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 wfinter, 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 
flows 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 
