40 On the Stratijicaiion of Matlock in Dcrlyshire, &c. 



four liine-stone rocks (exhibited in the section Plate II.) 

 which compose the hme-stone soils of this countv. Mr. 

 HuiDe (vol. XXX. page '■21 b and 276) would contend for the 

 last of these changes ; but I conceive the evidence hcie to 

 be strongly in favour of a change of the lime-stone into 

 rotten-stone, chert, and other siliceous substances, and even 

 into vegetable mould containing a larsxe portion of silex ; 

 for here the fragments of Ume-stone, the fourth in parti- 

 cular, assume that blunted nodular shape, when exposed 

 on the surface (often surrounded by a coaling of rotten- 

 stone), u'hich Mr. Hume (page 27^1) considers as evidence 

 of " loss in the primitive mass." The lower beds of the 

 first lime-stone rock, which are so much admired for the 

 beautiful assemblage of entrochi which ihcv contain, \\ hen 

 exposed on the surface by the oblique fracture of the strata 

 in particular places, as on the N.E. skirt of Masson Hill, 

 near to Salter's Way in this parish, are found among the 

 vegetable soil converted into masses of chert, with the shells 

 also changed to that substance : how much more probable 

 is it, that these chert blocks on the surface are changed 

 from lioie, than that the whole mass of lime-stone (in 

 which state these entrochi beds are always, I believe, 

 found, except near to the surface) has been phanged from 

 sdex to lime? May not silex, lime, oxygen, and others of 

 our supposed elements, all be compounds, or modifications 

 of some, perhaps, unknown substances ? and how other- 

 wise can we account for the same stratum (or rather assem- 

 blage of strata) producing concoctions or nodules, upon an 

 immense scale, of rock-salt, of gypjiun, of sienitc, of 

 slate, and perhaps of other substances, equally distant in 

 the chemist's list of njineral relations ? I allude here to the 

 strata called by Mr. Smith, and the Somerset colliers, the 

 red ground, or red earth, from that being Us prevailinii; 

 colour; in which salt will be found imbedded in Cheshire 

 and other places, gypsum in this and various other counties, 

 sienite and slate in Charnwood Forest in Leicestershire, and 

 in other places, perhaps wherever any such are met with in 

 Kngland. Hoping that I shall, ere long, see the attention 

 of practical chemists and mineralogists turnedj in right 



earnest, 



