244 
THE GEOLOGIST. 
clue may be obtained which will serve to unravel something of the 
history of those extensive denudations which have given origin to the 
curious iutercircling, and often perplexing, assemblage of mesozoic and 
ancient rocks which is presented by the geology of this part of South- 
western England, — where, although organic remains are by no means 
abundant, the fossil-collector may, at the end of a day's search, lay 
side by side the characteristic indices of life-periods separated by vastly 
remote intervals of geologic time, gathered out of not more than half- 
a-dozen quaiTies, in the space of as few miles, — and where, in a 
country that hardly deserves to be called hilly, the petrologist may 
note, in an area of the same or even less extent, an individually- 
represented range of formations, from " old red " to " lower lias." 
By such restorations of the breaks and curves in the limestone, it 
becomes at once apparent that an enormous amount of mineral matter 
has been destroyed and re-arranged. The coal-measures, with their 
coal-seams " cropping " nearly to the sui-face, and actually coming out 
to the day in places, afford perfect evidence that their collection of 
shales and sandstones were never originally discontinued at their 
present outcrop, but th&i,, on the contrary, they form only the remnant 
of a more extended tract of similar strata, long since destroyed, that 
once covered the subjacent limestone. The elevated portions of 
this rock, together with the old red sandstone, formed islands and 
l>eadlands, exposed to the action of breakers which, while they beat 
away the cliffs of the coal-measures, furnished from the harder 
strata those sub-angular shingles which, with the limestone-pebblesj 
were afterwards cemented and consolidated by a calcareous or mag- 
nesio-calcareous paste, into the dolomitic conglomerate. That this 
conglomerate was in part derived from these strata, is attested by the 
fact, that as the beds approach the coal-measures, the quantity of 
fragments of sandstone preponderates over those of limestone. It 
is also fair to assume that the softer rocks may have furnished the 
patches of red sands and marls afterwards thrown down in quiet 
places on the conglomerate. In a quan-y near Pyle, about three 
miles from Newton Nottage, a section can be observed, where 
these red sands and marls rest on the denuded surfaces of the conglo- 
merate, and are surmounted by lower lias-limestone. 
In Sir H. De La Becbe's valuable paper on the " Formation of Kocks 
4 
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