On the Upper Old Red Sandstone and Upper Devonian Rocks

I was engaged for three summer months in 1854, and again for a short tune last year, in examining carefully the lower beds of the Mountain Limestone and the uppermost beds of the Old Red Sandstone, with a view to establish, if possible, the correlation between the Upper Old Red and the corresponding portion of the Devonian series —a relation which has been called in question by good observers. The memoir of Sedgwick and Murchison was, indeed, a full statement of the identification of the Old Bed Sandstone, as a maas, with the Devonian; a comparison first suggested by Lonsdale from a consideration of the fossil evidence, and ably supported by Godwin-Austen from his Rhenish explorations, though afterwards called in question by him. The identification is repeated in the later edition of ‘Siluria.’ Yet, over the North-European districts, there is a singular deficiency of proof of the superposition of the Devonian to the Tipper Silurian rocks, and more especially of the gradual passage, at any one point, of the Old Red Sandstone into rocks of the Devonian type.