1. From Historic Instances To Electrification
As an island nation, we within the UK are used to seeing lighthouses around our coasts, but have you ever stopped to think about after they were first built and the way they labored in those early days.
The aim of lighthouses is obviously to mark dangerous coastlines, rocks and reefs and to aid navigation, especially at evening or in misty situations.
The first recognized warnings made to boats of hazardous rocks and shores, had been fires, set at the sting of the water, nevertheless it was in Egypt that we first heard of precise structures being built, which used gentle to guide ships.
The Lighthouse of Alexandria
Constructed on the island of Pharos, the lighthouse was commissioned by Ptolemy in 290 B.C. It took 20 years to construct, and grew to become the tallest building in existence, except for the good Pyramid, standing at between 450 and 600 toes in height, and was recognised as one of the Seven Wonders of the World.
It is thought to have cost across the equivalent of three million dollars or £2.8 million. Its design was nothing just like the slim constructions we are accustomed to right now. It consisted of three levels, the primary being in the form of a massive field built on a 20 foot high stone platform. On prime of this was an eight sided tower, followed by a cylinder that extended to an open cupola the place the hearth burned to offer the light. On its roof was a big statue, thought to be of the sea god Poseidon. The fire’s mild was believed to have been projected right into a beam by way of a big curved mirror, in all probability made of polished bronze. It was said that ships could detect its indicators up to a hundred miles away, the sunshine from the tower by night time, and the smoke from the fireplace by day. This declare however appears a little bit excessive.
The lighthouse turned so well-known that the name “pharos” became the foundation of the word “lighthouse” in lots of languages. It stood for over 1,500 years, surviving a tsunami in 365 Advert, but earth tremors resulted in cracks forming in the construction which wanted restoration. Then, a major earthquake within the area, in the 14th century, brought on such extreme harm that the structure eventually collapsed.
Different early lighthouses
In medieval instances the Iranians apparently erected massive minaret towers in the mouth of the Persian Gulf to aid navigation. In China, the medieval mosque at Canton also had a minaret serving as a lighthouse, and in 1165 a pagoda known because the Liuhe Pagoda, was inbuilt Hangzhou and acted as a lighthouse for sailors within the Qiantang River.
One of the oldest working lighthouses in Europe is Hook Lighthouse, constructed at Hook Head in County Wexford, Ireland in thirteenth century and built in circular design. Two lighthouses, referred to as the Pharos, had been built at Dover (UK) soon after the Roman conquest of Britain. They have been constructed on two heights (the Eastern and the Western). The one on the Jap Peak still stands within the grounds of Dover Castle.
One other well-known early Roman lighthouse is the Tower of Hercules, probably in-built the primary century, on a peninsula at A Coruna in north-west Spain. It was initially identified as the “Farum Brigantium”, the Latin word farum being derived from the Greek pharos.
The sunshine was originally produced using a wooden fired system positioned on the summit platform, but the lighthouse was abandoned after the Viking Invasions of 854-56. It was restored in the 14th century when the town turned one of the kingdom’s largest ports, and by the 17th century it had been fitted with a dome formed lantern. Extra restoration was completed within the early 18th century, and in 1847, stone island jacket coat a system using Fresnel lenses (see later) was installed. It was electrified in 1926, with a beam seen for up to 32 nautical miles and is the oldest Roman lighthouse in use at present.
Some early lighthouses used wick lamps as a mild source and sometimes the beam might only journey a couple of miles. The Argand hollow wick lamp and parabolic reflector had been developed in Europe around 1781, while within the USA, whale oil was stone island jacket coat used with wicks till the Argand system was introduced around 1810,which was then later changed with Colza oil (much like rapeseed oil), lard oil and then Kerosene.
The Fresnel lens
In 1822 a Frenchman, named Augustin Fresnel, found out how to extend the sunshine depth using prisms, and the primary Fresnel lens was put in in 1822 in the Cordouan lighthouse in the mouth of the Gironde estuary. This gentle may very well be seen from 20 miles or 32 km away. By the 1860s, low-mild-loss Fresnel lenses, a lot bigger than the original ones, were in use in lighthouses around Britain and France, their use quickly extending to Italy and additional afield to Australia and America.