Page:Transactions of the Geological Society, 1st series, vol. 2.djvu/89

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IV. Notes on the Mineralogy of the neighbourhood of St. David's, Pembrokeshire.

By John Kidd, M.D. Prof. Chem. in the University of Oxford, M.G.S.

THE following notes are arranged under separate heads, descriptive of particular points of the country adjacent to St. David's, which were visited during a stay of a few days at that place in the summer of 1811: and for obvious reasons, such points were selected as might from description be easily referred to by others inclined to examine the same ground.

No order has been adopted in the distribution of these heads than was required for the convenience of description; for there did not on the spot, and to an unprejudiced observer, appear to be any obvious and natural chain of connexion between the several points here described.

The country round St. David's, when viewed from an eminence, presents the appearance of an extensive uneven plain, interspersed with numerous detached hills or rocky summits of an irregularly conical shape. The rocks which constitute these hills bear no marks of regular stratification; rarely support even a slight degree of vegetation; and when compared with the surrounding surface, appear as so many nuclei, about which is arranged a very curiously diversified series of highly inclined strata of a kind of slate. The constituent parts of these insulated rocks are felspar and hornblende;