History mystery: Lighthouse of Alexandria

The most famous lighthouse, Pharos of Alexandria is one of the Seven Wonders of the World and is the archetype of all lighthouses. It was designed by Sostratus of Knidos, for Ptolemy I Soter an ex-general of Alexander the Great, the conqueror who founded and contributed his name to Alexandria. Alexandra also had seventeen cities named after him most of which are no longer in existence except for Alexandria in Egypt. The city needed a mechanism to guide trade ships into its harbor and Ptolemy I Soter constructed the lighthouse with this issue in mind. The lighthouse was completed during the reign of Soter’s son Ptolemy II of Egypt, who started building the lighthouse in 290 BC, which was completed 20 years later after it was conceived by Ptolemy I Soter.

It was the first lighthouse of the world which stood in the harbor of Alexandria on the island of Pharos and is believed to be more than 350 feet high. It was considered to be the tallest man made structure besides the Great Pyramid and was built on marble blocks. The stairway within the lighthouse led the keeper to the beacon chamber which contained a curved mirror used to project the light of the fire into a beam where ships could detect the beam from the tower at night or the smoke from it could be seen during daytime from a distance of around 100 miles away. As per the ancient sources contributed by Thiersch, the lighthouse was built in three stages and was built on three basic structural elements, sloping slightly inwards while the lowest structure or the base was rectangular, the midsection being octagonal and the topmost or the upper section which housed the beacon was cylindrical.

A broad spiral ramp led to the top where a fire would burn during the night. The Lighthouse of Alexandria for centuries marked the harbor using the fire at night and the sun ray’s reflection during the day. Moreover like famous monuments which are depicted on currency it was also shown on Roman coins. The Arabs admired Alexandria and its wealth when they had conquered Egypt and the Lighthouse is mentioned in their writings and travelers account. The lighthouse faced a little damage in 956 AD when an earthquake shook Alexandria and later in 1303 and 1323, two stronger earthquakes caused considerable damage to the structure.

Towards 1480 AD, an Egyptian, Mamelouk Sultan decided to fortify Alexandria’s defense by building a medieval fort on the same location where the lighthouse stood with the help of the fallen marble and stones. 
Ptolemy II and Sostrates of Knidos, the designer of the lighthouse both wanted their names to be carved on the structure and finally Ptolemy had his name carved instead. Sostrates being clever and tricky carved his name beneath, concealed it with plaster and then carved the name of Ptolemy II over it. With passage of time, the plaster got worn out and his name was revealed. The Lighthouse being solidly constructed survived many fierce sea storms and earthquakes for around 1600 years and though it did not survive till present day times, it has left an impact in many respect where the monument has been used as a model for many prototypes in Mediterranean as well as faraway places like Spain.