Page:Transactions of the Geological Society, 1st series, vol. 1.djvu/20

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8
Dr. Mac Culloch's Account of Guernsey,

This island is of a triangular shape, its extreme length being seven and a half miles, and its greatest breadth about four. Its gross circuit is twenty-one miles.

The inclination of the land bears some resemblance to that of Alderney, as it is elevated to the south, and shelves towards the north. The southern coast is bounded by high cliffs, which also extend along part of the eastern coast. The remainder of the eastern and the northern sides, consists of a series of flat bays, divided by interposed ridges of high rocks.

The whole island is readily divided by a line drawn from the Town to Pezeries. To the north of this imaginary boundary is a level tract, interrupted only by cairns and rocky hillocks. And in this tract is an inundation of about sixty years standing, which covers three hundred acres; but whether this has arisen from any change in the level of the sea, or the failure of some natural barrier does not appear. It is quite dry long before the time of low water.[1]

To the south of the line I have supposed, the country forms a higher stratum, or stair, but every where intersected by narrow vallies and deep glens, of which the direction is exceedingly various. The high cliffs which bound this southern tract are continuous, with the exception of two or three narrow coves, the mouths of small vallies intersecting the high land.

On this part of the coast there are but few detached rocks; the northern shore is beset with them.

The Island of Guernsey is almost entirely of granitic formation, the southern division consisting entirely of gneiss, and the rocks which form the northern part exhibiting various kinds of granite or granitel.

To descend to a more particular description, the rock on which

  1. Since this paper was written, the tract in question has been drained and embanked.