298 CORALS AND CORAL ISLANDS. 



those which have swept up the coast of Spain, Peru, and the 

 Sandwich Islands, would produce a complete deluge over these 

 islands. We were informed by both Grey and Kirby, that effects 

 of this kind had been experienced at the Gilbert Islands ; 

 but the statements were too indefinite to determine whether 

 the results should be attributed to storms, or to this more vio- 

 lent cause. 



But while coral islands have their storms, the region in 

 their vicinity is generally one of light winds and calms, even 

 when the trades are blowing strongly all around them. The 

 heated air which rises from the islands lifts the currents to 

 a considerable height above the island. J. D. Hague men- 

 tions that on Jarvis's and the two neighboring islands, under 

 the equator, near 180° in longitude from Greenwich, he " often 

 observed the remarkable phenomenon of a rain squall approach- 

 ing the island, and, just before reaching it, separating into two 

 parts, one of which passed by on the north, the other on the 

 south side, the cloud having been cleft by the column of heated 

 air rising from the white coral sands." 



