BOTTGERS CHABT. 31 



is succeeded by the comparatively sliallow space of 

 the Gulf of Mexico, and the sea in the neighbourhood 

 of the Greater Antilles and the United States. 



A great extent of shallow sea is also to be observed 

 extending from Nova Scotia to the east of the Great 

 Bank of Newfoundland, and to the coast of Labrador. 

 It is by this route, as all know, that the polar ice 

 and icebergs descend towards the Gulf Stream, the 

 warm current of which causes them to melt, and do- 

 posit in the bed of the sea the debris of the land from 

 which they had drifted away. 



5. Tlie ]\Iediterranean and the Black Seas — Chart of Bottgcr. 



The Mediterranean and the Black Seas are of no 

 great depth. The plummet seldom reaches 12,000 

 feet, and not more than half that depth in the greater 

 part of their extent. The waters of the Mediter- 

 ranean, however, cover many great valleys. The 

 deepest is surrounded by the shores of Tripoli, Greece, 

 and Italy. It is separated by a narrow chain of 

 mountains from another great valley, which occupies 

 the space bounded by the Grecian Archipelago, Asia 

 Minor and the coasts of Syria and Egypt. 



Beginning at the Straits of Gibraltar, we find the 

 submarine soil highest near the coasts of Spain and 

 Morocco. At the western end of the strait, the depth 



