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2009/10/27-12h29
The lighthouse at the end of the sea
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| Atop the North-West extremity of the island of Ushant towers the most powerful lighthouse in Europe. Designed in 1863 by the
engineers Rousseau and Maîtrot de Varennes, Créac'h signals landfall on the Breton coast as far out as midway across the English
Channel.
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In far-off times, the only reference for men of the sea was the land and they only rarely strayed out of sight of the
coast. However, when it was necessary to traverse closed waters like the Mediterranean, travel up and down stretches of sea
like the English Channel, pass by the Pillars of Hercules (Straits of Gibraltar), sail across the oceans as far as Thule (Iceland)
or the Cape Bojador (Mauritania) in search of new commercial routes, it was also imperative to find your way back... In this
way, on the island of Pharos, the first lighthouse was built by Sostratus of Cnidus in the 3rd century BC, to signal the entrance
to the port of Alexandria. The lighthouse probably measured a hundred metres and would have only lit up the night sky modestly,
but during the day the smoke would have been visible for tens of kilometres! Maintained with wood and oil, the light and effluvia
reached the horizon and became an amazing seamark. As such it was a point of reference for offsetting the uncertainties of
sailing by dead reckoning and the hazardous capes called into question many a time by the capricious winds and hostile seas...
In France, thanks to the Romans, several lighthouses came on stream in Marseilles, Fos and Fréjus, then from the
5th century along the North coast in Calais, Boulogne, Dieppe... However these signal stations still weren't maintained or
permanent and their visibility was still greatly reduced when the rain, wind and fog kicked in! Cordouan, "the lighthouse
of kings and the king of lighthouses" at the entrance to the Gironde, was the first to be built of stone and was completed
in 1611 after twenty seven years work... In the Iroise Sea, solely the monks from Saint Mathieu's abbey maintained a light
with olive oil and then fish oil...
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The most powerful lighthouse in Europe
At Vauban's behest, a lighthouse was built on the South-East coast of Ushant in 1695 but it was only illuminated from 1st
October to 31st March as each month it consumes forty barrels of coal, around 1,725 lbs of wood, three hundred bundles of
firewood and three pounds of tallow candle! However, it was necessary to wait until the 19th century for the network of lighthouses
around the coast of France to be developed, in particular thanks to the invention of lenticular systems and prisms by Augustin
Fresnel's (1788-1827), the awarding of control of France's signalling system to the highways department (7th March 1806) and
the creation of a Lighthouse Service Committee (1811). A massive construction programme was undertaken, which involved thirty
new lighthouses lighting up the Breton horizon between 1835 and 1861! However, it still took a little more time for a new
programme to be implemented to construct the leading lights in ports, as well as Créac'h and the first lighthouses at sea
(La Vieille, Armen, Pierres Noires, Le Four).
Started in 1859, the construction of a light seamark to the North-West
of Ushant was completed in December 1863 with the installation of Créac'h, which was electrified in 1888 and then equipped
with a flashing light (the brightness lasting less than a few tenths of a second) in 1895, a xenon bulb in 1971, then in 1995
four 2000 Watt metal iodide bulbs! This tower is 55 metres off the ground and easily identifiable by its horizontal black
and white bands. It culminates at 72 metres above sea level, which together with its 12 million candelas, provides a light
range of over 60 kilometres in clear weather! As such a vessel in the middle of the English channel can see the pencils of
light from Créac'h and Lizard (over 120 miles away), which form the virtual start and finish line of the Jules Verne Trophy...
At the foot of the lighthouse, the former engine room of the power plant has played host to the Lighthouse and Beacon Museum
since 1988.
Dominic Bourgeois
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Créac'h Lighthouse (Ushant)Position: 48° 27,61 North - 5° 07,656 West
Rythm: 2 white flashes every 10 seconds
Operational:
19th December 1863
Designer: Mr de Carcaradec
Engineers: Mr Maîtrot de Varennes and Mr Rousseau
Builder:
Mr Tritschler
Height off the ground: 54,85 metres
Height above sea level: 71,60 metres
Optics
: four two panel 2/9 lens, with a focal length of 65 cm, whose arrangement over two floors is the only one of its kind.
Illumination provided by high power 2000 W metal iodide bulbs.
Light range: 32 miles
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