Around 70 BC, a large Roman Galley trading between Asia Minor and Greece, had the misfortune to be hit by a storm and sunk. Amongst its cargo were examples of Greek art, coins and what became known as the Antikyherea Mechanism.
At first sight, the Antikyherea Mechanism, looked an awful lot like a metal thingy, a lumpen metal thingy at that. In fact, it is a cross between an early calculator, an astrolabe and an ephemeris. The idea that the object was something very special developed after it was X-rayed, and it was discovered that it had gears. The number of the gears became important, one set comprised 127 gears and another 235. These numbers were very significant - if you can guess why, then go straight to the top of the class. No, OK, well, the 127 gears refer to the moon’s orbit, and the 235 gears cover 19 solar years.
A more thorough X-Ray analysis, using a specially designed X-ray machine, suggests that the original object may have comprised of 50-60 gear wheels, the largest of which would have had 222/223 gears. So it seems that the mechanism would have been able to calculate the motions of other heavenly bodies too. The large cog, for example, did not predict the movement of a planet as such, but was able to calculate an 18 year period which ties in with the lunar eclipse. Not only that, it would have been able to predict the colour that the eclipse would appear to be from the earth. A different cog is marked with an ‘H’ type glyph, which could refer to the ancient Greek word ‘Helios’, meaning ‘Sun’, which suggests that the machine also calculated solar eclipses.
One of the most remarkable things about the Antikyherea Mechanism, is that we know quite a lot about the person who made it. The marks on the cogs correspond with the Corinthian names for the months, (each Greek state used different words), so we know it was either made in Corinth itself, or a Corinthian colony such as Syracuse. We may even know who designed, or at least influenced the design, of the object - Archimedes.
Archimedes was a 3rd century mathematician and astronomer, who lived in Syracuse at the time of a conflict with Rome. Furthermore, Cicero mentions that he built a machine which could calculate eclipses and the orbit of planets.
So, why go to all this trouble to forecast celestial patterns? To many ancient peoples, the movement of the planets and phases of the moon were a vital part in determining the best time to hold religious ceremonies (a bit like the way modern Easter is calculated by the time of the full moon). Equally, the heavens would have been used to ascertain the best time to plant crops, crown a king or go to war. To the ancients, astronomy and astrology (the two were basically seen as the same thing at the time), were so vital that they were willing to invest the time and intellects of their greatest craftsmen and scientists to produce complex tools solely for astrological use.