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the Unexplained => the Hollow Earth, Crop Circles, Strange Structures & Devices => Topic started by: Bianca on May 23, 2007, 01:55:20 pm

Title: ANTIKYTHERA Mechanism
Post by: Bianca on May 23, 2007, 01:55:20 pm


Title: Re: Antikythera Mechanism
Post by: Bianca on May 23, 2007, 01:56:36 pm

Was the Antikythera Mechanism the world’s first computer?

by John Seabrook

May 14, 2007 

The main fragment of the Mechanism, found after two thousand years under water. Courtesy Antikythera Mechanism Research Project.

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 The Antikythera Mechanism

Antikythera Mechanism; Ancient Greece; Technology; Astronomy; Archeology; Price, Derek; Wright, Michael

In October, 2005, a truck pulled up outside the National Archeological Museum in Athens, and workers began unloading an eight-ton X-ray machine that its designer, X-Tek Systems of Great Britain, had dubbed the Bladerunner. Standing just inside the National Museum’s basement was Tony Freeth, a sixty-year-old British mathematician and filmmaker, watching as workers in white T-shirts wrestled the Range Rover-size machine through the door and up the ramp into the museum. Freeth was a member of the Antikythera Mechanism Research Project—a multidisciplinary investigation into some fragments of an ancient mechanical device that were found at the turn of the last century after two thousand years in the Aegean Sea, and have long been one of the great mysteries of science.

Freeth, a tall, taciturn man with a deep, rumbling voice, had been a mathematician at Bristol University, taking a Ph.D. in set theory, a branch of mathematical logic. He had drifted away from the academy, however, and spent most of his career making films, many of them with scientific themes. The Antikythera Mechanism, which he had first heard about some five years earlier, had rekindled his undergraduate love of math and logic and problem-solving, and he had all but abandoned his film career in the course of investigating it. He was the latest in a long line of men who have made solving the mystery of the Mechanism their life’s work. Another British researcher, Michael Wright, who has studied the Mechanism for more than twenty years, was coincidentally due to arrive in Athens before the Bladerunner had finished its work. But Wright wasn’t part of the research project, and his arrival was anticipated with some trepidation.

It had been Freeth’s idea to contact X-Tek in the hope of finding a high-resolution, three-dimensional X-ray technology to see inside the fragments of the Mechanism. As it happened, the company was working on a prototype of a CAT-scan machine that would use computer tomography to make 3-D X-rays of the blades inside airplane turbines, for safety inspections. Roger Hadland, X-Tek’s owner and chief engineer, was interested in Freeth’s proposal, and he and his staff developed new technology for the project.

After the lead-lined machine was installed inside the museum, technicians spent another day attaching the peripheral equipment. At last, everything was ready. The first piece to be examined, Fragment D, was placed on the Bladerunner’s turntable. It was only about an inch and a half around—much smaller than Fragment A, the largest piece, which measures about six and a half inches across—and it looked like just a small greenish rock, or possibly a lump of coral. It was heavily corroded and calcified—the parts of the Mechanism almost indistinguishable from the petrified sea slime that surrounded them. Conservationists couldn’t clean off any more of the corroded material without damaging the artifact, and it was hoped that the latest in modern technology would reveal the ancient technology inside.

from the issuecartoon banke-mail thisThe Bladerunner began to whirr. As the turntable rotated, an electron gun fired at a tungsten target, which emitted an X-ray beam that passed through the fragment, so that an image was recorded every time the turntable moved a tenth of a degree. A complete three-hundred-and-sixty-degree rotation, resulting in three thousand images or so, required about an hour. Then the computer required another hour to assemble all the images into a 3-D representation of what the fragment looked like on the inside.

As Freeth waited impatiently for the first images to appear on the Bladerunner’s monitor, he was trying not to hope for too much, and to place his trust in the skills of the group of academics and technicians who were there with him. Among them, waiting with equal anticipation, were John Seiradakis, a professor of astronomy at the Aristotle University of Thessaloniki; Xenophon Moussas, the director of the Astrophysics Laboratory at the University of Athens; and Yanis Bitsakis, a Ph.D. student in physics. (Mike Edmunds, an astrophysicist at Cardiff University, who was the academic leader of the research project, remained in Wales.) “I was just focussed on my relief that this was happening at all, with all the delays of the past four years,” Freeth told me. “Honestly, there were times when I thought it would never happen.”

One day in the spring of 1900, a party of Greek sponge divers returning from North Africa was forced by a storm to take shelter in the lee of the small island of Antikythera, which lies between Crete and Kythera. After the storm passed, one of the divers, Elias Stadiatis, put on a weighted suit and an airtight helmet that was connected by an air hose to a compressor on the boat, and went looking for giant clams, with which to make a feast that evening.

The bottom of the sea dropped sharply, and the diver followed the underwater cliff to a shelf that was about a hundred and forty feet below the surface. On the other side of the shelf, an abyss fell away into total darkness. Looking around, Stadiatis saw the remains of an ancient shipwreck. Then he had a terrible shock. There were piles of bodies, all in pieces, covering the ledge. He grabbed one of the pieces before surfacing in order to have proof of what he had seen. It turned out to be a bronze arm.

The following autumn, the sponge divers, now working for the Greek government, returned to the site, and over the next ten months they brought up many more pieces of sculpture, both marble and bronze, from the wreck, all of which were taken to the National Museum to be cleaned and reassembled. It was the world’s first large-scale underwater archeological excavation. Evidence derived from coins, amphorae, and other items of the cargo eventually allowed researchers to fix a date for the shipwreck: around the first half of the first century B.C., a time when the glorious civilization of ancient Greece was on the wane, following the Roman conquest of the Greek cities. Coins from Pergamum, a Hellenistic city in what is now Turkey, indicated that the ship had made port nearby. The style of the amphorae strongly suggested that the ship had called at the island of Rhodes, also on the eastern edge of the Hellenistic world, and known for its wealth and its industry. Given the reputed corruption of officials in the provinces of the Roman Empire, it is possible that the ship’s cargo had been plundered from Greek temples and villas, and was on its way to adorn the houses of aristocrats in Rome. The sheer weight of the cargo probably contributed to the ship’s destruction.

“Fragmentary Knowledge” continues
Page 1

Title: Re: Antikythera Mechanism
Post by: Bianca on May 23, 2007, 02:15:35 pm

(page 2)

Most of the marble pieces were blackened and pitted from their long immersion in the salt water, but the bronze sculptures, though badly corroded, were salvageable. Although bronze sculptures were common in ancient Greece, only a tiny number have survived (the bronze was often sold as scrap, melted down, and recast, possibly as weaponry), and most of those have been recovered from shipwrecks. Among the works of art that emerged from the waters near Antikythera are the bronze portrait of a bearded philosopher, and the so-called Antikythera Youth, a larger-than-life-size naked young man: a rare specimen of a bronze masterwork, believed to be from the fourth century B.C.

Other artifacts included bronze fittings for wooden furniture, pottery, an oil lamp, and item 15087—a shoebox-size lump of bronze, which appeared to have a wooden exterior. Inside were what seemed to be fused metal pieces, but the bronze was so encrusted with barnacles and calcium that it was difficult to tell what it was. With so much early excitement focussed on the sculptures, the artifact didn’t receive much attention at first. But one day in May, 1902, a Greek archeologist named Spyridon Staïs noticed that the wooden exterior had split open, probably as a result of exposure to the air, and that the artifact inside had fallen into several pieces. Looking closely, Staïs saw some inscriptions, in ancient Greek, about two millimetres high, engraved on what looked like a bronze dial. Researchers also noticed precisely cut triangular gear teeth of different sizes. The thing looked like some sort of mechanical clock. But this was impossible, because scientifically precise gearing wasn’t believed to have been widely used until the fourteenth century—fourteen hundred years after the ship went down.

The first analyses of what became known as the Antikythera Mechanism followed two main approaches. The archeologists, led by J. N. Svoronos, of the National Museum, thought that the artifact must have been “a kind of astrolabe.” A Hellenistic invention, an astrolabe was an astronomical device that was widely known in the Islamic world by the eighth century and in Europe by the early twelfth century. Astrolabes were used to tell the time, and could also determine latitude with reference to the position of the stars; Muslim sailors often used them, in addition, to calculate prayer times and find the direction of Mecca.

