46 Ueply to Mr. Farey's Geological Observations. 



stone grit and shale grit near Rurnsal, on the river Wharf, 

 in the same manner as the metalliferous limestone of Der- 

 hyshire. All the ablest geologists that I have conversed 

 with, who have exan)ined the lime rocks of both counties, 

 are convinced of their similarity, and had Mr. Farey visited 

 the country without any prejudices from his particular 

 theory, I am salisfied he would have formed the same con- 

 clusions. 



As Mr. Farey has written so much and so frequently ou 

 what he calls a great Derbyshire Fault, winch extends from 

 the south side of NoUiugham to Ashburn in Derbyshire, 

 and from thence in a circuitous path to Macclesfield in 

 Cheshire, and further to the north, where he ceases to trace 

 it ; I am sure geologists will be obliged to him to inform 

 them where he has*actually found this fault 'in situ' in 

 any pari i'rom Nottingham to Ashburn ? what is its exact 

 breadth ? whether it be merely a slip, or whether it be 

 filled vtith mineral matter? and of what kind ? He will 

 also inform them how the limestone has passed over or 

 under this fault, so as to appear again with veins of lead ore 

 at Breedon and in other situations on the south side of the 

 Trent. It will scarcely satisfy the curious to be told that 

 these lime rocks are mere anomalous masses, though it 

 may be an easy method of dismissing a difficulty which 

 destroys the very existence of Mr. Farey's Derbyshire fault. 

 1 am inclined to believe that Mr. Farey has written so 

 much in sober seriousness respecting this great phceno- 

 nienon, that he earnestly believes in its reality; but 1 pre- 

 sume that he has the singular satisfaction of enjoying this 

 opinion undivided. I never have met with any one resi- 

 dent near its supposed course, or who has paid attention 

 to the subject, who believed that it had any other existence 

 than in the n)ind of the discoverer, who has given to it a 

 local habitation and a name. With respect to the existence 

 of what Mr. F. calls the Zigzag Fault, the most intelligent 

 coal workers that 1 have conversed with who have pits in 

 the vicinity are not disposed to admit its existence. The 

 western side of Derb^ shire adjoining Cheshire and part of 

 Staffordshire is much broken by faults ; but 1 have seen no 

 proof offered that any one of these faults extends over a 

 considerable tract of country. On the southern side from 

 Nottingham to Derby, the very existence of such a fault 

 as Mr. Farey describes has no where been proved in 

 any part that I am acquainted with. The loose sand rock 

 and gravel of Nottinghamshire and Derbyshire appears to 

 have beeu thrown over the surface in extensive patches 



which 



