292 Dr. Mac Culloch on the 
if they had been alive, were found at elevations of even an hun- 
dred feet above this. It is very certain, that the ocean could 
not have been depressed by that quantity, or rather that it never, 
could have stood an hundred feet higher than it does at pre- 
sent; so that we must conclude that this island has been ele- 
vated. Though certain geological theorists should even choose 
to imagine this, there are still sufficient proofs here of the ele- 
vation of the submarine land. It is not difficult to trace the 
causes to which this is owing, which have effected in the bottom 
of the ocean, the changes necessary for the production of these 
results: and it will be seen, that they must have depended on 
the action of volcanic powers. We shall be at no loss in dis- 
covering the actual existence of this cause in many places, but 
the following islands will afford as convenient and satisfactory 
proofs of it as any other. 
If we take the two islands of Tongataboo and Eeooa, we 
shall find that they form the first link in this chain, and one 
which is peculiarly valuable, from the proximity of these two 
tracts of coral land, Eeooa is separated from the former by a 
distance of only twenty miles. This island consists of a hill of 
considerable elevation, although its height is unfortunately not 
given in Cook’s narrative. This omission, however, is not of 
any moment for the present purpose, as the essential circum- 
stance is, that coral was observed on it at 300 feet above the 
level of the sea, continuing to near the summit. The soil above 
the coral is described as consisting of a soft yellow sandstone 
and areddish clay. Now the position of the coral here is such 
as, even in a greater degree than in the preceding instances, 
to indicate the former existence of a force which must have 
raised it to that height above the level of the sea. From the 
proximity of these two islands, it is also probable that both of 
them were raised by the same force, and at the same time ; and 
that the chief power was exerted under Eeooa, while the much 
lower island of Tongataboo was raised to so inconsiderable a 
height, comparatively, because it lay on the verge, or towards 
the evanescent margin of the expansive and elevating force. 
No other cause is adequate to the production of these effects 