However, other researchers, led by the German philologist Albert Rehm, thought that the Mechanism appeared much too complex to be an astrolabe. Rehm suggested that it might possibly be the legendary Sphere of Archimedes, which Cicero had described in the first century B.C. as a kind of mechanical planetarium, capable of reproducing the movement of the sun, the moon, and the five planets that could be seen from Earth without a telescope—Mercury, Venus, Mars, Jupiter, and Saturn. Still others, acknowledging the artifact’s complexity, thought that it must have come from a much later shipwreck, which may have settled on top of the ancient ship (even though the Mechanism had plainly been crushed under the weight of the ship’s other cargo). But, in the absence of any overwhelming evidence one way or the other, until the nineteen-fifties the astrolabe theory held sway.

from the issuecartoon banke-mail thisLooking back over the first fifty years of research on the Mechanism, one is struck by the reluctance of modern investigators to credit the ancients with technological skill. The Greeks are thought to have possessed crude wooden gears, which were used to lift heavy building materials, haul up water, and hoist anchors, but historians do not generally credit them with possessing scientifically precise gears—gears cut from metal and arranged into complex “gear trains” capable of carrying motion from one driveshaft to another. Paul Keyser, a software developer at I.B.M. and the author of “Greek Science of the Hellenistic Era,” told me recently, “Those scholars who study the history of science tend to focus on science beginning with Copernicus and Galileo and Harvey, and often go so far as to assert that no such thing existed before.” It’s almost as if we wished to reserve advanced technological accomplishment exclusively for ourselves. Our civilization, while too late to make the fundamental discoveries that the Greeks made in the sciences—Euclidean geometry, trigonometry, and the law of the lever, to name a few—has excelled at using those discoveries to make machines. These are the product and proof of our unique genius, and we’re reluctant to share our glory with previous civilizations.

In fact, there is evidence that earlier civilizations were much more technically adept than we imagine they were. As Peter James and Nick Thorpe point out in “Ancient Inventions,” published in 1994, some ancient civilizations were aware of natural electric phenomena and the invisible powers of magnetism (though neither concept was understood). The Greeks had a tradition of great inventors, beginning with Archimedes of Syracuse (c. 287-212 B.C.), who, in addition to his famous planetarium, is believed to have invented a terrible clawed device made up of large hooks, submerged in the sea, and attached by a cable to a terrestrial hoist; the device was capable of lifting the bow of a fully loaded warship into the air and smashing it down on the water—the Greeks reportedly used the weapon during the Roman siege of Syracuse around 212 B.C. Philon of Byzantium (who lived around 200 B.C.) made a spring-driven catapult. Heron of Alexandria (who lived around the first century A.D.) was the most ingenious inventor of all. He described the basic principles of steam power, and is said to have invented a steam-powered device in which escaping steam caused a sphere with two nozzles to rotate. He also made a mechanical slot machine, a water-powered organ, and machinery for temples and theatres, including automatic swinging doors. He is perhaps best remembered for his automatons—simulations of animals and men, cleverly engineered to sing, blow trumpets, and dance, among other lifelike actions.

“Fragmentary Knowledge” continues

Title: Re: Antikythera Mechanism
Post by: Bianca on May 23, 2007, 02:23:34 pm

Dept. of Archeology
Fragmentary Knowledge

by John Seabrook (page 3)

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Although a book by Heron, “Pneumatica,” detailing various of these inventions, has survived, some scholars have dismissed his descriptions as fantasy. They have pointed to the lack of evidence—no trace of any of these marvellous machines has been found. But, as other scholars have pointed out, the lack of archeological evidence isn’t really surprising. No doubt, the machines eventually broke down, and, as the know-how faded, there was no one around who could fix them, so they were sold as scrap and recycled. Very few technical drawings or writings remained, because, as Paul Keyser observes, “the texts that survive tend to be the more popular texts—i.e., those that were more often copied—and textbooks, not the research works or the advanced technical ones.” Eventually, following the dissolution of the Roman Empire, the technological knowledge possessed by the Greeks disappeared from the West completely.

But, if the Greeks did have greater technological sophistication than we think they did, why didn’t they apply it to making more useful things—time- and work-saving machines, for example—instead of elaborate singing automatons? Or is what we consider important about technology—which is, above all, that it is useful—different from what the Greeks considered worthwhile: amusement, enlightenment, delight for its own sake? According to one theory, the Greeks, because they owned slaves, had little incentive to invent labor-saving devices—indeed, they may have found the idea distasteful. Archimedes’ claws notwithstanding, there was, as Keyser notes, cultural resistance to making high-tech war machines, because “both the Greeks and the Romans valued individual bravery in war.” In any case, in the absence of any obvious practical application for Greek technology, it is easy to believe that it never existed at all.

In 1958, Derek de Solla Price, a fellow at the Institute for Advanced Study, in Princeton, went to Athens to examine the Mechanism. Price’s interests fell between traditionally defined disciplines. Born in Britain, he trained as a physicist but later switched fields and became the Avalon Professor of the History of Science at Yale; he is credited with founding Scientometrics, a method of measuring and analyzing the pursuit of science. The study of the Mechanism, which incorporates elements of archeology, astronomy, mathematics, philology, classical history, and mechanical engineering, was ideally suited to a polymath like Price, and it consumed the rest of his life.

Price believed that the Mechanism was an ancient “computer,” which could be used to calculate astronomical events in the near or distant future: the next full moon, for example. He realized that the inscriptions on the large dial were calendrical markings indicating months, days, and the signs of the zodiac, and postulated that there must have been pointers, now missing, that represented the sun and the moon and possibly the planets, and that these pointers moved around the dial, indicating the position of the heavenly bodies at different times.

Price set about proving these theories, basing his deductions on the fundamental properties of gearing. Gears work by transmitting power through rotational motion, and by realizing mathematical relationships between toothed gear wheels. The Mechanism concentrates on the latter aspect. Price seems to have assumed that the largest gear in the artifact, which is clearly visible in Fragment A, was tied to the movement of the sun—one rotation equalled one solar year. If another gear, representing the moon, was driven by the solar gear, then the ratio of wheels in this gear train must have been designed to match the Greeks’ idea of the moon’s movements. By counting the number of teeth in each gear, you could calculate the gear ratios, and, by comparing those ratios to astronomical cycles, you can figure out which gears represented which movements.

from the issuecartoon banke-mail thisHowever, because only a few of the gears appear at the surface of the Mechanism, and because many of the gear teeth are missing, Price had to develop methods for estimating total numbers from partial tooth counts. Finally, in 1971, he and a Greek radiographer, Dr. C. Karakalos, were permitted to make the first X-rays of the Mechanism, and these two-dimensional images showed almost all the remaining gear teeth. Price developed a schematic drawing of a hypothetical reconstruction of the internal workings of the Mechanism. In 1974, Price published his research in the form of a seventy-page monograph titled “Gears from the Greeks.” He had written, “Nothing like this instrument is preserved elsewhere. Nothing comparable to it is known from any ancient scientific text or literary allusion. On the contrary, from all that we know of science and technology in the Hellenistic Age we should have felt that such a device could not exist.”

Price expected his work on the Mechanism to change the history of technology. The Mechanism “requires us to completely rethink our attitudes toward ancient Greek technology,” he wrote, and later added, “It must surely rank as one of the greatest mechanical inventions of all time.” Price also pointed out that the Mechanism cannot have been the only one of its kind; no technology this sophisticated could have appeared suddenly, fully realized. Not only did the Mechanism demonstrate that our concept of ancient technology was fundamentally incomplete; it also contradicted the neo-Darwinian concept of technical progress in general as a gradual evolution toward ever greater complexity (technological history being the last refuge of the nineteenth-century belief in progress)—an idea firmly embedded in A. P. Usher’s classic 1929 study, “A History of Mechanical Inventions.” As Price writes, it is “a bit frightening to know that just before the fall of their great civilization the ancient Greeks had come so close to our age, not only in their thought, but also in their scientific technology.”

