280 Derbyshire Limestone and Coals, are elsewhere found. 



Coal-fiekls with each other, except those helonging to the Chinch 

 Clay (mentioned in the note p. 100 of vol. xxxix., and p. 256, 

 and 257 of vol.xliii.), is to me now sufficiently made out ; and the 

 tiame wirli respect to the Uerhyshire-peak Limestone, underlieing 

 each of these several Coal-fields; and the fossil Shells in this 

 Limestone, which Mr. Sovverhy has described in the 1st volume 

 of his " Mineral Conehology," go far I think towards proving this 

 identity. 



The Authority with Geognosts, against whom they seem to 

 admit no appeal, M. Werner, has given contradictory acco\ints 

 of the place, in his system, or of the formation, to which the Der- 

 byshire-peak or mountain Limestone is to be referred, as ob- 

 served in the note onp. 2 8, of my Derbyshire lieport: so also, 

 the next greatest Authority with these Gentlemen, Mr. .lameson, 

 after stating the Toadstone interlaying these Limestones to be 

 transition (Geog. iii. p. 149), now, if we may credit Dr. Gilby 

 (p. 1S3), considers this Limestone to he first Flcelz!, see also 

 Dr. Kidd's Geology, p. 115. The Geognostic Committee on 

 my Description of these Rocks, seem to have been awed by the 

 contradictions al)ove mentioned, from venturing to pronounce, on 

 the forntatiou to which ihey should belong: but Mr. Bakewell, 

 Dr. Kidd, Dr. Pilchard, and others I believe, have since given 

 their Opinions ; and it may 1 think justly be said, that respecting 

 this, and every other particular Rock in England which has been 

 claimed by the Geognosts, as belonging to one or other of their 

 Formation*;, such a mass of cowplele contradiclioJi now appears, 

 as to render the subject quite ridiculous, and soon will render it 

 contemptible, if they persevere. 



Dr. G. seems to take it for granted (p. 1S4), tlmt what he 

 chuses to denominate the " old red sandstone," occurs luiiver- 

 sally, between the Derbyshire-])eak Limestone and the coarse 

 slate : yet, I lielieve, that a sandstone rarely occurs in this si- 

 tuation : in all the very long course of the junction of these two 

 Rocks in North Wales, which I ha\e ])articularlv mentioned in 

 p]). I(i3 to 1G.> of your last volume, I believe, 770 instance occurs 

 of snr.dsione in this sitnatio'i : in like manner, in examining 

 lately, the entire circuit of the Limestone* Rock, which underlies 

 the shallow basin of C'oal-measures around Thornhill in Dum- 

 fries-shire, a circuit of near 30 miles, a thick whin or basaltic 

 rock, and not sandstone, is everywhere found, interposed, be- 

 tween the Limestone and the coarse Slate. I cannot find that 



* Ir. the t;ir-iitLT part of its range, tiiis llock proves uiitii i'di; the lime- 

 Luriiei's purpose, and is called Du^^ti-; aslmppcns also iu Aiifilebca. to the 

 SW of Ceinr, anrl moic locaDy, iii the quarries S of llie j^iea't Pontcjssjllte 

 aqueduct, asulotlicr places. 



Mr. 



