BY HUGH MILLEE. 297 



first advanced by Scrope in 1825, as a probable explanation of 

 the escarpments ranged round the central area of the AVeald in 

 South-East England ; and he proposed to call the resulting hol- 

 lows 'Walleys of elevation and subsidence," or "anticlinal 

 A^alleys."* Abandoned by Scrope, for at least the Wealden Es- 

 carpments, in a later edition of his '' Yolcanoes," Mr. Kinahan 

 in his recent book, "Eaults, Eractures, and Eissures," has again 

 brought it forth, and striven to apply it to them.f The Northum- 

 brian escarpments also, Mr. Kinahan would perhaps say, have 

 been protruded or withdrawn one upon another. It might even 

 suggest itself that the Whinsill, the mid-rib of the escarpments, 

 may have been an agent in effecting protrusion. The latter idea 

 at least is not for a moment tenable. This intrusive Easalt has 

 been thrust along the planes of strata evidently under the pres- 

 sure of great overlying masses, possibly never even reaching the 

 surface at all. As for the other, it will be found that the shales, 

 along the line of which, and, as it were, lubricated by which, 

 the sliding of bed on bed is supposed to have taken place, give, 

 wherever visible, no signs of the crushing disturbance that must 

 needs accompany the process. The smallest faults effect recog- 

 nisable changes in these laminated shales, multiplying their joints 

 or mashing them up into clays. This theory, which runs counter 

 to the whole spirit of modern geology, is also for direct reasons 

 quite untenable. 



3. Marine Theory. — So far back at least as the controversies of 

 Hutton with De Luc it has been asserted that channels may have 

 been left upon the earth by the sea. In his "Eivers of York- 

 shire," Phillips explained both the dales and the scarped features 

 of that county mainly upon this theory.]; In his later days, 

 though occasionally appearing almost overwhelmed by proofs of 

 present atmospheric action upon ''bases of unequally resisting 

 materials," he still seems to have held to his early views. || 

 Without giving any opinion upon the part the sea may have taken 

 in the excavation of valleys, whether at a time when currents 



* Foster and Topley. Quart. Jour. Geol. Soc, Vol. XXI 11.. p. 460. t p. '2(tl. 

 X Rivers, Mountiiins, nnd Sea Coasts of Vorksliiro, 1855, p. !•. 

 I! Ocolo<ry of Oxford and the Tluunos N'nllcy. 1S71, i>. 4SG 



