68 DESCRIPTION OF THE ROCKS 
of the cherty beds a less conspicuous but continuous thick gritstone ; 
and over all a great mass of upper shales and grits. The chert series 
becomes almost wholly plate at Tan hill, thus recalling to our memory 
the equally argillaceous beds of Nidderdale under the coal of Wogill. 
According to this view the ‘white grit,’ lying over the red beds 
or little limestone of Swaledale is equivalent to the lower or bearing 
grit of Nidderdale and Parkhead, and the ‘ millstone grit’ of Ingle- 
borougli, Penyghent, &c., a conclusion not contradicted by the section 
of Lovely seat, p. p. 50, 51. 
Passing still farther to the south we have the pebbly grit of Lovely 
seat in Dod fell and Bear’s head, at about the same distance from the 
main limestone, and undoubtedly equivalent to the millstone grit of 
Ingleborough, Penyghent, and Fountains fell. 
Feet. 
In Ingleborough the top of this grit is 260 above the main limestone. 
Penyghent 240 | and haS 240 feet ° f coaI shales *nd 
I, grits above. 
Fountains fell ... ... 150 and has 100 feet of coal shale over it. 
Wharnside ... ... 250 
Turning to the west we find the Arkendale millstone grit charac- 
teristically displayed under Coal shales and grits, along the east side 
of Mallerstang, and in Fell end, its top always three or four hundred 
feet above the main limestone. Northward it is seen in Dow crag, 
and several hills north of Stainmoor, and forms the summit of Golds- 
borough, and other craggy points about Lartington moor, having cherty 
limestones, grits, plates, and thin Coal beneath it. 
That the pebbly grit of Goldsborough is what is called the ‘millstone 
grit’ in Professor Sedgwick’s Sections of Teesdale, appears to me from 
specimens and general considerations extremely probable or almost 
certain. The following section of strata at Old Langdon mine, is taken 
from Professor Sedgwick (Camb. Trans. Vol. II.), and arranged for 
comparison with the preceding descriptions. 
