Editing Longships Lighthouse (section)

===The current lighthouse===
[[File:Longships Lighthouse 5.jpg|thumb|Longships Lighthouse (2023).]]
In 1869 Trinity House began constructing a replacement tower to the designs of [[William Douglass (engineer, born 1831)|William Douglass]].<ref name=CN72>{{cite book |title= Rock lighthouses of Britain The end of an era? |last= Nicholson |first= Christopher |year=1995 |publisher= Whittles Publishing |isbn=1-870325-41-9 |pages=72–73}}</ref> The building of the present granite tower used much of the equipment that had previously been used in the construction of the [[Wolf Rock Lighthouse]];<ref name=CN72/> construction was supervised by Michael Beazeley, who had been assistant engineer to Douglass at Wolf Rock.<ref name="Nicholson" /> The new lighthouse was just over {{convert|117|ft}} tall. It was equipped with a [[Fresnel lens#Lighthouse lens sizes|first-order]] fixed [[catadioptric]] optic built by Dr [[John Hopkinson]] of [[Chance Brothers]].<ref>{{cite book |last1=Elliot |first1=George H. |title=European Light-House Systems |date=1875 |publisher=Lockwood & co. |location=London |page=184 |url=http://access.bl.uk/item/pdf/lsidyv38f8413f |access-date=10 March 2019 |archive-date=29 October 2020 |archive-url=https://web.archive.org/web/20201029210746/http://access.bl.uk/item/pdf/lsidyv38f8413f |url-status=dead }}</ref> The lens array, itself over {{convert|9|ft}} tall, was placed on a {{convert|4|ft|9|in|adj=on}} pedestal within the lantern; the light source was an eight-wick 'Douglass' oil lamp, powered by [[Rapeseed oil|colza]].<ref name="Boyle1997" />

The tower was first lit in December 1873, having cost £43,870 to build,<ref name=CN72/> and displayed a fixed white light with two red [[Sector light|sectors]] (to warn ships away from [[the Brisons]], to the north-east, and [[Runnel Stone|Rundlestone]], to the south-east).<ref name="Elliot1875">{{cite book |last1=Elliot |first1=George H. |title=European Light-House Systems |date=1875 |publisher=Lockwood & co. |location=London |pages=146–148 |url=http://access.bl.uk/item/pdf/lsidyv38f8413f |access-date=10 March 2019 |archive-date=29 October 2020 |archive-url=https://web.archive.org/web/20201029210746/http://access.bl.uk/item/pdf/lsidyv38f8413f |url-status=dead }}</ref> Initially the new lighthouse was fitted with a [[fog bell]], which sounded two strokes every fifteen seconds;<ref>{{cite book |title=The English Channel Pilot |date=1878 |publisher=Charles Wilson |location=London |page=[https://archive.org/details/englishchannelp00ltdgoog/page/n103 92] |url=https://archive.org/details/englishchannelp00ltdgoog |access-date=11 February 2020}}</ref> After the new tower was completed Wyatt's tower was dismantled and the higher pinnacles of rock on Carn Bras were removed.<ref name="Nicholson" />

In 1883 Longstone was altered to show an [[Occulting Light|occulting light]] (eclipsed for three seconds every minute). An explosive fog signal was introduced at the same time,<ref name="Gazette1883">[https://www.thegazette.co.uk/London/issue/25226/page/2315 London Gazette, Issue: 25226, Page: 2315, 1 May 1883]</ref> using [[Brocks Fireworks|Brock]] fog rockets to sound a signal twice every ten minutes. The bell was retained for use as an alternative signal, put to use if the explosive signal was not working, until 1897 when it was removed.<ref>[https://www.thegazette.co.uk/London/issue/26901/page/5734 London Gazette, Issue: 26901, Page: 5734, 19 October 1897]</ref> Even after these improvements, however, the ''S.S. Bluejacket'' was [[shipwreck|wrecked]] on rocks near the lighthouse on a clear night in 1898, nearly demolishing the lighthouse in the process. Often due to bad weather there was a delay in relieving the men and supplying stores. In January 1901 there was some concern that the men had run short of provisions due to the severe weather. It was found that there was plenty of stores and the only hardship was their lack of tobacco. They had taken to smoking coffee, hops and tea leaves instead.<ref>{{cite news|title=Driven To Smoking Tea-Leaves|work=The Cornubian and Redruth Times|issue=1962|date=25 January 1901|page=3}}</ref> The explosive signal was altered to sound twice every five minutes in 1899.<ref>[https://www.thegazette.co.uk/London/issue/27040/page/93 London Gazette, Issue: 27040, Page: 93, 6 January 1899]</ref>

