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chain extending across the South of Scotland, from St. Abbs Head to 

 the Mull of Galloway : and it is, I believe, generally allowed, that 

 these several chains,, producing so great an impress on the phy- 

 sical character of our island, are all nearly of one age, and were pro- 

 bably all elevated nearly at the same period, before the complete de- 

 velopment of the old red sandstone. Such a parallelism cannot surely 

 be regarded as accidental, and offers, if I mistake not, a beautiful 

 confirmation of the great principle in the late Essay of M. Elie de 

 Beaumont, that mountain chains elevated at the same period of 

 time have a general parallelism in the bearing of their component 

 strata. In admitting such a principle, we must not however shut our 

 eyes to the exceptions. Mr. Weaver has shown, that the mean bear- 

 ing of the greywacke" strata in the South of Ireland is east and west ; 

 and from his descriptions they appear to have been elevated before 

 the deposit of the old red sandstone. The transition rocks of Devon- 

 shire and of a small portion of South Wales are nearly in the same 

 direction, and parallel to the principal axis of the great Welsh coal- 

 field. 



I will not detain you, Gentlemen, with my speculations on the 

 original extent of our carboniferous formations — on the different 

 periods of elevation of the coal-fields on the Bristol Channel and of 

 the great carboniferous chain of the North of England — on the diffe- 

 rent effects produced by the two systems on the range of the newer se- 

 condary groups — or on the causes by which the conflicting phenomena 

 have been brought about. — I may however be permitted to remind you 

 of the prevailing north and south bearings of the great carboniferous 

 chain, from the latitude of Derby to the border of Scotland — of the 

 great faults by which its western limits are tracked through the Peak 

 of Derbyshire — of its prolongation through an anticlinal line into the 

 high western moors of Yorkshire — and of the enormous breaks accom- 

 panying its escarpment from the heart of Craven to the foot of Stain- 

 moor. The range and effects of one part of the great Craven fault 

 have been described, with excellent illustrative sections,by Mr. Phillips 

 of York. Taking the subject up where he had left it, I have traced 

 a connected system of breaks to the foot of Stainmoor, and shown 

 that by a prolongation of the great Craven fault, producing an 

 enormous downcast on its western side, the entire carboniferous 

 zone of the Lake Mountains has been nearly cut off from the 

 central chain with which it must undoubtedly have been once con- 

 tinuous. 



Another enormous break, passing under the escarpment of the 

 Cross Fell range, meets the prolonged line of the Craven fault near 

 the foot of Stainmoor. The forces producing this double system of 

 disruptions appear to have been contemporaneous, and by their joint 

 action have thrown whole mountain masses of the carboniferous series 

 headlong into the valley of the Eden. 



We have direct proof that all the fractures above mentioned took 

 place immediately before the formation of the conglomerates of the 

 new red sandstone ; and we have the strongest reasons for believing, 

 that they were produced by an action both violent and of short dura- 



