110 
there is good reason to tliink that the rock forms an outlier, 
the beds dipping on all sides gently into the hill. 
To the north of this outlier we find a second thick bed of 
similar sandstone, which can be traced passing into the hill- 
side beneath the Houghton Common Rock ; this I have called 
the Brierley Rock. It is seen on the north around the village 
of Hemsworth ; it then passes beneath the measures which 
lie between it and the Houghton Common Rock, and it 
reappears on the south-west side of the basin at the village 
of Brierley. On the west it abuts against a fault parallel to 
our boundary fault. It may be followed to the south-east for 
some distance both from Hemsworth and Brierley; but 
on both the north-east and south-west sides of the basin 
its escarpment becomes after a while more and more 
indistinct in this direction, and at last ceases to be recog- 
nisable. The rock, therefore, probably dies out towards the 
south-east. 
Such calculations as the data allow us to make, 
give the distances of the bases of these two rocks above 
the Barnsley Coal to be 560 yards and 680 yards re- 
spectively. 
The district we have next to turn to lies to the north of 
a probable fault which runs from near Hemsworth Station 
nearly parallel to the line of the Great !N"orthern. Railway. 
In it the only conspicuous features are formed by two thick 
sandstone beds. The upper may be seen in the cutting of the 
Great Northern Railway a mile-and-a-half north-west of 
Hemsworth Station, and may be traced thence northwards 
through Taylor Wood up to our boundary fault. The lower 
sandstone is the rock so largely quarried on Ackworth Moor 
Top ; the bed seems here to be at its thickest, for though it 
may be followed both to the north and south of this spot, it 
grows less marked in the first direction, and seems to thin 
away altogether in the second. 
