472 



LOWER COAL AND IRONSTONE MEASURES. 



and is extensively quarried, exhibiting thick bedded strata, largely used for building and 

 containing impressions of stems of plants and occasional thin partings of coal smut. 



Lower Coal and Ironstone Measures. 



It has been stated, that the lower coal and ironstone measures crop out from under 

 the 10 yard coal and extend into the great Wolverhampton field. In their spread to 

 the north, however, these lower strata assume very different lithological and mineral 

 characters, from those where they underlie the thick coal at Dudley, Corngreaves, and 

 in the portion of the field south of Bilston and Wednesbury. In most of the works, 

 which have hitherto been established, in the region of the 10 yard coal (near Dudley 

 or south of it), three courses only of workable iron ore have been ascertained ; whilst 

 in the Wolverhampton district six valuable bands are wrought 1 . Some persons may 

 think that this apparent dissimilarity between the productions of the northern and 

 southern fields does not really exist, but is merely due to the want of sufficiently deep 

 works. This opinion ought to have some weight in arguing upon the unproved beds 

 which may exist beneath the strata covering the coal near Hales Owen. It cannot, how- 

 ever, apply to the great central body of the coal-field ; for there the very lowest measures 

 appear repeatedly at the surface, in consequence of the protrusion of the Silurian and 

 trap rocks, and hence the practical miner has long been acquainted with the very bottom 

 of the field. Such outcrops occur around Netherton Hill — along the edges of the hills 

 of Dudley and Sedgley, particularly on the east side of the road from Dudley to Sedgley 

 — at Wednesbury ; and in none of these is there an indication of the rich ironstone 

 measures which occur in the Wolverhampton field. Hence the speculators in the 

 southern or 10 yard coal tract have always confined their sinkings to the beds with which 

 they were acquainted, and which seemed peculiar to their district 2 . 



At Stourbridge, where the lower measures occupy a nook, flanked on three sides by the Lower- 

 New Red Sandstone, and on the fourth rise from beneath the 10 yard coal \ though containing beds 

 of ironstone, they are chiefly worked on account of the saponaceous quality of the shale or fire clay 

 which is here so largely used for fire bricks. Three workable seams of coal have been wrought, 



1 By a band of iron ore, I mean one of those groups of concretions and imperfect beds in which two or more 

 courses of the ore are often separated from each other by shale or clunch. Thus, though we talk of six. bands 

 of iron ore near Wolverhampton, the reader will perceive, that these constitute in reality 14 courses. (See Table, 

 p. 479.) 



2 The general reader may be informed, that land in the productive ironstone tract of Wolverhampton, where 

 the lower coal only exists, is much more valuable than in the southern district, where both the thick and lower 

 coals are present. This anomalous assertion is reconciled by the fact, that the southern tract is so much less 

 rich in iron ore than the northern. It is seldom, indeed, that the mere existence of coal of any thickness and of 

 the very finest quality will of itself repay the speculators, and hence it is usual to transport the iron ore from 

 the Wolverhampton field to the pit mouths of the thick coal, south of Dudley, and there to smelt it, 



