Kendall : The Brockrams of the Vale of Eden. 307 



quartzite can be matched precisely by the rocks which succeed 

 the Basement conglomerate on Roman Fell. At one time the 

 writer regarded the Rhyolites as indisputable evidence of the 

 exposure of the Borrowdale rocks of the Cross Fell Inlier to 

 denudation during Permian times, but, while this still seems 

 to be the most probable explanation of their presence in the 

 Upper Brockram, it is possible that they could have been derived 

 from the Carboniferous Basement conglomerate in which, at 

 Swindale Beck, a few such pebbles occur. 



Setting aside the Rhyolite pebbles, there is still a body of 

 evidence which seems to warrant deductions of very great 

 interest. The facts to be explained are — the occurrence in the 

 Lower Brockram of a practically pure gathering of Carboniferous 

 Limestone, while the Upper Brockram contains a very high 

 percentage of rocks from the very base of the Carboniferous 

 Series. They might be explained on the supposition of deriva- 

 tion from opposite sides of the Vale of Eden, the Lower Brockram 

 being supposed to come from the Carboniferous Limestone out- 

 crop towards Orton, while the Upper Brockram was derived 

 from the Pennine Range. This view has little to commend it. 

 If the Carboniferous Basement conglomerate was exposed to 

 denudation during the deposition of the Upper Brockram, then 

 the Carboniferous Limestone must have formed a bold and lofty 

 escarpment at the same time, and, that being granted, it is highly 

 improbable that it failed to yield the materials of the Lower 

 Brockram, which at Hungriggs is less than three miles from the 

 Outer Pennine Fault, which exposed a scarp of Carboniferous 

 Rocks in Permian times. Upon the alternative, and, as it 

 seems, preferable hypothesis, that the materials of the two 

 Brockrams were all derived from the Pennine Chain, an inter- 

 Permian movement of the faults which threw up the Cross Fell 

 Range and the well-known Inlier seems necessary. 



Professor Lapworth has pointed out that when an anticlinal 

 fold is exposed to denudation the derivative beds will consist 

 of the same material as those of the anticline, but in reverse 

 order. The uppermost beds of the anticline will yield the 

 pebbles in the lowest of the derivative beds, while the core 

 of the anticline will be represented only in the highest of the 

 'derivative beds. This principle may be illustrated by the 

 Tertiary Beds of the south-east of England : the Lower Eocene 

 Conglomerates contain only flint pebbles from the Chalk, while 

 the high-level gravels which rest on the Bagshot series contain, 

 besides flints, many pebbles derived from the Lower Greensand. 



1902 October i. 



