THE AGE OF THE PENINE CHAIN. 



the west of the Penine Chain. Such pebbles could only have been 

 derived from the wear of a central tract of land composed of carboni- 

 ferous rocks, and their presence clearly indicates that not only had the 

 Penine Chain come into existence in pre-Permian times, but also that 

 denudation had supervened to such an extent that rocks so low down as 

 the Mountain Limestone were then laid bare in that range. 



V. Though the Bunter Sandstone of West Notts and East Derby- 

 shire contains numerous fragments of carboniferous rocks, limestone, 

 chert, and millstone grit, no debris of Permian rocks is to be found in 

 that or any other member of the Trias. This fact, though negative, and 

 therefore inconclusive, would seem to show that the Percnians were 

 formed subsequently to the elevation of the Penine Chain, and con- 

 sequently were not uptilted so as to be exposed to denudation on the 

 flanks of that range in Triassic times. 



VI. The absence of Permian outliers at any distance west of the 

 Magnesian Limestone escarpment, taken in conjunction with the absence 

 (of fragments) of Permian rocks in, and their overlap by, the Triassic 

 deposits of the neighbourhood, indicates that the original margin of the 

 Magnesian Limestone waters did not he very far west of the present 

 escarpment. 



VII. There is no similarity either in character, thickness, or succession 

 of the Permians on the opposite sides of the Penine Chain. In Lancashire 

 and Cheshire the Lower Permians are represented, according to the 

 Government surveyors, by a mass of unfossiliferous red sandstone, 

 estimated to attain a maximum thickness of 1,500ft., (near Stockport.) 

 while the Upper Permians of South Lancashire consist of from 100 to '250 

 feet of red calcareous marls with thin bands of earthy limestone aud 

 gypsum. Omitting from consideration the " Lower Permian Sandstone," 

 the true horizon of which seems somewhat doubtful, we still find 

 a very dissimilar grouping of the Permians on the two sides of the 

 Penine Chain. In Lancashire and Cheshire we look in vain for any 

 deposit answering to the highly characteristic marl slates of the north- 

 east of England, nor do we find any considerable masses of dolomite 

 comparable with those of Durham and Yorkshire. From Notts to 

 Northumberland the Marl Slates, Magnesian Limestone, and Upper 

 Marls are severally distributed, but on passing across England from Notts 

 to Lancashire — a much less horizontal distance — we find that we 

 cannot positively recognise one of these members of the Zechstein. 

 This marked dissimilarity is in part, at least, to be accounted for by 

 the presence of an intervening land barrier ; this barrier was no doubt 

 the range of high land known as the Penine Chain. 



We may then, I think, without hesitation, conclude that the eleva- 

 tion of the Penine Chain took place before the Permian era, or at any 

 rate prior to the deposition of the Permian rocks of the North of England. 



I have already drawn your attention to some of the results of the 

 elevation of this important range. Its influence on the distribution of 

 the rock masses of the neighbourhood, which began in early Permian 

 times, persisted into the Keuper epoch. Having in pre-Permian times 

 acquired the elevation and stability of an arch, this great anticlinal still 

 maintains that relative superiority to the surrounding country that has 

 justly earned for it the epithet " the Backbone of England." Though 

 marine denudation has planed away its top, while sub-aerial decay has 

 cut deeply into its framework, the great hardness and extreme durability 

 of its more axial rocks have enabled this ancient mountain chain to resist 

 those agents of destruction so successfully that it still forms a broad 

 elevated tract of country, while rearing its loftier peaks from two to three 

 thousand feet above the level of the sea. 



