ON THE EROSION OF THE SHORES OF THE SEVERN ESTUARY. 205' 
In the Worle and Middle Hope ridges erosion is most marked 
where the interbedded volcanic series crops out upon the shore as at 
Spring Cove near Weston-super-Mare, and several spots along the 
northern shore of Middle Hope. The big thrust plane traversing 
Worle Hill from east to west strikes the coast to the north ©f Spring 
Cove, but contrary to what might have been expected, has not 
formed a plane of weakness along which any marked erosion has 
taken place. Part of the northern coast of Middle Hope is bordered 
by a raised-beach platform, and small masses of raised-beach occur 
adhering to the cliff face at a height of about 25 feet above high 
water mark at both Spring Cove and Middle Hope. 
2 . — From Clev@don to Portishead. 
At Clevedon itself the coast chiefly consists of highly resistent 
Carboniferous limestone. At a point on the coast not far to the 
south of AValton, the Holomitic conglomerate appears, and with a 
few insigniflcant breaks forms the whole coast line till Woodhill 
Bay, Portishead, is approached. It varies considerably in thickness, 
not as a rule, however, exceeding 25 feet, and while sometimes lying 
horizontally more often dips seaward at a low angle. It rests at 
first on the Carboniferous limestone, and afterwards from Walton 
northwards and eastwards on the Old Red Sandstone, the palaeozoic 
rocks in each case having an easterly or south- easterly, i.e., land- 
ward dip. It consists of blocks chiefly derived from the underlying 
palaeozoic rocks, and often large and irregular, embedded in a cement 
which is mainly calcareous in character. For much of the distance 
it forms a low platform not covered by the ordinary tides, and 
terminated at its seaward margin by a talus of big blocks. It is 
very resistent and shows little erosion. At a few spots, however, 
the Dolomitic conglomerate screen has been breached, and erosion in 
the underlying Old Red Sandstone is then rather more rapid. Some- 
times the Dolomitic conglomerate is undercut and small caves 
are formed. 
To the east of the lighthouse at Black Nore, the trend of the 
coast line alters, and then signs of erosion become considerably more 
marked. This is specially the case at Nore Park cottage, where the 
path along the coast has been swept away. The damage was, how- 
ever, entirely due to the great storm of September 10th, 1903, when 
the pier at Weston-super-Mare was swept away. Under ordinary 
conditions there is little erosion. As Woodhill Bay, Portishead, is 
approached the Dolomitic conglomerate disappears, the cliff being- 
formed only of Old Red Sandstone, and here erosion is more rapid. 
To the north of the alluvial area of W^oodhill Bay the Carboniferous 
limestone ridge of Portishead Point stands out prominently, and the 
coast onwards to the landing place is little eroded, being formed of 
hard Carboniferous limestone or Coal Measures overlain by Dolomitic 
conglomerate. 
3 . — From Portishead to Aust Cliff. 
This whdle stretch of coast as far as the southern end of Aust 
Cliff is formed of alluvium, and shows no erosion, except that there 
