42 
DESCRIPTION OF THE ROCKS 
Coverdale . — Descending from Pen hill in a south-eastward direction 
to Melmerby, we cross the grit of the summit, and below it a series 
of flagstones, plates, and coal, dipping E. About six hundred feet 
below the summit, Melmerby Beck falls among beds of chert (partially 
decomposed to rottenstone) about twelve feet thick ; a quarter of a mile 
to the south, and about six hundred and fifty feet below the summit, is a 
remarkable quarry of main limestone, resting on twenty-five feet of 
yellow laminated grits, and seventy-five feet of plate. The limestone 
is in a singular condition, and as full of vertical and inclined joints, as 
greenstone rocks often are. The stone is brown and ochry (as usual 
where it is changing to chert) and crinoidal. It ranges obscurely by 
some green banks to the north, and holds an indistinct course along 
the high ground to the head of the dale. Below the plate lies a flag- 
like bed of impure crinoidal limestone, then twenty feet of solid grit- 
stone, holding spirifera ; thin plates and grits follow, and next, about 
sixteen feet of yellowish gray crinoidal limestone. In the course of 
two hundred and eighty feet farther descent, the stream crosses other 
limestones, but the section is not satisfactory. 
At its junction with the river Cover, limestone in thick beds appears 
and ranges up Scrafton Beck for one hundred and thirty feet ; shewing 
prismatic structure on a grand scale, especially at the great precipice 
and remarkable cascade which terminate the cliffs. Beyond, limestone 
continues in the stream to Great Scrafton, and the total thickness here 
exposed is taken at one hundred and fifty or one hundred and sixtv 
feet. It is covered by plate. The same blue and gray limestone is 
seen from Scrafton to Coverdale Abbey, and it is the lowest rock in 
that part of the valley. In Caldbergh Beck about one hundred feet 
of this rock is exposed below the road, and above, it supports a series 
of alternating grits and plates about thirty feet thick, but, as there 
is a dislocation here, this is probably much too low a measure ; the real 
thickness is doubtless above one hundred feet. On these rests a solid 
gray limestone rock, very crinoidal and full of chert nodules. (The joints 
expand laterally into oval cavities, evidently excavated by water and 
full of clay.) This limestone is about twenty -five feet thick. Hard 
