Page:Transactions of the Geological Society, 1st series, vol. 1.djvu/331

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of Stony-way Quarry, where the direction of the strata is from E. to W. exactly at right angles to that of the range: again, the strata nearest the range are in general quite vertical, and even in some places dip towards it, that is, eastward at an angle of 60°; and so far from the same stratified rock always occurring next the unstratified, it is in some places sandstone; in others, the argillaceous rock; and in others, limestone.

The unstratified central rocks are so much concealed, that any inferences with respect to them are liable to more uncertainty than those we are enabled to draw from the frequent exposure of the stratified rocks on the western side. But wherever they can be seen to any extent, they exhibit a great degree of irregularity, the different kinds of rock being found in large masses confusedly heaped together. The granite chiefly occurs in the lower part of the hill, and the veins of it, which penetrate the other rocks, become more slender as they ascend, in all those places where they can be distinctly traced.

Such remarkable variations in the direction and dip of the stratified rocks, can only be accounted for, on the supposition of some violent force, that has elevated them from the horizontal position in which they must have been originally deposited, and thrown them into the different situations in which they are now found; and the Huttonian Theory offers, in my opinion, a more satisfactory explanation of these phenomena, than any other with which we are yet acquainted. The situation of the granite, and the veins of it that penetrate the other rocks, in almost every part of the range, perfectly accord with the supposition of its being of later origin, and of its having been thrown up from beneath them: it is also probable that the elevation of the granite has produced the great disturb ante in the strata, which I have described. The direction of the force seems to have been from West to East, and its action appears to have ceased where the