Page:Transactions of the Geological Society, 1st series, vol. 3.djvu/380

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Anchor, except at those places where the brooks at Little Stoke and Donniford fall into the sea. From the place where the cliffs begin to that part of the coast which is immediately below Perry Court, they are entirely composed of the lyas strata, and that is the most eastern point where the red rock appears in the cliff.

§ 40. In the whole course of this part of the shore the strata hardly ever preserve a uniform bearing or dip for the space of a quarter of a mile, but are liable to constant changes dipping in every possible direction. It would be impossible, by any description of the particular instances of disturbance, to give an intelligible representation of the extraordinary appearance of this coast on walking over it at low water: I cannot convey a better idea of it than by comparing it to the great waves of a sea suddenly consolidated. These waves are now broken in many directions, and exhibit various sections of their internal structure. That the convolutions took place when the rocks were in a plastic state is highly probable, for the curve is complete, in many cases, without a fracture. Besides these curvatures there are in many places along the cliff and particularly between Shurton Bars and Little Stoke, instances of those slips in the strata which are of such frequent occurrence in the coal districts. Sometimes these slips are only of a few inches, in general they are of a few feet, but they are sometimes so great that in a cliff of 100 feet high there is a complete change in the nature of the strata on each side of the slip; there being on one side of it a numerous alternation of limestone and slate clay strata, and on the other only slate clay with a very few thin beds of limestone. In general I found the line of the slip filled by calcareous spar, sometimes only a few lines in breadth and rarely exceeding a few inches, and in many instances as I have already noticed, I found the matter of the vein penetrating the