Wheal Busy


Heritage Category:
Scheduled Monument
List Entry Number:
Date first listed:
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The building or site itself may lie within the boundary of more than one authority.

Cornwall (Unitary Authority)
National Grid Reference:
SW 73830 44537, SW 73935 44829, SW 74219 44773

Reasons for Designation

For several millennia the western part of the South West Peninsula, namely Cornwall and West Devon, has been one of the major areas of non-ferrous metal mining in England. It is defined here as prospecting, extraction, ore processing and primary smelting/refining, and its more important and prolific products include copper, tin and arsenic, along with a range of other materials which occur in the same ore bodies. Throughout much of the medieval period most of the tin was extracted from streamworks, whilst the other minerals were derived from relatively shallow openworks or shafts. Geographically, Dartmoor was at the peak of its importance in this early period. During the post-medieval period, with the depletion of surface deposits, streamworking gradually gave way to shaft mining as the companion to openworking methods. Whilst mining technology itself altered little, there were major advances in ore processing and smelting technologies. The 18th century saw technological advances turning to the mining operations themselves. During this period, Cornish-mined copper dominated the market, although it was by then sent out of the region for smelting. The development of steam power for pumping, winding and ore processing in the earlier 19th century saw a rapid increase in scale and depth of mine shafts. As the shallower copper-bearing ores became exhausted, so the mid to late 19th century saw the flourish of tin mining operations, resulting in the characteristic West Cornish mining complex of engine houses and associated structures which is so clearly identifiable around the world. Correspondingly, ore processing increased in scale, resulting in extensive dressing floors and mills by late in the 19th century. Technological innovation is especially characteristic of both mining and processing towards the end of the century. In West Cornwall, these innovations relate chiefly to tin production, in East Cornwall and West Devon to copper. Arsenic extraction also evolved rapidly during the 19th century, adding a further range of distinctive processing and refining components at some mines; the South West became the world's main producer in the late 19th century. From the 1860s, the South West mining industries began to decline due to competition with cheaper sources of copper and tin ore from overseas, leading to a major economic collapse and widespread mine closures in the 1880s, although limited ore-extraction and spoil reprocessing continued into the 20th century. A sample of the better preserved sites, illustrating the technological and chronological range, as well as regional variations, of non-ferrous metal mining and processing sites, together with rare individual component features, are considered to merit protection.

Despite limited disturbance, the remains of Wheal Busy survive well. The complex of earthworks in the eastern area of the monument, and the Brunton calciner, are particularly well preserved. The various structures and earthworks represent well the range of mining activity here, and its development over time. The eastern complex is of outstanding importance for its visual impact and significance as a mining landscape; the pits and shafts illustrating the scale and methods of 18th century mining, and the reservoirs and leats showing the lasting importance and management of surface water resources. There is also great potential for buried remains associated with pioneering water, horse, and steam powered engines; the earliest of the series of major steam engines employed on the mine being sited within the monument. Overall, Wheal Busy provides an excellent example of a larger Cornish copper mine, which had a prolonged impact on settlement and transport patterns in the area.


