) THE SOUTH WALES COALFIELD, & METHODS' | OF WORKING COAL IN ITS MINES
... ) THE SOUTH WALES COALFIELD, & METHODS OF WORKING COAL IN ITS MINES. The coalfield of Monmouthshire and South Wales extends from Pontypool on the east, by Llantrissant and Swansea, to Caermarthen Bay on the west, and around on its north outcrop by Llandybie, Hirwain, and Tre- degar to Pontypool. This portion of the coalfield is about 58 miles from east to west, with an average breadth of 15 ...