Mr. N. Wood on the Geology of Northumberland, S^c. 329 



throughout its course, especially at Croglin, where, although it clearly 

 occurs as a bed, with Limestone resting on it, yet in some places it has 

 the appearance of having been injected between the beds, displacing, 

 in several instances, the Limestone and Shale into detached masses. 

 Along the range of hills, between Glenwhelt and ChoUerford, its cha- 

 racter as a bed may be seen ; east of the North Tyne also, and particu- 

 larly at Bavington, where in the Lead Mine it has been sunk through. 

 It does not, however, occur in all this range as a single bed or stratum, 

 but in several places, appears divided into two or three, with thin beds 

 of Limestone or Sandstone intervening, as at Bavington, &c., and the 

 coast section will shew its effects upon the strata at Howick. The great 

 correspondence of the range of basset of the Basalt, with that of the 

 upper beds of Limestone and Coal, shews that it keeps nearly the same 

 position in the series ; and it is somewhat remarkable, that at the two 

 extremities of the range, at Croglin and Dunstanburgh, the Basalt 

 reposes upon a bed of black Limestone of nearly the same charac- 

 ter. 



We come, now, to the great beds of Limestone, Shale, and Sand- 

 stone, which underlie the preceding strata : as previously noticed at 

 Croglin, some of the beds of Limestone, below the Basalt, crop out on 

 the face of the escarpment before we reach the plain of Red Sandstone ; 

 but here the Red Sandstone and debris, at the foot of the hills, lie 

 against and cover a considerable portion of their base, so that the lower 

 beds are not exposed. This is the case along the whole face of these 

 hills to near Talkin. Here, as before observed, a change takes place 

 in the direction of the beds, the full rise, which at Croglin is nearly 

 west, now verges round to the north west. The eastern limit of the 

 plain of the Red Sandstone, or western edge of the Mountain Lime- 

 stone, stretches away north into Scotland, partly in the line of the rise 

 of the strata ; and as the plain of Sandstone is comparatively level, in 

 following the western edge of the Limestone, we successively get 

 lower down in the series in proceeding northward, and at the junction 

 of the Liddle and Esk rivulets, we arrive at nearly the bottom of the 

 Limestone beds. The western face of these beds now covers a considerable 



