Page:Transactions of the Geological Society, 1st series, vol. 3.djvu/383

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grauwacke and quartz similar to what is found in the surrounding country. On crossing the brook the cliffs soon begin to rise again, and the lyas strata appear at the bottom covered by about 12 feet of this gravel, which becomes gradually thinner towards the west. The lyas strata continue as far as the headland on the eastern side of Watchet Harbour, and at the place of junction great confusion takes place.

§ 48. It was in this place that walking across the line of bearing of the strata at low water I discovered them in that position which leads me to think that the appearances of the red rock alternating with the lyas may be deceptions. Fig. 1. Pl. 24. is a ground plan of this part of the coast, the dark line representing the cliffs, and the faint lines the strata; a a being the limestone and b b the red rock. I found at A and B strata of lyas dipping towards the same point, and conformably with the dip of the strata of red rock at C. I therefore expected that as in going from A to B, I should cross the prolongation of the strata of red rock from C, although the ends of the strata were not much raised above the sand, I might obtain distinct evidence of the red rock alternating with the lyas: but instead of this I found the strata in the position represented in fig. 2. which is a vertical section in the line A B of fig. 1.


§ 44. The whole of the headland is composed of strata of the red rock, dipping rapidly towards the north in the cliff, but as they extend out to sea they undergo great changes, dipping to every point of the compass and with every variety of inclination. In some places they sweep round, forming a portion of a great circle with the dip of the strata towards the centre, as the lyas strata are seen to do in the eastern part of the coast. Here the grey parts of the red rock, which in general only appear as