Page:Transactions of the Geological Society, 1st series, vol. 3.djvu/155



B. Transition Limestone.

The entrance of the noble bay of Carlingford is bounded on the south-west side by an obtuse point of land very low, and almost on a dead level, whence the Foy mountain boldly rises, falling away to the south towards Cooley, where it forms the ridge named Golding mountain.

The greater part of this flat point of land, ending on the north at Carlingford Castle, is occupied by a limestone formation which I am disposed to refer to that of transition.

It covers a square surface of about nine English miles, reappearing at the Block-house island in the middle of the bay, but I am not aware that there are any vestiges of it on the shore in the county of Down, which limits the north—east side of the bay.

The strata lean on the east side of the Golding mountain dipping to the south east: they however rise to a very inconsiderable height upon its abrupt declivity.

There are quarries opened in a continual line to the extent nearly of one English mile, at the foot of the Golding mountain, the depth of the quarries varying from fifty to eighty feet: limestone is raised besides in other places nearer to the shore, at Cooley, Mullaghtre, and the Gan rocks.

This limestone is remarkable, because it alternates both with transition trap and with greywacke slate; evidently so with the former at Cooley, and with the latter at the Gan rocks.

The solid strata are frequently traversed by veins and thin layers of calcareous spar: between them intervene many thinner beds passing into slaty marl.