Crust Movements. 
33 
In the light of Geology the highest mountains are but 
of yesterday, and mountain ranges whose summits 
once pierced the clouds and seemed immovable and 
indestructible, have been worn down by the unceasing 
effects of disintegration and denudation. 
“ The hills are shadows, and they flow 
From form to form, and nothing stands ; 
They melt like mists, the solid lands, 
Like clouds they shape themselves and go.” 
Fig. 7. — Microscopic structure of Diorite. 
Further on we shall see that rocks now far away 
from the sea, and many hundred feet above sea level, 
were actually formed beneath the waters of an ocean. 
The changes now in operation in sea and on the land 
will help us to understand how these rocks have been 
lifted from the quiet depths of the ocean, and after- 
wards carved, into their present outlines of hill and 
dale, by running water and atmospheric agencies. 
B 2 
