DAVIS : EXPOSED SECTIONS. 
109 
series of sandstones occupying the surface around Ack worth, 
which are described in the Memoirs of the Geological Survey 
as the " Ackworth Rocks." Near the village the}^ have been cut 
through by the River Went, exposing the shales beneath. A tribu- 
tary of the Went running between East Hardwick and Went 
Hill also exposes the shales in a similar manner, the Ackworth 
Rock capping the slight elevation of East Hardwick on the west, 
and on the east immediately underlying the Permian Limestone 
escarpment forming the western boundary of Went Hill to Went- 
bridge and for some distance south of the deep channel formed 
by the river. This sandstone on the Geological Survey Map, 87 
N.E., is indicated as a "Lower Red Sandstone and Marl," and 
considered a member of the Permian and Magnesian Limestone 
series. Later researches, as already stated, have proved that 
this is not the case, but that it is a sandstone of the coal measure 
epoch which has been stained by the superincumbent limestone a 
reddish or purplish colour. South of the Went, the whole of the 
district round Badsworth and South Kirkby is composed of shales 
with occasionally thin beds of raggy sandstone. Westwards of 
Hemsworth a sandstone occupies the surface extending to 
Brierley, called the " Brierley Rock ;" and south-eastwards forming 
a semicircular patch, is an expansion of the Houghton Common or 
Pontefract rock, reaching to Clayton-in-the-Ciay. Near Cudworth 
the line of railway cuts through some of Chevet Rocks, which 
along with the Oaks Rock are considerably developed towards 
Barnsley. 
After the deposition of the coal measures a long interval 
elapsed before the Permian Limestone formation was deposited. 
The coal measures which had been evenly and uniformly accumu- 
lated above the millstone grit rocks over the surfaces now known 
as Lancashire and Yorkshire became subject to great displace- 
ment by subterranean agencies ; the hills dividing the two 
counties were forced into existence, and during the process the 
whole country, east and west of the gre'at central line of elevation 
