202 EBB AND FLOW. 



rent force and quantity of waters. But that this should 

 take place is unavoidable. For the two great islands of 

 the old and new world have the same figures, and are so 

 stretched out as to broaden to the north, and taper to the 

 south. The seas, therefore, on the contrary towards the 

 south occupy a vast space, but to the north a small one, at the 

 back of Asia, Africa, and America ; consequently that great 

 mass of waters which is discharged from the Indian ocean, 

 and is refracted into the Atlantic, is capable of forcing or pro 

 pelling the course of the waters in a continued movement 

 nearly to the British sea, which is a part of the line described 

 northwards. But that much smaller portion of the waters 

 which issues from the north sea, and which has also a free 

 passage westwards at the back of America, is not strong 

 enough to turn the course of the waters southwards, except 

 towards that point which we mentioned, namely, about the 

 British sea. Now, in these opposite currents, there must 

 be some goal where they meet and contend, and where 

 within short space the order of advance is suddenly changed, 

 as we have said occurs about Graveling the focus of the 

 currents from the Indian and northern oceans, and that a 

 certain ocean stream is formed by opposite currents on the 

 coast of Holland has been noted by numbers, not only from 

 the inversion of the hour of the tide, which we have stated, 

 but also from the peculiar visible effect. Now if this is so, 

 we return to the position, that it must needs be that in pro 

 portion, as the parts and shores of the Atlantic extend 

 southwards and approach the Indian sea, in the same pro 

 portion the tide is prior, and early in the order of approach, 

 and in proportion as you go northwards (as far as their 

 common goal), where they are forced back by the antagonist 

 stream of the northern ocean, they are backward and 

 late. Now that this is the case, the observation of the 

 progression from the Straits of Gibraltar to the British sea 

 manifestly proves. Wherefore we think that the tide about 

 the shores of Africa is at an earlier hour than that of the 

 Straits of Gibraltar, and in reversed order the tide about 

 Norway earlier than the tide about Sweden but this we 

 have not ascertained by experiment or testimony. 



A third experiment is the following : The seas confined 

 by land on one side, which we call bays, if they stretch out 

 with any inclination from east to west, which is in the 

 same line of impetus with the true motion of the waters, 

 have heavy and powerful tides; but if in the opposite 

 direction, weak and scarcely perceptible. For the Red 



