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agent preparatory to this deposit. It also fill up the inequalities on the 
Paleozoic rocks, and is found in patches or ‘ pockets’ in several places. So 
far for its position, 
To what date may we assign this deposit? Though much has been 
written since the time of De La Beche respecting this old water beach, yet 
I do not think much new information has been added to what that 
eminent Geologist has already given to us. (I may except the discoveries 
of Messrs, Riley and Stuchbury of two genera of reptilia, Thecodontosaurus 
and Palewosaurus, on Durdham Down. 
Within certain limits, however, we may give the date. These limits may 
be on the one side the age of the Carboniferous limestone, on the other the 
period of the Liassic formation. So that we allow a good lengthy 
period for this formation, you will see. From the nature of its composition 
and from its position we come to the conclusion that it was the old sea or 
water beach of the Paleozoic period, and may draw this picture to our mind’s 
eye :—First, the deposition of the Carboniferous limestone in a deep sea, 
teeming with animal life, Then a gradual shallowing of the waters when 
the more sandy formation of the Millstone grit was deposited, Then a still 
further shallowing of the bottom of the sea until it became dry land and 
admitted of the wonderful growth of vegetation as exhibited during the Coal 
measure formation, with various oscillations of level and final submergence 
to allow of the formation of the Pennant sandstone; another elevation when 
the Upper Coal Measures were deposited. And then some great and 
mighty disturbance (not to be traced to the trap dyke on Mendip 
as the cause), but one of those great crumplings which corrugated 
the Old Red and succeeding formations upwards as far as the 
Coal Measures in mighty anticlinal and synclinal folds, leaving the 
surface weak and a ready prey to the incursions of the breakers 
which acted upon these exposed folds and contortions like a huge plane ; 
the softer coal beds on the anticlinal folds easily disappearing before its 
irresistible action ; the harder beds below, such as the Pennant, Millstone 
grit, Mountain limestone, and Old Red sandstone being not so easily 
disposed of, but leaving their traces in those boulders and pebbles, and 
forming the beds of Conglomerate which you trace throughout the district. 
Then followed a period of repose, which allowed of these waters to wash 
the debris of the old shore into shingle; and a still longer period 
during which the waters charged with carbonate of lime and magnesia 
gradually consolidated these beach-like accumulations ; a process now 
going on throughout our coast line. If you ask whence came the materials; 
I ask you to look towards the Mendips, and with an effort of the imagina- 
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