CURRENTS AND WHALING. 467 



stream, flowing directly on the shoal coast of Brazil, and raising the 

 level of the ocean on those banks which it endeavours constantly to 

 restore by flowing off rapidly in the opposite direction'? 



Before proceeding into the Southern Atlantic, I will recapitulate our 

 results in the Northern. 



Beginning at the equator, we find a great surface stream setting to 

 the westward across the ocean, which, passing along the coast of 

 Brazil, enters through the Windward Island passages the Caribbean 

 Sea, and thence into the Gulf of Mexico, whence the water flows in 

 the Gulf Stream, which although at first narrow, soon spreads itself, 

 crosses the Atlantic, and expends its force in mid-ocean, or at times 

 upon the British Islands. This great stream, of moderate temperature 

 on the open ocean under the equator, becomes more heated on the 

 coast of Brazil, and opposite the coast of the United States retains, both 

 in summer and winter, a temperature approaching to or often exceed- 

 ing 80°. In the mean time, another great stream sets southward, 

 along the coasts of Labrador and Newfoundland; and dividing at the 

 Banks, a branch of this follows the line of soundings off Nova Scotia 

 and the United States, while another flows beneath the waters of the 

 Gulf Stream, passes southwards, and mingles with the waters of the 

 ocean, and affects the surface temperature where it comes in contact 

 with islands and banks. The uninterrupted flow of this vast polar 

 stream is along the coast of Portugal and Spain, and a small part of it 

 flow's into the Bay of Biscay, caused by its striking upon Cape 

 Finisterre, and forms eventually the Rennell Current ; another part 

 flows into the Mediterranean, in consequence of the higher level of the 

 stream, when compared with the waters of that sea. The main branch 

 now pursues its course on the surface, until Madeira and the Canaries 

 are reached in its course, beyond which it is no longer apparent. But 

 below the surface, as shown by the low temperature of the deep-sea 

 soundings, a submarine stream pursues its way to the equator, where 

 the waters again commence the same round as before. 



In the southern portion of the space included within the above limits, 

 is an expanse of water which presents remarkable phenomena. This 

 is called by the name of the Sargasso Sea, and is noted for the quantity 

 of the aquatic plant, known as the gulf-weed (Fucus natans), that is 

 found in it. The general impression seems to be, that this space is 

 occupied by a sort of eddy, in which is deposited all the matter borne 

 by the different currents of the ocean, and that to this cause is due the 

 accumulation of the gulf-weed. It would, however, appear, that this 

 idea cannot be correct ; for, in the first place, the weed appears fresher 

 there than when drifting in the Gulf Stream and other currents, and is 



