^38 THE PHYSICAL GEOGRAPHY OF THE SEA. 



Cape St. Roque is in 5° south. Now study the configuration 

 of the Southern American Continent from this Cape to the Wind- 

 ward Islands of the West Indies, and take into account also cer- 

 tain physical conditions of these regions : the Amazon, always at 

 a high temperature because it runs from west to east, is pouring 

 an immense volume of warm water into this part of the ocean. 

 As this water and the heat of the sun raise the temperature of the 

 ocean along the equatorial sea-front of this coast, there is no es- 

 cape for the liquid element, as it grows warmer and lighter, except 

 to the north. The land on the south prevents the tepid, waters 

 from spreading out in that direction as they do to the east of 35° 

 west, for here there is a space, about 18 degrees of longitude 

 broad, in w^hich the sea is clear both to the north and south. 



510. They must consequently flow north. A mere inspection 

 of the plate is sufficient to make obvious the fact that the warm 

 waters which are found east of the usual limits assigned the Gulf 

 Stream, and between the parallels of 30° and 40° north, do not 

 come from the Gulf Stream, but from this great equatorial cal- 

 dron, w^hich Cape St. Roque blocks up on the south, and which 

 forces its overheated w^aters up to the fortieth degree of north lat- 

 itude, not through the Caribbean Sea and Gulf Stream, but over 

 the broad surface of the left bosom of the Atlantic Ocean. 



511. Here we are again tempted to pause and admire the beau- 

 tiful revelations which, in the benign system of terrestrial adapta- 

 tion, these researches into the physics of the sea unfold and spread 

 out before us for contemplation. In doing this, we shall have a 

 free pardon from those at least who delight " to look through na- 

 ture up to nature's God." 



What two things in nature can be apparently more remote in 

 their physical relations to each other, than the climate of Western 

 Europe and the profile of a coast-line in South America ? Yet 

 this plate reveals to us not only the fact that these relations be- 

 tween the two are the most intimate, but makes us acquainted 

 with the arrangements by which such relations are established. 



512. The barrier which the South American shore-line opposes 

 to the escape, on the south, of the hot waters from this great equa- 

 torial caldron of St. Roque, causes them to flow north, and in 

 September, as the w^inter approaches, to heat up the western half 

 of the Atlantic Ocean, and to cover it with a mantle of warmth 



