Page:Transactions of the Geological Society, 1st series, vol. 1.djvu/32

This page has been validated.
20
Dr. Mac Culloch's Account of Guernsey,

of Guernsey: it is equally well watered, but being better sheltered and of more extent eastward, is far more productive of trees.

The cliffs which form its northern shore are in general about an hundred feet in height, though in many places they attain twice that elevation. The whole of this side is indented by small coves and bays. The western, southern, and part of the eastern sides, are formed of shelving shores, and wide sandy bays, separated by high rocks. Sundry rocks are dispersed round these coasts. On the northern side of the island lies a large and long ridge stretching east and west, consisting of the Paternostres, the Dirouilles, and the Ecreho. The depth of the sea is more variable round Jersey than round any of the other islands, there being many banks and shoals about it.

In a general view the whole of the high and northern tract may be said to consist of granitic rock, and the southern and flatter part of the island of a mass of schistus incumbent on it. The high rocks which stretch away to sea all round Jersey seem to be of granitic formation.

The Bay of St. Ouen is a large flat sandy tract occupying the whole western side of the island, and bounded by a ridge of sienitic rock, of which species all the granite of Jersey appears to be. A few rocks of grauwacké schist are seen emerging from the sand. This coast is subject to a sandy inundation, but it does not appear to spread rapidly: no precautions are taken to prevent it.

The ridge I have been describing terminates at the Corbiere, in an assemblage of rocks which stem the current of the Atlantic tide, forming a rapid and boisterous sea about this point, well known to seamen. From here to St. Aubyn's we find a succession of points formed of the same rock, their sides being every where covered with schistus. The castles of St. Aubyn and Elizabeth are built on similar rocks.