But Price’s work, though widely reviewed in scholarly journals, did not change the way the history of the ancient world is written. Otto Neugebauer’s huge “A History of Ancient Mathematical Astronomy,” which came out the year after “Gears,” relegates the Mechanism to a single footnote. Scholars and historians may have been reluctant to rewrite the history of technology to include research that had lingering doubts attached to it. Also, Price’s book was published at the height of the popularity of “Chariots of the Gods,” a 1968 book by the Swiss writer Erich von Däniken, which argued that advanced aliens had seeded the earth with technology, and Price got associated with U.F.O.s and crop circles and other kinds of fringe thinking. Finally, as Paul Keyser told me, “Classical scholarship is very literary, and focusses on texts—such as the writing of Homer, Sophocles, Virgil, or Horace, or it is old-fashioned and historical, and focusses on leaders and battles, through the texts of Herodotus and Thucydides, or it is anthropological-archeological, and focusses on population distributions and suchlike. So when an archeological discovery about ancient technology arrives, it does not fit, because it’s new, it’s scientific, and it’s not a text. Plus, there is only one such device, and unique items tend to worry scholars and scientists, who quite reasonably prefer patterns and larger collections of data.” Whatever the reason, as one scholar, Rob Rice, noted in a paper first presented in 1993, “It is neither facile nor uninstructive to remark that the Antikythera mechanism dropped and sank—twice”—once in the sea and once in scholarship.

“Fragmentary Knowledge” continues

Title: Re: Antikythera Mechanism
Post by: Bianca on May 23, 2007, 02:35:35 pm
Dept. of Archeology
Fragmentary Knowledge
by John Seabrook (page 4)

The National Museum in Athens took no special pains in displaying the lumps of bronze. Item 15087 wasn’t much to look at. When the physicist Richard Feynman visited, in 1980, there was little information explaining what the Mechanism was. In a letter to his family, later published in the book “What Do You Care What Other People Think?,” the physicist wrote that he found the museum “slightly boring because we have seen so much of that stuff before. Except for one thing: among all those art objects there was one thing so entirely different and strange that it is nearly impossible. It was recovered from the sea in 1900 and is some kind of machine with gear trains, very much like the inside of a modern wind-up alarm clock.” When Feynman asked to know more about item 15087, the curators seemed a little disappointed. One said, “Of all the things in the museum, why does he pick out that particular item, what is so special about it?”

For the Greeks, as for other ancient civilizations, astronomy was a vital and practical form of knowledge. The sun and the moon were the basis for calendars by which people marked time. The solar cycle told farmers the best times for sowing and harvesting crops, while the lunar cycle was commonly used as the basis for civic obligations. And, of course, for mariners the stars provided some means of navigating at night.

Xenophon Moussas, one of the two Greek astronomers who are part of the research project, is a compact, soft-spoken man. He grew up in Athens, and as a boy, visiting the museum, he often pondered the Mechanism; now as a professor of astrophysics, he uses it to connect with his undergraduate students, for whom ancient technology is often more compelling than ancient theory.

One evening in January, Moussas led me on a memorable walk around the archeological park in central Athens, which includes both the Greek and the Roman agoras. As a quarter moon shone in the clear night sky, illuminating the ruined temples and markets, Moussas narrated the story of how the ancients slowly learned to recognize patterns and serial events in the movements of the stars, and to use them to tell time and to predict future astronomical events. “It was a way of keeping track not of time as we think of it,” he told me, “but of the movement of the stars—a deeper time.”

For the Greeks, like the Babylonians before them, the year consisted of twelve “lunations,” or new-moon-to-new-moon cycles, each of which lasted an average of twenty-nine and a half days. The problem with a lunar calendar is that twelve lunar cycles takes about eleven days less than one solar cycle. That means that if you don’t make regular adjustments to the calendar the seasons soon slip out of synch with the months, and after eighteen years or so the summer solstice will occur in December. Finding a system that reconciled the lunar year with the solar year was the great challenge of calendar-making.

from the issuecartoon banke-mail thisMost ancient societies readjusted their calendars by adding a thirteenth, “intercalary” month every three years or so, although methods of calculating the length of these months, and when they should be added, were never precise. Babylonian astronomers hit upon an improvement. They discovered that there are two hundred and thirty-five lunar months in nineteen years. In other words, if you observe a full moon on April 4th, there will be another full moon in that same place on April 4th nineteen years later. This cycle, which eventually came to be known as the Metonic cycle, after the Greek astronomer Meton of Athens, was an extremely useful tool for keeping the lunar calendar and the solar calendar in synch. (The Metonic cycle is still used by the Christian Churches to calculate the correct day for celebrating Easter.) The Babylonians also established what would come to be known as the saros cycle, which is a way of predicting the likely occurrence of eclipses. Babylonian astronomers observed that eighteen years, eleven days, and eight hours after an eclipse a nearly identical eclipse will occur. Eclipses were believed by many ancient societies to be omens that, depending on how they were interpreted, could foretell the future of a monarch, for example, or the outcome of a military campaign.

The Greeks, in turn, discovered the Callippic cycle, which consisted of four Metonic cycles minus one day, and was an even more precise way to reconcile the cycles of the sun and the moon. But the Greeks’ real genius was to work out theories to explain these cycles. In particular, they brought the concept of geometry to Babylonian astronomy. As Alexander Jones, a professor of classics at the University of Toronto, put it to me recently, “The Greeks saw the Babylonian formulas in terms of geometry—they saw all these circles all spinning around each other in the sky. And of course this fits in perfectly with the concept of gearworks—the gears are making little orbits.” Some Greek inventor must have realized that it was possible to build a simulation of the movements in the heavens by reproducing the cycles with gears.

But who? Price called the inventor simply “some unknown ingenious mechanic.” Others have speculated that the inventor was Hipparchus, the greatest of all ancient Greek astronomers. Hipparchus, who is also believed to have invented trigonometry, lived on the island of Rhodes from about 140 to 120 B.C. He detailed a theory to explain the anomalous movements of the moon, which appears to change speed during its orbit of the Earth. Hipparchus is also thought to have founded a school on Rhodes that was maintained after his death by Posidonius, with whom Cicero studied in 79 B.C. In one of his letters, Cicero mentions a device “recently constructed by our friend Posidonius,” which sounds very like the Mechanism, and “which at each revolution reproduces the same motions of the sun, the moon, and the five planets that take place in the heavens every day and night.”

“Fragmentary Knowledge” continues

Title: Re: Antikythera Mechanism
Post by: Bianca on May 23, 2007, 02:39:46 pm
Fragmentary Knowledge
by John Seabrook (page 5)

As Moussas and I headed uphill, toward the Acropolis, he pointed out the spot where Meton’s astronomy school and solar observatory had been. On our way back down, we stopped at the famous Tower of the Winds, the now gutted shell of what was the great central clock of ancient Athens. Designed by the renowned astronomer Andronicus of Cyrrhus, it is thought to have been an elaborate water clock on the inside and a sundial on the outside. “But, in light of what we know about the Mechanism,” Moussas said, “I am beginning to wonder whether this was a much more complicated clock than we think.”

When Derek Price died, of a heart attack, in 1983, his work on the Mechanism was unfinished. Although his fundamental insights about the device were sound, he hadn’t figured out all the details, nor had he succeeded in producing a working model that was correct in all aspects.

That year, in London, a Lebanese man walked into the Science Museum, on Exhibition Road, with an ancient geared mechanism wrapped in a handkerchief in his pocket. Michael Wright, one of the curators of mechanical engineering, was summoned to examine the artifact, which was in four main fragments. The man said that he’d bought the artifact in a street market in Beirut several weeks earlier. The Science Museum eventually bought it from him, and Wright and a colleague, J. Field, showed that it was a geared sundial calendar that displayed the positions of the sun and the moon in the zodiac. Wright also built a reconstruction of the sundial. The style of lettering on the dial dated the device to the sixth century A.D., making it the second-oldest geared device ever found, after the Antikythera Mechanism.

