South-Western Part of Somersetshire. 365 



vative rocks occur, and at their greatest elevation as at Smokeham, 

 Crowcombe and Bagborough, but it appears to lie always above 

 them. I did not find it in any one instance covered by the con- 

 glomerates or their accompanying sandstones. 



§ 31. In the eastern part of the district near the banks of the 

 Parret below Bridgwater there is a nearly insulated hill called Can- 

 nihgton Park, totally different in structure from any other part of 

 the country described in this paper. On the north side it rises di- 

 rectly from the marsh land, with a gradual slope, to the height of 

 232 feet above the plain : on the south side it is not altogether cut 

 off from the lateral branches of the Ouantock hills. It is composed 

 of a highly crystalline limestone, of a pearl grey colour, having a 

 very close grain, and when struck, giving a ringing sound like that of 

 glass. I examined it with very great care, in order to discover 

 whether it contained any organic remains, and particularly at the 

 decomposed surfaces, and in those places where the stone was 

 bruised by the blow of the hammer, which generally detects any 

 madrepores that exist in a limestone, but I could not find the slight- 

 est trace ; and some of the quarriers who had worked there for 

 several years, told me that they had never found any thing of the 

 kind, it contains here and there contemporaneous veins of a very 

 pure white and opake calcareous spar, and the strata are traversed by 

 large veins of calcareous spar. In the latter veins the spar is dis- 

 tinctly crystallized, and in layers parallel to the sides of the vein, a 

 circumstance which points out a marked difference between them 

 and the veins of contemporaneous formation. On the north side of 

 the hill there is a vein of red sulphate of barytes, about three feet 

 thick in the widest part. This substance is not contiguous to the 

 limestone, but is accompanied on each side by a reddish brown 

 ochreous earth. Nor does the vein itself appear to intersect the 



