Bishop Rock Lighthouse
Bishop Rock Lighthouse; once popular with holiday makers to the Isles of Scilly who went to watch the relief of the Lighthouse Keepers and now well known for featuring in the BBC One 'idents' is a lighthouse with several claims to fame.
The first attempt at building a Lighthouse on Bishop Rock took place in 1847 - the tower was designed by James Walker and was supported by 6 iron legs with an enclosed stairway up the a hollow tube-like tower in the centre.
Walker argued that this was more stable than a granite tower as the waves were able to "roll freely amongst the piles" - he was proven wrong on February 5th 1850 the lighthouse was nearing completion, ready for the installation of it's lighting apparatus, when it was destroyed and swept away by an Atlantic gale.
1859 saw the second attempt at lighting the rock - a successful granite tower.
This tower was loosely based upon the idea behind John Smeaton's Eddystone - the curved shape of the tower should deflect the waves so that they do not push the tower over.
The new tower was 35 metres tall and 10 metres in diameter at the base - it was wave-washed to make it strong and had a first order dioptric lens was installed giving a fixed white light, which was visible for 14 nautical miles. A 550lb fog bell that was bolted to the tower's gallery was torn off by a large wave, during the night of January 30th 1860 - the remains are rumoured to have been seen by divers, somewhere near the base of the current tower.
After James Walker had died in 1862, James Douglas became the Chief Engineer to Trinity House.
On a visit to the lighthouse in 1881, he made an inspection of the tower and noted cracks, extensive damage and weakness and suggested to Trinity House that the tower should be strengthened and upgraded. Trinity House agreed with Douglas' recommendations and by 1887 the lighthouse had been heightened by 12 metres, bringing its total height to 49 metres and a whole new lighthouse encased the old one, which still forms much of the tower's insides today.
At this time a new lantern and optical system were manufactured by Chance Brothers of Smethwick, near Birmingham to be installed the lighthouse - most of this apparatus still remains in use.
The new optics consisted of a two-tiered bi-form Hyper Radial setup weighing in at over 8 tonnes (one 712th of the towers weight!), with 5 panels each having an arc of 72 degrees, which makes it one of, if not the biggest optics ever installed in a lighthouse - the top half of which was only lit in fog or reduced visibility. The lower half of the optic assembly was lit every night and still operates today.
These lenses had 10 'Bulls Eyes' - when rotated, each one produced a single flash. This gave the appearance of 2 flashes every 15 seconds, visible for 24 Nautical Miles.
The upper half of this set-up was no longer needed after automation, so in 1992 the upper half was disassembled, removed and re-built at Penzance Lighthouse Depot. Since it's closure, the lens has been in storage and is currently on view to the public in a collection at a Lighthouse Display in the Falmouth Maritime Museum.
On Febuary 5th 1994, exactly 144 years after the collapse of James Walker's first lighthouse, the mighty force of the Atlantic struck the 1887 tower and destroyed the entrance doors, which were made of strong Gun-Metal.
Luckily, Trinity House were alerted to this when one of the doors was forced down the stairs in the tower by the strong waves, setting a fire alarm was set off as they went. When a helicopter was sent to the lighthouse, sheets of metal were used to cover the entrance (no longer used since the addition of the Helideck) - this remained the sollution until exact copys of the original doors were made and installed in 1996. The cost of the doors alone was £15,000 and the whole operation, including installation and transportation to the rock cost nearly £20,000
The lamp was converted to electricity in 1973 and shortly afterwards, in 1976 the Helideck was built over the top of the Lantern - this made the process of reliving keepers much easier, safer and more reliable, as relives made by seas could be delayed for many days, if not weeks.
2007 saw the discontinuation of the fog signal - a feature of all of the lighthouses dating right back to 1850 and Walker's first tower. The lighthouse can be seen very well from St. Agnes, 7 miles away and even quite well as far away as St. Mary's or Tresco on a clear day.
At night the lighthouse can be viewed from many points of many of the nearby islands, but probably the easiest to reach is just around the corner of Star Castle on the Garrison, St. Marys.