Page:Transactions of the Geological Society, 1st series, vol. 1.djvu/122

 110 chain is also very near its centre. Brown-Willy, in the neighbourhood of Bodmin, is, as has been said, one thousand three hundred and sixty-eight feet above the level of the sea, while the granitic cliffs at the Lands-end do not exceed sixty or one hundred feet. It is however possible, that the neighbourhood of Craw-Mere-Pool in Dartmoor forest, not far from the eastern extremity of the chain, may be nearly as high as Brown-Willy. But it is rare to find any general rule without some exceptions: thus, according to André de Gy and Ramond, the highest points in the Vosges and in the Pyrenees are out of the central chain.

The low range of Cornwall presents a regularity in its composition, rarely found in great chains. Saussure has shewn the dissimilarity between the two opposite sides of the Alps: on the northern side, he informs us, the whole of the exterior range is composed of mountains of limestone of considerable height and extent ; on the south side, on the contrary, the schistose rocks, and even the granite reach the plains, and if limestone do exist on this side, it is of very rare occurrence, and does not form broad and continuous chains as on the northern side.

Pallas has also observed in Russia and in Siberia, essential differences between the opposite sides of the same chain of mountains. Ramond remarked the great dissimilarity between the two sides of the Pyrenean chain, the sandstones are rarely met with on the northern