“i MOUNTAINS 225 
as lofty as they are now, but which were more 
or less completely levelled by the action of air 
and water, just as is happening now to the 
present mountain ranges. 
Movements of elevation and subsidence are 
still going on in various parts of the world. 
Scandinavia is rising in the north, and sink- 
ing at the south. South America is rising on 
the west and sinking in the east, rotating in 
fact on its axis, like some stupendous pendu- 
lum. 
The crushing and folding of the strata to 
which mountain chains are due, and of which 
the Alps afford such marvellous illustrations, 
necessarily give rise to Harthquakes, and the 
slight shocks so frequent in parts of Switzer- 
land’ appear to indicate that the forces which 
have raised the Alps are not yet entirely spent, 
and that slow subterranean movements are still 
in progress along the flanks of the mountains. 
But if the mountain chains are due to com- 
pression, the present valleys are mainly the 
result of denudation. As soon as a mountain 
range is once raised, all nature seems to con- 
1 In the last 150 years more than 1000 are recorded. 
Q 
