350 Mr. Horner on the Geology of the 



the Quantock hills. I found there, among the rubbish, specimens 

 of malachite and of brownish-black sulphuret of copper. 



I received from Thomas Poole, Esq. of Nether Stowey, a spe- 

 cimen of an exceedingly hard and compact iron ore which had 

 been found in the Quantock hills, but in what place he could not 

 inform me. It is an oxide of an iron-grey colour and semi-me- 

 tallic lustre, with a sharp splintery fracture, and so hard as to 

 scratch glaSs easily. Its specific gravity I found to be 5.244, which 

 with its other characters brings it nearer the fer olighte of Haliy 

 than any other variety of ore. The occurrence of so rich an ore 

 in a large quantity, would be a very valuable discovery. 



§ 12. In several parts of this district there are found, as I have 

 already stated, very considerable beds of limestone which are con- 

 tained in the slate. Their occurrence in detached spots, and their 

 appearance iii the quarries where they are most extensively 

 wrought, seem to point out that they are not regular strata con- 

 formable with those of the slate above and below them. Flattened 

 spheroidal masses of the same kind of limestone are frequently 

 found, completely enveloped by the slate, and very similar to the 

 balls of clay-iron-stone in slate clay, but thinning away at the 

 edges much more than those do. I conceive that the great masses 

 of limestone occur in the same way : they have an irregular bedded 

 structure, and very often layers of slate, often of considerable 

 thickness, are interposed between the beds ; but although the 

 positions of the quarries along the eastern side of the Quantock 

 hills appear in a continuous line on the map, the great variations 

 in the bearing and dip of the strata of those quarries renders it 

 extremely improbable that the limestone of each, although very 

 similar, are parts of regular strata. These beds of limestone ap- 

 pear to be confined to the places where the slaty varieties of grau- 



