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



and gritty beds. If reference will be made to the Horizontal 

 Section through the Skiddaw Slate Series, No. 2, page 54, the course 

 of which is marked in the accompanying Sketch-map, the sequence 

 and lie of these subdivisions will be clearly seen. The central range 

 of high mountains along this section shows the lower sandy series 

 in their fullest development, the physical equivalents — as it would 

 appear from above — of the Lingula Flags ; and the black slates 

 beneath the grit at either end of the section (shaded more darkly) — 

 physical equivalents of Tremadocs — come in as a faulted synclinal 

 in the valley between Whiteside and Grasmoor, the latter mountain 

 presenting a very exceptional example of a summit formed by an 

 anticline. 1 



Eeferring to Horizontal Section No. 1, page 54, it will be seen that 

 the grit of Great Cockup dips southwards under the mass of Skiddaw 

 (see also Map), and only reappears in an anticlinal fold on the south 

 side of that mountain. Thus, the area of Skiddaw and surrounding 

 mountains is mostly made up of the slates above the grit, the phy- 

 sical equivalents — and in this case the palseontological equivalents 

 also — of the Welsh Arenigs or Lower Llandeilo. In a set of rocks 

 so highly contorted as are those of the Skiddaw Slates, taken as a 

 whole, it is often impossible to detect and trace the faults ; but if my 

 reading of the district be at all correct, there must, I think, be some 

 large N. and S. fault or series of faults separating the tract of 

 Skiddaw, etc., from that W. and S.W. of Derwentwater and 

 Bassenthwaite Lake. This I have indicated in the Sketch-Map. 

 That there are many such N. and S. faults of great size is proved 

 by the frequent shiftings of the grit west of Great Cockup. In 

 Hor. Sect. No. 1, page 54, a large strike-fault throws down the Vol- 

 canic Series against beds far below the grit, and while this is very 

 generally the case for many miles west of Carrock Fell, yet is there 

 clear evidence at several points of the passage upwards into the 

 Volcanic Series of the higher beds of the slates above the grit. To 

 sum up the physical evidence : while fully acknowledging the fre- 

 quent inconstancy of physical characters, there does seem to be in 

 this case of Cumbria and Cambria, some 60 to 80 miles distant from 

 one another, a striking sequence of similar deposits, such, indeed, as 

 to lead me to infei", so far as physical evidence can do so, that in 

 Cumbria we have the following groups represented which are more 

 or less equivalent to those of Wales. 



Arenig Slates — True Skiddaw Slates. 



Arenig Grit. 



Tremadoc Slates. 



Lingula Flags. 



It is impossible everywhere to define the limits of these groups, so 



contorted and faulted is the District; but that they exist as generally 



definable subdivisions I have myself no doubt. It would seem — 



as already called attention to in the Survey Memoir — that the lowest 



1 This may be well seen looking up on to Grasmoor End from Crummock Water. 

 In Horizontal Section No. 2, the upper black slate should have been represented as 

 conformable to the underlying grit of Elya Hill. 



