Stratigraphical Geology. 75 



meagre calcareous representatives of the great limestone 

 formation of the central plain of Ireland, which has under- 

 gone a remarkable change in mineral characters and thickness 

 in this direction, in keeping with the general change which 

 the formation undergoes throughout the British Isles." 



The Ballycastle coalfield was considered by Sir Richard 

 Griffith as one of the oldest in the British Islands. In 

 1770, in pushing forward an adit towards a bed of. coal, 

 the miners struck an old working of considerable extent, 

 which branched out into thirty-six chambers. The antiquity 

 of this early working was such that even tradition had 

 nothing to say of it, though the passages indicated very 

 extensive workings in early times. The sides and roofs 

 of the passages were covered with sparry incrustations, and 

 in places the remains of old implements and decayed 

 baskets were found. 



Many attempts have been made to develop a trade in 

 connection with the Ballycastle coalfield, but no effort has 

 yet seemed to have succeeded in establishing itself on a 

 successful and permanent footing. 



The coal-bearing strata may be divided into three districts : 

 (i) Colliery Bay, extending from Ballycastle to Carrickmore 

 dyke; (2) Fair Head and Murlough Bay district; (3) the 

 Glenshesk and Carey river district. Each district is divided 

 from the others by dykes, while a number of faults traverse 

 each coalfield. The Great Gaw dyke, stretching from Bally- 

 castle to Murlough Bay, separates the first and third districts. 

 The Carrickmore dyke separates the first and second dis- 

 tricts. In the first district the sandstones are generally 

 yellowish; in the second district the sandstones are thicker 

 bedded and reddish, with a bed of purple limestone, and 

 are capped by the dolerite of Fair Head, which has also 

 intruded as sills into the sandstones ; in the third district 

 the prevailing beds are shales, with thin seams of coal and 

 limestone ; but in this district the rocks are generally covered 

 by glacial drifts and gravels. 



Owing to the number of faults and dykes, the dips of the 

 beds vary in the different sections, and the numerous dis- 

 placements have interfered with any extended efforts being 

 made to develop the natural resources of the district. The 



