212 



WENLOCK LIMESTONE, (LOWER PART OR SHALE.) 



Similar massive concretions, and of equal value, are exposed in the contiguous 

 quarries of Bradeley ; and the whole of the calcareous rocks around Gleedon also con- 

 sist of crystalline concretions, of greater or lesser size, subordinate to thin argillo-cal- 

 careous beds. Some of the argillaceous matter is here of peculiar tenacity and of a 

 white colour resembling pipeclay. Another remarkable ball-stone (not yet consumed 

 by the lime-burners,) lies to the south-west of Wenlock, and is called "Ippikin's rock." 

 It constitutes a boss, the summit of which is about four or five hundred feet above the 

 valley occupied by the Wenlock shale. The rock itself has a vertical face of fifty or 

 sixty feet, which is partially fissured, and presents an entrance into a small cavern 1 . 

 It is a mass of crystalline limestone, the edge of which, as in the examples previously 

 mentioned, is in abrupt contact with the ends of the surrounding strata. 



The central and massive portion of the Wenlock formation, thins out rapidly to the 

 south-west of Easthope, and although limestone is worked at various places along the 

 crest of the south- western extremity of the edge, the largest nodules only are selected for 

 use. Between the gorges of the Onny and the Teme, the line of this calcareous zone 

 is marked by a few quarries, containing the small concretions only, the strata being 

 much denuded in the low grounds of the valley extending by Clungunford to Leint- 

 wardine, but in the neighbourhood of the latter place the limestone re-appears through 

 the surrounding shale near Clifton Ford Bridge. From this point it ranges distinctly 

 around the interior of the Ludlow promontory, forming an inner and lower ridge, or 

 rather a succession of bosses, the beds of which dip beneath the overlying escarpment. 

 (PL 31. fig. 5.) It appears in like positions at the base of the escarpment of the Ludlow 

 formation at various places near Aymestry, and is fully developed between Wigmore 

 and Dickendale, and again on the banks of the Lugg near Kinsham. 



In these situations it is made up of concretions, varying in diameter from two inches 

 to two feet, which are abundantly charged with fossils, particularly corals. The nodules 

 differ much in lithological structure, the smaller consisting solely of dull, grey, argilla- 

 ceous limestone, whilst many of the larger are made up of white crystallized carbonate 

 of lime, 



Wenlock Shale. — Synonyms "Dudley Shale." (/. of wood-cut, p. 196.) 



The lower part of the Wenlock formation, as already stated, consists of a great de- 

 velopment of dull, argillaceous shale, rarely if ever micaceous, and contains here 

 and there, a few concretions of very impure, argillaceous, limestone. In colour, aspect, 

 and want of cohesion these strata are nearly identical with those of the lower Ludlow 

 rock, and they constitute the base of the Upper Silurian or " mudstone " rocks 2 . The 



1 This cavern, tradition says, was formerly inhabited by a person of the name of Ippikin. It has been re- 

 cently examined at my request by my zealous young friend Mr. R. W. Evans, to ascertain if it contain the 

 remains of cavern animals. The result will be communicated in the concluding chapters. 



2 The miners of the coal-field of Coal Brook Dale apply the name of "Die Earth" generally, to any beds of 



