THE DRIFT OF THE SEA. 317 



ill longitude 14^ east, and latitude 39° south, he thus writes in 

 his abstract log : 



910. " That there is a current setting to the eastward across 

 the South Atlantic and Indian Ocean is, I beheve, admitted by all 

 navigators. The prevailing westerly winds seem to offer a suffi- 

 cient reason for the existence of such a current, and the almost 

 constant southwest swell would naturally give it a northerly direc- 

 tion. But why the water should be loarmer here (38° 40^ south) 

 than between the parallels of 35° and 37° south, is a problem that, 

 in my mind, admits not of so easy solution, especially if my sus- 

 picions are true in regard to the northerly set. I shall look with 

 much interest for a description of the ' currents' in this part of the 

 ocean." 



911. In latitude 38° south, longitude 6° east, he found the wa- 

 ter at 56°. His course thence was a little to the south of east, to 

 the meridian of 41° east, at its intersection with the parallel of 

 42° south. Here his water thermometer stood at 50°, but be- 

 tween these two places it ranged at 60° and upward, being as high 

 on the parallel of 39° as 73°. Here, therefore, was a stream — a 

 mighty "river in the ocean" — one thousand six hundred miles 

 across from east to west, having water in the middle of it 23° 

 higher than at the sides. This is truly a Gulf Stream contrast. 

 What an immense escape of heat from the Indian Ocean, and 

 what an influx of warm water into the frozen regions of the south I 

 This stream is not always as broad nor as warm as Captain Grant 

 found it. At its mean stage it conforms more nearly to the limits 

 assigned it in the diagram (Plate IX.). 



912. We have, in the volume of heated water reported by Cap- 

 tain Grant, who is a close and accurate observer, an illustration 

 of the sort of spasmodic efforts — the heaves and throes — whicli the 

 sea, in the performance of its ceaseless task, has sometimes to 

 make. By some means, the equilibrium of its waters, at the time 

 of Captain Grant's passage, December — the southern summer — 

 1852, appears to have been disturbed to an unusual extent ; hence 

 this mighty rush of overheated waters from the great intertropical 

 caldron of the two oceans down toward the south. 



913. Instances of commotion in the sea at uncertain intervals 



