322 Mr. Buddle on Mining Records. 



and is 10 feet below. The D, E and F Pits are all 8 feet diameter to the 

 Main Coal. 



From the Main Coal to the Bensham, the A Pit was sunk 12 feet dia- 

 meter, but was subsequently walled up to the Metal Coal, and reduced to 

 10 feet diameter. 



The B Pit is sunk 8 feet diameter from the Main Coal to the Bensham 

 Seam. The C Pit was sunk 10 feet diameter from the Main Coal to the 

 Bensham, but was afterwards walled up to the Metal Coal and reduced to 

 8 feet. 



It became necessary to wall those pits, from the Bensham up to the Me- 

 tal Coal Seam, as the Metal Stone in the Shaft Walls would not stand the 

 heat of the furnace which it was necessary to place in the Bensham Seam. 



The Plan (Plate XV.) which accompanies this memoir shews the workings 

 of the Main Coal Seam, and the state in which it was left in April, 1831. 

 The G Pit was sunk with an engine as a separate winning, the shaft, 12 feet 

 diameter, and is divided by a three-tailed brattice into two coal shafts and 

 an engine shaft. The explanations on the Plan shew those parts of the 

 Main Coal Seam which are completely worked out, and the extent of 

 crushed or crept pillars which are not worked out, and which may, event- 

 ually, at some future period, be worth working. 



6. — System of Working. 



In the first opening of the Colliery the working of Pillars, technically 

 called working the broken, was not contemplated, as, at that period, the 

 working of a fiery colliery in the broken was not deemed practicable. As 

 much of the coal was, therefore, wrought out by the first working, called 

 working the ivhole mine, as it was thought safe to take, without running 

 the risk of shutting up the colliery by a creep ; that is to say, no more 

 coal was left in the pillars than was deemed barely sufficient to support the 

 roof. 



The winnings were, therefore, made 12 yards, viz., 4 to the board and 8 

 left in the wall or pillar, the walls being holed at 22 yards, 2 yards wide, 

 consequently if parts, or say 39 per cent., were obtained, and %% or 61 per 

 cent, were left in pillars. About a third of the colliery was worked in 



