344 ON THE FORMATION OF CORAL ISLANDS. 



feet above the level of high-water mark. But as 

 many of them are far higher, we must resort to some 

 other principle for effecting this purpose. And this 

 is the action of a subterraneous elevating force. How 

 this, and its effects, have been overlooked by all the 

 scientific navigators among these islands, it is not for 

 me to explain : how geologists in particular have 

 neglected that which offers more demonstrable and 

 tangible assistance in explaining all the revolutions of 

 the earth, than any thing which exists, they must 

 themselves say; but how it is connected with these, 

 and, more immediately, with the elevations of Italy, 

 it is my business to show. 



I have already said that Tongataboo is ten feet 

 above the high-water mark ; and even this is a greater 

 elevation than can be produced by the action of the 

 sea ; supposing too that all the surface consisted of 

 fragments, and not of perfect corals, unable to rise a 

 single inch above the highest level of the water. But 

 in many of these islands, the corals, with all their 

 characters perfect, are found at elevations many hun- 

 dred feet above this. I need not say that the ocean 

 could not have been depressed by this quantity, or 

 could not have stood so much higher than it does at 

 present. To suppose this, is for those who dispose of 

 oceans at their pleasure. The island itself must have 

 therefore been elevated. But independently of this 

 reasoning, there are sufficient proofs of such elevation 

 visible. And the causes to which this is owing, are 

 easily traced, however they may have been neglected. 

 They have acted on the bottom of the ocean, so as to 

 have effected the changes necessary for the production 

 of these results ; and they have consisted in volcanic 

 powers. In many places, there is no difficulty in 



