An Account of the Great Derbyshire Denudation. 29 



has yet been done. It seems to me, that there are three 

 distinct series of coal-measures, if not more, separated by 

 thick strata of red earths, or marls, not easily distinguished 

 from the upper one above the coal series, or that which un- 

 derlays the lias strata, as above mentioned, and by thick, 

 strata of limestones; each of which red earths, probably, 

 produce anomalous and local strata, or crystallized moun- 

 tain masses, in different places, where they form the sur- 

 face; and the fact of such containing no organic remains, 

 may not have arisen from their having been formed before 

 organized beings existed, as those contend who call them 

 primitive rocks, but because the circumstances proper to 

 crystallization, were unfitted to the propagation and life of 

 either animals, or vegetables; and may it not be doubted, 

 whether crystallized masses, great or small, are ever the seats 

 of reliquia ? 



The northern parts of Derbyshire, and the adjoining parts 

 of the surrounding counties, present a denudated tract, and 

 partake of this uncertainly, as to what place in the lower 

 part of the British series of strata, its strata should be re- 

 ferred : from many circumstances, I am inclined to con- 

 sider the coal-field of Derbyshire, Nottinghamshire, and 

 Yorkshire, underlaying the yellow-lime rock, as lower in 

 the series than any others of the coal-measures alluded to 

 above, and that the fourth limestone rock, which extends 

 from Castleton in Derbyshire, southward to Weaver Hill, 

 near Wooton and Ramsor in Staffordshire, is the very lowest 

 which is known in Britain, and which may account for the 

 circumstance, that the mineral veins and the strata in which 

 they occur in Derbyshire, present some phenomena, which 

 are said to occur no where else. 



I shall proceed now to describe the circumstances, under 

 which this great elevation and denudation of part of the 

 Derbyshire strata seems to have happened, which is, by a 

 series of three or four separately lifted tracts, one within the 

 other, as represented in the small sketch map annexed (PI. I.) 

 The outer or least lifted of these tracts is bounded on the 

 south by a fault, that I have distinguished by a full line, 

 where ascertained, and by slight dots where only inferred, 

 and denominated it the great Derbyshire fault, which is 

 perfectly defined from near NottinghaiTi across Derbyshire, 

 to the north side of Stone in Staffordshire (except in a few 

 places where gravel covers it), by having red marl, lying 

 nearly horizontal, on all its south side, and different strata 

 on its north side, as will be mentioned further on : the 



eastern 



