Part of Gloucestershire and Somersetshire. 321 



toward Charfield Green, and the horizontal beds gradually decline from the 

 ridge into the vale, when they become confined to the right bank of the 

 Avon ; a zone, however, of the calcareous conglomerate continues to occupy 

 the brow of the sandstone escarpment, passing Charfield Church, and sur- 

 rounding Tortworth hill, to the north-western extremity of the Park. In 

 this quarter also, detached outlying portions of lias occur, on the brow above 

 Tortworth Copse, and in the dell, which is connected with the north-eastern 

 part of Tortworth Park. 



The calcareo-magnesian conglomerate re-appears on the other side of the 

 ridge, in a small patch, within the limits of the basin ; and again, on the 

 ridge to the west, in the hollow by which the road passes from the basin to 

 Milbury heath. It forms a zone also around the northern and western 

 escarpment of that heath, and descending into the vale of Thornbury, sup- 

 ports, in conjunction with magnesian limestone, the town of that name; and 

 now occupying a considerable space, extends west, toward the Severn, form- 

 ing the base of Oldbury hill, and partly also of Aust cliff, and to the north, 

 through Moreton toward Rockhampton. It is succeeded by the new red clay 

 marl, which spreads toward the Severn on the one hand, and on the other, 

 sustaining patches of lias, composes the extended table land of Eastwood, and 

 the upper part of that of Whitecliff Park. In the whole of this expanse of 

 the vale, the disposition of the calcareo-magnesian conglomerate and suc- 

 ceeding formations appears to be nearly horizontal. 



The table lands, or stages, of new red clay marl and lias, which border 

 the right bank of the Avon at Charfield Green, and which serve as a pedi- 

 ment to the oolite escarpment, distant about two miles on the east, preserve 

 an easterly dip ; extending in their course to the north, past the eastern side 

 of Micklewood Chase, toward the foot of Nibley and Stinchcombe hills ; 

 while the red clay-marl alone, occupies the Keeper's ridge situate more to the 

 west. Between the broken escarpments and projecting feet of the two former 

 hills, a kind of amphitheatre is formed, the southern horn of which extends 

 in part toward the Keeper's ridge. Within the circuit of this amphitheatre, 

 the ground is broken into gentle eminences and depressions, exhibiting in 

 the lower parts deep soil, and in the upper, partial deposits of diluvial oolitic 

 debris, which reach down to a line, that we may conceive to be drawn from 

 Woodford Green on the south, past Newport and Breadstone, to Pyrton 

 Passage on the north. The sub-soil, to the east of the former part of this 

 line, appears to consist of new red clay-marl or lias, and in the latter, wholly 

 of lias, which last indeed prevails throughout the vale of the Severn, from 

 Stinchcombe hill on the south, past the city of Gloucester on the north. 



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