126 The Rev. D. Williams's Proofs that the Devonian 



parallel of Camelford, along the surface of the beds, would 

 describe a long low undulation ; if, however, we follow the 

 coast, we observe, about three furlongs north of Bossinny, the 

 Coddon Hill grit exposed under all the circumstances of a 

 valley of elevation, underlying the killas on either flank of the 

 valley, both of them dipping to the north on the north side, 

 and south 15^ W. on the south side. The place is marked 

 " Mill" on the Ordnance map, and bears W. 10° N. from 

 South Tregear Down, from hence they undulate to Boscastle, 

 as in the section No. 1. 



But let us return to Boscastle, to the bottom of the town 

 near the harbour. We stand upon beds of the culm-mea- 

 sures, and observe distinctly the same beds before us and be- 

 hind us inclining at a low angle to the north; from hence we 

 take our departure up the steep road which leads to Camel- 

 ford ; happily several cuttings have been made to facilitate the 

 ascent. Examining the slates as we ascend, we at length observe 

 the black or dark slates behind us to have lost much of their 

 carbonaceous character, and to have assumed a deep blue, a 

 bluish and then a grayer aspect ; and these again (at about 

 where we leave the houses) to pass into a pale green subcry- 

 stalline killas, which continues for about 200 yards up the 

 cutting to the top of the hill, and thence accompanies us the 

 entire way to the slate quarries of Delabole and Tintagel. 

 Ascending the hill just mentioned, we do not observe any va- 

 riation in the angle or direction of the dip 10° N., or any evi- 

 dence whatever of a fault or shift of the beds, and are con- 

 strained to conclude that the killas and culm-measures, which 

 appear as if trancjuilly piled one upon the other, have been 

 quietly elevated by the same movements and at the same 

 times. 



Again, before we leave the houses at the top of the town, a 

 road branches off to the eastward, leading to Minster and 

 Lesnewth. It is hardly necessary to premise that the northern 

 margin of the killas hereabout describes an irregular line, 

 sometimes considerably waved, at others indented, or over- 

 lying the culm rocks in rather long spurs; following this road 

 to Minster, at about a quarter of a mile, we meet with a small 

 cutting about five feet deep. I collected and numbered the 

 specimens on the spot, and ascertained pretty accurately the 

 thickness of their beds. They were as follows : — 



Pale green killas 2 feet. 



Slate, glossy blue, and dark blue 1 foot. 



Black culmy schist, sometimes soiling the fingers 2 feet. • 

 So that here we have a fine feather edge of the killas, resting 

 nearly flat on the floriferous or culm rocks. 



