Wheal Vor

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Wheal Vor
Location
Wheal Vor
Location in Cornwall
Location Helston
County Cornwall
Country U.K.
Coordinates 50.1179°N 5.3266°W / 50.1179°N 5.3266°W / 50.1179; -5.3266Coordinates: 50.1179°N 5.3266°W / 50.1179°N 5.3266°W / 50.1179; -5.3266
Production
Products Copper and Tin
History
Opened 15th century
Closed c.1910

Wheal Vor was a metalliferous mine about two miles north west of Helston and one mile north of the village of Breage in the west of Cornwall, England, U.K. It is considered to be part of the Mount's Bay mining district.[1] Until the mid–19th century the mine was notable for its willingness to try out new innovations. Although very rich in copper and tin ores, the mine never lived up to its expectations, and during the later part of the 19th century had several periods of closure.

Geology

The country rock at the mine is killas, mostly hard, blue-grey rock. The mine's main produce was copper and tin derived from the nearby Tregonning-Godolphin granite, part of the Cornubian batholith. There were four main lodes at the mine, two of which were crossed by two wide elvan dykes, 20 and 48 ft (6.1 and 14.6 m) wide. At the intersections the lodes widened and mineralization spread through the dykes, forming irregular masses which were stoped to the full width of the dykes.[2]

Early history

Wheal Vor is an ancient mine: the ground shows the remains of old surface excavations following the lodes, and mining may have taken place here in late Roman times.[3] The underground mine probably started in the 15th century and continued until 1715, producing mainly copper ore.[4] The mine was associated with the Godolphin family who were keen on trying out recent innovations, and through their connections it may have been the first mine in Cornwall to make use of gunpowder, at the close of the 17th century.[5]

Shortly after 1700 the mine may have been one of the few sites to trial Thomas Savery's pump,[6] which was, according to his patent application, "A new invention for raiseing of water … by the impellent force of fire, which will be of great use and advantage for drayning mines…". It is not certain whether Savery's experiments took place at Wheal Vor or at another nearby mine, but it is known that c. 1710 a Newcomen engine had been installed here, which was probably the first in Cornwall.[7][8]

Other innovations that were trialled at the mine included the second Woolf engine in the county (1815);[9] one of the first Brunton Calciners (1830);[10] and an early man engine (c. 1856).[11] It also one of the few mines to operate its own smelter, having taken over the one owned by the Cornish Copper Company (a major shareholder) in 1823 and later moving to the mine.[6]

The years between 1812 and 1848 were the mine's most successful, and it was for a time the richest mine in Cornwall. The ore raised from the 274 fathom[notes 1] (501 metres) level contained on average 5% tin, instead of the 1–1.5% that was usually found in Cornish mines,[12] and for some time after the discovery of this rich lode the mine regularly produced 200 tons of white tin per month.[4] In 1840 the mine was employing 1,174 people, but it closed between 1848 and 1853.[12]

1850 onwards

In 1854 a 100-inch (2.54 m)[notes 2] steam engine, the largest in Cornwall at the time,[6][12] was installed on Crease's shaft[notes 3] for draining the mine. This engine was built by Harvey & Co of Hayle (the other main shareholder in the mine) and its starting was accompanied by a large celebration. But by 1860, it and another 85-inch (2.16 m) were using 600 tons of coal a month, which was determined to be unsustainable so both engines were stopped and later sold.[6]

From a peak production of over 840 tons of black tin in 1865 and 1866, the output from the mine declined until in 1877 only 13 tons was produced. The mine was then apparently idle until 1881, when five people were working there. From then until 1885 up to 22 people were employed, though only minimal amounts of ore were sold. There was another gap until 1906, when 65 people were recorded as working at the mine, 16 of them underground. The mine produced some black tin between 1907 and 1910, but then evidently closed again,[13] probably due to difficulty keeping water out of the mine.[4] In 1967 another attempt was made to reopen the mine, but it came to nothing.[12]

Wheal Vor was the main component of the "Great Wheal Vor United" group of mines, which included among others, Polladras Mine, Penhale Wheal Vor, Wheal Metal and Sithney Wheal Metal. Wheal Vor also took over the mining setts of two other mines: Carleen Mine (otherwise known as West Wheal Vor), and Wheal Vreah.[2]

Today, there is little visible above ground of the once extensive sett of the mine. An engine house and chimney are the most obvious remains.[6]

Notes

  1. ↑ A "fathom" is equal to six feet (about 1.83 metres). At the time fathoms were the standard way of expressing depth in mines.
  2. ↑ This refers to the diameter of the cylinder. It was the standard way of determining the size, but not necessarily the power, of steam engines.
  3. ↑ Crease's shaft was named after Henry Pering Pellew Crease, the company chairman at the time.[1]

References

  1. ↑ Dines 1956, p.169.
  2. ↑ 2.0 2.1 Dines 1956, p.224.
  3. ↑ Dines 1956, p.227, citing James, C.C. 1945. Great Wheal Vor, Trans. Roy. Geol. Soc. Corn., vol, xvii, pp. 194–207.
  4. ↑ 4.0 4.1 4.2 Dines 1956, p.227
  5. ↑ Earl 1994, p.42.
  6. ↑ 6.0 6.1 6.2 6.3 6.4 Hancock 2008, pp.131–132
  7. ↑ Earl 1994, p.38
  8. ↑ L T C Rolt and J S Allen, The steam engine of Thomas Newcomen (3rd edn. Landmark, Ashbourne 1997), 44, from R L Galloway, The steam engine and its inventors, quoting a paper by Joseph Carne on the history of copper mining in Cornwall.
  9. ↑ Barton 1966, p.37
  10. ↑ Earl 1994, p.93
  11. ↑ Barton 1966, p.210
  12. ↑ 12.0 12.1 12.2 12.3 "Mines of the Tregonning-Godolphin Granite - Great Wheal Vor". Cornwall in Focus. Retrieved 2009-07-30. 
  13. ↑ Burt et al. 1987, pp.548–549

Sources

  • Barton, D. B. (1966). The Cornish Beam Engine (New ed.). Truro: D. Bradford Barton Ltd. 
  • Burt, Roger; Waite, Peter; Burnley, Ray (1987). Cornish Mines: Metalliferous and Associated Minerals 1845–1913. University of Exeter. ISBN 0-85989-287-5. 
  • Dines, H. G. (1956). The Metalliferous Mining Region of South-West England. Volume I. London: HMSO. pp. 224–227. 
  • Earl, Bryan (1994). Cornish Mining: The Techniques of Metal Mining in the West of England, Past and Present (2nd ed.). St Austell: Cornish Hillside Publications. ISBN 0-9519419-3-3. 
  • Hancock, Peter (2008). The Mining Heritage of Cornwall and West Devon. Wellington, Somerset: Halsgrove. ISBN 978-1-84114-753-6. 
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