yr F Mie VN ;* vy iw. F ==, ; 
SUBSIDENCE IN PACIFIC CORAL REGIONS. 367 
Mr. Hale remarks, after explaining the character of certain 
sacred structures of stone: “It seems evident that the con- 
structions at Ualan and Ponape are of the same kind, and 
were built for the same purpose. It is also clear that when 
the latter were raised, the islet on which they stand was 
in a different condition from what it now is. For at present 
they are actually in the water; what were once paths are now 
passages for canoes, and as O’Connell [his informant] says, 
‘when the walls are broken down, the water enters the enclo- 
sures.’” Mr. Hale, hence infers ‘“ that the land, or the whole 
group of Ponape, and perhaps all the neighboring groups, 
have undergone a slight depression.” He also states respect- 
ing a small islet near Ualan, “ From the description given of 
Leilei, a change of level of one or two feet would render it 
uninhabitable, and reduce it, in a short time, to the same state 
as the isle of ruins at Ponape.” 
In some of the northern Carolines, the Pescadores, and 
perhaps some of the Marshall Islands, the proportion of dry 
land is so very small compared with the great extent of the 
atoll, that there is reason to suspect a slow sinking even at the 
present time; and it is a fact of special interest in connection 
with it, that this region is near the axial line of greatest de- 
pression, where, if in any part, the action should be longest 
contanued. 
Among the Kingsmills and Paumotus, there is no reason 
whatever for supposing that a general subsidence is still in 
progress; the changes indicated are of a contrary character. 
IV. PERIOD OF THE SUBSIDENCE. 
The period during which these changes were in progress, 
extends back to the Tertiary era, and perhaps still farther back. 
