THE WINDS 



Ocean, but the term can be applied to other seasonal 

 winds. Independently of their value in bringing rain to 

 countries which would otherwise degenerate into deserts, 

 they are, like the trades, useful for navigation. In sailing- 

 ship days, mariners would plan their voyages to take 

 advantage of them, and even in the early days of steam- 

 ships their captains would take them into account and 

 often achieve the feat of running before them : to the dis- 

 comfort of their passengers, but with good effect on the 

 times of their voyages. 



The world's oceans and winds are in close sympathy. 

 They form an alliance in which it might seem that the 

 oceans are the sleeping partners, and the winds the active 

 ones who do nearly all the work regarding the transport 

 of countless millions of tons of waste matter to the sur- 

 faces of the sea, and the movement of innumerable clouds 

 which discharge themselves into the oceans. 



Winds are forever moving over the world in numerous 

 directions, and currents of air are continually ascending 

 and descending, and in all that they do, they are helping 

 the sea to conquer the land, not merely in its erosions of 

 the world's coasts, but also in its reception of millions 

 upon millions of tons of surface soil and dust carried into 

 it by the winds. But the ocean contributes a vital share 

 to the partnership. It gives its surface moisture to the 

 winds, which carry its evaporations far over the world's 

 land surfaces. In exchange for the solid matter that it 

 receives from the land it returns a small percentage of its 

 surface water; the partnership is thus not entirely one- 

 sided. Nevertheless, the sea has the best of the bargain, 

 for the land does not retain the sea's water contributions 

 for long. 



The erosive action of winds can be extremely serious. 

 To take but one example : The winds continually blow- 

 ing across the southern half of Australia are removing 

 hundreds of thousands of tons of top-soil every year. 

 Extending northwards from the Mallee district of north- 



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