Such figures as these are extremely
common in our sand-stone strata; but this is an object which I never had
distinctly observed in the alpine schisti; although, considering that
the original of those schisti was strata of sand, and formed in water,
there was no reason to doubt of such a thing being found. But here the
examples are so many and so distinct, that it could not fail to give us
great satisfaction.
We were no less gratified in our views with respect to the other object,
the mineral operations by which soft strata, regularly formed in
horizontal planes at the bottom of the sea, had been hardened and
displaced. Fig. 4. represents one of those examples; it was drawn by Sir
James Hall from a perfect section in the perpendicular cliff at Lumesden
burn. Here is not only a fine example of the bendings of the strata, but
also of a horizontal shift or hitch of those erected strata.
St Abb's Head is a promontory which, at a distance, one would naturally
conclude to be composed of the schisti, as is all the shore to that
place; but, as we approached it, there was some difference to be
perceived in the external appearance, it having a more rounded and
irregular aspect.
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