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The Early Lighthouses Ancient lighthouses were purely a tower with a 'basket' constructed at the top, where a fire was lit. The fires needed to be maintained which was difficult as was removing the ash afterwards. By the reign of Henry VIII, when British shipping and commerce began to grow, it became necessary to take the matter of lighthouses seriously in hand, and the King granted a charter to a society which was to build and maintain light beacons at certain points on the coast.
Modern day lighthouses carry a powerful light to warn ships or aeroplanes that they are
approaching a place (usually land) dangerous or important to navigation. The light is
magnified and directed out to the horizon or up to the zenith by a series of mirrors or
prisms. Increasingly lighthouses are powered by electricity and automated rather than
staffed; the more recent models also emit radio signals.
Strong as a Rock A wiser system of construction for the lighthouse towers came into favour when Smeaton built the second Eddystone Lighthouse. It was made of massive blocks of stone, dovetailed together, the foundations being dovetailed into the rock itself, so that the lighthouse really became a continuation of the rock on which it was built. Also the shape of the tower, tapering towards the top, was based on the principle of the tree trunk, which weathers the storms so well. There are, of course, different plans and designs for dovetailing the stonework, but the principle of Smeaton is still used. The walls are made much thicker at the bottom of the lighthouse than the top, and in the Wolf Rock Lighthouse, for instance, off Land's End, which is shown here, the walls at the level of the entrance door are nearly eight feet thick, and they gradually decrease till they are only two and a quarter feet near the top. It is in the brilliance of the light that the most marvellous improvements have taken place in recent years. Oil, gas and electricity are all used, but the power of the light is enormously increased by the wonderful system of lenses through which the light is made to shine. In lighthouses which are to shine only in one direction a combination of lenses, prisms and reflecting mirrors gives a concentrated and powerful beam. There are all sorts of combinations of lenses and prisms, but the principle is more or less the same. The First Revolving Light
Up to Smeaton's day coal and wood fires had been used to give the light, but he, for the first time, used tallow candles, placing 24 in a chandelier, and the total value of the light was only 67.2 candle power. Contrast this with the present illumination of some lighthouses, which throw a beam of over 60 million candle power that can bee seen for a distance of more than 30 miles. The Lighthouses
Some people feared for the lighthouse should a really terrific storm sweep round it, but Winstanley laughed at all their fears. "I only wish," said he "that I may be in the lighthouse in circumstances that will test its strength to the utmost." On the afternoon of November 26th, 1703, he set off in dirty weather from Plymouth for the Eddystone Rock, deciding to stay there for the night. Then came the Great Storm, with its dramatic consequences. We know no more of what happened, except that when daylight dawned on the morning of November 27th, and men looked out towards the Eddystone Rock, there were no signs of a lighthouse. The Rock was bare as it used to be. Winstanley's structure, with its designer, had been swept away for ever by the Great Storm. A wiser system of construction for the lighthouse towers came into favour when Smeaton built the second Eddystone Lighthouse. It was made of massive blocks of stone, dovetailed together, the foundations being dovetailed into the rock itself, so that the lighthouse really became a continuation of the rock on which it was built.
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