AND THE AVON GORGE. 
181 
towards the N.W., while the Clifton and Durdham rocks dip 
down towards the S.E. There is, however, a roll in the strata 
which gives rise to a minor anticlinal, the axis of which is 
parallel to the Henburj Down, and runs a little to the N. of 
Coomb House, causing the beds of Old Eed and Lower Limestone 
Shales, which are exposed near the junction of the Henbury 
and Westbury Trym, to dip to the S.E. Were the Mountain 
Limestone beds, the Lower Limestone Shales, and the upper Old 
Eed beds, in each case, continuous over the main anticlinal, 
they would form a dome-shaped arch over the whole of the 
Westbury horseshoe. The upper part of the dome has, however, 
been entirely removed by denudation, so that only the spring of 
the arch has been left on either side. 
Turning now from the Palaeozoic rocks to the newer or 
Mesozoic beds which lie on their upturned edges, it will be 
sufficient for my present purpose to notice, first, the so-called 
Dolomitic Conglomerate, which immediately covers the older 
rocks over the greater part of the area where the Mesozoic beds 
occur. This Dolomitic Conglomerate is composed of larger or 
smaller fragments of the Palaeozoic rocks, cemented together by 
a reddish or yellowish paste. The whole forms a mass of 
considerable hardness and resisting power. On its surface 
rests the newer red Keuper Marls; and here and there, above 
this again, we find the Ehoetic beds, and the yet more recent 
Lias. 
The Dolomitic Conglomerate occupies the dip between the 
Clifton and the Durdham Downs, and may be seen in the New 
Eoad, near Proctor’s fountain, resting upon the upturned edges 
of the Mountain Limestone. It occupies the greater part of 
the area enclosed within the Westbury horseshoe, and is found 
again fringing the northern side of the Henbury and King’s 
Weston Downs. It forms on the Somersetshire side of the Avon 
the rising ground that lies to the north of the softer Old Eed 
