140 Springs j Rivers, and the Sea. 



occasion considerable deviations fiom the 

 general rule. Thus, it is high water at 

 Plymouth about the sixth hour ; at the 

 Isle of Wight about the ninth hour ; and 

 at London bridge about the fifteenth hour 

 after the moon has passed the meridian. 

 And at Batsha, in the kingdom of Ton- 

 quin,the sea ebbs and flows but once a day 

 the time of high water being at the setting 

 of the moon, and the time of low water at 

 her rising. There are also, great varia- 

 tions in the height of the tides, according 

 to the situation of coasts, or the nature of 

 the. straits which they have to pass through. 

 Thus, the Mediterranean and Baltic seas 

 have very small elevations ; while, at the 

 port of Bristol, the height is sometimes 

 near thirty feet ; and at St. Malo's it is 

 $aid to be still greater. 



