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The millstone grit is an important deposit in the north of England, from the Coquet to the Tyne, and on the hills between the dales of Durham and Yorkshire, from the Tyne to the Aire and the Kibble. A large mass of these rocks occupies the higher parts of Bolland; and a far larger tract extends from the Yore at East Witton, nearly S. W. to Ormskirk in Lancashire, and spreads from this line to the east, under the magnesian limestone of Yorkshire, from Masham to Aberford, and under the coal of Yorkshire, by Leeds and Bradford, to Penistone. Near this place it divides into two branches, one of which separates the limestone of Derbyshire from the coal of Yorkshire, Nottinghamshire, and Derbyshire; the other in like manner divides that limestone from the coal of Manchester and Congleton. In the south of England the millstone grit is feebly represented by the "Farewell rock" of the Forest of Dean, South Wales, and Somersetshire; but in Ireland it appears in great force on Kulkeagh, Belmore, and other mountains about Enniskillen.

The coal formation of Northumberland and Durham extends from the Coquet across the Tyne, Derwent, and Wear, to Cockfield, where it suddenly breaks off, and ends against the valley of the Tees; and no more appears between the magnesian limestone and the millstone grit till the south side of Wharfdale. Here from Aberford to Bradford it runs out, in a counterpart of the Durham recession, and then returns by Halifax and Huddersfield to Sheffield, Dronfield, Chesterfield, Alfreton and Belper, and ends near Nottingham. On the western side of the Cumbrian mountains is a narrow belt of coal formation, about Workington and Whitehaven: a small field of coal lies at the foot of Ingleborough (corresponding to one at Hartley Burn, on the South Tyne). The coal deposits of Lancashire form a considerable breadth, ranging east and west, from Manchester by Prescot and Wigan to near Liverpool, and appear to be connected underground with the coal tract of Flintshire, and, perhaps, of Shrewsbury. The detached