In addition to his job as a curator, Wright helped to maintain the old clocks exhibited in the museum. Among them was a replica of the oldest clock that we have a clear account of, constructed in the early fourteenth century by Richard of Wallingford, the Abbot of St. Albans. It was a fantastic astronomical device called the Albion (“All-by-One”). Another reconstruction was of a famous planetarium and clock built by Giovanni de’ Dondi, of Padua, in the mid-fourteenth century, known as the Astrarium. Like many students of mechanical history, Wright had noted this odd upwelling of clockwork in Europe, appearing in several places at around the same time. He was familiar with the theory that many of the elements of clockwork were known to the ancients. With the decline of the West, goes this theory, technical expertise passed to the Islamic world, just as many of the Greek texts were translated into Arabic and therefore preserved from loss or destruction. In the ninth century, the Banu Musa brothers, in Baghdad, published the “Book of Ingenious Devices,” which detailed many geared mechanical contrivances, and the tenth-century philosopher and astronomer al-Biruni (973-1048) describes a Box of the Moon—a mechanical lunisolar calendar that used eight gearwheels. The more Wright looked into these old Islamic texts, the more convinced he became that the ancient Greeks’ knowledge of gearing had been kept alive in the Islamic world and reintroduced to the West, probably by Arabs in thirteenth-century Spain.

from the issuecartoon banke-mail thisIn the course of this research, Wright became intensely interested in the Antikythera Mechanism. Upon studying Price’s account closely, he realized that Price had made several fundamental errors in the gearing. “I could see right away that Price’s reconstruction doesn’t explain what we can see,” he told me. “The man who made the Mechanism made no mistakes. He went straight to what he wanted, in the simplest way possible.” Wright resolved to complete Price’s work, and to build a working model of the Mechanism.

Whereas Price worked mainly on an academic level, approaching the Mechanism from the perspective of mathematical and astronomical theory, Wright drew on his vast practical knowledge of arbors, crown wheels, and other mechanical techniques used in gear-train design. His experience in repairing old grandfather clocks, many of which also have astronomical displays that show the phases of the moon, led him to one of his key insights into the engineering of the Mechanism. He posited that there must have been a revolving ball built in the front dial that indicated the phases of the moon—one hemisphere was black, the other white, and the ball rotated as the moon waxed or waned. Wright also showed how a pin-and-slot construction could be used to model the movement of the moon.

Wright, who is fifty-eight, has a British public-school demeanor, which is generally courteous and hearty and seemingly rational. But he is prey to dark moods, wild, impolitic outbursts, and overcomplicated personal entanglements—“muddles,” he calls them. Although he told me, “I really hate confrontation, and antagonism of any kind, even competition,” he consistently finds himself in disastrous confrontations with people who should be his allies. Whereas academic researchers are used to collaboration, and to sharing resources and insights, Wright is temperamentally more like a lone inventor, working away in secrecy and solitude until he has found the solution.

He did have a collaborator once—Allan Bromley, a lecturer in computer science at the University of Sydney and an expert on Charles Babbage, the nineteenth-century British mathematician who was the first to conceive of the programmable computer. Bromley used to come to the Science Museum to study Babbage’s papers and drawings and Wright would often lunch with him. In 1990, the pair took new X-rays of the Mechanism, the first since Price’s. But Bromley brought the data back to Sydney and would allow Wright to see only small portions of the material. (According to Wright, Bromley confessed “that he had it fixed in his mind that it would be his name, preferably alone, that would be attached to the ‘solution.’ ”)


Title: Re: Antikythera Mechnism
Post by: Bianca on May 23, 2007, 02:48:52 pm

Dept. of Archeology
Fragmentary Knowledge

by John Seabrook (page 6)

Meanwhile, Wright got into a muddle with his boss at the Science Museum, an “out-and-out bully” who would allow Wright to work on the Mechanism only in his free time. (“We don’t do the ancient world,” Wright remembers another colleague saying.) This meant that while Wright’s wife would go on holiday with their children, Wright would go to the museum in Athens. (Eventually, after years of this routine, he and his wife divorced.)

By the late nineteen-nineties, Bromley was dying of cancer. Wright went to see him in Sydney, and Bromley turned much of the data over to him. Just as Wright was finally able to work up their findings for publication, however, he learned of the research project and the effort to take a new set of X-rays of the Mechanism. Instead of viewing this new investigation as a potential boon, he saw it as an improper encroachment on his own turf. “There is a long-established unwritten law concerning the study of Greek antiquities, which is that when one researcher has access to the material, any other researcher is denied access until the first has finished,” he wrote to me. “In my case, this understanding was swept aside through the machinations of the group.” So, when he arrived at the National Museum while the Bladerunner’s X-rays were in progress, he was not excited, like the others; he was “angry, tired, and depressed.”

The first images of Fragment D to appear on the Bladerunner’s monitor were stunning—“so much better than we dared to hope,” Freeth told me. “They took your breath way.” Inside the corroded rock was what looked like a geared embryo—the incipient bud of an industrial age that remained unborn for a millennium.

Then the team spotted an oddlooking inscription. Andrew Ramsey, X-Tek’s computer-tomography specialist, who was operating the viewer, zoomed around inside the 3-D representation until he found the right slice. Written on the side of the gear were the letters “M” and “E”—“ME.” Was this the maker’s mark? Or could “ME” mean “Part 45”? (“ME” is the symbol for forty-five in ancient Greek.) Freeth joked that Mike Edmunds had scratched his initials on the fragment. Others suggested that this particular piece of the Mechanism could have been recycled, and that the “ME” was left over from some earlier device.

Altogether, the team salvaged about a thousand new letters and inscriptions from the Mechanism—doubling the number available to Price. Together with earlier imaging, the new inscriptions support theories that both Price and Wright had advanced. On Fragment E, for example, the group read “235 divisions on the spiral.” “I was amazed,” Freeth said. “This completely vindicated Price’s idea of the Metonic cycle of two hundred and thirty-five lunar months on the upper back dial.” They also read words explaining that on the extremity of “the pointer stands a little golden sphere,” which probably refers to a representation of the sun on the sun pointer that went around the zodiac dial at the front of the Mechanism. Wright had proposed that the rings of the back dials were made in the form of spirals; the word eliki, meaning “spiral,” can be seen on Fragment E. On Fragment 22, the number “223” has been observed, pointing to the use of the saros dial as an eclipse indicator.

It was, as Xenophon Moussas put it to me, as if “we had discovered the user’s manual, right inside the machine.” What had been regarded mainly as an archeological artifact took on a different sort of artifactual status, as an important astronomical text. Very few copies of original astronomical texts remain from the period; most of our knowledge about ancient astronomy comes from other, later astronomers. Little of Hipparchus’ writing survives; we rely largely on Ptolemy of Alexandria, who some believe took much of Hipparchus’ work and called it his own.

Many of the inscriptions took months to read. Yanis Bitsakis, the Ph.D. student, collaborated with Freeth and the X-Tek team in rendering the X-ray data as computer images, while Agamemnon Tselikas, a leading Greek paleographer, did all the readings and most of the translations. As Bitsakis explained to me, “One of the difficulties in reading the texts was that in ancient Greek there were no spaces between the words, and there are many alternative readings. Also, in many cases the edges of the lines are missing, so we don’t know what is continuous text.” He and Tselikas would work on the readings through the night, frequently e-mailing and calling other members of the team about new discoveries. Moussas remembers this period, lasting until the spring of 2006, as “the most interesting time in my life.” For example, finding the words “sphere” and “cosmos” was extremely moving, Moussas told me: “I felt as though I were communicating with an ancient colleague, through the Mechanism.”

One day last month, I paid a visit to Michael Wright, in his book-and-clock-cluttered home, in West London. Wright was reading Xenophon, the Greek historian, in ancient Greek. He put the book down and brought out his model of the Mechanism from a cabinet underneath the stairs. In size, it is startlingly similar to a laptop computer, though a bit thicker. On the front dial, in addition to the pointers for the sun and the moon that Price posited, Wright added pointers for the planets and a separate pointer for the day of the year. On the back dial were two hundred and twenty-three divisions, marking months in the soros cycle; a similar dial above that showed months in the Metonic cycle. The gears were hidden inside a wooden casing, which had a large wooden knob on one side.

“Fragmentary Knowledge”
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Title: Re: Antikythera Mechanism
Post by: Bianca on May 23, 2007, 02:53:31 pm

(page 7)

Wright was still a little upset about what he considered the sweeping claims that the research group had made when it published its findings, in the November 30, 2006, issue of Nature. He almost stayed home from the two-day conference on the Mechanism that the group put on, in early December. In the end, he decided to go, taking his wife, Anne, whom he married in 1998, “to stop me from lifting my knee in some chap’s groin.”

