Joseph Lucas — The Permian Beds. S39 



gives the name of Eed Scar to- several scars on Great Wliernside-. 

 I am told that the occasional outbreak of a ferruginous spring from 

 coal-workings will kill the river fish for miles ; so that if nothing 

 but iron had been precipitated in the Permian Sea, the effect on the 

 fauna would have been the same. Sulphureous springs also break 

 out from the Millstone-grit, one at Aldfield may be perceived for a 

 quarter of a mile, where there is a draught along the valley in which 

 it lies, and the Carboniferous Limestone- contains magnesia. 



As regards the lime, it is confessedly not derived from organisms, 

 that lived in the Permian Sea, and the limestone being over a very 

 large area uniformly thinly and evenly bedded seems to have been 

 deposited tranquilly in still waters. Little rivers flowing from Car- 

 boniferous hills, cutting through Millstone-grit to the Yoredale lime- 

 stones, would bring with them supplies of lime, magnesia, and iron, 

 in quantities practically without limit. I cannot see that anything 

 more is required to suit the facts of the case. From these sources and 

 the Coal-measures would then be derived the principal part of the 

 sediments deposited in the Pfermian basin. Not knowing how far 

 the question is considered to be settled, I do not take it for granted 

 that the Pennine anticlinal ridge was formed before the deposition 

 of the Permian beds, but I think the evidence is very strongly in 

 favour of such a probability. For through the Millstone-grit rocks 

 from Wharfedale northwards, run many anticlinals approximately 

 E. and W., and many of these pass under the undisturbed Mag- 

 nesian Limestone ; several large faults do the same ; the base of the 

 limestone is bounded by a wonderfully regular line, and is not sinuou& 

 or broken up into outliers opposite the high ground north of Eipon. 

 Not a single outlier occurs anywhere on the chain, and not one- 

 creeps even a little distance up the slope. From Leeds north- 

 wards, as far as Bedale, the pale yellow limestone rests on bare 

 Millstone-grit, with in one or two places the most trivial excep- 

 tions. All these facts seem to point to- the same conclusion, viz. : — 

 that a limit of the basin is reached, and approximately represented 

 by the present base of the Magnesian Limestone, at least for that 

 distance. For the absence of sediments below the lowest limestone 

 during that space seems to point to an overlap of the limestone over 

 sediments previously deposited, whereby the limestone was brought 

 to rest against the bare sides of the basin. It now dips east about 

 6°, some 2° or 3° of which may have been original deposition. 



Two other facts seem also to favour the idea that the Pennine anti- 

 clinal was formed before the deposition of the Permian beds ; firstly, 

 that fragments of Carboniferous Limestone do occur ^ on the west side 

 in the basin below the Magnesian Limestone, and secondly, that on 

 the east side in Yorkshire and Durham they do not. For on the 

 steep West side of the anticlinal, the Carboniferous Limestone must 

 have been exposed to allow those fragments ta appear ; and on the 

 East, for some distance at least, it was probably covered with a thick 

 series of grits and shales. I am aware that the concretionary 

 nodules in Durham may be formed round pebbles of Carboniferous 



^ Eamsay. Pretriassic Ked Eocks. Proc. Geol. Soc, vol. xxvii., p. 246. 



