Page:Transactions of the Geological Society, 1st series, vol. 3.djvu/348

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with a gradual fall to the alluvial land on the banks of the rivers Parret and Tone. On the western side of the Quantock hills the descent is very rapid into the valley; on the eastern side it is in general much less so, and a great many lateral branches stretch out at right angles to the range, shooting off, however, considerably below the summit. These sometimes terminate at a very short distance from the central ridge with an abrupt slope, at other times they descend very gradually almost to the Parret, shewing occasionally at their termination their identity in composition with the central mass.

The whole of the mountainous country I have mentioned has a smooth undulating and rounded outline, no where rugged or presenting any cliffs or precipitous faces, except on the sea shore, where sections have been formed probably by the action of the tides. The whole country is so covered by vegetation, either in the form of heath and turf on the high land, or of the more luxuriant productions of the vallies, that very few opportunities occur in the interior of ascertaining the nature of the rock on which the soil rests; but the cliffs on the sea shore afford such an ample field for studying the mineralogical structure of the country, that the scattered observations in quarries, may be more strongly relied on and more easily connected.

§ 3. From the Parret to Barnstaple Bay there is no river of any magnitude: the great watershed is to the south, and the Ex, one of the most considerable of those rivers which fall into the English Channel, rises in Exmoor Forest. The southern shore of this part of the Bristol Channel is very steep, the sea in many parts not leaving the cliffs in the lowest tides. From Minehead Point westward, the charts give 8, 9, and 10 fathoms water close in with the shore. Eastward of that point the coast is more flat, and towards the mouth of