Water recovery

Eccentric Engineer

One canny engineer ensured his legacy was lit up like a lighthouse through the ages.

Engineers don’t always get the fame they deserve. Take poor old Maurice Koechlin. His were the real brains behind the armature that holds up the Statue of Liberty, but the credits always go to the sculptor Frederic Bartholdi, or perhaps the engineer he chose to help him, Gustave Eiffel. Eiffel of course would later repeat the trick with a certain tower that still bears his name, despite the structural design being, once again, by the diminutive Koechlin.

So the question is posed: how can those who actually build great monuments secure the recognition they deserve? How can they take their rightful place alongside those of the sponsors and politicians whose names tend to smother such constructions? Isambard Kingdom Brunel was lucky to die famous enough for the words ‘IK Brunel - Engineer, 1859’ to be added in huge steel letters on each end of the Royal Albert Bridge over the Tamar. But only after his death. Most, however, become obscure after shuffling off this mortal coil.

Except one. There is one great historical lesson for engineers everywhere on how to achieve your own slice of immortality, but you have to go back a long way to find it and it does involve a bit of cheating. Ptolemy II was an Egyptian pharaoh with a problem. His lovely - and relatively new - capital of Alexandria was on an almost totally flat coastline, making the harbour hard to locate from vessels out to sea. Not only that, those ships unwise enough to stray too close to the shore would find themselves in dangerous shoal waters, studded with reefs and sand banks where all but the most skilful might founder. Even with the harbour in sight, the most dangerous reef lay hidden across the entrance itself. Worse still, those unable to take the correct bearing might find themselves wrecked on the shores of the island called Pharos where the notorious inhabitants of the ‘Port of Pirates’ would easily pick them off.

What Ptolemy really needed then was a lighthouse. The man chosen for the job was Sostratus the Cnidian, whose previous work had included a ‘hanging garden’ in his home town of Cnidus in Caria and a clubhouse in Delphi where his fellow Cnidians could meet. For Alexandria, he proposed something altogether grander. The great lighthouse was to be constructed in granite and limestone blocks faced with white marble. Its total height would be at least 120m - about the height of a run-of-the-mill skyscraper. Erected on a solid base, it had three levels. The first was square and housed all the workers needed to fuel and operate the great light; the second was octagonal, decorated with exquisite statuary and where the people of Alexandria might come to enjoy the breathtaking views; the third was circular, crowned with an enormous reflector made of polished brass. Finally, atop this stood a huge bronze statue of Poseidon, god of the sea.

The light was designed to operate both day and night. During the day it was simple enough to just reflect the rays of the sun out to sea, but at night something more was required. For this, a circular shaft ran up the centre of the building, enclosing a spiral staircase that gave access to the higher floors. Up the middle of this could be winched the piles of resinous acacia and tamarisk wood that provided the fuel for a great bonfire whose light was reflected far out to sea each evening by the great mirror. The location for the lighthouse was obvious on the island whose name would come to stand for lighthouses everywhere - Pharos. Here it would be most conspicuous, not least to the wreckers and pirates who called the island home.

The building project took 12 years to complete and was said to have cost Ptolemy about 800 talents, (a talent being 27kg of gold). It was finally finished in the early years of the third century BC but this brought Sostratus his biggest problem. Obviously, the lighthouse, a wonder of the world, would be dedicated to the god and to Ptolemy, the divine Pharaoh who had ordered its construction. But what about him?

According to Lucian of Samosata, Sostratus knew he couldn’t compete with Ptolemy, but he also knew his lighthouse was built to last; indeed the Moorish traveller Yusuf Ibn al-Shaikh saw it still functioning in 1165 AD, some 1450 years later. So he carved his own inscription on the building: “Sostratus, son of Dexiphanes the Cnidian, dedicated this to the Saviour Gods, on behalf of all those who sail the seas.”

But he then plastered over this and in the plaster wrote a great dedication to Ptolemy, and Ptolemy alone, making the Pharaoh jolly happy. Sostratus was thankfully a patient man as he would have to wait for his fame, but he knew it would come. As the centuries passed, the plaster crumbled, consigning Ptolemy’s name to the dust and leaving in its place the name of the monument’s true builder, Sostratus the Cnidian - one engineer who was not going to be forgotten.

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