44 



THE OPAL SEA 



Swirhnnd 

 rings of 

 the sea. 



Swirls of 

 the air 



the other. In the process of exchange many 

 circles are drawn in the sea, and currents ver- 

 tical, horizontal, and " creeping," come into 

 existence. The waters of the tropics are 

 warmed, raised to the surface, set in motion 

 by the winds, pushed poleward, and finally re- 

 turned upon themselves in a completed ring — 

 a swirl of the sea. The waters at the poles 

 are being chilled, sent down into the depths, 

 passed on to the equator, raised up and set in 

 motion poleward again — another ring, another 

 swirl of the sea. Not here nor there, by the 

 Atlantic or the Pacific, by continental shore 

 or island archipelago is this exchange taking 

 place, but all over, everywhere, continuously, 

 unceasingly. It is a movement of the sea 

 whereby its purity and vitality are maintained. 

 Without it there would be stagnation and re- 

 sultant destruction. 



Not the currents of the sea alone but those 

 of the atmosphere are set in motion by heat 

 and cold. The scorched air lying along the 

 equatorial waters, grown volatile and capricious, 

 eddies around and around and finally forms 

 into hot winds that rise and flow out to the 

 north and south, where they meet with colder 

 winds coming down from the poles to take their 

 place. They rise above the latter flowing pole- 



