Page:Transactions of the Geological Society, 1st series, vol. 3.djvu/355

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so liable to partial irregularities, it is exceedingly difficult to form any general conclusions as to the bearing and dip of the strata. Every geologist must have observed that the external shape of a hill is not always a certain guide in determining the bearing of the strata that compose it, and that in many places other causes must have operated in producing the external forms which the earth now exhibits. I believe however that the general bearing of the strata in question may be stated to be between east and west, and that the dip is more generally to the south than to the north.

§ 8. In the ridge which terminates at North Petherton, there are at Binfords some very large quarries where the gradation of one variety of rock into another may be seen. In the lower part of one of the beds there is an accumulation of rounded masses of an oblong shape, varying in size from a few inches to several feet, in the direction of what may be termed their longest diameter. Their internal structure is often identical with the adjoining strata of grauwacke, but they more frequently consist of a succession of thin concentric layers, these layers being of the same substance with the strata, but separated from each other by a thin coating of oxide of iron, having the shining lustre of hematite. The smaller of these masses more nearly resemble a large mytilus than any other shape to which I can compare them, and the larger of them preserve nearly the same form. They appear to have been consolidated while the rock in which they are imbedded was in a soft state, for the surface of the bed on which they rest is covered with the moulds of those that have been removed.

§ 9. Near Ely Green in the side of a combe called Dibbles, towards the summit of the Quantock hills, I observed a variety of slate differing considerably in appearance from any I met with in the district except in one other spot. It is of a bluish green