and 



166 On the Gulf Stream and Currents of the Sea. 



river descending from a higher level into a plain." Now, we 

 know very nearly the average surface breadth and velocity of the 

 Gulf Stream in the Florida Pass. We also know with a like 

 degree of approximation the velocity and breadth of the same 

 waters off Cape Hatteras. Their breadth here is about seventy 

 five miles against thirty two in the Narrows of the straits, 

 their mean velocity is three knots off Hatteras against four in 

 the Narrows. This being the case, it is easy to show that the 

 depth of the Gulf Stream off Hatteras is not so great as it is in 

 the Narrows of Bernini by nearly one half; and that consequently, 

 instead of descending, its bed represents the surface of an inclin- 

 ed plane from the north, up which the lower depths of the stream 

 must ascend. If we assume its depth off Bernini to be two hun- 

 dred fathoms, (which are thought within limits,) the above rates 

 of breadth and velocity will give one hundred and fourteen fath- 

 oms for its depth off Hatteras. The waters, therefore, which in 

 the straits are below the level of the Hatteras depth, so far from 

 descending, are actually forced up an inclined plane, whose sub- 

 marine ascent is not less than ten inches to the mile. 



The Niagara is "an immense river descending into a plain 

 but, instead of preserving its character in Lake Ontario as a dis- 

 tinct and well defined stream for several hundred miles, it spreads 

 itself out, and its waters are immediately lost in those of the 



lain •" 



lake. Why 



? It arad- 



,< 



ually enlarges itself, it is true ; but instead of mingling with the 

 ocean by broad spreading as the M immense rivers" descending 

 into the northern lakes do, its waters, like a stream of oil in the 

 ocean, preserve their distinctive character for more than tnrt 

 thousand miles. Moreover, whilst the Gulf Stream is running 

 to the north from its supposed elevated level at the south, inert i 

 a cold current coming down from the north with great veloci y- 

 Meeting the warm waters of the Gulf midway in the ocean 

 divides and runs by the side of them right back into those ver) 

 reservoirs at the south, to which theory gives an elevation sun 

 cient to send out entirely across the Atlantic a jet of warm wate 

 said to be more than three thousand times greater than the Mi 

 sissippi River ! 



Now this current from Baffin's Bay has not only no trade win s 

 to give it a head, but for a great part of the way it is below 1 1 

 surface and far beyond the propelling reach of any wind. 



