90 Geological Results of the Earth’s Contraction. 
e. As refrigeration went on, the centres of eruption becoming mostly 
extinct over large areas, and remaining still active over other areas of 
s 
II. Contraction, as a consequence of solidification, attended by 
a diminution of the earth’s oblateness. 
ous action therefore becoming in process of time more depressed than 
those areas that were early free (or mostly so) from such action, (ii, 
352 ; iii, 181 
d. Subsidence of the surface progressive ; or, if the arched crust re- 
sisted subsidence, a cessation, until the tension was such as to cause 
fractures, and then a more or less abrupt subsiding, (iii, 96.) 
r ; 
ual or abrupt, arising from the unequal progress of subsidence in dif- 
ferent parts, and also in early periods from extensive igneous action, 
(iii, 95, 181.) 
II. Fissures and displacements of the crust, owing to the 
contraction below it drawing it down into a smaller and smaller 
arc ; also, from a change in the earth’s oblateness. 
. . . . . u 
a. Fissures influenced in direction by the structure of the earth’s 
crust,—because of the existence of such a structure, and also because 
Pies, ph esas ei alate 
y 
* The boiling action in Kilauea, Hawaii, appears in general character, closel 
like that of boiling water. In the great lake, 1500 feet in diameter, there is ap 
ordinarily but the grum murmur of ebullition. A constant flow is see 
liquid, (well shown in the jets that move with the current,) from the hottest part, 
near the northeast side, towards the southwest part of the lake; and this hh: 
so remarkable that it was formerly accounted for by supposing that @ submarine 
stream of fire here came to the surface, and disappeared again afier being for 4 
short distance visible. 
