64 DESCRIPTION OF THE ROCKS 
Passing from Nidderdale to the north we reach the widely wrought 
collieries of Colsterdale, and have the following series of beds, as ob- 
served in Brown beck colliery on the general surface of moorland, 
including Witton fell. The same beds occurred in the Witton fell 
collieries, now no longer worked. 
Middle grit ? Strong gritstone of Agra crags 
Lower plate and 
flagstone 
Ochry soft sandstone 
Platy grit 
Bluish laminated grit and plate 
Gray sandstone ... 
Blue soft stone ... 
Gray sandstone ... 
Gray and blue stone 
Platy grits and alternations 
Solid grit rock 
Platy grit 
Solid gray sandstone rock ... 
Dark plate 
Hard gray laminated stone 
Coal ... 
Ft. In. 
0 7} 
1U i 
1 2 > 
1 3 ) 
Ft. In. 
51 6 
1 9 
4 6 
63 0 
4 11 
33 
7 
6 
5 
34 
21 
0 3 
Limestone and coal 
group 
' Hard gray stone with round balls 
Crinoidal limestone 
Hard yellowish cherty stone 
Blue plate 
Coal (15 to 18 inches) of WogiU-and 
Tfope scar 
18 9 
15 0 
6 0 
5 0 
1 4 
The coal of Colsterdale, Trope, and Wogill, is identical with that of 
Scrafton, but lies above that of Parkhead, which corresponds to the 
lower Nidderdale or Ramsgill, and Greenhow coal. 
In Great W hern side we have five hundred feet of plates, flagstones, 
and solid grits, above the lower fnillstone grit and coal, of Parkhead. 
The uppermost rock in Great Whernside may be referred to the upper 
plates and grits of Nidderdale. The lower grit ranges down Coverdale 
