100 



THE BOTTOM OF THE SEA, 



interior, massive fragments of rock, gravel, and dirt. 

 Sometimes a mass is detached from the glacier, and, 

 floating away into the open sea, is impelled by the 

 marine currents and the winds towards the equator. 

 On the passage, the shock of one such mass striking 

 against another, the action of the waves, and the 

 melting of the surface of the ice, destroy the mass, 



V\g. 19. — Section of the Sea and the Sea-bottom in the Track of Icehcrgs 

 between Gieenlaiid and Newfoundland. 



and the debris which it carries drops from time to 

 time to the bottom of the water. In this manner, 

 icebergs perform their part in the work of sedi- 

 mentation 



The deposits formed by icebergs attain in course 

 of time to a great tliickness The Bank of New- 

 foundland appears to have been formed in this way. 



