22 SKETCH OF THE GEOLOGY OF DERBYSHIRE. 
Quorndon, and keeps along the ridge that runs from that village 
towards Turnditch, where it may be very well seen at the top of the 
hill, by the Cross Hands. Hence it runs by Hulland and N. of 
Bradley to Ashbourne. All the country (except one or two spots to 
be mentioned presently) to the S. of the line now pointed out as 
running from Nottingham to Ashbourne, as far south as the Trent 
at least, and often farther, consists of one member or other of the 
new red sandstone. The first or uppermost, “the red and white 
marls, with gypsum,” keep in general to the S. of the Trent, but 
cross it at one part, and form the rock next below the surface all 
about Chellaston. Marls and sandstones, lying immediately be- 
neath the gypsum beds, stretch over all the S. of the county towards 
Burton and Uttoxeter, and are also found about Derby and Chad- 
desden ; but the country between Nottingham and Locko Park, as 
also between Kedleston and Ashbourne, is formed of the second divi- 
sion, the red and white sandstones. This rock is sometimes a deep 
red, sometimes yellow or nearly white, and sometimes mottled ; it 
is occasionally a soft, friable sand, sometimes a hard rock, frequently 
full of quartz pebbles, which, according to the state of the rock in 
which they lie, are either loose, like gravel, or compacted into a 
hard conglomerate. These pebbles have sometimes so little sand 
among them as to seem precisely like a recent gravel; but, from 
several circumstances, I believe much of this gravel to belong really 
to the new red sandstone formation. In the first place, there are 
no chalk flints or pebbles of any rock newer than the new red sand- 
stone. In the second place, it is generally found on the summits of 
hills, and it is almost invariably within the borders of the new red 
formation, into which it often passes by insensible gradations.* It 
is seen chiefly along the northern border already mentioned, and on 
the S. bank of the Trent, about Repton. The dip of the beds of 
the new red sandstone is, for the most part, insensible to the eye ; 
there is no doubt, however, that they have a gradual inclination, by 
which the one part is brought to pass beneath the other. From the 
comparative irregularity, however, of the formation, it sometimes 
happens that parts of it are wanting, and that the presence of the 
superior beds by no means absolutely warrants the existence of the 
inferior below them in particular situations. 
* This gravel, as well as much of the yellow sand which accompanies it, I 
have mentioned, in the former part of this paper, when speaking of the gravel 
about Hulland and Bradley, as diluvium, but, after examining the new red 
sandstone of Nottinghamshire, I have seen my error. 
