602 REPORT — 1889. 



range over a wide area to the south of the faults, and impinge against them with- 

 out showing any tendency to approach the type of the Yoredale series. I have, for 

 purposes of classification, bracketed with them the Pendle-side grits, which are a 

 very fickle set of sandbanks, frequently dying out and coming on again at about the 

 same horizon. They may be equivalent to one of the sandstones of the Yoredale 

 beds. 



The Yoredale beds and Bowland shales I regard as synchronous on opposite sides 

 of the faults. They are each, in their respective areas, below all the thick grits and 

 above all the thick masses of limestone. 



The Carboniferous Limestone proper of Ingleborough, Pennigent, Fountains Fell, 

 &c., in the northern area, has within two miles of the faults a thickness of only 400 

 feet, including base. This may be compared with the following thicknesses within a 

 small distance of the faults in the southern area, where the following members 

 may be considered synchronous with it : — 



Feet 



Pendle-side limestone 400 



Shales, with limestone, &c 2,500 



The Clitheroe limestone 2,.'500 



Giving a grand total of 5,400 

 and this without showing a base. 



III. We are bound to find some explanation for the great discrepancies in series 

 and thickness on opposite sides of the fault, and the fact of the faults forming the 

 dividing line necessarily puts them under suspicion as having had something 

 to do with it. 



The great denudntions which are well known to have taken place in Carboni- 

 ferous rocks between their formation and the deposition of the Permian rocks have 

 rendered possible the deposit of the latter on various members of the Carbonilerous 

 System at different horizons. Befoi-e these could be effected many of the earth 

 movements must have taken place which folded and bent the Carboniferous rocks. 

 So great are these movements, so enormous the denudation, that there is every pro- 

 bability that they began their work early. 



This corroborates the view that the faults were in the main acting during the 

 deposition of the rocks ; though they probably went on before, and certainly after, 

 that period. There are other sections in the surrounding country, apparent uncon- 

 formities in the Carbonifnrous rocks, which are difficult to understand under any 

 other supposition. 



IV. Note on Reefs. — There are two distinct general types of limestone in the 

 country south of the faults : 



1. Black limestones with shaly bands, which appear for the most part to consist 

 of organisms in a state of minute disintegration, although also containing scarcer 

 complete specimens. These are nlways thinly and regularly bedded. 



2. White to grey crystalline limestones of irregular form, and less visible 

 bedding except in the mass and on the sides of the hills of which they consist. 



These latter are crammed with brachiopoda, lamellibranchs, crinoids, corals, 

 &c., many fairly perfei^t. 



The forms of these mounds, resting as they often do upon the black limestones 

 which have a very regular outcrop, and themselves presenting a sinuous outline, are 

 extremely suggestive of the idea that they are reefs growing up, on a slowly sinking 

 sea-bottom, from the li'e and death of the animals of whose remains they are com- 

 posed. Moreover, at the foot of these mounds, or reet'-knoUs as I would call them, we 

 have in many places a breccia formed of fragments of the limestone, which, I take 

 it, have been broken off' the r^ef above between wind and water, and have sub- 

 sequently been covered up by the mud of the Bowland shales and compacted into a 

 breccia. Fragments of limestone similarly consolidated occur, though more rarely^ 

 on the sides of these knolls themselves. I would call these reef-breccias. 



A rather important result might accrue if these notions are correct. 



If we could make out any particular zone in the limestones of these reefs, and 



