560 Geological Society : Mr. D. Sharpe on the 



above Shap Wells to its junction with the Lune at Tebay, intersects 

 a deposit of old red sandstone, and the same deposit extends for 

 some distance eastward up the valley of the Lune. It consists of 

 the usual triple division, but the passage beds into the Ludlow rocks 

 are entirely wanting, and the lower beds thin out in ascending the 

 valley from Tebay. It rests on the lowest portion of the Winder- 

 mere series. The dip is only 5° or 10° to the north-east. On the 

 opposite side of the ridge which separates the Lune from the Low- 

 ther, the old red again occurs in the valley of the latter river, the 

 intervening ridge being occupied by masses of the doubtful brown 

 gravel. Throughout this district the lowest beds of the mountain or 

 scar limestone rest conformably on the old red sandstone. 



General Remarks ; or comparison of the Westmoreland strata with 

 the equivalents in other parts of the kingdom. — The triple division 

 of the Westmoreland old red sandstone, the author says, agrees re- 

 markably with that of Herefordshire, as already stated by Mr. J. 

 Phillips in his work on the Fossils of Devonshire ; the only differ- 

 ences being the disaggregated state of the conglomerates, and the 

 absence of the cornstones as well as of the Ichthyolites. The gradual 

 passage from the bottom of the old red sandstone into the Ludlow 

 rocks also coincides with the phenomena described in Herefordshire 

 by Mr. Murchison. The Ludlow rocks of Westmoreland will also 

 bear comparison with those of the border counties of England and 

 Wales ; but, owing to the absence of the Aymestry limestone, it is 

 not possible, the author states, to fix the exact relative position of 

 the former with respect to the latter, but he says that they exactly 

 agree with the upper division of the upper Silurian rocks of Den- 

 bighshire, as described by the late Mr. Bowman*. With respect 

 to the Windermere series, the author likewise hesitates to place it 

 on an exact parallel with any of the subdivisions of the Silurian as 

 described in Mr. Murchison's work, but he states that it precisely 

 agrees in part with lower divisions of the Denbighshire upper Silu- 

 rian rocks, both in general characters and the details of the com- 

 ponent strata. The Coniston limestone Mr. Sharpe, as already 

 stated, prefers to consider as a lower Silurian deposit, than as the 

 equivalent of any one of the members of that series of rocks. 



The author then enters upon the inquiry of the principal epochs 

 of disturbance and elevation of the Westmoreland rocks ; and he 

 shows, 1st, that the earliest period of disturbance was connected 

 with the outburst of the Shap granite ; inferring, from the conform- 

 ity of the Windermere rocks with the Coniston limestone, that all 

 these series were deposited before the outbreak of the granite ; 2nd, 

 that the old red sandstone resting horizontally on the elevated rocks 

 of Shap Fell, proves that this formation was accumulated after the 

 disturbance consequent upon the protrusion of the granite; 3rd, 

 that all the faults which affect the old red sandstone, or any newer 

 formation, are more modern than the outburst of the granite. 

 Although difficulties attend the fixing of the age of the Ludlow rocks 

 relative to the outburst of the granite, on account of the complicated 

 * Athenreum, No. 719, Aug. 7, 1841. 



