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valley of Wigmore, though not so regular and perfect as that of Woolhope now 

 so well known, deserves a more extensive examination than we were enabled 

 to give it. Its physical features are very striking. The escarpment and slopes 

 from the fault at the Bow bridge over the Teme, along Bringewood Chase to 

 Mary Knoll, Whitcliffe and Ludlow ; thence by Ludford to Richard's Castle, 

 the High Vinnals and Gatley, and the exterior diverging escarpment from Orleton 

 Common to Croft Ambrey and Aymestry, with the numerous transverse valleys 

 by which they are cut into and through, especially Mary Knoll Dingle, the Hay 

 Park, Croft Castle Dingle and Aymestry Valley, afford most instructive sections, 

 in many places abounding with fossils. The broken-up strata of the lower escarp- 

 ment, forming the picturesque knolls from Aston Common to Elton and Leinthall 

 Starkes, cannot fail to attract attention ; whilst the road from the finger-post 

 at Elton to Richards* Castle and Orleton presents excellent sections of the 

 Wenlock Shales and limestone, the lower Ludlow beds, Aymestry limestone, and 

 upper Ludlow with the Downton beds — in fact, the greater part of the upper 

 SUurian — into the Old Red Sandstone. The valley of Wigmore abounds with the 

 detritus of the surrounding rocks, which was also found swept out over portions 

 of the Old Red Sandstone between Ludlow and Leominster. The absence of gravel 

 within the valley of Woolhope has been remarked by Sir Roderick Murchison. 



These visits having thus made us acquainted with good types of the upper 

 Silurian beds in regular succession, in their most classical locaUties, the Kington 

 meeting was designed, for the examination of the Nash-scar limestone, near Pres- 

 teign, and the igneous outburst of Radnor and Stanner. The position of the 

 Nash-scar limestone, originally regarded by Sir Roderick Murchison as the 

 equivalent to Wenlock (— Dudley and Ledbury) limestone, has given rise to some 

 controversy. Professor Sedgwick, in his first visit to the district, suggested that 

 it was of an earUer date, the equivalent of the lower band, appearing in the centre 

 of the Woolhope valley, and which Sir Roderick had classed as Caradoc or lower 

 Silurian. The Geological Staff of the Ordnance Survey adopted the Professor's 

 views. The question has been carefully investigated by J. E. Davis, Esq., of the 

 Middle Temple, our honorary associate, and happily on this occasion we had the 

 benefit of his presence, amd under his direction examined the most interesting 

 points of the district. A paper on the age and position of this Umestone was read 

 by him before the Geological Society of London, in May, 1850, which will 

 be found in their journal of Nov. of that year, in which the question, confessedly 

 one of difl&culty, is very ably discussed. Since the question was mooted, more 

 extended observations have removed the Woolhope limestone from the Caradoc 

 into the Wenlock series ; so that the question is now, to which of these bands 

 —viz., the upper or lower Wenlock limestones — is the Nash-scar limestone to be 

 referred. The evidence collected by Mr. Davis, more especially, of the organic 

 remains (for mineral structure quite fails in this case), inclines me to the position 

 originally assigned to it, by Sir Roderick. The Nash-scar affords a fine example 

 of metamorphic or altered limestone, occasioned by contact with igneous matter, 

 injected against or between the strata, maintaining a high temperature, under 

 great pressure, for a considerable time, producing a complete change of mineral 

 structure, destructive of stratification, and in some parts of almost all traces of 



