268 A Geological Description of the Parish of Portishead. 



two rocks, bringing tlie old red again into view, and turning up the edges 

 of the horizontal strata. On descending the road towards the church, the 

 old red exhibits itself under a more decided character, and lies in thick 

 beds, whose dip and bearing however it was not found practicable satis- 

 factorily to estimate. 



Near the bottom of the lane, just above the highest cottage, is a bed of 

 quartz conglomerate, not dissimilar in appearance to that described as 

 cropping out in the cliff at Woodhilj bay. 



The old red does not extend very far on either side of the lane, being 

 exchanged on the north for the horizontal rocks, and supporting on the 

 south the carboniferous limestone. At tlie bottom of the lane it is covered 

 up with dolomitic conglomerate, which extends a little to the east of the 

 Portishead and Weston in Gordano road, between which and the marsh 

 its lower boundary extends beyond the limits of the present district. 



If, at the last-described bifurcation, we had taken the road to the right, 

 we should have observed the old red, covered up with an occasional patch 

 of dolomite, to extend down the road nearly to Capenor Court, terminating 

 abruptly towards the west in dolomite ; and tovvai ds the east underlying 

 the carboniferous limestone. Below Capenor Court the carboniferous 

 limestone is very well seen, dipping 20° E. N. E. and forming the steep 

 and rocky hill between Capenor and the church, the skirt of which is 

 covered up, as usual, by dolomite. It should be observed, tiiat the car- 

 boniferous limestone of this hill is of a buff colour, and differs in appear- 

 ance, though not in fossils, from the ordinary rock ; but that it closely 

 resembles the beds at the battery. Leaving Capenor Court by the road 

 to the south, we shall observe the dolomite about us ; and on striking off 

 towards the top of Portishead Down, across the fields, we shall find the 

 dolomite to form the spur of tlie down above us, and to ascend for some 

 way up a small comb, above which an occupation road leads to the down. 



Upon reaching the head of the comb, we find ourselves in a small valley, 

 the sides of which indicate the limits of the lower limestone shale, which is 

 exposed in one or two quarries along its extent, and is seen to be highly 

 inclined, and in some places much contorted. The crest of Portishead 

 Down is formed by the intermediate beds between the shale and old red ; 

 and the elevated ridge on the south-east is composed of carboniferous 

 limestone, overlying the shale, and dipping at angles of from 70° to 80°, 

 towards the south-east. 



All tliese points are remarkably well seen in a valley at the south-western 

 extremity of the ridge, down which a road winds ; and if, after having passed 

 the most picturesque part of the ravine, we turn off along a foot-path to 

 the left, we shall see in several places, along the skirts of the wood, the 

 carboniferous limestone appearing on our left, and covered up by the dolo- 

 mitic conglomerate on our right, towards the marsh ; and if we follow this 

 footpath into the Weston in Gordano road, we may continue upon the dolo- 

 mite, as far as the mill from whence we set out. 



