Page:Transactions of the Geological Society, 1st series, vol. 3.djvu/365

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spar. At Holt farm there is a vein nearly 18 feet thick, consisting of several layers so distinct that I at first conceived the mass to be a series of strata, but upon further examination I found that it was inclined at right angles to the dip of the beds of conglomerate. It is stratified not only on the great scale, but also in the internal structure, which consists of a succession of layers, having in many places a waved appearance similar to that seen in sections of recent calcareous depositions. Part of this vein consists of a mixture of white, red, and honey-yellow calcareous spar, resembling in some places cellular quartz. The quantity of calcareous matter in this conglomerate is so great that it is quarried for the purpose of obtaining lime from it. But at Holt farm, the great size of the vein renders it unnecessary for them to use the less pure conglomerate.

§ 22. In the lane leading from the town of Minehead to the church, which is situated near the eastern termination of North hill, the rock has been cut through to a considerable depth. At the first part of the ascent it is a friable red sandstone distinctly stratified, and dipping north-east by north about 15° as it were into the hill. It is almost entirely siliceous, and contains no calcareous matter, not are there any of those grey patches which generally accompany the marly red sandstone to be afterwards described. It appears to rest upon a conglomerate, that rock just appearing above ground. Continuing to ascend, this red sandstone after a short way is suddenly broken off, and is succeeded by a conglomerate which continues during the remainder of the ascent, till it meets the grauwacke formation immediately above the church: unfortunately the actual contact is not exposed. This conglomerate consists of rounded fragments of rocks identical with those found in the grauwacke formation, but without any limestone. In different parts of it there are patches of the same red sandstone that occurs in the first part of