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MINING COAL - METHODS -
Pillar and
Stall
In pillar and stall workings, coal was removed from large
areas underground, but much of the coal was left behind. These
were the pillars that supported the roof of the mine and
normally prevented the mine from caving in as the miners cut
deeper into the coal seam. Sometimes these pillars were
removed after the main parts of the seam had been extracted.
Tunnels and workings also required timbers or "pitprops"
which supported the rocks above and prevented smaller
rocks from falling onto the miners.
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