110 
MOUNTAINS AND THEIR ORIGIN. 
chains are far more difficult to trace than the 
effects thus gradually produced. Plutonic action 
has, indeed, played the most fantastic tricks with 
the crust of the earth, which seems as plastic in 
the grasp of the fiery power hidden within it as 
does clay in the hands of the sculptor. 
We have seen that an equal vertical pressure 
from below produces a regular dome, — or that, 
if the dome be broken through, a granite crest is 
formed, with stratified materials resting against 
its slopes. But the pressure has often been 
oblique instead of vertical, and then the slope of 
the mountain is uneven, with a gradual ascent 
on one side and an abrupt wall on the other ; or 
in some instances the pressure has been so lateral 
that the mountain is overturned and lies upon its 
side, and there are still other cases where one 
mountain has been tilted over and has fallen 
upon an adjoining one. 
Sometimes, when beds have been torn asunder, 
one side of them has- been forced up above the 
other ; and there are even instances where one 
side of a mountain has been forced under the 
surface of the earth, while the other has re- 
mained above. Stratified beds of rock are occa- 
sionally found which have been so completely 
capsized, that the layers, which were of course 
deposited horizontally, now stand on end, side by 
side, in vertical rows. I remember, after a lee- 