We went upstairs to Wright’s workshop. It was filled with tools and pieces of metal, and the air held the pleasantly acrid scent of machine oil. Scattered across the tables and the floor were clever devices that Wright had fashioned out of gears—clocks, astrolabes, engines of various kinds. I recalled Price’s description of the maker of the Mechanism—“some unknown ingenious mechanic”—and wondered if this mysterious maker might have been a bit like Wright, with a workshop similarly cluttered with machines.

Wright took his model apart and showed me how all the gears fitted together. I noticed some writing on a rectangular metal plate in the middle of the mechanism, and Wright told me that it was made of recycled bits of brass left over from some previous incarnation.

“So you think that the letters ‘ME’—”

“Precisely,” Wright interjected. “I think they must relate to whatever that bit of metal was used for before.”

Then Wright put the machine back together and turned the hand knob that drives the solar gear. It engaged with the smaller gears, through the various gear trains, and the pointers began to spin around the dials. The day-of-the-year pointer moved forward at a regular pace, but the lunar and planetary pointers traced eccentric orbits, sometimes reversing course and going backward, just as the planets occasionally appear to do in the night sky. Meanwhile, the pointers on the back dials crept through the months in the saros and Metonic cycles; eclipses came and went. I noticed that as long as he kept turning the knob Wright himself seemed, for once, perfectly unmuddled.

Until this moment, I had, like many others, continued to puzzle over why, if the Greeks were capable of building such a technically sophisticated device, they used that capacity to construct what is essentially a toy—an intellectual amusement. But as I beheld this whirring, whirling symphony of metal, a perfect simulation of a mechanistic and logical universe, I realized that my notions of practicality were foolish and shortsighted. This machine was much more than a toy; it embodied a whole world view, and it must have been, for the ancients, wonderfully reassuring to behold. ♦

Title: Re: ANTIKYTHERA Mechanism
Post by: Bianca on May 25, 2007, 06:23:20 pm


Title: Re: ANTIKYTHERA Mechanism
Post by: Bianca on May 25, 2007, 06:25:43 pm


Title: Re: ANTIKYTHERA Mechanism
Post by: Bianca on May 26, 2007, 06:32:56 am

News Feature
Published online: 29 November 2006; | doi:10.1038/444534a
In search of lost time
The ancient Antikythera Mechanism doesn't just challenge our assumptions about technology transfer over the ages — it gives us fresh insights into history itself.
Jo Marchant

It looks like something from another world — nothing like the classical statues and vases that fill the rest of the echoing hall. Three flat pieces of what looks like green, flaky pastry are supported in perspex cradles. Within each fragment, layers of something that was once metal have been squashed together, and are now covered in calcareous accretions and various corrosions, from the whitish tin oxide to the dark bluish green of copper chloride. This thing spent 2,000 years at the bottom of the sea before making it to the National Archaeological Museum in Athens, and it shows.

But it is the details that take my breath away. Beneath the powdery deposits, tiny cramped writing is visible along with a spiral scale; there are traces of gear-wheels edged with jagged teeth. Next to the fragments an X-ray shows some of the object's internal workings. It looks just like the inside of a wristwatch.

This is the Antikythera Mechanism. These fragments contain at least 30 interlocking gear-wheels, along with copious astronomical inscriptions. Before its sojourn on the sea bed, it computed and displayed the movement of the Sun, the Moon and possibly the planets around Earth, and predicted the dates of future eclipses. It's one of the most stunning artefacts we have from classical antiquity.

No earlier geared mechanism of any sort has ever been found. Nothing close to its technological sophistication appears again for well over a millennium, when astronomical clocks appear in medieval Europe. It stands as a strange exception, stripped of context, of ancestry, of descendants.

Considering how remarkable it is, the Antikythera Mechanism has received comparatively scant attention from archaeologists or historians of science and technology, and is largely unappreciated in the wider world. A virtual reconstruction of the device, published by Mike Edmunds and his colleagues in this week's Nature (see 'Decoding the ancient Greek astronomical calculator known as the Antikythera Mechanism'), may help to change that. With the help of pioneering three-dimensional images of the fragments' innards, the authors present something close to a complete picture of how the device worked, which in turn hints at who might have been responsible for building it.

But I'm also interested in finding the answer to a more perplexing question — once the technology arose, where did it go to? The fact that such a sophisticated technology appears seemingly out of the blue is perhaps not that surprising — records and artefacts from 2,000 years ago are, after all, scarce. More surprising, to an observer from the progress-obsessed twenty-first century, is the apparent lack of a subsequent tradition based on the same technology — of ever better clockworks spreading out round the world. How can the capacity to build a machine so magnificent have passed through history with no obvious effects?
To get an idea of what the mechanism looked like before it had the misfortune to find itself on a sinking ship, I went to see Michael Wright, a curator at the Science Museum in London for more than 20 years and now retired. Stepping into Wright's workshop in Hammersmith is a little like stepping into the workshop where H. G. Wells' time machine was made. Every inch of floor, wall, shelf and bench space is covered with models of old metal gadgets and devices, from ancient Arabic astrolabes to twentieth-century trombones. Over a cup of tea he shows me his model of the Antikythera Mechanism as it might have been in its pomp. The model and the scholarship it embodies have consumed much of his life (see 'Raised from the depths').

The mechanism is contained in a squarish wooden case a little smaller than a shoebox. On the front are two metal dials (brass, although the original was bronze), one inside the other, showing the zodiac and the days of the year. Metal pointers show the positions of the Sun, the Moon and five planets visible to the naked eye. I turn the wooden knob on the side of the box and time passes before my eyes: the Moon makes a full revolution as the Sun inches just a twelfth of the way around the dial. Through a window near the centre of the dial peeks a ball painted half black and half white, spinning to show the Moon's changing phase.

On the back of the box are two spiral dials, one above the other. A pointer at the centre of each traces its way slowly around the spiral groove like a record stylus. The top dial, Wright explains, shows the Metonic cycle — 235 months fitting quite precisely into 19 years. The lower spiral, according to the research by Edmunds and his colleagues, was divided into 223, reflecting the 223-month period of the Saros cycle, which is used to predict eclipses.

 It's a popular notion that technological development is a simple progression. But history is full of surprises. 

To show me what happens inside, Wright opens the case and starts pulling out the wheels. There are 30 known gear-wheels in the Antikythera Mechanism, the biggest taking up nearly the entire width of the box, the smallest less than a centimetre across. They all have triangular teeth, anything from 15 to 223 of them, and each would have been hand cut from a single sheet of bronze. Turning the side knob engages the big gear-wheel, which goes around once for every year, carrying the date hand. The other gears drive the Moon, Sun and planets and the pointers on the Metonic and Saros spirals.

To see the model in action is to want to find out who had the ingenuity to design the original. Unfortunately, none of the copious inscriptions is a signature. But there are other clues. Coins found at the site by Jacques Cousteau in the 1970s have allowed the shipwreck to be dated sometime shortly after 85 BC. The inscriptions on the device itself suggest it might have been in use for at least 15 or 20 years before that, according to the Edmunds.
The ship was carrying a rich cargo of luxury goods, including statues and silver coins from Pergamon on the coast of Asia Minor and vases in the style of Rhodes, a rich trading port at the time. It went down in the middle of a busy shipping route from the eastern to western Aegean, and it seems a fair bet that it was heading west for Rome, which had by that time become the dominant power in the Mediterranean and had a ruling class that loved Greek art, philosophy and technology.
The Rhodian vases are telling clues, because Rhodes was the place to be for astronomy in the first and second centuries BC. Hipparchus, arguably the greatest Greek astronomer, is thought to have worked on the island from around 140 BC until his death in around 120 BC. Later the philosopher Posidonius set up an astronomy school there that continued Hipparchus' tradition; it is within this tradition that Edmunds and his colleagues think the mechanism originated. Circumstantial evidence is provided by Cicero, the first-century BC Roman lawyer and consul. Cicero studied on Rhodes and wrote later that Posidonius had made an instrument "which at each revolution reproduces the same motions of the Sun, the Moon and the five planets that take place in the heavens every day and night". The discovery of the Antikythera Mechanism makes it tempting to believe the story is true.

And Edmunds now has another reason to think the device was made by Hipparchus or his followers on Rhodes. His team's three-dimensional reconstructions of the fragments have turned up a new aspect of the mechanism that is both stunningly clever and directly linked to work by Hipparchus.

