DUCKENFIELD COLLIERIES. 



273 



won from bords, but most is obtained now-a-days from the 

 pillars. These collieries are under the management of Mr. 

 George Durie. 



The seam worked is the Bore-hole, which is from 3ft. 

 9in. to 4ft. 6111. thick. On account of being so low, the roof 

 has to be brushed to make headroom. It is worked on the 

 bord and pillar system; the bords being 8 yards and the 

 pillars six or eight yards wide. The method of extracting the 

 pillars depends principally on the nature of the roof. Cut- 

 throughs are made about 40 yards apart. If the roof is of 

 fairly good shale or sandstone, each alternate cut-through is 

 put in order, and a roadway made 011 the out-bye side of 

 tiie pillnr to be extracted; the roof of the bord is supported 

 with props, and any loose rock in the way thrown on one side. 

 A pair of men then take out a cut four yards wide off the far 



Fig. 177. Pillar Extraction, with fairly good roof, 

 end of the pillar, and rails are laid for the skips to run on. 

 The men then continue to work the face of the pillar as if it 

 was a bord, bringing the rails up to a convenient distance 

 as the work proceeds (Fig. 177) . 



Where the roof is bad and the bords fallen in, all the cut- 

 throughs have to be cleaned out and repaired. The pillar 

 is then worked forward from each side of the cut-throughs. 

 At first only four yards wide is worked, leaving a stump of 

 coal four yards in width, but the cut is gradually increased 

 till it is the full width of the pillar (Fig. 178). 'The object 

 is to extract half the length of the pillar between cut-throughs 

 from each starting point, but circumstances seldom permit of 

 this being accomplished. When a cut-through has fallen in, 

 the roof, at its sides, has to be supported on chocks. When 

 starting to extract the pillar of a district a commencement is 



