Antikythera is an unremarkable Greek island in many ways, 20 square kilometres of fairly arid and barren land. It does not make the top 50 Greek islands either by population or size. Like many Greek islands it is also home to many shipwrecks. One of these has utterly changed our understanding of the ancient world.
Discovery
The wreck was discovered completely by chance off Antikythera by sponge divers in 1900. Their boat took shelter off Antikythera while waiting for a favourable wind and they took the opportunity to dive there. The first diver signalled to be brought to the surface almost as soon as he hit the bottom. When he got to the surface, he told his crew mates that he had seen rotting human and equine corpses, they thought he was suffering from nitrogen poisoning and had lost his wits. The captain Dimitrios Kondos, put on the diving suit and when down, he realised what his crew mate had actually seen were statues on the sea floor. Kondos returned to the surface with the arm of a bronze statue. The weather changed and the fishermen went to their sponge fishing grounds but returned at the end of the season to Antikythera and made a number of additional dives recovering additional artefacts. Kondos reported the finds to the Greek navy, and they took responsibility for the salvage operation on the site in November 1900.
The wreck yielded numerous statues, in both Marble and Bronze, coins, large bronze spears from statues, jewellery and ceramics. It also yielded an ancient weapon known as a Dolphin, essentially a weaponised ship anchor, designed to be dropped from a height onto the hull of an attacking ship in an effort to break through the deck and the hull. In 2016 human remains were recovered from the site, giving clues to who the people on the boat were. However, the most significant historical discovery was a heavily corroded lump of bronze and wood that was largely ignored at the time of discovery or rejected as something more modern that had somehow found its way to the bottom of the sea floor at the site of the wreck.
Scientific Investigations
The items were recovered in 1900, preservation then was not as advanced as it is today so when the items were removed from the sea they were not treated resulting in corrosion and oxidation. All of the items retrieved from the wreckage were transferred to the National Museum of Archaeology in Athens for storage and analysis. The mechanism went unnoticed for two years, while museum staff worked on piecing together more obvious treasures, such as the statues. In May 1902, archaeologist Valerios Stais, found one of the pieces of rock had a gear wheel embedded in it. This discovery marked the beginning of the process of pulling back the curtain on just how advanced Greek astronomy and manufacturing was. From the outset Stais believed the object was an astronomical clock, but prevailing wisdom was that such a conclusion was impossible as that type of object was too complex to have been manufactured in that period.
Albert Rehm a German scientist was the first to propose that it was an astronomical calculator. In the 1950’s a British science historian and Yale University professor Derek J. de Solla Price became interested, he along with Greek nuclear physicist Charalampos Karakalos made X-ray and gamma-ray images of the 82 fragments revealing a level of detail that had not been suspected up to that date and also identifying previously unrecognised or hidden gears. Price published a paper on their findings in 1974. Price also produced the first working model of the mechanism, a number of working models have subsequently been produced.
Initially discovered as one block, it cracked into 3 major parts after recovery. Part of the issue was that 2,000 years underwater had turned the mechanism’s bronze into a brittle mineral called atacamite, distorting the device’s dimensions and measurements. There are 82 known fragments in total, 7 of which are mechanically key, named fragments A-G. More may exit in storage in the museum in Athens, Block F was essentially discovered by accident in this way in 2005.
What was The Antikythera Mechanism’s Purpose?
The Antikythera mechanism was a complex mechanical computer of bronze gears that reflected the Greeks (and the Babylonians) astronomical understanding, including some in built errors in their understanding in relation to Mars retrograde orbit, relative to the Earth. It was designed to accurately calculate astronomical positions of all the planets visible to the naked eye. Why did people invest so much time and effort in putting something so complex together? It is worth remembering that in the ancient world people believed that the positions of the planets had a huge significance on the likely outcome of any venture, this belief system is encapsulated in the old Roman saying, “Don’t go to war when Mars is in the sky!”
Manufacture
Its date of manufacture and what it was doing on the ship are still unknown. Best estimates put the ship’s date of manufacture to 100 BC +/- 30 years. Coins discovered in the 1970s during work by Jacques Cousteau were found to have been minted between 76 and 67 BC. The coins also suggest a link to the Greek city of Pergamon, home of the Library of Pergamum. This library was second in importance only to the Library of Alexandria at the time. Some scholars argue that inscriptions suggest a link to the Colony of Syracuse and the possibility that a certain fellow called Archimedes was potentially involved in the devices manufacture. Other disagree with this interpretation and argue that it comes from Rhodes. Rhodes was a busy trading port and centre of astronomy and mechanical engineering, home to the astronomer Hipparchus, who was active from about 140–120 BC. The mechanism uses Hipparchus’ theory for the motion of the Moon, which clearly shows he influenced its design, either directly or by educating those who designed it.
Whoever was responsible was both a genius and an artist. It is without doubt a masterpiece of craftmanship applied in exquisite detail to reflect the best scientific knowledge of the time. The methodology used in its manufacture has been lost to time. Its complexity strongly suggests that there were precursors versions that have either never been found or possibly melted down over time and the valuable metals they were made of recycled. The accuracy of the machine bearing in mind it was very likely handmade is incredible and points to sophistication in manufacturing processes that was not believed to exit at the time.
Why Risk Transport?
What something so precious was doing on the ship is another question that no one knows the definitive answer to. Some scholars argue that the cargo could have been the possessions of a very wealthy family moving house or even a collection being amassed by a very wealthy collector. Maybe. On the balance of probabilities the likelihood is that the ship’s cargo were the spoils of war or conquest. The device is so unique, complex and no doubt expensive to manufacture that it almost certainly required the resources of a state rather than an individual. Rome was expanding its hold over Greece in this period, staring from the Macedonian wars and the Battle of Corinth in 140s BC culminating in the capture of Alexandria in 30 BC. The dates on the coins found at the wreck site put the wreck date towards the end of the period of Roman expansion when they were tightening their control over the Grecian world. These clues very definitely point to the cargo being transported from somewhere that had been captured by the Romans and the key treasures from wherever had been taken over were loaded on a ship for transport to Rome as the spoils of war.
Legacy
The Antikythera mechanism is now generally accepted as the first know analogue computer. Its discovery has changed the academic view of the complexity of manufacturing in the ancient world. It is worth bearing in mind no machine of comparable complexity was produced by an human for roughly another 1400 years – or at least none that have survived to be discovered. As a machine using a large number of gears for complex concurrent calculations it is in ways a direct ancestor of the Bomba Kryptologiczna developed in 1938 by Polish cryptologist Marian Rejewski to break German Enigma-machine ciphers. The Bomba was in turn a key development on the path towards modern computers.