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18-598: The Great Haigh Sough is a tunnel or adit driven under Sir Roger Bradshaigh's estate between 1653 and 1670, to drain his coal and cannel pits in Haigh on the Lancashire Coalfield . The sough 's portal and two metres of tunnel from where it discharges water into the Yellow Brook at Bottling Wood is a scheduled monument . Cannel coal had been dug from bell pits on Bradshaigh's estate since

36-704: A detailed survey of the construction of the sough and its shafts with instructions for maintenance so that, "the benefit of my 16 years labour, charge and patience (which it pleased God to crown with success for me and my posterity) may not be lost by neglect." The 1,120 yards (1,020 m) long tunnel, up to six feet wide and four feet high, had ten ventilation shafts each up to 3 yards (2.7 m) wide and up to 49 yards (45 m) deep. Driven from Bottling Wood to Park Pit, work started in 1653 and finished in 1670. The miners used picks, hammers, wedges and spades and would have encountered blackdamp which would have extinguished their candles warning them of its presence. The sough

54-428: A mine where the local topography permits. There will be no opportunity to drive an adit to a mine situated on a large flat plain, for instance. Also if the ground is weak, the cost of shoring up a long adit may outweigh its possible advantages. Access to a mine by adit has many advantages over the vertical access shafts used in shaft mining . Less energy is required to transport miners and heavy equipment into and out of

72-657: Is about ten miles (16 km) long. Other examples are the Great County Adit in Cornwall, a 40-mile (64 km)-long network of adits that used to drain the whole Gwennap mining area, and the 3.9 miles (6.3 km) Sutro Tunnel at the Comstock Lode in Virginia City , Nevada . A side benefit of driving such extensive adits is that previously unknown ore-bodies can be discovered, helping finance

90-482: Is defined by the deepest open adit which is known as the "drainage adit". The term mine drainage tunnel is also common, at least in the United States. Workings above this level (known as "above adit") will remain unflooded as long as the adit does not become blocked. All mine workings below both the drainage adit ("below adit") and the water table will flood unless mechanical means are used for drainage. Until

108-493: The Coal Authority provided a passive treatment plant in a scheme costing £750,000. Work was undertaken by Ascot Environmental who built a pumping station, pipelines, settlement lagoons, and reedbeds and landscaped the site. The scheme has improved the water quality, removed manganese and iron which caused the discolouration and allowed fish to repopulate the brook. Bibliography Adit Adits are driven into

126-531: The River Douglas downstream, with ochre deposits. Water infiltrated the pits by percolating through the overlying porous rock strata containing bands of ironstone , not via the shafts. After heavy rain in December 1929, 561,600 gallons of water drained from the sough into the brook at a rate of 290 gallons per minute. In 1978 the rate was 352 gallons per minute, more than 500,000 gallons per day. In 2004

144-477: The 14th century where the seam was very close to the surface near the Old School Cottages. The sough was driven to drain the pits, which produced both coal and cannel and extended the life of their shallow workings, which were prone to flooding. The sough, a major investment, was considered preferable to winding water from the workings by the primitive methods available at the time. Bradshaigh recorded

162-421: The higher temperature underground and will naturally exhaust from vertical shafts, some of which are sunk specifically for this purpose. Most adits are designed to slope slightly upwards from the entrance so that water will flow freely out of the mine. Mines that have adits can be at least partly drained of water by gravity alone or power-assisted gravity. The depth to which a mine can be drained by gravity alone

180-515: The invention of the steam engine this was the main restriction on deep mining. Adits are useful for deeper mines. Water only needs to be raised to the drainage adit rather than to the surface. Because of the great reduction in ongoing costs that a drainage adit can provide, they have sometimes been driven for great distances for this purpose. One example is the Milwr tunnel in North Wales, which

198-421: The main drive to Haigh Hall, were worked as small collieries and the rest filled in. The first shaft from the outfall, Cannel Hollows Pit, was 23 feet (7.0 m) deep. The fifth shaft, Sandy Beds Pit, was sunk 30 yards (27 m) to the sough and met the coal seam at 14 yards (13 m). Its shaft was rectangular in section but the others were round. The last shaft before Park Pit was 48 yards (44 m) deep to

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216-423: The mine. It is also much easier to bring ore or coal out of the mine. Horizontal travel by means of narrow gauge tramway or cable car is also much safer and can move more people and ore than vertical elevators. In the past horses and pit ponies were used. In combination with shafts, adits form an important element in the ventilation of a mine : in simple terms, cool air will enter through an adit, be warmed by

234-429: The side of a hill or mountain, and are often used when an ore body is located inside the mountain but above the adjacent valley floor or coastal plain. In cases where the mineral vein outcrops at the surface, the adit may follow the lode or vein until it is worked out, in which case the adit is rarely straight. The use of adits for the extraction of ore is generally called drift mining . Adits can only be driven into

252-626: The sough and a payment was made for repairing the hoppets (buckets) used to haul debris up the nearest shaft. Regular inspections were carried out until 1923 and its abandonment ultimately led to the flooding of the Aspull and Westhoughton pits in 1932. Supporting pillars of cannel were accidentally ignited in the Cannel seam in March 1737 and the underground fire was still burning in the October despite

270-629: The sough and met the Cannel seam at 32 yards (29 m). The shaft at Park Pit was 46 yards (42 m) to the sough and met the King Coal seam at 41 yards (37 m). In the 18th century the sough was extended and other levels were driven to connect new pits as they became operational. Some pits had their own soughs. The sough was extended to Fothershaw Pit in about 1856 and, by the Wigan Coal and Iron Company , to Aspull Pumping Pit after 1866 extending its length to 4,600 yards (4,200 m). Such

288-496: The ventilation shafts being covered. The fire was eventually extinguished in 1738 after the sough was dammed and the workings flooded. The sough's entrance portal is constructed from brick and stone and leads into a brick-lined culvert . The portal and 2 metres (6 ft 7 in) of the culvert is a scheduled monument . The sough discharged iron-rich minewater into the Yellow Brook in Bottling Wood, discolouring it, and

306-474: Was completed without using explosives but it is possible that fires were lit against the rock at the end of a shift to help break it. The shafts were used to remove rock as the miners cut the tunnel. Progress averaged 66 yards (60 m) per year or about 4 feet (1.2 m) a week. Between its outlet and Park Pit the sough passed through several layers of hard sandstones , mudstones and the Cannel and King Coal seams. Seven ventilation shafts, roughly aligned with

324-455: Was the importance of the sough that in 1687, the estate bailiff, Thomas Winstanley, ordered its inspection and cleaning from bottom to top at least every two months and "the least decay thereof in any place speedily and substantially repaired". Cleaning involved clearing small rock falls and removing the build-up of deposited ochre ( Hydrated iron oxide ). It was inspected 14 times between 1759 and 1767 and in 1768 workmen spent 49 weeks cleaning

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