1 30 Mr. Hopkins's Remarks on Farey's Account of the 



2. The period of the disturbance or disturbances which 

 produced the present dislocations of the superficial strata 

 must have been long posterior to that of the production of the 

 toadstone, since the beds of toadstone have suffered exactly 

 the same dislocation as the limestone. 



3. One and the same bed of toadstone pervades the whole 

 district N. of Middleton Moor (by Youlgrave), the limestone 

 above it, occupying the surface, being of contemporaneous 

 formation in every part of it*. There is no valid evidence of 

 the existence of a second bed beneath. 



4. In the portion of the district S. of Middleton Moor, I 

 have not yet obtained evidence perfectly conclusive as to there 

 being one or two beds of toadstone. If there be two, it would 

 seem almost necessary that the lower one should be contem- 

 poraneous with the one above described, the upper one being 

 probably of very limited extent. 



5. The principal transverse or N. and S. fault is that al- 

 ready described as extending from Copt Hill to the S. of 

 Chelmerton, the strata on the E. of it being elevated. Many 

 other partial ones, however, exist along the eastern side of the 

 district from Bakewell to Cromford and Wirksworth, and 

 along the north western boundary. In the former, where the 

 dip is easterly, the E. side is almost without exception the 

 most elevated ; and in the latter, where the dip is westerly, the 

 W. side is the elevated one. Of the south-western side I 

 cannot yet speak in detail. 



These faults are not distinguished, like the longitudinal E. 

 and W. faults, by strict rectilinearity and persistency in their 

 direction. They are rather formed of a number of partial 

 faults, the directions of which are nearly parallel, and of which 

 the extremities do not exactly meet. 



6. The great E. and W. faults are numerous, and their 

 common direction coincides with the mean dip of the strata. 

 They are remarkable for their rectilinearity and parallelism 

 to each other. 



7. Each of these longitudinal faults is accompanied by one 

 of those fissures which are become so well known to us as mi- 

 neral veins, this fissure being generally though not universally 

 on the elevated side of the faulty to which they are near and 

 parallel. 



Conversely, each of the large rake veins, about fifteen or six- 



* It was only on renewing my investigation in the spring that I came to 

 this conclusion. Before I had examined Farey's third basset, I took for 

 granted its continuity, and therefore regarded it as the complete basset of 

 the first toadstone, and consequently the limestone beyond it to the W. 

 as the second. 



