292 
ceed next, and above them is the Plumpton Grit, about half- 
a-mile from Spofforfch. 
The Plumpton Grit is the uppermost bed occurring in this 
district. It is very coarse-grained, thick-bedded, massive- 
looking sandstone, and in the lower part is rendered quite a 
conglomerate by the great number of contained quartz 
pebbles. It is usually divided into two beds by a parting of 
shale, and measures from 150 to 200 feet in thickness. In 
some places it affords an excellent building stone ; it is of a 
deep red or purplish colour, which is probably due to the 
presence of a large amount of ferruginous matter. The 
upper beds are often flaggy, those lower down being softer 
and thicker bedded. This Grit is remarkably conspicuous 
throughout the district, from its tendency to weather into 
picturesque forms ; fine examples may be seen in Plumpton 
Park. On the road side between Plumpton, Spofforth, and 
Wetherby, large blocks frequently occm- standing alone, 
or in groups in the fields adjoining the road. The surround- 
ing soO. is generally found to be composed of the disin- 
tegrated rock. The Plumpton Grits extend beneath the 
Permian Limestone to Knaresborough, where they may be 
seen in the bank of the Nidd underlying the Permian Lime- 
stone. Under the Castle a huge boss rises up into the 
Limestone, proving the unconformability of the two rocks. 
From Knaresborough they extend northwards to Fountains, 
and form a cap to all the hills westwards to Brimham Rocks 
and Guy's Cliff, near Pateley Bridge. Brimham Rocks are 
composed of the lower members of the Plumpton Grit, and 
they exhibit the same tendency to assume all kinds of 
peculiar and extraordinary forms as those of Plumpton and 
Spofforth. 
In the stretch of country occupied by the Third Grits, 
ranging southwards from Keighley Moor, very similar sec- 
tions are obtained to those in the northern part of its area. 