One of the wheels connected to the main drive wheel moves around once every nine years. Fixed on to it is a pair of small wheels, one of which sits almost — but not exactly — on top of the other. The bottom wheel has a pin sticking up from it, which engages with a slot in the wheel above. As the bottom wheel turns, this pin pushes the top wheel round. But because the two wheels aren't centred in the same place, the pin moves back and forth within the upper slot. As a result, the movement of the upper wheel speeds up and slows down, depending on whether the pin is a little farther in towards the centre or a little farther out towards the tips of the teeth (see illustration on 'Archaeology: High tech from Ancient Greece').

The researchers realized that the ratios of the gear-wheels involved produce a motion that closely mimics the varying motion of the Moon around Earth, as described by Hipparchus. When the Moon is close to us it seems to move faster. And the closest part of the Moon's orbit itself makes a full rotation around the Earth about every nine years. Hipparchus was the first to describe this motion mathematically, working on the idea that the Moon's orbit, although circular, was centred on a point offset from the centre of Earth that described a nine-year circle. In the Antikythera Mechanism, this theory is beautifully translated into mechanical form. "It's an unbelievably sophisticated idea," says Tony Freeth, a mathematician who worked out most of the mechanics for Edmunds' team. "I don't know how they thought of it."

"I'm very surprised to find a mechanical representation of this," adds Alexander Jones, a historian of astronomy at the University of Toronto, Canada. He says the Antikythera Mechanism has had little impact on the history of science so far. "But I think that's about to change. This was absolutely state of the art in astronomy at the time."

Wright believes that similar mechanisms modelled the motions of the five known planets, as well as of the Sun, although this part of the device has been lost. As he cranks the gears of his model to demonstrate, and the days, months and years pass, each pointer alternately lags behind and picks up speed to mimic the astronomical wanderings of the appropriate sphere.

Greek tragedy

Almost everyone who has studied the mechanism agrees it couldn't have been a one-off — it would have taken practice, perhaps over several generations, to achieve such expertise. Indeed, Cicero wrote of a similar mechanism that was said to have been built by Archimedes. That one was purportedly stolen in 212 BC by the Roman general Marcellus when Archimedes was killed in the sacking of the Sicilian city of Syracuse. The device was kept as an heirloom in Marcellus' family: as a friend of the family, Cicero may indeed have seen it.

So where are the other examples? A model of the workings of the heavens might have had value to a cultivated mind. Bronze had value for everyone. Most bronze artefacts were eventually melted down: the Athens museum has just ten major bronze statues from ancient Greece, of which nine are from shipwrecks. So in terms of the mechanism, "we're lucky we have one", points out Wright. "We only have this because it was out of reach of the scrap-metal man."

But ideas cannot be melted down, and although there are few examples, there is some evidence that techniques for modelling the cycles in the sky with geared mechanisms persisted in the eastern Mediterranean. A sixth-century AD Byzantine sundial brought to Wright at the Science Museum has four surviving gears and would probably have used at least eight to model the positions of the Sun and Moon in the sky. The rise of Islam saw much Greek work being translated into Arabic in the eighth and ninth centuries AD, and it seems quite possible that a tradition of geared mechanisms continued in the caliphate. Around AD 1000, the Persian scholar al-Biruni described a "box of the Moon" very similar to the sixth-century device. There's an Arabic-inscribed astrolabe dating from 1221–22 currently in the Museum of the History of Science in Oxford, UK, which used seven gears to model the motion of the Sun and Moon.

But to get anything close to the Antikythera Mechanism's sophistication you have to wait until the fourteenth century, when mechanical clockwork appeared all over western Europe. "You start to get a rash of clocks," says Wright. "And as soon as you get clocks, they are being used to drive astronomical displays." Early examples included the St Albans clock made by Richard Wallingford in around 1330 and a clock built by Giovanni de'Dondi a little later in Padua, Italy, both of which were huge astronomical display pieces with elaborate gearing behind the main dial to show the position of the Sun, Moon, planets and (in the case of the Padua clock) the timing of eclipses. The time-telling function seems almost incidental.

It could be argued that the similarities between the medieval technology and that of classical Greece represent separate discoveries of the same thing — a sort of convergent clockwork evolution. Wright, though, favours the idea that they are linked by an unbroken tradition: "I find it as easy to believe that this technology survived unrecorded, as to believe that it was reinvented in so similar a form." The timing of the shift to the West might well have been driven by the fall of Baghdad to the Mongols in the thirteenth century, after which much of the caliphate's knowledge spread to Europe. Shortly after that, mechanical clocks appeared in the West, although nobody knows exactly where or how. It's tempting to think that some mechanisms, or at least the ability to build them, came west at the same time. As François Charette, a historian of science at Ludwig Maximilians University in Munich, Germany, points out, "for the translation of technology, you can't rely solely on texts". Most texts leave out vital technical details, so you need skills to be transmitted directly.

But if the tradition of geared mechanisms to show astronomical phenomena really survived for well over a millennium, the level of achievement within that tradition was at best static. The clockwork of medieval Europe became more sophisticated and more widely applied fairly quickly; in the classical Mediterranean, with the same technology available, nothing remotely similar happened. Why didn't anyone do anything more useful with it in all that time? More specifically, why didn't anyone work out earlier what the gift of hindsight seems to make obvious — that clockwork would be a good thing to make clocks with?

Serafina Cuomo, a historian of science at Imperial College, London, thinks that it all depends on what you see as 'useful'. The Greeks weren't that interested in accurate timekeeping, she says. It was enough to tell the hour of the day, which the water-driven clocks of the time could already do fairly well. But they did value knowledge, power and prestige. She points out that there are various descriptions of mechanisms driven by hot air or water — and gears. But instead of developing a steam engine, say, the devices were used to demonstrate philosophical principles. The machines offered a deeper understanding of cosmic order, says David Sedley, a classicist at the University of Cambridge, UK. "There's nothing surprising about the fact that their best technology was used for demonstrating the laws of astronomy. It was deep-rooted in their culture."

Another, not mutually exclusive, theory is that devices such as the Antikythera Mechanism were signifiers of social status. Cuomo points out that demonstrating wondrous devices brought social advancement. "They were trying to impress their peers," she says. "For them, that was worth doing." And the Greek élite was not the only potential market. Rich Romans were eager for all sorts of Greek sophistication — they imported philosophers for centuries.

 I find it as easy to believe that this technology survived unrecorded, as to believe that this was reinvented in so similar a form. 

Michael Wright
Seen in this light, the idea that the Antikythera Mechanism might be expected to lead to other sorts of mechanism seems less obvious. If it already embodied the best astronomy of the time, what more was there to do with it? And status symbols do not follow any clearly defined arc of progress. What's more, the idea that machines might do work may have been quite alien to slave-owning societies such as those of Ancient Greece and Rome. "Perhaps the realization that you could use technology for labour-saving devices took a while to dawn," says Sedley.

There is also the problem of power. Water clocks are thought to have been used on occasion to drive geared mechanisms that displayed astronomical phenomena. But dripping water only provides enough pressure to drive a small number of gears, limiting any such display to a much narrower scope than that of the Antikythera Mechanism, which is assumed to have been handcranked. To make the leap to mechanical clocks, a geared mechanism needs to be powered by something other than a person; it was not until medieval Europe that clockwork driven by falling weights makes an appearance.

Invention's evolution

Bert Hall, a science historian at the University of Toronto in Canada, believes a final breakthrough towards a mechanical weight drive might have come about almost by accident, by adapting a bell-ringing device. A water clock could have driven a hammer or weight mechanism swinging between two bells as an alarm system, until someone realized that the weight mechanism would be a more regular way of driving the clock in the first place. When the new way to drive clocks was discovered, says Hall, "the [clockwork] technology came rushing out of the wings into the new tradition".

Researchers would now love further mechanisms to be unearthed in the historical record. "We hope that if we can bring this to people's attention, maybe someone poking around in their museum might find something, or at least a reference to something," says Edmunds. Early Arabic manuscripts, only a fraction of which have so far been studied, are promising to be fertile ground for such discoveries.

