24 
DESCRIPTION OF THE ROCKS 
nearly in a parallel course on the line of the ‘ Rearing Beds’ * of 
Barrowford, and Padiham heights, and Whalley ; the millstone grit 
ranging from thence by Ortnskirk to the sea, and dipping to the 
S. E., indicates the continuation of the same combined axes of ele- 
vation, while the coalfield of Burnley lies in a parallel depression on 
one side, and Longridge fell forms its boundary on the other. 
Ry Is tone — North of the Skip ton anticlinal, and nearly parallel to 
it, is another very interesting line of elevated limestone masses, ranging 
from the limestone valley of the Aire, by Flasby, Craco, and Burnsall, to 
Greenhow hill. From Flasby towards the Wharfe, the limestone 
passes along a valley, continually expanding in area as it proceeds to 
the N. E., so as to unite with the calcareous masses of Wharfedale, 
and dipping in the most distinct manner beneath the shaly slopes 
and gritstone summits of the Rylstone and Flasby fells ; on the north- 
western side it is covered by shaly hills connected with Ryeloaf. Its 
upper beds, as seen about Craco, are of the dark laminated stone, 
so frequent in the Craven country, and below are solid gray and blue 
crinoidal rocks. In passing along its southern border, toward Burn- 
sall, the average range points E. by N., and the steep southern dip 
soon brings it, near the village of Burnsall, down to the Wharfe, which, 
here changing its course, continues on its edge as far as Appletree- 
wick. From Burnsall it extends E. by N., growing narrower continually 
to the anticlinal ridge of Nursa Knot. Between Nursa Knot and 
Greenhow hill is a depression of the limestone ridge, filled with 
shales and grits, called f dead ground.’ Its range is nearly N. N. E., 
and it is crossed by many veins. ( See the Map.) 
Greenhow . — The Greenhow hill ridge rises into two eminences, 
called Greenhow hill and Coldstones ; from both of them the beds 
dip rapidly to the north and south, (the dip diminishing as the dis- 
tance from the axis augments,) 40 °, 30 °, 20 °, 10 °. Many metalliferous 
* See Whittaker’s Craven, for an account of this local name. 
