SKETCH OF THE GEOLOGY OF DERBYSHIRE. 19 
vention of any considerable fault, to the S. of Mr. Gratton’s lines, as, 
for instance, the coal found between the Bramcote Hills and Staple- 
ford, and the Dale Abbey coal, the outcrop of which has been traced 
into Locko Park. Since, however, the beds rise to the S.W. it is 
evident that some great alteration must take place in that direction, 
or we should have the millstone grit rising into lofty hills to the S. of 
the coal-field, as it does on the west ; but from all the circumstances 
of the case it appears probable that the beds are depressed to the S. 
rather by several minor dislocations or changes of dip than by any 
sudden and violent disruption. In order to understand these circum- 
stances better, let us first consider the position of the overlying beds 
of the 
NEW RED SANDSTONE FORMATION. 
The magnesian limestone, the lowest bed of this formation in the 
district, and the W. boundary of which has already been marked out, 
has, where it runs through Derbyshire from Barlborough to Hard- 
wick Hall, a fine terrace* or escarpment facing to the W. and consist- 
ing of from 50 to 100 feet of the limestone, resting on a ridge of 
coal measures, which it has protected from the action of denuding 
forces. It has a very slight inclination to the E. which, in the course 
of a few miles, buries it beneath the superior beds of the red and 
white sandstone. Near Clown a portion of the magnesian limestone 
has been sunk through, and coal worked beneath it; but these ope- 
rations will not pay hereabouts until the neighbouring coal-field shall 
* Projecting portions of this terrace have been seized upon as the sites of 
the fine old mansions of Bolsover Castle and Hardwick Hall. Annesley Hall, 
likewise, is near the edge of this formation, and the character of the country 
is admirably described by Byron in his “ Dream :”— 
“ A hill, a gentle hill, 
Green, and of mild declivity, the last 
As t? were the cape of a long ridge of such, 
Save that there was no sea to lave its base, 
But a most living landscape, and the wave 
Of woods and cornfields, and the abodes of men 
Scatter’d at intervals, and wreathing smoke 
Arising from such rustic roofs ;—the hill 
Was crown’d with a peculiar diadem 
Of trees, in circular array, so fix’d, 
Not by the sport of nature, but of man.” 