Charette also hopes the new Antikythera reconstruction will encourage scholars to take the device more seriously, and serve as a reminder of the messy nature of history. "It's still a popular notion among the public, and among scientists thinking about the history of their disciplines, that technological development is a simple progression," he says. "But history is full of surprises.
In the meantime, Edmunds' Antikythera team plans to keep working on the mechanism — there are further inscriptions to be deciphered and the possibility that more fragments could be found. This week the researchers are hosting a conference in Athens that they hope will yield fresh leads. A few minutes' walk from the National Archaeological Museum, Edmunds' colleagues from the University of Athens, Yanis Bitsakis and Xenophon Moussas, treat me to a dinner of aubergine and fried octopus, and explain why they would one day like to devote an entire museum to the story of the fragments.

"It's the same way that we would do things today, it's like modern technology," says Bitsakis. "That's why it fascinates people." What fascinates me is that where we see the potential of that technology to measure time accurately and make machines do work, the Greeks saw a way to demonstrate the beauty of the heavens and get closer to the gods.

Jo Marchant is Natures News Editor.

Article brought to you by: Nature

Title: Re: ANTIKYTHERA Mechanism
Post by: Bianca on May 26, 2007, 06:40:25 am


Title: Re: ANTIKYTHERA Mechanism
Post by: Bianca on May 26, 2007, 06:51:42 am


Title: Re: ANTIKYTHERA Mechanism
Post by: Bianca on August 18, 2007, 08:26:41 pm

                                    A Reconstruction of the Antikythera Mechanism

Dated to ca 80 BC

In the year 1900 the bronze remains of a mechanical device were retrieved from a shipwreck off Antikythera, near Crete.

It was not clear initially what the device was, except that it was clearly a sophisticated mechanism. X-ray analysis was subsequently used to probe the inner structure of the device, the details of the gears. Finally in 1974, a full analysis was published by Professor D. De Solla Price. While some of the original gearing was missing, there was enough to work out that the device was intended to show the motion of the Moon, Sun, and most likely the Planets through the years, when the handle was turned. A few years ago, John Gleave, an orrery maker based in the United Kingdom, decided to construct a working replica of the original mechanism.


A full scale reconstruction of the Antikythera mechanism

Height 12.25 inches

The front dial - showing the annual progress of the sun & moon through the zodiac, against the Egyptian calendar, rendered in Greek on the outer annulus.

Title: Re: ANTIKYTHERA Mechanism
Post by: Bianca on August 18, 2007, 08:32:49 pm


                                                       The back dials

The upper back dial displays a four year period and has five concentric inscribed rings, most probably each with 47 divisions giving the Metonic Cycle of 235 synodic months, which equals 19 solar years. The lower back dial gives the cycle of a single synodic month, and the subsidiary dial the Lunar year of 12 synodic months.

The original gearing was cut from bronze, and the 60 degree triangular teeth were finished using a file. In the reconstruction, the gearing is made from brass, set between perspex plates, with perspex dials in place of the original bronze, so that the mechanism is visible.

The instrument indicates that the technology of the time, of which this is the only surviving example, was by any measure sophisticated.

John Gleave can be reached at:-
Tel & Fax 01422 844837

Title: Re: ANTIKYTHERA Mechanism
Post by: Bianca on December 15, 2007, 07:32:20 pm

                                            THE ANTIKYTHERA CALCULATOR

                                              (The Antikythera Mechanism)

The Calculator of Antikythera, found into a naval wreckage of the I century B.C. in the waters in front of Antikythera in the Aegean sea, is one the most amazing archaeological discoveries of last century.

The mechanism, immediately appeared out of time, after years of study is provoking a discussion among scientists and archaeologists because of the complexity and the modernity of the scientific knowledge that the work implies; the epicyclic gearing with which has been built shows the elevated level of the scientific culture reached in that period. The design of this special gear makes to suppose that Hellenistic scientists knew the calculation of the planetary motion of the celestial bodies and that the same results could have been achieved in modern times.

The mechanism is constituted of a handle operating about 32 bronze gears into a wood box, as great as a shoes box. These gears could rotate the hands of special quadrants. Perhaps it has been made in Rhodes by the astronomer Gemino or his teacher Posidonio (135-51 B.C.).

After its recovery in 1902, for fifty years it is not understood what it was. In 1951 Derek John De Solla Price (1922-1983) started, for the first time, to study the mechanism in the details also with radiographies to the gamma rays range and, after about 20 years of searches, he understood its working as an astronomic calculator.

It had the function to reproduce the lunar phases and the movement of the Sun and the Moon among the constellations of the zodiac. Probably it could also represent the motion around the Sun of the visible planets at naked eye (Mercury, Venus, Mars, Jupiter, Saturn). It could be used both like an instrument for the navigation and for astronomic investigations. Currently it results to be the most ancient analogical calculator of the history.

The astronomic calculator in the classical literature – The Calculator of Antikythera is the only planetarium arrived to us, but the Latin literature quotes another older one, built by Archimede in the III century B.C., also presumably with gear mechanisms.

Cicero (106-43 B.C., contemporary to the sinking of the Calculator of Antikythera) reports that, after the conquest in Syracuse in the 212 B.C., the Roman consul Marcello carried in Rome a celestial globe and a planetarium built by Archimede (287-212 B.C.): De Re Publica, I, 14, and besides also 21 and 22; Tusculanae disputationes, I, 63.

This planetarium was mentioned also by Ovidio (I sec. B.C.) in the Fasti (VI, 263-283), Lattanzio (IV sec. A.D.) in the Divinae institutiones (II, 5, 18) and in a Claudiano epigram (IV sec. A.D.) entitled In Archimedis Sphaeram. Particularly, Claudiano adds that the instrument was contained in a starry sphere of glass. Unfortunately any description detailed of the mechanisms that animated the planetarium has been saved as the work of Archimede On the construction of the Sphere, in which he described the principles adopted in the construction, has gone lost. This literary topics, however, show that the construction of these mechanisms was very diffused for centuries.

Title: Re: ANTIKYTHERA Mechanism
Post by: Bianca on December 15, 2007, 07:34:09 pm

Antikythera calculator advances modern science – The heliocentric planetary system, proposed in modern times by Copernico in 1543 (De revolutionibus orbium coelestium), has been anticipated in the ancient times from Aristarco of Syme (310 ca. - 230 B.C.).

The studies of the last one however, were opposed for many following centuries, allowing the assertion of the Aristotle (384 - 322 B.C.) geocentric theory and of Claudio Tolomeo (100 ca. - 170 ca. A.C.), that, this last brings it in his Almagesto. Aristarco was supported only by few scientists, some contemporaries of him like Archimede in Syracuse (287 - 212 B.C.), that quotes the Aristarco heliocentric theory in his book the Arenario.

The most of the Aristarco writings have gone lost, and it is not possible to know what are the elements adopted by him to support its theory.

The knowledge of the planetary motion, necessary for the design of the epicyclic gearing present in the Calculator of Antikythera could have been one of the reasons induced by Aristarco and a lean number of Hellenistic scientists supporting the heliocentric theory.

Here the mathematical model and the analytical development for brevity are not included, but they are broadly shown in my book. In the following chart are brought, comparatively, the results of the calculation:

Title: Re: ANTIKYTHERA Mechanism
Post by: Bianca on December 15, 2007, 07:35:31 pm



Cinematic calculation based on the acquaintances of the Greek period Calculated with Newton law Measured Cinematic calculation based on the acquaintances of the Greek period Calculated with Newton law

of the Moon around Earth 1.006 0.988 1.011 0.0182*1022 0.0176*1022

of the Earth around Sun 29.782 29.786 29.790 3.544*1022 3.545*1022

Title: Re: ANTIKYTHERA Mechanism
Post by: Bianca on December 15, 2007, 07:40:43 pm

Consequently it is supposed that some sublime minds of the ancient times, with the knowledge of the equations of the epicyclic gearings that the construction of the Calculator of Antikythera implies, were able also to calculate the distance of the Earth from the Sun and accordingly the speed of the Earth and the Moon and their strength of gravity, the same results reached applying the Newton law achieving.

In such case, certainly they have also anticipated of 19 centuries the results of the law of the universal gravitation formulated by Isaac Newton in 1687 in his publication Philosophiae Naturalis Principia Mathematica.

Title: Re: ANTIKYTHERA Mechanism
Post by: Bianca on December 15, 2007, 07:46:48 pm

Besides, the mathematical model of the epicyclic gearings used for the construction of the Calculator of Antikythera, presents many kinematics analogies with the "Theory of the vortexes" used by modern and contemporary scientists to simulate the formation of the solar system.

