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Lizard Lighthouse
900m east of Lizard Point, Cornwall
associated engineer
Not known
date  1751 - 22nd August 1752
era  Georgian  |  category  Lighthouse  |  reference  SW703116
ICE reference number  HEW 1369
The Lizard Lighthouse marks the most southerly point of Britain. Its pair of white towers sit atop the serpentine rock cliffs of Lizard Point in Cornwall, which are a well-known hazard to shipping.
The light's two octagonal stone towers are 19m tall and some 66m apart, with six white-washed keepers’ cottages sited between them. Each tower is 12.2m high to gallery level, 4m wide internally and has walls 1.1m thick. The west tower is now used for storage and the navigation light shines from the east tower, at a height of around 70m above mean high water level. The original twin foghorns are mounted on another building, seaward of the cottages.
The first lighthouse on this site was a tower on private land that ceased operation in 1623. Permission to build a new one was obtained in 1748, supported by Trinity House, the lighthouse authority for England and Wales. A lease was granted to Thomas Fonnerau and he built on the site of the former structure. The lease was set at £80 a year for 61 years.
The new lighthouse towers were completed in 1751 and began operating on 22nd August 1752. Fees were collected from the owners of passing ships. Burning coal in both towers provided the light. A watchman in the original small building between the towers blew a cow horn when he felt the firemen were not working hard enough on their bellows to keep the fires burning brightly!
Trinity House assumed responsibility for maintenance of the lighthouse in 1771. In 1812, structural alterations were made, including additional housing, offices and a covered passageway to the towers. The coal fires were changed to Argand oil lamps in both towers, visible for 34km over a 230° sector in fine weather. Each lamp comprised 19 burners, with individual 530mm diameter polished parabolic reflectors, housed in a plate glass lantern.
Drawings dated 1873-74 were signed by the famous lighthouse engineer Sir James Douglass. In 1878, the oil lamps were replaced by brilliant electric arc lamps, again in both towers, and a foghorn was installed. Power was provided by a steam engine driving a generator, in a purpose-built engine-house. In 1881 a second steam engine was added — one that had been on show at the Paris Exhibition and is still exhibited at the lighthouse today. The steam engines were replaced by oil-fired ones in 1895 and 1907.
In 1903, the two-light wide fixed-beam system was changed to a single flashing lamp on the east tower, which had four separate lenses at right angles sending out narrow beams of light. The lamp assembly and frame floated in a bath of mercury and completed one revolution every 12 seconds, by means of a descending weight that needed to be rewound every half hour. The arc light inside the lantern was then the most powerful in the world, with an intensity of the focused beam of 12.2 million candela, visible from the horizon whatever the height of a ship. It was said that the light was so bright that it caused several poor pilchard seasons.
The lighthouse was converted to electric power in 1924, and in 1926 the arc lamp was replaced by a 3kW filament lamp with an intensity of 5.35 million candela. In 1950 the generators were placed on standby when mains electricity was brought to the station, and the rotation of the lens assembly was now electrically driven.
The lighthouse was automated in 1998 and the keepers left on the 16th April that year. The 1903 lens assembly was retained but the power of the lamp inside was reduced to 400W Mbi with a 1kW metal halide optic. It flashes white once every 3 seconds with an intensity of 800,000 candela, and has a range of 48km. The electric fog signal is one blast every 30 seconds, from the newer foghorn mounted on the east tower.
The lighthouse now controls and monitors all the automated land stations in Cornwall and offshore stations in the Land’s End area. It is open to the paying public from March to September, with guided tours up to the lantern available.
Research: ECPK
bibliography
"Cornwall’s Lighthouse Heritage” by Michael Tarrant
Twelveheads Press, Truro, 1993
"Marconi at The Lizard — The Story of Communication Systems at Housel Bay"
by Courtney Rowe, Trevithick Society, 2000
www.trinityhouse.co.uk
reference sources   CEH South
Location

Lizard Lighthouse