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Trevose Head Lighthouse
Trevose Head Lighthouse is a lighthouse on Trevose Head on the north Cornish coast at grid reference SW850766 lying to the WSW of Padstow[3] and was sited here as there was previously no light from Land's End to Lundy[4] and it would be visible from Cape Cornwall to Hartland Point.[5] The tower is 89 feet (27 m) tall, and has a range of 20 nautical miles (37 km; 23 mi), but, on a clear night, it can be seen from Pendeen Lighthouse, over 35 miles (56 km) away.[citation needed] History ConstructionThe site was surveyed by order of the Trinity Board in July 1844 with a design submitted that November and approved February 1845. Building began in that May with the laying out of the road and contract entered into with the builders the next month.[4] During gales on 20–21 November 1846 scaffolding attached to the tower was blown away.[6] After completion of the first tower, it was determined that the light was under certain circumstances liable to be mistaken by mariners. A second lower light[7] was therefore proposed and (the decision having been taken in June 1847) it was constructed, 50 feet in front of the first light, with a covered passage between them for use by the lighthouse keepers.[4] Only the first built 'high' light now remains. Designed by engineer James Walker[7] the two original lights, 'high' and 'low', were constructed under the supervision of Henry Norris[7] by builders Jacob & Thomas Olver of Falmouth.[8][4][7] They were provided with a pair of first-order fixed optics by Henry Lépaute of Paris[7] and each had an oil lamp with 4 concentric wicks manufactured by Messrs. Wilkins & Co. of Long Acre.[4][7] The light was first lit on 1 December 1847.[7][9] Later developmentsIn 1882, under Engineer-in-Chief James Douglass, the 'high' light was changed to an occulting light, now with a six-wick lamp, and the 'low' light was put out of use.[10] Under the new arrangement the high light was eclipsed (for three seconds) three times in quick succession every minute.[11]  From 1911 a series of further improvements were made. First, the keepers' dwellings were upgraded.[10] Then, in 1912 the light was again updated and the current rotating optic (weighing 3.6 tons) was installed.[12] At the same time, the addition of a red filter to the lamp meant that (as from 1 August 1912) the lighthouse displayed one short red flash every five seconds.[13] Work also began on installing a fog signal: a 5-inch siren attached to a 36-foot-long acoustic horn, which came into service in 1913; it was nicknamed 'Lord Rayleigh's trumpet' after its designer, the eminent physicist and acoustician.[14] The trumpet and siren were built on to the roof of a new engine house, containing a pair of Hornsby oil engines, the air compressor, reservoirs and other equipment. In 1920 a paraffin vapour burner replaced the oil lamp; it continued to show one red flash every 5 seconds. The fog signal equipment all remained in service until 1963, when the trumpet and siren were replaced by a set of eight 'supertyfon' air horns mounted in a metal turret on top of the engine house. New diesel engines and Reavell compressors were provided.[14] The light was electrified in 1974.[10] In 1995 the lighthouse was automated and became unmanned.[15] The red colour was removed from the light at this time and the rotation speed of the optic was slowed.[10] By this stage the engine house was suffering cracking due to erosion; with automation a new fog signal was installed (a stack of electric emitters placed at the foot of the lighthouse) whereupon the old engine house was demolished.[14]  The fog signal was decommissioned in 2012.[16] In 2023 the revolving optic was removed, having been in service for over 110 years.[17] It was replaced by a fixed LED lantern, which now produces the required flash. At the same time nominal range of the light was reduced from 21 to 18 nautical miles.[18] The former keepers' cottages (arranged in two semi-detached pairs) are nowadays available to rent as holiday accommodation.[19] See alsoReferences
External links Wikimedia Commons has media related to Trevose Head Lighthouse.
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