Wirral’s Sea Lights – Bidston and Leasowe Lighthouses – are to shine again for one night only, on Sunday 11th November 2018. The occasion is the nationwide “WW1 Beacons of Light” event, part of the “Battle’s Over” pageant which marks the centenary of signing the Armistice at the end of the First World War.
This will be the first time that the Sea Lights have been lit together in more than 110 years. Leasowe Lighthouse last shone on 5th July 1908. Bidston’s light was put out for the last time at sunrise on 9th October 1913.
British Foreign Minister Sir Edward Grey wasn’t thinking of lighthouses when he remarked, on the eve of the First World War:
“The lamps are going out all over Europe; we shall not see them lit again in our lifetime.”
It’s been more than a lifetime since the Sea Lights last shone together, so we can’t help being just a little bit excited. But our celebrations will be tempered not only by the reminder of the horrors of war, but also by nostalgia for the lost profession of lighthouse-keeping – it’s twenty years since the last lighthouse in England (North Foreland) was de-manned.
Also in this article:
- What to expect on the night
- Technical details and notice to mariners
- A very brief history of the Sea Lights
- Frequently asked questions
What to expect on the night
Neither Bidston nor Leasowe Lighthouse will be open to the public on 11th November. At Bidston, there will be a small private gathering.
The lights will be lit at 7pm and switched off around midnight.
The character of both lights will be “white, fixed” (which means they are white in colour and don’t flash). This is the same as the historical character of the lights when they were last operational.
The lights will be visible on the seaward side of the two lighthouses. Both lights are masked by the stonework of their lamp rooms, such that they will be visible for about 70 degrees either side of an imaginary line drawn from Bidston Lighthouse through Leasowe Lighthouse. To see both lights at the same time, you’ll need to be seaward of Leasowe Lighthouse.
Technical details and notice to mariners
The lamps that we’re using are ex-service lanterns that we acquired from Trinity House early last year. These are fairly modern (about 15 years old), low-powered LED affairs. Bidston will exhibit a 3-tier SABIK LED-350 (36W) lantern, and Leasowe will exhibit a smaller 3-tier SABIK LED-155 (18W) lantern. These lamps both have a very narrow vertical divergence (about 2 degrees), which means that the light is concentrated into a narrow “focal plane” that widens slowly with distance. If my sums are correct, the bright part of Bidston’s light won’t intersect with an observer at sea level closer than about 4 miles, which is out at sea. Of course the lights will appear much brighter to an elevated observer at close range, like a drone perhaps.
These lights are not as bright as the lamps that were used in the latter days of the Sea Lights. Another difference is the horizontal divergence. When Leasowe was last operational, it used an oil-burning catoptric light (i.e. a parabolic reflector) which gave a fairly narrow beam aimed at the horizon (so it wasn’t as bright off the central axis of the reflector). Bidston’s light was a first order dioptric lens with vertical condensing prisms, also oil-burning; the lens gave a focal plane, with a narrow vertical divergence, while the vertical condensing prisms concentrated the light from the focal plane into a beam centred on the Horse Channel.
Peel Ports issued the official Notice to Mariners on 30 October 2018. The text is reproduced here.
Notice to Mariners
No. 60 – 2018
PORT OF LIVERPOOL
NOTICE IS HEREBY GIVEN that as part of the nationwide WWI Beacons of Light event, the disused lighthouses at Bidston and Leasowe will be re-lit temporarily.
|Duration:||1900 to 2359 on 11 November 2018|
|Bidston LtHo||Leasowe LtHo|
|Latitude:||53° 24.066′ N||53° 24.789′ N|
|Longitude:||3° 4.461′ W||3° 7.551′ W|
|Elevation:||66m above MHWS||29m above MHWS|
|Character:||White, fixed||White, fixed|
|Range (nominal):||15nm (est.)||10nm (est.)|
|Arc of visibility:||Both lights will be visible within an arc of 140°
centred on a bearing on 291.48°(T)
Mariners are advised that the temporary re-lighting of the two lighthouses is for commemorative purposes only, and the lights exhibited must not be considered as aids to navigation.
