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Page:Transactions of the Geological Society, 1st series, vol. 1.djvu/206

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194
Mr. Aikin on the Wrekin, and on the

being occasion to put down a drainage pit, its place was fixed upon about one hundred and fifty yards further in the dip of the work than a pit which had already been sunk through the regular coal strata to the depth of about one hundred yards: when the new pit was begun, the workmen were surprised on finding themselves in the sandstone; they nevertheless persevered till they reached the depth of fifty yards, when the work was abandoned, the entire sinking having been in an uniform bed of red sandstone.

The town of Newport may be considered as marking the apex of an acute angle formed by one line passing to the S.W. through a trap-formation including the hills of Lilleshull, the Wrekin, the Lawley, Caer Caradoc, and Ragleath; and by another line running nearly due south and coinciding with the western edge of the red sandstone. The stratified rocks included within this angle rise to the west or north-west, and of course have their dead level or line of horizontal bearing between N. and S. and N.E. and S.W. being inflected towards the one or the other of these points apparently by their proximity to the sandstone or to the trap. They are also much more closely accumulated on each other, and are generally elevated at a higher angle, as they advance from the south to the north: thus, the same succession of strata, which occupies a line of between four and five miles in the parallel of Caer Caradoc, is contracted within a space of less than three quarters of a mile in the parallel of the Wrekin.

I now proceed to give a brief detail of the several strata and beds, beginning with the most recent.

The independent coal-formation is found immediately adjacent to the red sandstone from Wombridge in the parallel of Wellington to Coal-port on the Severn, a length of about six miles; its greatest breadth is about two miles. It rises west a little to the north at an