Round Island Light, Isles of Scilly

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Round Island Lighthouse
Round Island(Scillonia)2.jpg
Round Island, Isles of Scilly
Location Round Island, Isles of Scilly, England
Coordinates 49°58.7′N 06°19.35′W / 49.9783°N 6.32250°W / 49.9783; -6.32250Coordinates: 49°58.7′N 06°19.35′W / 49.9783°N 6.32250°W / 49.9783; -6.32250
Year first constructed 1887
Year first lit 1887
Automated 1987
Construction Granite
Tower shape Circular
Markings / pattern White
Height 19 metres (62 ft)
Focal height 55 metres (180 ft)
Current lens 360MM Revolving Optic
Intensity 42,945 Candela
Range 24 nautical miles (44 km; 28 mi)
Characteristic One white flash every 10 seconds
Fog signal 4 Blasts Every 60 Seconds
ARLHS number ENG 118

Round Island Lighthouse (Cornish: Golowji an Voth, the hump lighthouse), in the Isles of Scilly was designed by William Tregarthen Douglass for Trinity House and completed in 1887. At the time of building it was one of three lights in the Isles of Scilly, the others being the Bishop Rock and St Agnes lighthouse. The light was modernised in 1966, automated in 1987 and the island designated as a Site of Special Scientific Interest (SSSI) in 1995. It is now managed by the Isles of Scilly Wildlife Trust, and except for the maintenance of the Grade 2 listed lighthouse, landing is not allowed.[1][2]

History[edit]

A cairn or burial chamber was destroyed when the lighthouse was built. Cairns on the Isles of Scilly date back to the Bronze Age and at that time Round Island was probably a peninsula on the northern shore of the main island in the Isles of Scilly. The granite, ashlar, 19 metres (62 ft) tall tower was designed by William Tregarthen Douglass, chief engineer for the Commissioners of Irish Lights and is built on a 35 metres (115 ft) tall mass of Hercynian granite. At the time of building the only access was up a flight of steps cut out of the rock and supplies were taken up the rock face by an aerial hoist.[1] Within the walls of the lighthouse the keepers tended a small vegetable garden, for which the soil was transported to the island.[3]

The light has a focal plane of 180 feet, and originally had an enormous hyperradial optic 4.6 metres (15 ft) high and weighing more than 8 tons. It was built by Chance Brothers & Co of Birmingham and, said at the time, to be ″ .... in relation both to size and character .... the most remarkable works of their kind hitherto achieved.″ A similar optic was installed for the Bishop Rock light the previous year. The optic was replaced in 1966 when the lighthouse was modernised, and again in 1987 when the light was automated. The light now has a 360 millimetres (14 in) optic which emits one white flash every ten seconds, has an intensity of 340,000 candela and a range of 44.5 km (24 nautical miles). The fog signal sounds four blasts every minute.[1][4] Gusts of winds can be ferocious such as in 1954 when there was continuous gales from 29 November to 16 December. Wind velocities of 177 kph (110 mph) were recorded at the Bishop Rock where seas raced past the window, and on Round Island the wind gauge was destroyed at 177 kph.[5]

Wildlife and ecology[edit]

Round Island was designated a Site of Special Scientific Interest in 1995 as part of the Pentle Bay, Merrick and Round Islands SSSI. The island is important for its breeding seabirds, especially the European Storm–petrel (Hydrobates pelagicus).[6] Breeding Storm–petrels were unrecorded on Round Island for many years, until one of the lighthouse keepers, mystified by the nightly appearance of black feathers in the living quarters, decided to keep some. When the identity of the bird was discovered, the cat was banished.[7] The Seabird 2000 survey counted 183 occupied nests and a follow–up survey in 2006 found 251 occupied nests on the island; the second highest total in the Isles of Scilly.[7][8] Puffins (Fratercula arctica) were first recorded as breeding on Round Island in 1850 by Issac North and during the building of the lighthouse it was said that ″They (puffins) were extremly tame and used to walk in and out of the kitchen of the workmen who built the tower. This tameness, and the edibility of their eggs, proved their undoing, for none survive now″.[9] [4] The seabird survey in 2000 also recorded 34 occupied nests of Manx Shearwater (Puffinus puffinus).[10]

Permission is needed from Trinity House to land on the island and only two botanists are known to have visited. The first, J. E. Lousley, in 1957, only recorded the invasive Hottentot fig (Carpobrotus edulis). Thirty years later, in 1987, Rosemary Parslow found much of the ground between the buildings and the cliff edge was covered in a carpet of purple dewplant (Disphyma crassifolium) and Hottentot fig. She also recorded a small number of the expected coastal species. They were sea spleenwort (Asplenium marinum), bird’s–foot trefoil (Lotus corniculatus), spear–leaved orache (Atriplex prostrata), sea beet (Beta vulgaris subsp. maritima), rock sea spurrey (Spergularia rupicola), thrift (Armeria maritima) and tree mallow (Lavatera arborea).[3]

See also[edit]

References[edit]

  1. ^ a b c Jones, Robin (2011). Lighthouses of the South West. Wellington, Somerset: Halsgrove. ISBN 978 0 85704 107 4. 
  2. ^ "Islands which are permanently or seasonally closed to protect wildlife". Isles of Scilly Wildlife Trust. Retrieved 8 April 2012. 
  3. ^ a b Parslow, Rosemary (2007). The Isles of Scilly. London: HarperCollins. ISBN 978-0-00-220151-3. 
  4. ^ a b Noall, Cyril (1968). Cornish Lights and Ship-wrecks. Truro: D Bradford Barton. 
  5. ^ Lousley, J E (1971). The Flora of the Isles of Scilly. Newton Abbot: David & Charles. ISBN 0-7153-5465-5. 
  6. ^ "Pentle Bay, Merrick And Round Islands". Natural England. Retrieved 8 April 2012. 
  7. ^ a b Robinson, Peter (2003). The Birds of the Isles of Scilly. London: Christopher Helm. ISBN 0-7136-6037-6. 
  8. ^ Webber, Julie. "Condition of SSSI units". Natural England. Retrieved 28 May 2012. 
  9. ^ North, Issac William (1850). A Week in the Isles of Scilly. London: Longman and Co. 
  10. ^ "Response rates to tape playback of male calls by Manx Shearwaters". JNCC. Retrieved 18 November 2012. 

External links[edit]