|The unofficial coalpits in South Croft have already been men- tioned. One of the reasons why the villagers were ordered to fill them up may have been that they were competing
with Sir William Savile's coal mines in Brierley. These were in the area of Gill Croft and Pitt Croft. The nature of the documents dealing with these mines suggests that they were bell pits or shallow drift mines. A bell pit was sunk to a coal seam just
a few feet from the surface. The coal was then dug out to form a bell-shaped chamber, from which the mines get their name. No kind of propping was used, so that when the roof became unsafe the pit had to be abandoned. Another pit was then sunk close by
to continue working the coal seam. Drift mines were usually sunk into the hillside to follow coal outcrops underground; these again were worked until they became unsafe. Timbering was used in these larger mines, and in 1638, one pound thirteen shillings
was paid out for pit props in the mines of Brierley. In the same year, eighteen shillings and sixpence was paid for the fixing of a water pump in a pit at Gill Croft, probably to divert water from a spring
It is possible that the re-discovery of these chambers and tunnels of these early coal mines has led to so many 'secret tunnel' legends abounding in the area. The pits in Gill and Pitt Crofts were worked mainly by Robert Hemingway on behalf of Sir William Savile, and in 1638, the total amount paid out in these mines was fortyfive pounds seven shillings and eleven pence. This was broken down into accounts such as 'Paid to Robert Hemingway for the drawings of one pit in the bottom of Gill Croft eight shillings and sixpence'. to John Law and others-two shillings'. On the 26th October, 1641, these pits were leased to William Speight for a period of ten years, for thirty pounds per year. William Speight also leased a messuge with lands in the village for thirteen years at £28 per year.
One hundred yards to the south-east of Lindley House is a deep ravine at the head of which is a subsided mouth of a long-disused this could well be the mine from which Pitt Croft received its name. Nearby, in a field to the south of this, is the subsidence drift-mine and one bell pit. Further downstream, past the sewage works, are the remains of three small drift-mines. These are just above the water-line of the now dry upper milldam mentioned elsewhere. All five mines were dug in a north-westerly direction into coal seam called Brierley Coal. This can be seen to outcrop near one of the old mines. The over-lying sandstone is known or Brierley Rock. The land to the north of Ket Hill Lane Pitt Hill and may have been the site of yet another coal mine in Brierley, though there are no signs of workings.