264 R. T. HILL — PELE AND THE WINDWARD ARCHIPELAGO 



islands, between Cuba and Yucatan, between Haiti and Jamaica and 

 Cuba, although Cuba would be connected with the Bahama banks and 

 Florida. 



The three Windward ridges. — In studying the further meanderings of 

 the 1,000-foot submarine contour a most interesting configuration is 

 revealed. The entire mass of land and sea bottom within this contour 

 is peninsulate to South America and is still separated from the Great 

 Antilles, just south of Virgin islands and Porto Rico, by the Anegada 

 trough, a narrow canal the bottom of which is now over 6,000 feet be- 

 neath the level of the sea. Hence, in order to establish any previous 

 connection between these islands and the Great Antilles or North and 

 Central America, it will have to be proven that the Caribbean sea bottom 

 has subsided to at least this depth of 6,000 feet. 



This arrangement of the submarine banks and islands relative to 

 South America, furthermore, presents a remarkably tri-peninsulate ar- 

 rangement, consisting of three distinct elongated ridges, separated b}' 

 deeps, projecting northward from the South American continent, which 

 may be termed the Barbadian, the Caribbean, and the Aves ridges, re- 

 spectively, from east to west. 



The easternmost or Barbadian ridge extends from Tobago, Trinidad, 

 and South America northward only about one-third the total circum- 

 ference of the Windward segment. This ridge appears above the sea 

 only at the site of the island of Barbados, but is represented, as shown 

 on the contour map, by two banks which come within 100 fathoms of 

 the surface to the north of that island. 



The Aves ridge, to the westward, reveals only one tip of land above 

 sealevel. This is the small island of Aves (Bird island), about 150 sea 

 miles west of Guadeloupe, to the north and west of which there is a 

 rapid deepening of the water. Its southern extension, as indicated by 

 soundings, continues definitely nearly to north latitude 13 degrees, from . 

 which point its connection with the South American bank is indefinite, 

 owing to lack of soundings, as shown by the dotted lines on the map. 

 The Aves ridge extends more than half the distance of the entire length 

 of the Windward segment between the Anegada passage and the South 

 American coast. To the west this bank rapidly deepens in a submarine 

 escarpment of 2,000 fathoms in less than 70 miles, somewhat similar to 

 the manner in which the Barbadian ridge scarps sharply toward the 

 Atlantic basin. Nothing is known of the geologic structure of this ridge, 

 and the only way it could be determined would be by a deep boring on 

 the island of Aves. 



Of the three ridges the Caribbee, or central one, alone projects consid- 

 erably above the sealevel, and along this ridge are arranged all of the 

 present true volcanic islands. 



