Rev. J. Clifton Ward — Geology of the Lake District. 53 



parts, of at least 12,000 feet, and the highest beds known (the fine, 

 altered, almost flint-like ash of Great End, Esk Pike, and Allen 

 Crags) are unsucceeded by any conformable series of sedimentary 

 rocks ; hence we know not how much of the products of the old 

 volcano has been lost, and, for aught we know to the contrary, an 

 Etna in size may have once stood where now are the resting-places 

 of quiet lakes. In this connexion it is interesting to remember how 

 little of our miniature mountain dish'ict would be uncovered, could 

 we transplant Etna bodily with its surrounding volcanic ejecta to the 

 site of the present Lake District. 



Note. — In my previous papers, read before the Geological Society, 

 and in the Survey Memoir, I have given my reasons for believing 

 that the several granitic areas of the district were not connected 

 with the volcanic deposits as cause with effect. It may well be 

 that one or more large centres of eruption now lie hid beneath 

 the unconformable overlap of Upper Silurian and Carboniferous 

 rocks. 



Bb. — Unrepresented Period. 



Between the periods indicated by B and C, there comes an 

 interval of unknown duration which we may represent by Bb. 

 This was a time of which we have no records left, but the duration 

 of which is made clearly evident by records abstracted. It is as if 

 the latter part of volume B was torn away, and hence we infer 

 a denuding action subsequent to its completion. 



Our Cumbrian Etna had ceased its activity, and, as so frequently 

 happens, a subsidence of the volcanic region ensued, accompanied 

 doubtless by much waste of the volcanic material through the agency 

 of atmospheric denudation. Subsidence, however, continued until 

 the old volcano came within the planing power of marine coast- 

 action, and at last there was probably but little of the old terrestrial 

 volcano left above the level of the sea. 



Eor Cumbria, this is undoubtedly the point at which one would 

 draw the line between Lower and Upper Silurian. Here is a great 

 physical break, and the deposits accumulated above the Volcanic 

 Series are markedly transgressive in their strike to those of that 

 series, though, undoubtedly, for a certain distance east of Coniston, 

 the strikes do more or less correspond. West of Coniston, however, 

 nothing can be clearer than the successive curving round in strike 

 of the divisions of the Volcanic Series and their abutment at right 

 angles against the outcrop of the Coniston Limestone and Upper 

 Silurians. 



The period unrepresented by deposition, but made clear through 

 denudation, was brought to a close by the formation on the bed of 

 that Mid-Silurian sea of a deposit of limestone (the Coniston), rich 

 in the remains of marine life. But here we meet with evidence of 

 a slight return of volcanic conditions, and mingling with the 

 calcareous deposit a bed or beds of lava were poured out. This 

 time, however, the lava belongs decidedly to the more highly silicated 

 group, and the felstone now associated with the Coniston Limestone 



