May 10, 2011

Seven Wonders of the Ancient World - Part Five

The Lighthouse of Alexandria

Ptolemy Soter commissioned the construction of the Lighthouse of Alexandria (also known as Pharos Lighthouse, so named for the island it was built on) for 800 silver talents. Architect Sostratos of Knidos started construction of it in 270 B.C. The lighthouse was not completed until after Soter’s death, when his son, Ptolemy Philadelphus came to power.

Constructed from large blocks of light-coloured stone, the tower was made up of three sections: a lower square section with a central core, a middle octagonal section, and, at the top, a circular section. A statue of Poseidon stood atop the tower during the Roman period. The Pharos' masonry blocks were interlocked, sealed together using molten lead, to withstand the pounding of the waves.

The lowest part was square and almost 200 feet high. It is believed this section had 364 rooms measuring from ten to twenty cubits square. The rooms were designed with vents and windows in order to absorb gusts of wind against the Lighthouse reducing the risk of collapse. These rooms were covered with beams of teakwood and an arch of stones, cemented and decorated. There were also a series of 72 wide ramps creating access to the top of the Lighthouse. Viewing galleries were constructed on the second and third levels of the structure where visitors could experience a view from nearly 400 feet high.

The interior of the upper two sections had a shaft with a dumbwaiter that was used to transport fuel up to the fire. Staircases allowed visitors and the keepers to climb to the beacon chamber. There, according to reports, a large curved mirror, perhaps made of polished metal, was used to project the fire's light into a beam.

The Pharos Lighthouse was fitted with every scientific improvement known to the age. The mirror could reflect the light more than 35 miles off-shore. Theories conflict on how the mirror was made, some say it was made from a highly polished metal while others believe it was made from silver-backed glass.

There are many legends and myths surrounding the mirror. Some say that the mirror was used as a weapon to concentrate the rays of the sun to set enemy ships on fire as they approached the harbour. Other myths refer to the use of a powerful telescope which was located at the top of the Lighthouse which used refracting mirrors to magnify objects.

The Lighthouse stood for 1,500 years. A happened to so many ancient buildings, earthquakes eventually brought it down. The first one, in 1303, shook up the entire area; the second one, 20 years later, did significant structural damage. By this time, the Lighthouse had fallen into disrepair. In 1480, Sultan Qaitbay used the stone and marble that had once made up the Lighthouse to build a fort on the very spot where the Lighthouse once stood.

In 1994 archaeologists found large blocks underwater that they believe to have been part of the Pharos Lighthouse. Some of these blocks were brought up and put on. There are rumours that are plans to turn this site into an archaeological park with a lighthouse museum. In a few years visitors may be able to rent scuba gear and dive in the bay among the remains of the great Pharos Lighthouse.

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