36 THE MEDALS OF CREATION. Cuap. II. | 
strata of the respective formations that has determined the 
characters of the physical geography of England. The 
4 
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Alpine or mountainous districts, which extend north and — 
south along the western portion of England and Wales, 
from Cornwall to Cumberland, are formed by the elevated 
masses of the Silurian, Cambrian, and Metamorphic rocks. 
These are succeeded by a band of the Carboniferous and 
Triassic deposits, with a few intrusions of metamorphic and 
plutonic rocks, that stretches from the coast of Devonshire, 
through the midland counties, by Leicestershire and Derby- 
shire, to Newcastle. On the south-east of this tract, the 
Oolite and Cretaceous formations, chiefly made up of 
argillaceous and calcareous strata, constitute a diversified 
agricultural district, extending from the southern shores of 
Hants and Dorset to the coast of Yorkshire. The Wealden 
occupies the country lying between the Chalk Downs of 
Sussex, Hants, Surrey, and Kent. The Tertiary deposits lie 
in basins or depressions of the upper cretaceous rocks in the 
south-eastern and eastern maritime districts, and on an ex- 
tensive area of these beds stands the metropolis of England ; 
lastly, irregular accumulations of Drift, containmg mam- 
malian remains in some localities, are spread over the 
surface of the ancient formations, and form the immediate 
subsoil of the most fertile regions. 
