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stone before described, lie on the top of it. Of these three 
isolated patches, I shall only remark, that they have been 
transported by currents out of the Yorkshire and Derby- 
shire coal fields, and are derived from the magnesian lime- 
stone near Maltby, where an extensive denudation in the 
limestone terrace exhibits the devastation made. 
The materials of which the new red sandstone itself is 
composed, afford some clue to the origin of the Notts gravel, 
the bottom portion of which is in many places so perfect a 
conglomerate, containing pebbles of exactly the same size, 
that at first I was almost led to the conclusion that the gravel 
of Notts was nothing more or less than pebbles washed out 
of the subjacent new red sandstone. After repeated exami- 
nations of a large district, I found this position could 
not be maintained, and therefore the identity of the pebbles 
in the new red sandstone itself, the great similarity in size 
and absence of anything like large boulders, and the regular 
distribution, except in certain valleys, all prove their origin 
from ordinary marine action ; in fact, that they constitute 
the ancient sea bottom left by the waters which deposited 
the new red sandstone itself. 
To make my catalogue of the ranges of diluvium com- 
plete, must be named that by Everton Hills, near Bawtry, 
which extends up to Gringley-on-the-Hill, capping one of 
the highest points in Notts. This gravel is composed of 
magnesian limestone pebbles, to the exclusion of the coal 
measure sandstone rocks, and this differs from that of the Don 
and Calder tracts of gravel. There is no doubt of this, since 
pebbles of large size can be traced westwards up to Maltby, 
as before mentioned. The absence of sandstone pebbles is 
only accounted for by the abrupt terrace of coal measure rocks 
east of Rotherham. Here, suddenly, behind Rotherham, 
whence a long valley extends up to Sheffield, arises a sudden 
precipitous range of hills up to Wickersley, Ullay, and 
