Two thousand years ago, a Roman cargo ship, loaded with ancient jewellery, pottery, marble sculptures and rare glass was wrecked off the coast of Antikythera, a Southern Greek Island. It was bound for Rome, bearing looted treasures to decorate a Triumphal Parade for Julius Caesar.
In 1901, Captain Dimitrios Kontos discovered the wreck when he was with a group of sponge divers. He was assisted by the Royal Hellenic Navy to retrieve the cargo. Among the treasures was a wooden box, barely a foot in height, containing a strange mechanical device, later known as the ‘Antikythera Mechanism’. (AM). It inspired years of Archaeological, Astronomical and Mathematical Research to identify and understand its function.
An international team of Scientists decreed this device was a mechanical, crank operated, astronomical calendar and that it was the world’s first mechanical computer. It is made of recycled metal plates, which makes it environmentally friendly.
Eighty-one fragments of AM were excavated, but research was hampered because they were clumped tightly together, heavily rusted and encrusted. The British Museum made a model of AM, but it did not provide full information. Michael Wright of the Science Museum also rose to the challenge, but without a full result.
AM was a breathtaking masterpiece of mechanical engineering, a joy to Epigraphists and Mechanical Engineers alike. It was covered in inscriptions which provided a users’ manual. There were more than thirty bronze gear wheels joined up to dials and pointers. It provided much knowledge of the ancient Greek cosmos.
Cicero, in his ‘De Republica’ refers to two machines that predicted the movement of the sun and planets.
Following Research at University College London, a team has announced, this year, a successful result showing how AM worked. The results are published in ‘Springer Nature. Scientific Reports’. Article 5821. Published 2021.
They produced a new model, using previous models and are pleased with the result.
The motion of the universe is displayed on this hand powered device and the movement of the five planets known in antiquity, Mercury, Venus, Mars, Jupiter and Saturn are predicted. Also predicted are the Moon’s phases together with solar and lunar eclipses.
Adam Wojcik, a Material’s Scientist, and a spokesman for the team said,
“We believe that our reconstruction fits all the evidence that Scientists have gleaned from extant remains to date”
Readers need to be aware that two thirds of the mechanism is missing which makes it almost impossible to understand the mechanism. This means their result is truly amazing. They have made the first model that explains the mechanism and fits with the evidence.
In the course of their work, they used inscriptions on the original device for facts about the mechanism and a Mathematical method described by the ancient Greek Philosopher, Parmenides, to work out the gear arrangements in a tiny space.
Readers need to be aware that the AM assumed that the Sun and Planets revolved around the Earth and therefore their routes were more difficult to reproduce with gear wheels, than if the sun was positioned at the centre.
Micro X – ray computed tomography and polynomial texture mapping made decoding the rear of the machine possible. The front presented a huge challenge; it had an epicyclic system ( one gear above another), but space was very limited for such gears. Also tomography revealed unexpectedly complicated periods for the planets, Venus and Saturn. They wanted to include cycles for all the planets.
The team managed to create gearing that suited the epigraphic evidence (inscriptions). A ring system was used with nine outputs carried by nested tubes with arms supporting the rings. This way everything supported the evidence.
The new model has logic. The team concludes that their research included many aspects of Astronomy and brought in the Greek skill of Geometry. It calculated the ecliptic longitudes of the Moon, Sun and Plants, phases of the moon, synodic phases of the Planets. Also the heliacal risings and settings of important stars. Not forgetting, above all, the Olympiad Cycle.
AM was the first known device that mechanised predictions of scientific theories. It is a brilliant creation that combines Greek Astronomical theories with cycles of Babylonian Astronomy and Mathematics from Plato’s Academy.
Congratulations to the team at UCL on their Research and giving us understanding of the ancient Greek Cosmos. They have made us rethink our previous views on ancient Greek technological knowledge.