SKETCH OF THE GEOLOGY OF DERBYSHIRE. 13 
been remarked before, one set running N. and §., the other E. and 
W. one of the latter—the Gregory vein—was very remarkable for 
its richness, and has been followed for a considerable distance under 
the shale and gritstone hills to the W. at one shaft 360ft. of gritstone 
and nearly 500ft. of shale having been sunk through to reach the 
first limestone.* All the known veins are now worked out as far 
down as the toadstone, but should the difficulties attending the piere- 
ing of that rock in this situation ever be overcome, it is probable that 
mining operations will be resumed here with the same success as 
heretofore. To the E. of Ashover the millstone grit resumes its re- 
gular easterly dip, and very shortly passes beneath the coal-field. 
About five miles due S. of Ashover stands the village of Crich, on 
another still more remarkable upthrow of the limestone. This, in- 
stead of being a patch of limestone in the bottom of a valley, is a bold 
hill, overlooking all the adjoining gritstone, and commanding a mag- 
nificent prospect over the country to the S. and E. The height of 
its summit is upwards of 600ft. above the level of the Derwent close 
by, or probably between 1100 and 1200 above the sea. The lime- 
stone here forms a ridge about three miles long, and never more than 
4m. across. The northern part of the ridge is by far the highest, and 
it slopes regularly down to the S. It may be said to consist of two 
parts, the one to the N. of the village, which runs magnetic N. and 
S. the other on which the village stands, the direction of which is 
about true N.W. and S,E. There is a slight curve in the strata be- 
tween these two parts, as the beds immediately N. of the church dip 
N. while just beyond, where the lanes part, they dip 8. There are, 
therefore, two points in the ridge from which the beds dip every way, 
the pillar called the stand marks one point nearly, while the church is 
about on the other. On the N. E. and S. of the ridge, the dip of 
the beds is moderate, varying from 10° to 30°, and passing regularly 
under the shale, which, again, is overlaid by the gritstone, both dipping 
every way from the hill. On the W. side, however, there runs a 
great fault, the direction of which is 23° W. of N. which cuts through 
a portion of both parts of the ridge, and passes through the market- 
place of Crich. Just to the W. of the church it brings down the 
gritstone close to the limestone, the shale being dropped out of sight; 
while W. of the stand it cuts through the limestone, and causes its 
bed there to dip to the S.W. at an angle of 65°.4 Ata greater 
* The variations in the thickness of the toadstone here were noticed in the 
first part of this paper. 
+ This fault certainly produces a downeast to the W.; but at one or two 