History of the Sea Lights
The Sea Lights were originally established in 1763 to guide ships through the Horse Channel, a safe passage between the sandbanks of Hoyle Bank and Burbo Bank in Liverpool Bay, before venturing through the Rock Channel and onwards to the Port of Liverpool. When the original lower light collapsed a few years later, a new lighthouse was built to replace it, 2.3 miles further inland on Bidston Hill. To make this work, Liverpool’s Harbour Master, William Hutchinson, came up with a new method of lighthouse illumination – oil lamps equipped with parabolic reflectors. Bidston’s reflector – a massive 12 feet in diameter – was probably the largest of its kind ever deployed in an operational lighthouse. It wasn’t long before Trinity House, the Northern Lighthouse Board and the rest of the world copied Hutchinson’s invention.
The Sea Lights, at 2.3 miles apart, were the most widely separated pair of leading lights in the world. Bidston Lighthouse, 2.4 miles from the high water mark by Leasowe Lighthouse, claims the distinction of being the world’s most inland lighthouse ever.
The Sea Lights were made obsolete by changes in Liverpool Bay. When Leasowe Lighthouse was discontinued, in 1908 the Horse Channel was barely navigable. Most ships were using the new Queen’s Channel, which is still in use today.
We are grateful to:
- Bruno Peek for co-ordinating the “Battle’s Over” pageant
- Peel Ports (the Local Lighthouse Authority for Liverpool) for granting permission to exhibit temporary lights at Bidston and Leasowe Lighthouses, and for issuing the Official Notice to Mariners
- Trinity House (the Lighthouse Authority for England and Wales) for their co-operation and assistance
- The Northern Lighthouse Board for providing the equipment necessary to re-program the character of our lanterns
- The Association of Lighthouse Keepers, just because.
Frequently asked questions
Q. If I take a boat out on 11th November, will the Sea Lights guide me safely through the Horse Channel?
A. No! Please don’t do that! The channels and sandbanks of Liverpool Bay have changed a lot since the Sea Lights were last operational. If you do take a boat into Liverpool Bay on the 11th November, you should be able to see the Sea Lights from several miles distance. But for navigational purposes, you should rely on your usual GPS equipment and up-to-date sea charts. There are more than 350 shipwrecks in Liverpool Bay, and we won’t be held responsible for another, despite Wirral’s age-old tradition of wrecking and smuggling!
Q. Aren’t Bidston and Leasowe lit already?
A. No, not really. At Bidston we have a strip of colour-changing LED lights which switch on around dusk and off after midnight. The light from these is unfocussed and can’t be mistaken for an operational Aid to Navigation. There’s a similar arrangement at Leasowe.
Q. Why can’t you do this every night?
A. There are strict regulations governing lighthouses and other aids to navigation, and we don’t want to be charged with setting false lights! Only Lighthouse Authorities are allowed to operate lighthouses. Peel Ports is the Local Lighthouse Authority for Liverpool, a responsibility they inherited from the Mersey Docks and Harbour Company. Trinity House is the Lighthouse Authority for England and Wales, the Northern Lighthouse Board (NLB) is the Lighthouse Authority for Scotland and the Isle of Man, and the Commissioners of Irish Lights (CIL) are the Lighthouse Authority for Eire and Northern Island. Both the NLB and CIL defer to Trinity House on certain matters.
Q. What does “nominal range” mean?
A. Without getting too technical, the “nominal range” is a measure of the strength of the light. It’s not related to the “geographic range”, i.e. the distance from which a shipboard observer in clear weather could be expected to see the light if it was bright enough. The geographic range is determined solely by the elevation of the light above the sea. When last operational, the Sea Lights were bright enough to be seen at the full limit of their geographic range (21 nautical miles for Bidston, and 14 for Leasowe).
Q. When can I visit Bidston and Leasowe Lighthouses?
A. Bidston Lighthouse is closed until Spring next year, although private tours can still be arranged during the winter months; details of future public open days will be posted on the Bidston Lighthouse Events page. The last two open days at Leasowe Lighthouse this season are on the 4th and 18th November, both Sunday afternoons; Leasowe Lighthouse will re-open on the first Sunday in March 2019.