Page:Transactions of the Geological Society, 1st series, vol. 3.djvu/370

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of Triscombe the conglomerate appears, and may be traced to Bagborough and from thence the whole way to Bishop's Lydeard, where sections of it are seen in the side of the road.

§ 28. I have every reason to believe that nearly the whole of the rich vale of Taunton Dean is formed of rocks of this description. Mr. De Luc[1] describes a “ red marl with blue stripes” between Blackdown and Wellington, and in the neighbourhood of Wiveliscombe he observed “ at the summit of two eminences” a conglomerate in all respects the same as the Popple Rock of Vellow, which he afterwards examined.

§ 29. Near the village of St. Michael the road is cut across a ridge, and exposes a section of conglomerate and red sandstone to the depth of 20 or 30 feet, and the same rocks are found in all the intervening vallies between the ridges of the grauwacke formation which extend from Cothelstone Lodge in a south-easterly direction. The road from Bridgwater to Nether Stowey crosses the extremities of some of the lateral branches that extend from the Quantock hills, and these are entirely composed of the derivative rocks. Near Cokehurst, at a place called Mount Radford, there are some large quarries where a very hard conglomerate is worked. In composition and alternation with sandstone it is very like the series at Lawford farm, and like that contains green patches. It occurs in thick beds which are inclined at an angle of 15°. dipping north by west. In one of the quarries I observed a slip in the beds of about four feet, and the sides of the slip were covered with a smooth coating of oxide of iron similar to a slickenside. Within a mile of Stowey, where the road turns off to Taunton, there is a sandstone which is principally white, but is in some places variegated with red spots and stripes, and containing some of those green patches so general

  1. Geological Travels, Vol. 3. §§ 1349. 1351.