Page:Transactions of the Geological Society, 1st series, vol. 4.djvu/25

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ago, on the Town-moor and Fenham estates, which continued to burn for 30 years. It began at Benwell about a quarter of a mile north of the Tyne, and at last extended itself northward into the grounds of Fenham, nearly a mile from where it first appeared. There were eruptions at Fenham in nearly 20 places; sulphur and sal-ammoniac being sublimed from the apertures; but no stones of magnitude ejected.[1] Red ashes and burnt clay, the relics of this pseudo-volcano, are still to be seen on the western declivity of Benwell hill, and it is credibly reported that the soil in some parts of the Fenham estate, has been rendered unproductive by the action of the fire.

At Byker St. Anthony's, and at an adjoining colliery, the Low Main coal is found at 59 fathoms below the High Main; but though the seam proved to be 6½ feet thick, the workings of it were abandoned as unprofitable; the coal being extremely fragile, and the mines very subject to the fire damp. On the south side of the Tyne, at Felling, Tyne Main, and Gateshead Fell, the quality of this coal is very much improved, and under the name of the Hutton Main, it forms one of the most valuable seams on the Wear.

I must refer to the series of sections for a more complete view of the other coal seams.

I now proceed to give a more particular account of the substances that form the coal measures.

Of the coal itself three varieties are found; the common or Slate coal, Cannel coal, here called Splint, or Parrot coal, and Coarse coal, also called Splint.

The texture of line splint is compact, the cross fracture conchoidal, and the fragments are cubical. Coarse coal is slaty in its

  1. See a paper by Dr. Lucas Hodgson, on the Salt sublimed, in the Phil. Tram. No. 130.