Page:Transactions of the Geological Society, 1st series, vol. 3.djvu/353

 chief objection to the word. To those however who may give to it the theoretical meaning which this word implies in the Wernerian system, I must again point out the alternations of quartz rock, and of a clay slate, with beds of limestone full of organic remains. The clay slate cannot be distinguished from that of a primitive country.

§ 5. A reference to the accompanying map will serve better, than any description to shew the extent of country occupied by this formation: it remains for me to point out some of those circumstances connected with it which appear to be worthy of more particular notice.

The north hill which extends along the shore from Minehead to Porlock, forming a very hold and precipitous coast, affords the best opportunity of studying this grauwacke formation. At Greenaley point, about a mile westward of Minehead, there are very lofty sections where the alternations of the different varieties may be distinguished, and where there are also very good examples of these curvatures, which, in this formation, are of such frequent occurrence. Strata that run for some distance in a horizontal line suddenly turn up into a vertical position, at other times they assume the form of an arch or a succession of great curves. It is hardly necessary to say that these rocks could not have been deposited in the forms they new exhibit, and it is pretty evident that the flexures must have taken place while the rock was in a plastic state, for there is no fracture at the bendings, nor any interruption to the continuity of the mass. Similar curvatures are to be seen at Hurstone point, the western extremity of North hill. These appearances are so well known that drawings of them are unnecessary: they are very analogous to those observed by Mr. Conybeare in the same rocks on this coast, some miles westward, and represented