Page:Transactions of the Geological Society, 1st series, vol. 3.djvu/369

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which are filled with a pulverulent carbonate of lime. It is very durable when used for building, and Watchet Pier has been repaired with it. The Popple rock of Vellow extends as far as Yard farm, and I observed it in the road near Quark-hill farm on the eastern side of the brook.

§ 26. At Lawford farm near Crowcombe there are some large quarries where different varieties of the derivative rocks may be seen. The conglomerate, besides its usual component parts, is accompanied by patches of a green sandy clay, similar to that in the quarries near Timberscombe, and I may remark here that these green patches are prevalent in almost all the forms of conglomerate on the south and south-east slopes of the Quantock hills.

The conglomerate at Lawford farm is covered by several beds of red sandstone, which are in general separated from each other by a layer of rounded fragments of grauwacke mixed with red earth. There are also several beds of conglomerate which are separated by beds of sandstone, lying nearly horizontal: some of the sandstone beds give more lime than any other in the quarry. This series of beds extends for some distance towards Lydeard St. Lawrence by Crowcombe Heathfield, and is succeeded near that town by red sand.

§ 27. A road is carried along the side of the Quantock hills from Crowcombe to Bagborough by Triscombe. The derivative rocks prevail all along this road, although it is at a very considerable elevation: this is the greatest height at which I found them, except in one place on the eastern slope of the Quantock hills, and near the summit of the range, at Quantock farm; where in digging a foundation there was found below the surface soil a conglomerate, consisting of rounded fragments of grauwacke cemented by a deep red clay, forming a mass of extreme hardness. A short way south