Page:Transactions of the Geological Society, 1st series, vol. 3.djvu/354

 in the 33d and 34th Plates of the 2d. Volume of the Society's Transactions.

§ 6. In every part of the district where the slaty varieties prevail, the ends of the inclined strata as they rise to the surface become either vertical or are very much twisted. Here however the contortions appear to have taken place after the induration of the stone, for they are not in the form of curves, but are in general a succession of sharp angular twisting, with a fracture at every angle. The strata in general as they approach the surface are also very much traversed by those imperceptible cracks which make the rock, as soon as it is moved from its bed, break down into polygonal fragments of various dimensions. Hence are probably derived those loose fragments which are to be found under the surface soil all over the district where this formation occurs, and even at the summits of the highest hills. In the ravines formed by the streams in the lower parts of Dunkery beacon, there are sections of some yards in depth where nothing is seen but these fragments, imbedded in a loose red sandy soil, which is doubtless produced from the decomposition of the fragments themselves. The angular shape of the fragments is an additional proof that they have been produced on the spot, and that they are not materials transported from a distance. The most remarkable instances of these angular contortions are to be noticed in the lanes between the village of Enmore and West Monckton, and the other roads which cross the south-eastern ridges of the Quantock hills. I may particularly point out the neighbourhood of Adsborough, and the lane leading to Tarr near Kingston, where the ends of the strata of slate are covered by horizontal beds of red argillaceous sandstone and of conglomerate.

§ 7. In a country covered by vegetation, and where the rock is