Page:Transactions of the Geological Society, 1st series, vol. 2.djvu/292

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XI. An Account of the Coalfield at Bradford, near Manchester.

By Robert Bakewell

Communicated to the Geological Society by Dr. Roget, M.G.S.

THE Coalfield which I have undertaken to describe is of very limited dimensions, extending little more than two miles in length, and about 2000 yards in breadth. (See Pl. ii. fig. 2.) The form of its area is oval. The greatest depth to which the workings have been carried is 140 yards. Ten seams of coal rise to the surface, some of which are greatly deteriorated by an intermixture of pyrites. The river Medlock flows nearly at right angles with the line of bearing of the strata and a section is exposed on its banks to a considerable distance.

Plate 2, Fig. 2.

The strata which alternate with the beds of coal are the same that are usually found under similar circumstances in Lancashire, Cheshire, and the west of Derbyshire, viz. argillaceous and bituminous shale with vegetable impressions, and ironstone sometimes in beds sometimes in nodules. There occurs also over the first coal what is more uncommon, limestone not containing I believe any organic remains; it lies in three several strata from 2 to 6 feet in thickness. It is of a reddish brown colour, and resembles the magnesia variety of Derbyshire in appearance, though it differs from it in its component parts.

The coalfield is bounded (except at its eastern extremity) by red