Page:Transactions of the Geological Society, 1st series, vol. 1.djvu/131

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of Devonshire and Cornwall.
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Kit-hill is situated farther in the interior of the country than the small hill above Ivy-Bridge. The distance of the latter from the coast is, in a direct line, scarcely nine miles, whereas Kit-hill is at least thirteen.

In proportion as the valley of the Erme rises, it continues to open, insomuch, that at three miles and some furlongs from Ivy-Bridge northward, the river is no longer confined in a narrow channel, but flows over a plain gently inclined towards the south.

This mountain plain, at Harford church, which is six hundred and fifty-eight feet above the sea, is entirely granitic. We leave the grauwacke behind, about half a mile nearer the sea, and in ascending the valley of the Erme, the point of termination is very distinctly seen, particularly on the left bank. At the junction, there are veins or shoots of granite of different lengths and breadth, and they appear to penetrate into the grauwacke; The two rocks are certainly contiguous, and in immediate contact the one with the other.

The grauwacke near its termination loses its slaty character, as may be seen on the sides of the hill above Ivy-Bridge, where it attains nearly the same height as in the last mentioned place.

The primitive rock of this district is a true granite, composed of felspar, quartz, and mica, and the crystals of felspar are sometimes two or three inches long.

From Harford church the country assumes quite a bare and alpine appearance, presenting a vast plain extending beyond the