UPPER SILURIAN ROCKS— LUDLOW FORMATION. 



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termination. These masses are thrown up from north to south, the strata dipping to 

 the east and west, the latter inclination being most prevalent. 



Of these masses, the principal, or that of Sedgeley, resembles in part the form of an inverted ship, 

 the prow of which is exposed in a circling line of quarries, midway between Sedgeley and Wolver- 

 hampton, the stern towards Upper Gornals ; the western side of this promontory is the most in- 

 structive, and the rocks, rising at a sharp angle, are traceable from opposite Sedgeley Park school to 

 beyond the Catholic Chapel, a distance of nearly two miles. The higher part or round keel, sepa- 

 rated from the western side by undulations, rises to the Beacon hill, 650 feet above the sea, whence 

 to the eastern side the ground sinks gradually, without affording any clear exhibition of the strata. 

 This promontory, therefore, emerges suddenly, like an island from beneath the surrounding coal 

 measures, and thus resembles other Silurian rocks to be described. 



In the numerous quarries, both along the western flank and at the northern and southern ex- 

 tremities, as well as near the village, the inclination of the strata varies greatly. At the northern 

 or lower end, the arrangement of the elevated beds is beautifully symmetrical, and may be strictly 

 compared to the bow of an inverted boat or ship, the beds plunging N.N.E., N., N.N.W. and W., 

 at angles from 65° to 40°. In ascending to the higher grounds, the strata are much contorted, 

 and the beds dip 25° W.S.W., whilst at the south-western extremity of the range they dip to 

 the south-west at 25° and 10°, and then again veer round to the north-east. On the southern face, 

 near the Catholic Chapel, the rock is inclined only 10°, and at Shaver's End is in abrupt con- 

 tact with the unproductive shale and coal grits of Gornals. The arrangement on the eastern side 

 is explained at Turl's Hill, a small offset from the main hill of Sedgeley, in which the strata dip to 

 the west at 15°, being thrown off from the adjacent ridge of Wenlock limestone. This disposition 

 is explained (PI. 37- f. 4.), and in it we see how the Aymestry limestone is brought to the surface 

 by undulations. 



Of the Upper Ludlow rocks there are only thin exhibitions in the open works, which is what 

 might be expected, since the limestone alone being the object of the quarriers, it is only extracted 

 where there is little overlying matter to remove. Enough, however, has been cut through at 

 various points to show the nature of the rock, particularly on the western side of the hill, where 

 30 to 40 feet of argillaceous thin-bedded sandstone are exposed, containing the Leptcena lata, the 

 Serjmloides longissima, and other well-known fossils. From the dip of the Aymestry limestone at 

 Turl's Hill, where it occupies the cap of a low ridge, there is little doubt that the whole of the higher 

 part of the Beacon Hill is composed of the Ludlow rock. In these localities the beds lie tolerably 

 level, as between Turl's Hill and Sedgeley, and probably also near the summit of the Beacon Hill. 

 There can therefore be no doubt, that the limestone may be reached by excavations of moderate 

 depth over a very considerable extent, an inference of some practical importance, and which renders 

 this hill of greater value than its owners may be aware of. (See PI. 37- f. 4.) 



Aymestry or Sedgeley Limestone (Limestone of the Ludlow Formation). 



In passing downwards, the Upper Ludlow rock, as in Shropshire, contains small cal- 

 careous concretions. These nodular beds of impure limestone constitute the cap of the 

 Sedgeley limestone for a thickness of 30 to 40 feet. They are underlaid by the best 

 limestone, which varies from 15 to 21 feet in thickness, and presents regular beds of the 



