36 THE OCEAN 



Atlantic by the Strait of Florida, in which 

 the depth is less than 500 fathoms, and with 

 the Caribbean Sea by the Yucatan Channel, 

 in which the depth exceeds 1000 fathoms. 

 The Caribbean Sea is divided into two deep 

 basins by a ridge between Honduras and 

 Jamaica, the maximum depth in the larger 

 south-eastern basin being 2800 fathoms and 

 in the smaller north-western basin 3428 

 fathoms (the Bartlett Deep) ; the passages 

 between the various islands communicating 

 with the North Atlantic are all less than 1000 

 fathoms in depth. 



The South Atlantic differs from the North 

 Atlantic in having no seas penetrating into 

 the continents and remarkably few and small 

 islands, like Ascension, Tristan da Cunha, St. 

 Helena, and Trinidad. The dominant feature 

 is the central ridge, with deep water on either 

 side, which appears to be connected by a low 

 ridge with the west coast of Africa. 



The superficial area of the entire Atlantic 

 Ocean, including the Arctic, Norwegian, 

 Mediterranean, Caribbean Seas, etc., and 

 extending southwards to the Antarctic Con- 

 tinent, is estimated at about 42 millions of 

 square miles, divided according to depth as 

 follows : — 



