312 Mr. N. Wood on the Geology of Northumberland, <§-c. 



The Fern Islands, which lie nearly east from this place, are entirely 

 composed of Basalt ; and as the Basaltic rocks at Bamburgh dip in that 

 direction, the Basalt of these islands is probably a continuation of the 

 same bed. The Whin of Bamburgh extends north into the bay of Budle, 

 where it has been extensively quarried. It also stretches westward to 

 Belford, &c. which will be noticed hereafter. From Budle Bay, to be- 

 yond Holy Island, a flat sandy beach occurs ; but the Basalt again 

 appears at Holy Island, which is probably the termination to the north, 

 the rise in the beds finally throwing it out at that locality. 



Passing Holy Island, we again meet with the Limestones which un- 

 derlie the Basalt. The first of these is a black Limestone, dipping 

 N. W. at an angle of 35° ; upon this lie some thick beds of Red Gritty 

 Sandstone, which gradually flatten northward, apparently shewing the 

 contrary dip of the Limestone to have been occasioned by a Dyke. 



The. beds then take a determined and regular rise to the north, pre- 

 senting a series of beds of Limestone, Sandstone, and Shale rising out 

 from underneath each other, and terminated by thick beds of Red 

 Sandstone rocks stretching across the mouth of the Tweed. 



The Section, Plate XXVI. though exhibiting a pretty accurate repre- 

 sentation, of the order of superposition of these rocks, is not quite per- 

 spectively correct. The beds, which about half a mile south of Spital 

 rise N.W., the line of direction being N.E., when opposite Major John- 

 son's house, gradually change their direction, until the line of bearing 

 is north, and the dip almost due east into the sea. The lower beds of 

 Red Sandstone, underlying the Limestone beds, therefore stretch across 

 the estuary, and are found on the north side of Berwick Pier. 



Tracing the series, from a thick bed of black Limestone, shewn in 

 the Section ; we find that rock overlying first a series of beds of Lime- 

 stone and Grit rocks, then a very thick bed of Red Sandstone, under 

 which lies a bed of Coal ; below this are thick beds of Shivery Sand- 

 stone and Plate, overlying a bed of blue Limestone 8 to 10 feet thick, 

 followed by a thick bed of compact Red Sandstone, at least 40 feet 

 thick, resting on alternating beds of Sandstone, Shale, and thin beds of 

 Coal ; below these is a bed of workable Coal, reposing upon a series 



