by Gary Vey
from ViewZone Website
In 1900 a sponge diver was working in the Mediterranean, just off the island of Antikythera at a depth of about 138 feet. Divers had noticed various fragments of ancient cargo scattered along the bottom of this location but it was one Elias Stadaitos who discovered the source of these artifacts.
Elias found the remains of a Roman cargo ship and for many months he returned to the site to find statues, pottery and interesting clumps of rock which often encrusted metallic objects.
In May of 1902 an archaeologist named
Valerios Stais noticed that one piece of interesting rock seemed
to have what looked like a gear wheel embedded in it and set the
piece aside for further inspection.
This was largely disputed by historians
who reminded the world that "planets" were only a vague concept of
scholars around the time of Copernicus in the sixteenth
Their experiment was very successful and
revealed additional gears which were critical in understanding how
the mechanism functioned.
Scientists from around the globe were
surprised at the miniaturization of the gears - similar to work of
fine watchmakers centuries later! It was also highly complex,
suggesting that the fundamental knowledge of mechanics was well
This view would later be worthy of
imprisonment or even death by the geocentric Roman Catholics
of later centuries.
We can now scan objects in 3-dimentions with CAT scans (Computer Assisted Tomography) and receive a higher resolution than with x-ray techniques.
[Right: A patient about to
undergo a CAT scan. Most of these improvements in imaging have been
employed in medicine, to detect cancer or other pathologies.]
He showed that the device was capable of much more than had previously been imagined.
[Above: actual 3-d
image obtained by Wright and Bromley]
On November 30, 2006, the journal Science published a new reconstruction of the mechanism based on the high resolution tomography conducted by Wright and Bromley.
Their work doubled the amount of readable characters and corrected previous translations. It was also announced that other small fragments of the device had been found and incorporated in to the new reconstruction.
The latest work confirms that the device was an astronomical computer or "array" used to predict the positions of heavenly bodies in the sky.
[Above: more complete
mechanical schematic of the device obtained by 3-d imaging.]
The device consists of 37 gears, of which 30 still survive.
On the front face there were graduations showing the solar cycle and the zodiac with pointers showing the position of the sun and moon and also indicating the lunar phase.
On the back of the device there was a dial showing the progress of the Saros cycle (a cycle of 18 years during which the sun, moon and earth return to their relative positions in space) and the Callippic cycle (a cyclical calendar of 76 years devised by Callipus in 330 BC. and perhaps still used during the time of the Antikythera Mechanism).
[Above: recent reconstruction showing the front (left) and back (right) panels
of the device and inner gears (center).]
Mike G. Edmunds and colleagues used imaging and high-resolution X-ray tomography to study fragments of the Antikythera Mechanism, a bronze mechanical analog computer thought to calculate astronomical positions.
The Greek device contains a complicated arrangement of at least 30 precision, hand-cut bronze gears housed inside a wooden case covered in inscriptions. But the device is fragmented, so its specific functions have remained controversial. The team were able to reconstruct the gear function and double the number of deciphered inscriptions on the computer's casing.
The device, they say, is technically more complex than any known device for at least a millennium afterwards.
The text is astronomical with many numbers that could be related to planetary motions, and the gears are a mechanical representation of a second century theory that explained the irregularities of the Moon's motion across the sky caused by its elliptical orbit.