1S2 Mr, WiTHAM on the Red Sandstones of Bevwickshire. 



from 15 to 18 feet. At Heaton-mill its breadth is near 24< feet, and at 

 Duddoe it widens out to 30 feet. It is seen farther east, and worked at 

 Millalloes or Morcelles. Neither Mr. Milnes nor I having had an oppor- 

 tunity of examining it in this spot, we were unable to make any remarks 

 upon it ; sufSce it to say, it is beUeved to extend to the neighbourhood 

 of Holy Island, and may probably be the same Basaltic Dyke seen 

 from the turnpike road leading from Belford to Berwick, a short distance 

 south of Haggerston. 



There is another Basaltic Dyke running in a parallel direction, a 

 short way further south. It is worked at Halidon-hill, and passes 

 Etal colliery, but Mr. Milnes has been unable to trace it any further. 



The rocks, therefore, after they cease to be disturbed by their proxi- 

 mity to the Cheviots, the whole way from Shoreswood and Morton, 

 (which I look upon as the higher portions of the Mountain Limestone 

 group,) rise at various angles towards the N.W., and appear to me to 

 demonstrate, that the Red Rocks, which accompany the Shales and 

 Limestones, from this quarter to the Lammer-muir hills, are all subor- 

 dinate beds of this Mountain Limestone group. 



The result, then, of these repeated journies over the ground and 

 repeated examinations, has been to produce a firm conviction on my 

 mind, of what seemed to me at first more than problematical ; namely, 

 that the Red Rocks in the neighbourhood of Berwick, and also those 

 seen upon the Tweed, the Black and White Adder, and in other locali- 

 ties of this district, are not the new Red Sandstone, but subordinate 

 members of the Mountain Limestone series. 



In a paper written by me, and published in the Annals of Philosophy, 

 July last, on the Vegetable Fossils found at Lennel-braes, near Cold- 

 stream, I made use of the term " Coal Formation," there being beds of 

 this combustible matter in this series. By some this is looked upon as 

 correct, still as these rocks all lie below the Coal-field proper, I think 

 it more correct to class them as a Mountain Limestone group. South 

 of Berwick in this formation, several good beds of Coal are worked. 

 How far the subordinate members may prove fruitful in this useful 

 commodity must at present remain matter of great uncertainty. 



