382 ON THE AGE OP THE CANNINGTON PARK LIMESTONE. 



It will be well therefore to review shortly the facts which have 

 been accumulated by various workers, bearing on this question, and 

 so incidentally sketch roughly the history of opinion relating 

 thereto. 



Leonard Horner in his ''Sketch of the Geology of the S, "Western 

 part of Somersetshire" published in 1816 (Trans. Geol. Soc, 1st. 

 sm^s, vol. Ill, p. 365), considered the Limestone of transition 

 (Devonian) age — his words are as follows. 



" In the eastern part of the district, near the banks of the Parret, 

 below Eridgwater, there is a nearly insulated hill called Cannington 

 Park, totally different in structure from any [other [part of the 

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

 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 

 jfrom the lateral branches of the Quantock hills. It is composed of 

 a highly crystalline Limestone of a pearly 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 hammer, which generally detects any 

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

 slightest trace ; and some of the quarriers who had worked there 

 for several years, told me that they had never found anything of the 

 kind. It contains, here and there, contemporaneous veins of a very 

 pure white and opaque calcareous spar, and the strata are traversed 

 by large veins of calcareous spar. In the latter veins the spar is 

 distinctly crystallised, 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 3 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 

 limestone but to be interposed between two vertical masses. The 



