. Of each of these 

 tides there come successively two every day ; two at one time 

 greater, and two at another that are less- The time between 

 the ai-rival of the two greater, is considered by him as high tide ; 

 the time between the two lesser, as ebb. In short, M'ith this 

 clue, that great mathematician solved every appearance, and si 

 established his theory as to silence every opposer. 



This fluctuation of the sea from the tides, produces another, 

 and more constant rotation of its waters, from the east to the 

 west, in this respect following the course of the moon. This 

 may be considered as one great and general current of the waters 

 of the sea ; and although it be not every where distinguishable 

 it is nevertheless every where existent, except when opposed by 

 some particular current or eddy, produced by partial and local 

 causes. This tendency of the sea towards the west, is plainly 

 perceivable in all the great straits of the ocean ; as, for instance, 

 in those of Magellan, where the tide running in from the east, 

 rises twenty feet high, and continues flowing six hours ; where- 

 as the ebb continues but two hours, and the current is directed 

 tu the west. This proves that the flux is not equal to th« 

 reiiux ; and that from both results a motion of the sea west* 



I Quintus Curtius. 



