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crease the difficulty of reading the original record. The coast about Watchet 
is very instructive, showing pavements of limestone on the beach, the 
remains of strata once composing high cliffs of lias such as still form the 
outline of the coast. The absence of particular beds has been taken by 
some writers to imply the existence of dry land in that locality while 
such beds were in process of deposition elsewhere. Such an inference 
would, in many cases, be far from the truth. A familiar illustration 
occurs at Dundry, where the horizontal lias is abruptly broken off at each 
end of the hill, exposing an inferior formation^ Such a state of things 
could result only from denudation by water after consolidation into hard 
rock. 
The distinction is important between valleys of depression and those of 
denudation. The former are produced by the upheaval of contiguous land 
or the sinking of that forming the valley, the latter by erosive agencies, 
such as have been alluded to above. In the former case the inclination 
of the beds follows more or less the outline of the surface, in the latter the 
beds are abruptly broken off, and continued in the same plane at points 
more or less distant. 
These phenomena are frequently mixed, so as to form valleys partly of 
depression and partly of denudation. 
Alluding to the vast amount of matter removed from the surface in our 
own neighbourhood, the writer proceeded : — 
The power of the sea to remove so many thousand feet of solid rock can 
only be doubted by those who would limit the whole of the operations of 
terrestrial nature to the comparatively brief period of six or seven thousand 
years. The lapse of uncounted ages, bringing about by fixed and unerring- 
laws results upon which depends the very existence of man upon the earth, 
conveys a much more exalted idea of the Divine Author of nature than 
the instantaneous upheaval of a continent or the sudden destruction of a 
world. The destructive power of the waves upon even the hardest rock 
is seen in enormous ridges of pebbles, miles in extent, formed by the 
grinding down and rolling together of masses split from the cliffs by 
various agencies constantly in operation, and in vast collections of shingle 
bordering our shores. Even the hardest flint has been subjected to these 
grinding and polishing processes, until the beach has become a dense mass 
of flint-gravel of every conceivable degree of fineness. 
It is not necessary to suppose that a mass of rock twice the height of 
Snowdon ever stood at that elevation on the summit of our Downs. 