[[File:Cornwall - Longships Lighthouse - post card 1904.jpg|thumb|left|A 1904 picture postcard of the lighthouse.]]
In 1904 the multi-wick lamp was replaced with a [[Thomas Matthews (engineer)|Matthews]] [[Mantle lamp|incandescent oil burner]]. A new Matthews-designed explosive fog signal apparatus was also installed on the lantern gallery at around the same time.<ref name="Boyle1997" /> In 1925 the lamp was again replaced, this time with a Hood petroleum vapour burner.

In 1967 the light was electrified and the tower modified: the 1873 optic was removed and in its place a pair of [[R A Lister and Company|Lister]] diesel generator sets were installed on the old lamp room floor (occupying the lower part of the lantern).<ref name="Boyle1997" /> Above them an additional floor was inserted to support a new (reduced height) first-order [[dioptric]] optic, with an electric lamp replacing the old [[Kerosene|paraffin]] burner.<ref>{{Cite web |last=Besley |first=Andrew |title=Principal keeper of Longships Lighthouse, off Lands End, Cornwall, in the operations room, checking the lighting equipment. |url=https://www.agefotostock.com/age/en/Stock-Images/Rights-Managed/MEV-11357450 |url-status=live |archive-url=https://web.archive.org/web/20230815191247/https://www.agefotostock.com/age/en/details-photo/principal-keeper-of-longships-lighthouse-off-lands-end-cornwall-in-the-operations-room-checking-the-lighting-equipment/MEV-11357450 |archive-date=Aug 15, 2023 |website=agefotostock}}</ref> It displayed an [[isophase light]] (one long five-second flash every ten seconds) and was visible up to {{convert|19|nmi|km}} distant. At the same time, the explosive fog signal was removed and a '[[Air horn|supertyfon]]' fog horn was installed:<ref name="Nicholson">{{cite book |last1=Nicholson |first1=Christopher |title=Rock lighthouses of Britain |date=1983 |publisher=Whittles Publishing |location=Caithness, Scotland |page=74 |edition=1995}}</ref> compressed air was provided by a pair of [[Worthington-Simpson]] compressor units to three [[Horn (acoustic)|sounders]], each placed alongside its own [[Pressure vessel|air tank]] on the lantern gallery.<ref name="Boyle1997">{{cite book |last1=Boyle |first1=Martin |title=Lighthouses of England and Wales: Longships |date=1997 |publisher=B & T Publications |location=Southampton, Hants.}}</ref>

[[File:Longships Lighthouse Fossick.jpg|thumb|right|Aerial view of the helipad on the lighthouse]]
In 1974 a helipad was constructed on top of the lantern, greatly easing access.<ref name="WoodmanWilson" />

In 1988 the lighthouse was automated:<ref name="Nicholson" /> the keepers were withdrawn, a new set of generators was installed and the fog horn was replaced by a new electric emitter.<ref name = "Renton2001">{{cite book |last1=Renton |first1=Alan |title=Lost Sounds: The Story of Coast Fog Signals |date=2001 |publisher=Whittles |location=Caithness, Scotland}}</ref> It was initially monitored by a telemetry link from the [[Lizard Lighthouse]]; since 1996 it has been monitored from Harwich.<ref name="Boyle1997" />

Starting in February 2025, a technical fault caused the fog horn to sound every 13 seconds<ref>{{cite web |title=Feb 2025 fault |url=https://www.bbc.co.uk/news/articles/cdelld75wgro |website=BBC News |access-date=3 Mar 2025}}</ref>