Chap. XI.] OCEAN CURRENTS. 133 



The current here observed by Captain Livingston 

 must not, without authority from actual observation, 

 be confounded with an inshore current runninof from 

 the Gulf Stream just north of the Bahamas. For 

 this latter may be an eddy-current, contained within 

 the theoretical current abc (Plate IX.), and 

 caused by the islands which divide that current into 

 two portions ; the greater portion passing south of 

 the islands, and the other portion north of them — if, 

 indeed, at any season the volume of abc be too 

 great to pass within the islands — in which case, when 

 the eddy-current exists, then the portion of the cur- 

 rent ABC, of which the eddy-current is an offset, 

 should be found running north-westwards between 

 that and the Bermudas : but this is a question to be 

 decided by observation, not only in the current itself, 

 where it is strong enough to make itself manifest, 

 but also, in order to determine its nature, whence it 

 comes and whither it goes, the actual course of the 

 •principal theoretical current or and its variations 

 must be better determined by actual observation ; 

 for shallow water, if the bottom be rock or firm 

 ground, may be little less important in determining 

 the course of the currents within any district than 

 actual land. And, indeed, by the configuration of 

 the bottom of the ocean in the neighbourhood of 

 the Bermudas, a portion of the cold water, which, 

 under the theoretical action described in Book II., 

 endeavours to pass by an under-current from the 



