As a result, all coal in the Phalen coal seam below 150 meters was to be " set aside to be mined by a new deep shaft mine, Number 2 ", also known as Number " 20 ".
42.
It is commemorated by a Michigan Historical Marker In 1998, the former owners of the mine donated the majority of the property of the Cliffs Shaft mine to the nonprofit group so that a museum could be created there.
43.
While still dominated by traditional shaft mining, the central Appalachian industry has turned increasingly to stripping, as air pollution rules have put a premium on the low-sulfur, cleaner-burning coal within a few hundred feet ( meters ) of the mountaintops.
44.
He is not against mining, he emphasizes, speaking as a veteran of the old deep-shaft mines where, he says, the work could be lethal but at least a man knew that his labors below were not literally erasing his place in the hollow.
45.
The site is significant as it represents the switch from open cast flint extraction favoured previously by prehistoric peoples who exploited deposits of flint close to the surface, to deep shaft mining which required more effort but produced more flint of a higher quality.
46.
Prior to that, there was scattered small-scale drift mining and surface mining of coal, but the construction of the first shaft mine ushered in an era which eventually led to as many as 290 significant mines and numerous other small ( " dinky " ) mines in the two counties.
47.
Around 1932, the H . C . Frick Coke Company closed and abandoned the Calumet Mine, located in nearby Calumet, Pennsylvania and sent a number of the miners to the Standard Shaft Mine near Mount Pleasant, and laid off the rest of the coal miners to fend for themselves, with no compensation or means of support.
48.
After the Township dissolved, Austhorpe stopped developing as quickly as it was doing, possibly due to the once abundant coal fields close to the surface which had been a major source of commerce for the area since Roman times becoming empty with deep shaft mining proving to be unsuccessful compared to the close by coal source at " Garforth ".
49.
The 1930s inter-war Great Depression in the United Kingdom saw the loss of almost half of the coal pits in the South Wales Coalfield, and their number declined further in the years following World War II . This number is now very low, following the UK miners'strike ( 1984 85 ), and the last'traditional'deep-shaft mine, Tower Colliery, closed in January 2008.
50.
The first ton of coal in a shaft mine 100 feet in depth and having a daily capacity of 600 tons frequently costs the mining adventurer upwards of $ 20, 000 ( 1888 ), and cases are on record where owing to the extraordinary amount of water in sinking, $ 100, 000 ( 1888 ) have been expended before coal was reached.
