126 Notes on the Geology of Corhridge. By G. A. Lebour. 



entire mass. Another point to be noticed is this, viz. : that the 

 three intercalated limestones occur towards the upper part of this 

 group of beds, nearer to the Felltop than to the Little Limestone, 

 there being as much as 1250 feet (out of the 1450) of sandstones 

 and grits with scarcely any shale between the lowest of the 

 intercalated limestones, No 4, and the Little Limestone. These 

 sandstones and grits occupy the whole of the sloping ground 

 north of Corbridge between the town and Stagshaw Bank, and 

 are especially well seen at Inghoe, a little village standing 

 on the summit of a bold escarpment about four miles north of 

 the Eoman "Wall, and very well seen from thence. To these 

 grits, which are often very coarse, the name of Inghoe Grits has 

 been given.* 



The Little Limestone, a bed well-known but not very often 

 exposed in Northumberland, has been largely quarried at Halton 

 Shields. The quarries here are interesting as they are opened 

 in an abnormal thickening of the limestone which is here jam- 

 med between two nearly parallel N.W. and S.E. faults. As a 

 result of this "squeeze" the stone is much broken up, in places, 

 into a regular breccia, and the interstices between the fragments 

 are filled with Carbonate of Lime by which the whole has been 

 re-cemented. Some very fine specimens of Calcite in large nail- 

 head crystals are frequently found in nests, lining cavities in this 

 crushed Limestone. 



A small colliery is worked at Halton Shields close to the 

 quarry just mentioned, and another, scarcely larger, at Stagshaw 

 Bank between the Military road and Grottington. These are 

 established to work the coal known as the Little Limestone coal, 

 a seam which occurs beneath that Limestone and, under various 

 names, has been worked near its outcrop across the whole 

 county. It is the same coal as that at Acomb, Blenkinsopp, 

 Clarewood, and BoghaU. 



Other thin and seldom worked seams occur near to and below 

 each of the three intercalated Limestones. 



At Bewclay on the Watling Street the fine and bold range of 

 the Great Limestone is a prominent feature in the landscape, the 

 outcrop of the stone, owing to the denudation off its dip -slope 

 of the overlying thick shale, beyond of unusual breadth. Very 

 good specimens of Asphaltum can be obtained in small pockets 

 in this limestone here. 



* Loc jam cit. p 75. 



