Page:Transactions of the Geological Society, 1st series, vol. 1.djvu/329

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IN the account which I have now laid before the Society, of the physical structure of this interesting range of hills, I have, I fear, executed the task I have undertaken in a very imperfect manner; but I have endeavoured to avoid all theoretical speculations, and have confined myself as much as possible to a description of the facts as they present themselves. Before concluding however, I shall take the liberty of offering a few remarks on the phenomena I have described, and of examining by what theory they may, in my opinion, be most satisfactorily accounted for.

With the exception of the small bed of red sandstone on the eastern side of the Worcestershire Beacon § 29, all the unstratified rocks seem to belong to the primitive class of the Wernerian system, and in general, accord very much with the account given by Mr. Jameson in his Geognosy of the third or newest granite formation. The structure of the granite is very irregular, it is generally of a red colour, and it is found in veins that probably shoot from a great body of rock: it is frequently traversed by veins of quartz, and is not stratified. The rocks in which hornblende exists correspond with some of the varieties of primitive trap, and of sienite, as described in the same work.

The stratified rocks on the western side, are probably of very early formation, as the organic remains that are found in them are such as only occur in the oldest of the secondary rocks. The characters of the limestone quite agree with those of the transition limestone of Werner; and although the argillaceous rock does not exactly correspond with any of the transition rocks enumerated by Mr. Jameson; yet as the same organic remains are found in it, as in the limestone, and as it occurs in some places on both sides of the limestone-strata, in conformable stratification, it is very probable that both belong to the same class. The argillaceous rock may perhaps