Jury-Law books

But it
is now admitted that this structure has been owing to movements of the earth's
crust of upheaval and subsidence, and that the flexure and inclination of the
beds has no connection with the original geographical configuration of the
district.
COAL-MEASURES.
I shall now treat more particularly of the productive coal-measures, and their
mode of origin and organic remains.
COAL-FORMED ON LAND.
In South Wales, already alluded to, where the coal-measures attain a thickness
of 12,000 feet, the beds throughout appear to have been formed in water of
moderate depth, during a slow, but perhaps intermittent, depression of the
ground, in a region to which rivers were bringing a never-failing supply of
muddy sediment and sand. The same area was sometimes covered with vast forests,
such as we see in the deltas of great rivers in warm climates, which are liable
to be submerged beneath fresh or salt water should the ground sink vertically a
few feet.
In one section near Swansea, in South Wales, where the total thickness of strata
is 3246 feet, we learn from Sir H.


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