The Antikythera mechanism was similar in size to a mantel clock, and bits of wood found on the fragments suggest it was housed in a wooden case. Like a clock, the case would’ve had a large circular face with rotating hands. There was a knob or handle on the side, for winding the mechanism forward or backward. And as the knob turned, trains of interlocking gearwheels drove at least seven hands at various speeds. Instead of hours and minutes, the hands displayed celestial time: one hand for the Sun, one for the Moon and one for each of the five planets visible to the naked eye—Mercury, Venus, Mars, Jupiter and Saturn. A rotating black and silver ball showed the phase of the Moon. Inscriptions explained which stars rose and set on any particular date. There were also two dial systems on the back of the case, each with a pin that followed its own spiral groove, like the needle on a record player. One of these dials was a calendar. The other showed the timing of lunar and solar eclipses.
Despite a number of the mechanism's pieces being missing, further secrets continue to be revealed. For instance, an inscription tells how coloured balls were used to represent the Sun and Mars on the front face. Other mysteries continue to be debated: perhaps most interestingly, how the device was able to represent the complex movement of the planets (which from our point of view, at different times move forward and backward through the sky when viewed on a nightly basis).
For me, another prominent mystery remains - how such a complex and useful device is so unique in the record of the ancient world. Where are the prototypes, the evolutionary forebears, of the Antikythera Mechanism? Where are its copies? After all, in modern times any piece of advanced technology quickly inspires 'knock-offs'.
Was the Antikythera Mechanism a one-off work of genius, unable to be replicated? Or does it indicate that the record of the ancient world remains woefully incomplete, and that our forebears were more technologically advanced than we have thought?