426 J. Prestwich, Esq., on the 



In the road leading from the Hatch to the Wrekin^ and in some other places, 

 the superposition of this limestone on beds of trap, with their rise against the 

 igneous axis of the Steeraways, is well exhibited. Prom Steeraways to Lilies- 

 hall the limestone is not exposed ; but at the latter place, it forms a narrow 

 band about l^ mile in length, overlying the trap and Silurian rocks, and rising 

 from beneath the coal-measures. It abuts against new red sandstone on the 

 west. The dip varies from N.E. to E.and is at different angles. 



The north end of this wedge of limestone exhibits an apparently anticlinal 

 line in the prolongation of the major axis of Lilleshall Hill, w hence it might be 

 supposed, that the limestone wraps all round that hill, but there is nothing 

 further to support this hypothesis. The anticlinal dip takes place within a 

 few yards of the Lilleshall fault, ranging parallel to it, and might therefore 

 have been produced by the lateral pressure of the new red sandstone. The 

 limestone at its outcrop near Lilleshall, is capped by a few yards of fissile 

 sandstone, belonging to the coal-measures, which from the northward dip of 

 the strata, rapidly acquire a greater importance, though not sufficiently to 

 bring in the productive measures. This zone of limestone gradually decreases 

 in width by the convergence of the Lilleshall and great east faults, and near 

 Church Ashton it disappears in consequence of these faults meeting*. (See 

 Map and Sections.) 



Between Lilleshall and the pool at the bottom of the Hadiey inclined plane, 

 no sinkings have been made, which could point out exactly its course below 

 the coal-measures : in digging "the pool," however, the limestone is said to 

 have been met with, striking parallel to the fault. It was reached also in a 

 pit sunk by Mr. Hombersley about half a mile south of Watling Street, at a 

 depth of 80 yards, and in a nearly horizontal position. At Steeraways the 

 limestone has been traced only a few yards below the coal measures ; but its 

 range under them has been lately confirmed, by its having been noticed rising 

 to the surface at the Horsehays, in the centre of the coal-field. Owing to 

 its rapid dip to the N.E. and small development, it has not been worked, and 

 its further prolongation therefore is not positively known. Nevertheless 

 there is no doubt that the carboniferous limestone immediately underlies the 

 coal-measures from Little Wenlock to Lilleshall. (See PI. XXXVI., Sections 

 5 to 7, 13 and 14.) 



At Little Wenlock and Steeraways the upper beds of the limestone are very 

 thin, argillaceous, and of a bluish gray colour. As the strata descend they 

 become purer, but still contain much alumina and silica, which cause the lime, 

 made from this rock, to set well under water. It is quarried for several 

 iron furnaces. At the above places and at Lilleshall, the lime rock is subor- 

 * Its depth at this point is 150 yards. 



