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Round Island Lighthouse
Round Island, Isles of Scilly
associated engineer
Sir James Nicholas Douglass
date  1887
era  Victorian  |  category  Lighthouse  |  reference  SV902178
On the most northerly of the Isles of Scilly stands Round Island Lighthouse, designed by James Douglass. It sits above a 40m high sheer wall of granite, which made material deliveries and construction difficult. Even today, the only access is by a flight of steps cut into the rock — unless you happen to have a helicopter.
The station was built for Trinity House, the organisation responsible for lighthouses in England and Wales. Round Island is about 4km north of the main island of St Mary's and at the opposite end of the island group to Bishop Rock, site of the better-known lighthouse, modified by Douglass in 1881-7.
The station at Round Island consists of a tapering circular stone tower topped with a large galleried lantern, and adjoining keepersí accommodation. All are painted white. The tower is 19m tall and the light 55m above Mean High Water.
The original light source was a ten-wick burner designed by Douglass. It had an initial intensity of 1,962 candela — more powerful than the eight-wick burner at Bishop Rock Lighthouse. The Round Island burner was contained in a hyperradial bi-form lens optic, 4.6m high and weighing over 8 tonnes — a twin of the optic still in use at Bishop Rock.
In 1966 the lighthouse was converted to electricity and in 1967 the optic was broken up on site — it was thought to be too difficult to preserve for posterity — and replaced by a more modern device. The present apparatus was installed when the station was automated in 1987.
The light is now a 1,000W metal halide lamp inside a 360mm revolving optic. It flashes white once every 10 seconds, with an intensity of 340,000 candela and a range of 44km. There is also a Nautophone fog signal that sounds four blasts every 60 seconds.
Research: ECPK
"Cornwall's Lighthouse Heritage" by Michael Tarrant
Twelveheads Press, Truro, 1993

Round Island Lighthouse