Antikythera mechanism
More info
- Released
- c. 100 BC
- Type
- Analogue computing mechanism
- Found
- 1901, in a Roman wreck off Antikythera
A bronze clockwork from roughly 100 BC that computed the positions of the heavens — after which nobody on Earth built anything mechanically comparable for fourteen centuries.
Sponge divers raised the lump in 1901, and for decades it sat in a museum looking like corroded limestone with a few teeth poking out. Not until 1974 did Derek de Solla Price show that it contained at least thirty interlocking gears. X-ray tomography in 2005–2006 read the inscriptions inside without anyone having to open it.
It was not a computer in any programmable sense. It did one thing, and did it extremely well: crank the handle to dial in a date, and the faces gave the positions of the Sun and Moon, the lunar phase, the four-year cycle of the games, and eclipse predictions from the Saros cycle. A pair of eccentrically coupled gears modelled the Moon's uneven speed along its orbit.
The awkward part of the find is that nothing like it reappears until the astronomical clocks of the late Middle Ages. Either an entire workshop tradition vanished without trace, or somebody on Rhodes was working conspicuously ahead of his contemporaries.