416 



LOWER SILURIAN ROCKS OF THE MALVERNS. 



Midsummer Hill, where it is pierced by the syenite. On the western flank of Ragged Stone Hill, 

 where the high road from Worcester descends from the Malvern ridge, are quarries of pale-green, 

 fine-grained, slightly micaceous, earthy sandstone, as represented in this wood-cut. 



86. 



The mass of the rock is apparently void of regular laminae of deposit, but it passes upwards into 

 hard, flaglike, and highly micaceous layers. Although this sandstone is traversed by numerous 

 vertical and oblique rents, it is on the whole a fine free-stone, capable of being worked into any 

 form, and might be termed green sand with as much propriety as any rock in the geological series. 

 Judging from the structure of this sandstone and its proximity to a great fissure of eruption, I am 

 disposed to think it may have been formed during submarine volcanic eruption, and is, therefore, 

 similar in some measure to certain rocks on the sides of Caer Caradoc and other parts of Shropshire. 



On the whole, however, the predominant colours of the sandstones and grits are dingy-red or 

 brownish-purple, as in Shropshire. With the exception of the upper band, calcareous matter does 

 not seem to be so prevalent as on the western side of Herefordshire. 



On the west flank of the Malverns, the south-westerly strike of the strata, and the southerly 

 direction of the Malvern chain, necessarily produce an expansion of the lower formation, caused by 

 the divergence of the ridges which are respectively composed of syenite and upper Silurian deposits, 

 (See Map.) At this point, therefore, strata still lower than the grits and sandstones above described, 

 are brought to day in highly inclined and contorted positions, west of Key's End Hill, and at the 

 White-leaved Oak. They consist of very thinly laminated, perishable, bluish, slaty shale, with 

 bands of hard, compact, flaglike sandstones. Though these black shales and flags may represent 

 the Llandeilo formation, I have not detected organic remains to complete the analogy ; it would 

 be therefore premature to assert that this member has any distinct existence in the east of Hereford- 

 shire 1 . Though it is highly probable that we are here presented with a miniature development of 

 the whole series, and that the black schist and shale represents the lower rotch of Caermarthen shire 

 and Pembrokeshire, which there constitutes the beds of passage into the Cambrian System. (See 

 p. 357=) The full succession of the Silurian series, between the syenite of the Malverns and the 

 Old Red Sandstone, is beautifully exposed in a transverse section from Midsummer Hill to Led- 

 bury. (PL 36, f. 8.) 



Such is a brief outline of the structure and disposition of the Silurian rocks on the 

 western flanks of the Malverns, and the range thence to the Abberley Hills. Further 

 analogies may be worked out by those interested in these tracts, by a reference to the 

 preceding chapters, in which the full types of the same formations are described. To 

 comprehend the nature and amount of the dislocations and undulations to which these 

 masses have been subjected, the reader, after examining and comparing the various 



1 Some of the associated shale is so black, and decomposes so readily, as to produce a surface very much re- 

 sembling that of certain coal-fields. Indeed, trials for coal were made in this spot, and hence the name of Coal 

 Hill has now become fixed, (see Ordnance Map,) as if to deter all future speculators from such absurd attempts. 



