68 THE OCEAN. 



and more towards tlie nortli. Thus the great river undulates here 

 and there over the seas, and according to the graceful expression of 

 Maury, waves like a pennon in the breeze. But it is probable that 

 the advance of the two opposing currents is often modified only in 

 appearance, in consequence of the superficial expansion of cold or warm 

 water. The bank of Newfoundland, that enormous plateau surrounded 

 on all sides by abysses five to six miles deep, is undoubtedly due in 

 great part to the meeting of these two moving liquid masses. On 

 entering the tepid waters of the Gulf-stream the icebergs gradually 

 melt and let fall the fragments of rock and loads of earth which 

 they bear, into the sea. The bank which rises gradually from the 

 bottom of the ocean is a sort of common moraine for the glaciers 

 of Greenland and the polar archipelago.* 



After encountering the waters of the Gulf-stream, those of the 

 arctic current cease in great part to flow on the surface, and de- 

 scend into the depths, in consequence of the greater weight which 

 their low temperature gives them. The direction of this counter-cur- 

 rent, exactly opposite to that of the Gulf-stream, is demonstrated by 

 the icebergs which the warm breath of temperate latitudes has not yet 

 melted, which travel towards the south-east, directly against the 

 superficial current, which tliey divide like the prow of a ship. More 

 to the south, we recognize the existence of this concealed current 

 only by means of sounding apparatus, the cold waters serving as a 

 bed to the warm river flowing from the Gulf of Mexico ; it descends 

 lower and lower as far as the straits of Bahama, where the thermo- 

 meter discovers it at a depth of 220 fathoms. 



Nevertheless a part of the waters of the polar current remains at the 

 surfiice of the sea ; and, gliding along the western coasts of the United 

 States as far as the point of Florida, gives to the Gulf-stream by con- 

 trast very sharply defined limits. Generally the cold water coming 

 from the Arctic Sea possesses suflicient force to compel the current 

 from the gulf to bend sensibly towards the south, and to opppose an 

 insurmountable barrier to it in the other direction. The wannest and 

 most rapid part of the Gulf-stream, which forms precisely the left or 

 w^estern side of the current, is found in immediate juxta-position to a 

 sheet of cold water, wliich spreads in an opposite direction between 

 the Gulf-stream and the American shores. This counter-current, 

 which interposes the waters of the Icy Sea between the coast of 

 Carolina and the warm river flowing from the Gulf of Mexico, bounds 



* Sec above, p. 16. 