The monument includes the remains of the copper and tin mine Wheal Busy, also known as Chacewater Mine and Great Wheal Busy, situated west of Chacewater on a tract of fairly high and flat country extending west from here through Scorrier. The location comprises level ground and slight slopes around the head of a shallow dry valley falling away to the south. Also included in the scheduling are traces of World War II military activity. The mining remains in this monument are associated with others nearby. The arsenic works is also a listed building, Grade II. The monument is divided into three separate areas of protection. The history of Wheal Busy is long and varied. Contemporary accounts, maps, and other documents significantly enhance our understanding of the site. These sources show that this was the most productive of the Scorrier copper mines. In the 18th century in particular it was large and intensive, and its development is marked by the adoption of new pumping engine technologies. These innovations were necessitated by the lack of surface water for power, which led to a notorious conflict with another mine in 1811, and by particularly wet conditions underground. They were made economically viable by the richness of the lodes. The area is crossed by mineral lodes running roughly east-west. Small-scale tin mines are thought to have been active here in the 17th century, when the ground was largely open downs and around the turn of that century, copper was found as the ore bodies were worked at greater depths. By the 1720s the mine incorporated several earlier works, with most leased by John Coster and his son of the same name. The Coster's introduced or adapted large waterwheels and horse-powered whims or winding engines to Cornish mines to improve the drainage critical to their development at this time. Around 1710 a new water driven rag-and-chain type pump was introduced here, on the edge of the Pittslouarn or Wheal Busy section, thought to lie in the eastern area of protection. Again in this area, around 1725, one of Cornwall's first Newcomen atmospheric or true steam powered pumping engines was erected by Joseph Hornblower. Another such engine was working nearby by the mid-18th century. In the 1770s the mine acquired a Smeaton improved atmospheric engine and Cornwall's first Boulton and Watt condensing engine, both exceptionally powerful. Through most of the early 19th century the mine prospered, tin becoming an important product around 1857. The name Wheal Busy was extended to the whole mine around 1823. In 1856 the engine house in the north-western area of the monument was built for a Harvey's engine. Mine plans show dressing floors for ore processing in the west part of the main area of the monument, and later, near its south-west area. They also mark the mine count house or office and other service buildings, near the smithy. The smithy building is a listed building and is not included in the scheduling. For some years around 1860 the mine incorporated several others to the north-west, as Great Wheal Busy. Growth was halted in 1866 by the collapse of copper prices. The mine was rich in arsenic, and was reopened for this in several phases until closure in 1928. In 1909 another engine was placed in the 1856 house; the secondary boiler house (which does not form part of this monument) was also built at this time. The two successive arsenic works were sited south of the core of the mine to reduce the nuisance from their fumes. After extraction ended, some spoil was reprocessed for arsenic and wolfram. The historical sources show that the underground development of the mine was pursued systematically from the time of the Coster's with the driving of slightly inclined tunnels known as adits, to drain water as well as providing ventilation and access to the lodes. Numerous shafts were sunk, some designed to allow connecting adits to be driven from several points at once. In 1778 the workings were linked to the Great County Adit (Cornwall's most extensive drainage tunnel network) discharging some 3.5km south east. At the end of the 18th century the main lodes were exploited throughout the length of the mine. Shaft names changed frequently, reflecting the growth and evolution of the mine. In its prime, Wheal Busy was a major Cornish employer, requiring many surface workers for the hand breaking and sorting of copper ore, as well as miners. The mine contributed greatly to the development of the village, and new parish, of Chacewater. It also influenced regional transport networks, for example, sending ore to be shipped for smelting by road to both coasts of Cornwall in the 18th century, then using a pioneering horse drawn tramroad to the north coast. The eastern part of the monument survives as a complex palimpsest of earthworks, some superimposed, developed over several centuries. It is characterised by numerous early post-medieval lode back pits, which are shallow shafts accessing the upper part of a lode; aerial photographs show how they form lines following the ore lodes. Deeper shafts with adjacent spoil heaps are visible towards the centre, south, and west. Those in the centre are associated with the name Pittslouarn and with early steam engine sites, and remains of an engine house, possibly of 1868, are visible here. At least one shaft has an adjoining horse whim platform. Earthworks for managing water are another feature of this area. Reservoirs, retained by dams or fully enclosed by banks, are connected to leats, some diverted around pre-existing earthworks. These will have provided water power, or supplied steam engines. On the north-west of the area is a cluster of pools for different functions, built up over time. This group seems to have expanded over dressing floors, remains of which can be expected to survive below ground level. Also in the area, on its south-west, are traces of the flue and chimney of the earlier arsenic works. The area on the north-west of the core area of the monument includes the 1856 pumping engine house, with the site of its first boiler house on its east side, and the shaft it served, Engine Shaft, on its south side. The engine house stands to roof level, retaining the wall openings, internal ledges, bedstone, and other features designed to admit and support the steam engine with its cylinder and rocking beam. Its fabric is local slate stone, with granite at load bearing points, and brick details. The detached chimney is of early telescope-like form and is built of stone and brick. The original boiler house is visible as an earthwork (its stone was probably reused for its successor). Engine Shaft itself is typical of pre-20th century shafts in that it descends at an angle, slanting to the north along the tilt of the lode so that it passes under the engine house. It extends to the maximum depth of the mine. The 1900's arsenic works is in the south-west area of the monument. A Brunton calciner for roasting ore to produce arsenical vapour stands to roof level. The structure is of massive granites bound by iron ties, with a brick front retaining iron door fittings. The revolving ore bed and other machinery survive within. West of this are substantial remains of a second, shaft type furnace and beyond, a double labyrinth where arsenic was recovered from the vapour, with much of the stone walling forming its multiple condensing chambers visible. Beyond this are a final scrubbing chamber, and the near intact tall chimney of stone and brick which vented the waste fumes. Much of the ground in the arsenic complex is raised and will contain associated deposits. In World War II a large temporary US army camp was sited in the centre of Wheal Busy. Aerial photographs show trenches and vehicle tracks of this period in the eastern area of protection, probably used for training by the troops. All modern fencing and safety barriers, gates and gate fittings, waymarkers, and vehicular access blocking rocks, are excluded from the scheduling, although the ground beneath these features is included.

MAP EXTRACT The site of the monument is shown on the attached map extract.


The contents of this record have been generated from a legacy data system.

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Books and journals
Barton, D B, A History of Copper Mining in Cornwall and Devon, (1961)
Barton, D B, A History of Tin Mining and Smelting in Cornwall, (1965)
Barton, DB, The Cornish Beam Engine, (1969)
Borlase, W, Natural History of Cornwall, (1758)
Buckley, J A, The Great County Adit, (2000)
Rowe, J, Cornwall in the Age of the Industrial Revolution, (1953), 39
Brooke, J , 'The Kalmeter Journal' in The Kalmeter Journal, (2001)
Brown, K, Acton, B, 'Exploring Cornish Mines' in Exploring Cornish Mines, , Vol. 2, (1995), 47-64
Dines, H G, 'The Metalliferous Mining Region of South-West England' in The Metalliferous Mining Region of South-West England, , Vol. 1, (1956), 389
Hamilton Jenkin, AK, 'Around Gwennap' in Mines and Miners of Cornwall, , Vol. 6, (1963), 43
Plan and drawings at HES, CCC, Sharpe, A, Wheal Busy arsenic works, (1990)
PRN 53834, Young, A, Cornwall SMR, (2000)
Report at HES, CCC, Sharpe, A .et al, Engine House Survey The Mineral Tramways Project, (1991)
Title: Cornwall Mapping Project Source Date: 1999 Author: Publisher: Surveyor:
Title: Great Huel Busy Abandoned Mine Plan Source Date: 1864 Author: Publisher: Surveyor: CRO R 151A
Title: Map of Chacewater Mine Source Date: 1813 Author: Publisher: Surveyor: CRO X397/91. Reproduced source 8 p57


This monument is scheduled under the Ancient Monuments and Archaeological Areas Act 1979 as amended as it appears to the Secretary of State to be of national importance. This entry is a copy, the original is held by the Department for Digital, Culture, Media and Sport.

End of official listing

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