ANNOTATIONS AND ADDITIONS. 159 



( 24 ) p. 12. "Caused by the great revolving current. ' 

 In the northern part of the Atlantic, between Europe, 

 North Africa, and the New Continent, the waters of the 

 ocean are driven round in a true revolving current, or circle. 

 This general current, which, from its cause, might be 

 called a " Rotation Current," moves between the tropics, 

 as is well known, with the trade wind, from east to west. It 

 accelerates the passage of ships sailing from the Canaries 

 to South America, and makes it almost impossible to sail 

 " up stream," or in a direct line from Cartagena de Indias 

 to Cumana. This set to the west, attributed to the trade 

 winds, receives, however, in the Caribbean Sea, the accession 

 of a much stronger movement, originating in a very remote 

 cause, which was discovered as early as 1560 by Sir Hum- 

 phrey Gilbert, (Hakluyt, Voyages, vol. iii. p. 14), and 

 developed with greater certainty by Rennell in 1832. The 

 Mosambique current, flowing from north to south between 

 Madagascar and the east coast of Africa, sets on the La- 

 gullas Bank, turns on the north side of it round the south 

 point of Africa, and advances with much force up the 

 western coast of the Continent to a little beyond the equator 

 near the Island of St. Thomas. It gives at the same time 

 a north-westerly direction to a part of the water of the 

 South Atlantic, causing it to strike Cape St. Augustin, and 

 to follow the coast of Guiana to beyond the mouth of the 

 Orinoco, the Boca del Drago, and the coast of Paria. 

 {Rennell, Investigation of the Currents of the Atlantic 

 Ocean, 1832, p. 96 and 136.) The New Continent, from 



