Page:Transactions of the Geological Society, 1st series, vol. 1.djvu/162

 150 point, and it is so nicely balanced, that a child may move it with the greatest ease, although it is of a very considerable size. The interesting observations of Mr. Playfair on this subject, render it unnecessary for me to say any thing further concerning it.

With regard to the nature of the granite itself, the crystals of felspar in it are numerous, very large, and often in an earthy state: the rock is crossed in many places by felspar veins of considerable length: black tourmaline, in large and small crystals, is also very common in the mass: taken in its whole extent, this granite is rough and uneven, furrowed on the surface, and may be said to bear very marked proofs of the hand of time.

At the point which may properly be called the Land's-end, the cliff is abrupt, but not more than fifty or sixty feet high. It is composed of granite, presenting very remarkable appearances, and which might be taken for the work of art, as well as the logan stones. In some places there are shafts which look as if they had been cut with the chisel, in others, regular equidistant fissures divide the rock into horizontal masses, and give it the appearance of a collection of basaltic columns: in other places again, there are complete arches under which the waves of the sea roll—physical and undeniable proofs of the combined action of time and external agents.

The Islands of Scilly, nine leagues distant from the Land`s-end, are said to be granitic, as well as the Islands of Jersey, Guernsey and