These limestone and coal measures occupy no guest breadth, and run north and south in a line nearly parallel to the ranges of greenstone and slate, being generally in contact with the former of these substances. Their extent longitudinally is from Melmerby Lane End to the Ardale water. From the latter stream southwards to the village of Murton, the red sandstone abuts for the most part against the greenstone. One exception occurs at Keisley about one mile south-east of Dufton, in the direction of Murton pike, where there is an insulated mass of stratified entrochal limestone several fathoms in thickness, and occupying superficially a little more than an acre of ground. It is inclined to the west at an angle of about B0°, and covers like a shield the abrupt end of a hill of greenstone, known by the name of Keisley pike, but insignificant in comparison with the three great pikes before described.
This limestone seems to bear the same relation to the greenstone as did the shattered coal measures and limestone before mentioned near Melmerby. It dips so rapidly that it disappears immediately at the base of the hill towards Appleby, and is at once lost under the red sandstone. [1]
We did not examine the base of the continuation of the great escarpment from Murton pike southwards towards Brough, but the concurrent testimony of many experienced miners leaves no doubt that the slate terminates a little south of Murton pike, and the red sandstone of the plain closes up against the escarpment from thence to the town of Brough.
It was stated at the beginning of this paper, that it is of the highest importance to distinguish this more recent sandstone of the plain of Carlisle from the old red sandstone or conglomerate that divides the great limestone series of Cross Fell from the slate.
- ↑ See Section, Plate 5, No.
