OCEANIC DISCOVERIES. 663 



coasts with that of their parallels of latitude, as the long con- 

 tinued action of the movement of the sea between the tropics 

 from east to west. 



When the Admiral on his fourth and last voyage discovered 

 the inclination from north to south of the coasts of the conti- 

 nent from Cape Gracias a Dios to the Laguna de Chiriqui, he 

 felt the action of the violent current which runs N. and 

 N.N.W., and is induced by the contact of the equatorial cur- 

 rent with the opposite dyke-like projecting coast line. 

 Anghiera survived Columbus sufficiently long to become ac- 

 quainted with the deflection of the waters of the Atlantic 

 throughout their whole course, and to recognize the existence 

 of the rotatory movement in the Mexican Gulf, and the pro- 

 pagation of this movement to the Tierra de los Bacallaos 

 (Newfoundland) and the mouth of the St. Lawrence. I have 

 elsewhere circumstantially considered how much the expedi- 

 tion of Ponce de Leon, in the year 1512, contributed to the 

 establishment of more exact ideas, and have shown that in a 

 treatise written by Sir Humphrey Gilbert between the years 

 1567 and 1576, the movement of the waters of the Atlantic 

 Ocean from the Cape of Good Hope to the banks of New- 

 foundland, is treated according to views which coincide al- 

 most entirely with those of my excellent deceased friend, 

 Major Rennell. 



At the same time that the knowledge of oceanic currents 

 was generally diffused, men also became acquainted with those 

 great banks of sea- weed, (Fucus natans,) the oceanic meadows 

 which presented the singular spectacle of the accumulation of 

 a social plant over an extent of space almost seven times 

 greater than the area of France. The great Fucus Bank, the 

 Mar de Sargasso, extends between 19 and 34 north latitude. 

 The major axis is situated about 7 west of the island of 

 Corvo. The lesser Fucus Bank lies in the space between the 

 Bermudas and the Bahamas. Winds and partial currents 

 variously affect, according to the character of the season, the 

 length and circumference of these Atlantic fucoid meadows, for 

 the first description of which we are indebted to Columbus. 

 No other sea in either hemisphere presents an accumulation of 

 social plants on so large a scale."* 4 



* Examen crit., t. iii. pp. 26 and 66-99; and see also, Cosmos, p. 313. 



