249 
on the Hambleton Hills, near Selby ; and from this locality 
it is probable that it is covered by the more recent gravel. 
Then, again, from Doncaster southwards, through Notting- 
hamshire, up to the town of Nottingham, this gravel extends 
uninterruptedly on the back of the new red sandstone, being 
spread uniformly on the surface from three to eight feet thick; 
but on very abrupt hill sides, where the new red sandstone 
rock is hard, scarcely any gravel is present. Fragments of it 
are occasionally found lying on the magnesian limestone and 
upper red marl of Notts. South of Nottingham and Derby it 
becomes intermingled with the Northern drift before described. 
The Nottinghamshire gravel is composed of fragments of 
rocks, of which no Geologist can assign the locality of the 
original rock. There are no pebbles of granite, sienite, or 
porphyry, or even mountain limestone. In speaking of the 
gravel beds of the forest of Notts, Farey says, " In all my 
examinations of this immense mass of gravel, except on the 
very surface, I did not perceive a single pebble which 
belonged to the neighbouring strata, or to any strata which 
I have seen in England. The fragments consist nearly alto- 
gether of quartz, sometimes veined, sometimes with square 
crystals embedded. The colours of the pebbles vary, and 
externally some of them appear like sandstone, but when 
broken exhibit no aggregation of particles, but are com- 
posed of pure quartz. Besides, these fragments are smaller, 
more even in size, and more spherical than either the boulders 
of the northern drift, or of the two tracts of sandstone de- 
scribed. 
The Notts gravel has evidently been derived from primary 
igneous rocks, and that by currents which have drifted in a 
north and south direction. It is also more ancient than the 
two sandstone groups before described, since at Gringley, 
Everton, and at Newington, some gravel beds of magnesian 
limestone, evidently contemporaneous with two tracts of sand- 
