Page:Transactions of the Geological Society, 1st series, vol. 3.djvu/386

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in determinate forms, nor any appearance of its being accompanied by rock salt.

§ 47. Near Blue Anchor the cliff is composed of a blackish grey clay, containing thin beds of a slightly effervescent argillaceous stone, and which appear to graduate insensibly into the clay. These are penetrated in all directions by numerous veins of gypsum, the thickest being parallel with the strata. The same varieties are found here as in the part of the cliff near Watchet, though not so abundantly; and although there is a very great difference in the colour of the gypseous rock near Blue Anchor, and in the mode of penetration of the gypsum, I have little doubt of its belonging to the same formation as the red rock. The strata are very much disturbed, and in one place they form a complete arch dipping south-west and north-east within the space of 50 yards.

All along the bottom of the cliffs where the gypsum is found they are hollowed out by the waves dashing upon them, and where the strata dip towards the sea the upper beds hangover a considerable way in the form of a Chinese roof. Rills of water flow over them in many places, and have worn deep channels. Dr. Maton, in his Tour through the Western Counties, when describing these cliffs, says, that “ the gypsum may be seen concreting under our eyes.” A more attentive examination would have satisfied him that there is only decay, and no production of new matter on this coast.

§ 48. The last appearance of the lyas strata on the shore is about a quarter of a mile westward of Blue Anchor, where there is a low cliff for a short space, not rising above 12 feet. But even in this limited extent the strata exhibit great disturbance. They consist of a yellow clay, containing thin strata of limestone of a cream colour, some slender veins of gypsum, and small, earthy,