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complete, and the getting of coal from the banks, betwixt the 
board-gates already driven, may commence, and be carried 
on concurrently with the driving of the remaining board- 
gates. By driving the board-gates entirely through the 
coal to the communication with the furnace and up-cast, some 
time before the coal is got, a large proportion of the gas — 
one-half at least — is, by the action of the air and furnace, 
drained off from the "backs" and " vertical cracks" in the 
coal. These backs or cracks are nearly always north and 
south, and nearly at right angles with the dip and rise of 
the coal, and are intersected by the board-gates. These 
drifts, with a continuously ascending ventilation through 
them, I hold to be the best, indeed I may say the only 
means of insuring the safety of a coal mine, as with very 
small attention on the part of the bottom steward, no 
accumulation of gas can take place. 
As soon as the board-gates are all driven, the regular 
getting of coal to the fullest extent from all the banks may 
be carried on ; and I strongly recommend what is termed 
" long work " in wide double banks, and that the coal should 
be wrought downwards from the cross heading and up- 
cast pit and furnace. This mode of working possesses many 
advantages ; by it much straight work is saved, and, con- 
sequently, waste of coal prevented ; a much larger pro- 
portion, probably 20 per cent, or one-fifth more of round 
or best coal is got from the same seam, and a large saving 
altogether of the coal usually left as posts and pillars, and 
after the first fall at the commencement of a bank, the roof 
breaks or expands itself down more equally and quietly, 
causing less concussion of the gas that may be in it. 
I do not recommend what are called pack walls, to prevent 
the roof coming down. I have frequently seen in collieries 
such an extent of these walls, as greatly to obstruct the 
circulation of air, and at the same time causing a serious 
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