Longwall mining is thought to have started in Shropshire, England in the 17th century and spread to the Midlands Collieries in the late 18th century.
Pre mechanisation days was done with a "hewer" undercutting the coal face with a small pick, and then his helper would either pry the coal down or wedge it down and load it into large baskets called "corves" to be hauled away by young girls and boys to pit bottom.
As machinery became available, undercutting machines started appearing on the market, either an air operated or later electric operated wheel type undercutting machines were used. Turn of the 20th century, American made "chain bar" machines were imported into UK collieries, most were failures due to the coal and conditions being totally different to US mines.
Eventually the Mavor Coulson company and Anderson Boyes developed bar chain under cutting machines to work in UK conditions.
From cutters came machines that would completely cut the coal and load it, first of these was the Meco-Moore Slicer, which started as just a coal cutter then progressed as a cutter/loader. Started out sometime in the 1930's and was developed into a successful machine by the 1950's.
Next was probably the trepanner, a floor mounted machine with two trepan heads to core the coal and several short jib cutters to square the face up. That was a true power loader machine.
During the 50's Anderson Boyes produced a drum shearer, but it was not a power loader, ie, the coal had to be ploughed onto the conveyor. Many attempts to turn the shearer into a power loader.
John Anderton was the one credited with the "invention" of the power loader as we know it today, it still bears his name as "The Anderton Power Loader" Or simply the shearer.
I was luckiy, in that when I started in the industry, mechanised faces were pretty new to the industry and have seen many innovations taken for granted today.
That's just a "very brief" history of longwall mining, I've not even touched on how "conventional hand got" faces operated, or how "cyclic" machines worked in practice, or plough faces work, nor touched on roof support. Would take many hours of typing!
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