DEPTH OF THE OCEAN 37 



Between and 1000 fms. about 11 million sq.m., or 26% 

 „ 1000 „ 2000 „ „ 8 „ „ 19% 



„ 2000 „ 3000 „ „ 20 „ „ 48% 



Over 3000 fathoms „ 3 „ „ 7% 



42 100 



Depth of the Indian Ocean. — ^The Indian 

 Ocean differs from the other two great ocean 

 basins in having no connection whatever with 

 the Arctic, being shut in by land towards the 

 north, and extending very httle beyond the 

 Tropic of Cancer. As regards depth it shows 

 less diversity than the Atlantic and Pacific, 

 two-thirds of its floor being covered by 

 uniformly deep water over 2000 fathoms in 

 depth. A large area less than 2000 fathoms 

 surrounds Kerguelen, and there are five deep 

 areas exceeding 3000 fathoms — four in its 

 eastern portion and one in its western portion, 

 to the south-east of Madagascar. The con- 

 tinental islands of Madagascar and Ceylon, 

 and the groups of coral islands are found in the 

 western and northern portions of the ocean, 

 while the eastern portion is practically devoid 

 of islands, the vast expanse of deep water 

 being broken only by the Cocos group and 

 Christmas Island. The Red Sea has a maxi- 

 mum depth of 1200 fathoms, and is cut off 

 from the Indian Ocean by a barrier at the 

 Strait of Bab-el-Mandeb, covered by less than 



