the coast in the neighbourhood of South Shields in the county of Durham that this formation first becomes extensive. From this point it swells into a range of low round-topped hills, and is seen stretching towards the south-west, protruding into the Coal-field, and forming an undulating line by Cleadon, Boldon, Clacks Heugh upon the Wear near Hilton castle, Painshaw, Houghton-le-Spring, Sherburn, Coxhoe, Ferry hill on the turnpike road leading from Durham to Darlington, Merrington, Eldon, Brussleton, Morton, Langton, and Sellaby, till it reaches the Tees below Winston bridge thirty miles west-south-west of that river's junction with the sea, and forty-four miles from the Tyne at South Shields. The sea coast forms its eastern boundary for twenty-seven miles and a half from the Tyne to the rocks of Hartlepool, and the red sandstone already mentioned from Hartlepool to the termination of that rock west of Croft bridge.
The same bed is afterwards continued through Yorkshire, Derbyshire and Nottinghamshire, to the neighbourhood of Nottingham, where it suddenly terminates.
Of the hills of this rock, protruded into the Coal-field, Painshaw near Lambton appears to be the highest, being probably not less than 400 feet above the level of the sea. Kirk Merrington, situated on one of these hills may also be seen to a considerable distance.
The quarry at Whitby near Cullercoats affords the geologist an excellent opportunity of ascertaining that the magnesian limestone overlies the coal-measures, and that the latter were consolidated before the limestone was deposited upon them. I shall therefore describe that curious spot.
A hollow space formed like a basin or trough is filled with the limestone.[1] The length of this from east to west is about a mile;
- ↑ Plate 4, fig. 1.
