XVIII.] 



LAND AND WATER, 



31S 



accumulates in the seas of the cold northern and southern 

 regions ; but, without taking the frozen seas into account, 

 the area of the ocean is twicg as great as that of the land. 

 Moreover, though it is doubtful if the sea anywhere attains 

 a depth greater than the height of the highest mountains, 

 the average depth of the sea is greater than the average 

 height of the land above the sea ; so that, in all ways, there 

 is much more sea than dry land. 



It has been calculated that of the entire surface of the 

 earth, 144,500,000 square miles are covered by water; and 



Fig. 96. — Continental or land 

 hemisphere. 



Fig. 97 — Oceanic or water 

 hemisphere. 



as there are 52,500,000 square miles of dry land, the quantit)- 

 of water exceeds the quantity of land, nearly in the pro 

 portion that 8 exceeds 3. In other words, for every square 

 mile on the earth's surface, there are nearly three square 

 miles of water. 



Again, it may be observed that the land and water are 

 not uniformly distributed, so as to preserve the same pro- 

 portions in all parts of the world. The northern parts 

 evidently contain much more land than water, while the 



