Page:Transactions of the Geological Society, 1st series, vol. 4.djvu/32

 of its direction a vein is found traversing Walker colliery, and crossing the Tyne at Walker near Mr. Reay's house. In the latter colliery it has been observed and described by Mr. George Hill, to whose accuracy I owe the plan given in Plate 3, and the following particulars.



The dyke is well defined, and the Plate represents its horizontal section taken at the level of the high main coal 100 fathoms from the surface. It occasions no alteration in the level of the coal measures, and the depth to which it intersects them is unknown. The dyke has been cut through by horizontal drifts in four places, from which the following sections have been taken.