The model of the universe to "vortexes" has been hypothesized in modern epoch by Cartesio (Principia Philosophiae Naturalis, 1644), then taken back, on new bases, by Immanuel Kant (Universal Natural History and Theory of Heaven - Allgemeine Naturgeschichte und Theorie des Himmels, 1755) and subsequently re-elaborated by Pierre-Simon de Laplace (Exposure of the system of the world, 1796; Mécanique céleste, 1799-1825). The theory of Kant, will be then acquired by the History of the Science like nebular hypothesis of Kant-Laplace.

The model to "vortexes" on the origin of the universe and of the solar system was proposed also recently (1944) by the German Carl Friedrich von Weizsäcker (1912-2007). The study has then been enriched and completed by the Dutch Gerard Pieter Kuiper (1905-1973).

The genial intuitions of the scientists of seventeenth and eighteenth centuries were confirmed by the discoveries made in recent years with the spacial telescope Hubble, put in circular orbit around the Earth by the NASA in 1999.

Therefore, like more broadly shown in my book, the proof of the use of epicyclic model in the construction of the Calculator of Antikythera and the kinematics analogies of the model tend to hypothesize that the ideas of the modern and contemporary scientists on the origin of the universe must be backdated of many centuries.

In conclusion, the discovery of the Calculator of Antikythera makes to presume that the ancient individualized two principal ideas:

The heliocentric nature opposite the geocentric one of the solar system.

The formation of the solar system based on the "Theory of the vortexes".

Title: Re: ANTIKYTHERA Mechanism
Post by: Bianca on March 26, 2008, 11:15:40 am


The small island of Antikythera
in the Aegean Sea

Title: Re: ANTIKYTHERA Mechanism
Post by: Bianca on March 26, 2008, 11:22:51 am

                                  T H E   A N T I K Y T H E R A   M E C H A N I S M

The Antikythera Mechanism was found by divers in 1901, and many died while performing the search.  The device is over 2,000 years old.

Many scientists originally thought the Antikythera Mechanism was a piece of navigational equipment.  Little did they know it would be one of the most important scientific measuring devices ever discovered.

One of the oldest known astronomical calculating devices is called the Antikythera Mechanism.  It was discovered somewhere between Greece and the Island of Crete.

The diving crew who discovered the Antikythera Mechanism originally set out to look for sea sponges.  When they discovered the sunken ship containing the device, they believed they had found sunken treasure.

The Antikythera Mechanism was housed in a wooden box.  Inside the box were many detailed gears made of bronze, and scientists originally used x-rays to look inside.

The National Bank of Greece has created the Antikythera Mechanism Research Project, a group of scientists and historians who have dedicated themselves to researching this very important discovery.

Many scientists consider the Antikythera Mechanism to be one of the most complex scientific objects ever to be preserved.  It is a key to our modern civilization.

So much research has been done on the Antikythera Mechanism that many people have recreated what it might have looked like when it was working in its original state before it sank underwater.

The Antikythera Mechanism has given many people including philosophers, astronomers, historians, and other scientists a great insight on the history of mankind and of science.

Many people have tried to recreate the Antikythera Mechanism to get a better understanding of how it worked, and to see just how complex the machine really was.  It is also a good educational tool.

The exact year that the Antikythera Mechanism is not known for sure, but many speculate it was created somewhere around the year 80-82 BC.

Aside from it being a scientific measuring device, many people consider the Antikythera Mechanism to be the world’s oldest computer.  The device is the stuff of legend, and some even say it came from aliens.

The Antikythera Mechanism contains about 30 or so gears, and within the last 50 years scientists have really begun to delve into its functions and how it may have been used many years ago.

Many feel that the Antikythera Mechanism really showed us how sophisticated and ahead of their time the Greeks were, particularly before the takeover from the Roman Empire. 

The Antikythera Mechanism is one of the first pieces of evidence to show that many people actually believed that all planets rotated around the sun, disproving the previous thoughts of thinkers like Aristotle.

The intricate way in which the Antikythera Mechanism works was so startling to many scientists, that they often dismissed the device’s dating, doubting it could be as old as it really was.

Some scientists claim they have found an ancient inscription on the inside of the Antikythera Mechanism that could help to unlock the mystery of its origins.

After many years of detailed research, the Antikythera Mechanism is now on display for millions of yearly visitors at the National Museum located in Athens, Greece.

Many famous scholars, scientists, and professors have written papers and performed lectures about the Antikythera Mechanism, giving many people different views on the ancient device.

There are many theories about who actually built the Antikythera Mechanism, and the most popular is that it was built by Posidonius, a historian who studied how the sun and moon rotated and moved.

When the Antikythera Mechanism was originally found, its wooden casing dried from the ocean water and cracked, leaving it in four separate parts, and exposing the more detailed innards to many stunned people.

Currently work is still underway to completely decipher the inscriptions found on the inside of the Antikythera Mechanism.  The final interpretation is to be released to the public in the near future.

The complexity of the gears found within the Antikythera Mechanism baffled scientists, since this type of “technology” was not though to have been in existence until around 1575.

Many feel that the Antikythera Mechanism helps to explain how such wonderful phenomena as the ancient pyramids, the Greek Colisseum, and the Parthenon were built with such exquisite detail.

Many claim that the Antikythera Mechanism is the actual first analog computer that uses dials, gears, astronomy theory, and intricate handiwork combined to make one of mankind’s oldest and most significant machines.
© 2006

Title: Re: ANTIKYTHERA Mechanism
Post by: Bianca on March 26, 2008, 11:31:10 am

                                  The Antikythera Mechanism's Implications

   It is neither facile nor uninstructive to remark that the
Antikythera mechanism dropped and sank--twice.  The first time was
around 76 B.C., when the intricate astronomical computer was lost with
the rest of a treasure-ship's cargo.  The second time came after Derek
De Solla Price analyzed and published its construction and nature
decades after its recovery.  Since his Gears from the Greeks in 1975,
little attention has been paid to our most exciting relic of advanced
ancient technology.  It is the purpose of this paper to take Price's
conclusions, and to use that information in furthering our
understanding of the civilization that created it.

   From the fragments of the inscriptions and the position of the
gears, Price deduced that the device was linked closely to Geminus of
Rhodes, and had been built circa 87 B.C.  Besides the inscriptions'
near-identity to Geminus's surviving book, distinctive Rhodian amphorae
from the wreck supported Price's deduction.  Rhodes was a center for
astronomical thought, where Poseidonius determined the nature of the
tides and built a much more complicated astronomical computer than the
one recovered (Cic. Nat de. 2.34-35).

   Price drew his conclusions despite the widespread belief that
continues to maintain that Rhodes in 1st Century was a fading ghost of
past glory, crippled economically by the competition of the free port
of Delos.  Scholars before and after Price ignored and continue to
ignore Rhodes' enduring reputation in antiquity as a center for
intricate military and naval technology (Dio Chrys. 31.104).  With it,
the last of the Greek democracies successfully warded off even Roman
domination until 43 B.C. (Strabo 14.653, Polyb. 21.7.1-4)

   The proof the mechanism offers of Rhodes' enduring technological
expertise and economic vitality poses a question the device also helps
to answer:  Why was such an expensive and intricate device constructed?
Even in its supposed "glory days" Rhodes was chiefly famous for the
 abilities of its seafarers--and therein lies the answer.

     Very little indeed, is known about ancient celestial navigation,
besides indisputable proof that it did, in fact, occur (Homer, Od.
5.233- 40, Libanius, Progymnasmata, Sententiae 1.13).   It is worth
noting, however, that the man who invented trigonometry and first
scientifically catalogued the stars' positions was Hipparchus of
Rhodes; that in more than one ancient system of latitude and longitude
the meridians crossed at Rhodes (Dicearchos Fr. 33, Strabo 2.1.1, 5.7,
12.5, 31) and that Poseidonius's travels and mechanisms found support
at the same place where Geminus did his writings--and inspired or
built the Antikythera mechanism.

     Besides such tantalizing synchronicities, the existence of the
Antikythera mechanism also should prompt fundamental change in the
way the ancient sources are read.  When Cicero, Ovid (Fast.
6.263-283), Plutarch and others speak of intricate devices and their
use--such as an intricately- geared "machine gun" catapult, supposed
to have been built on Rhodes (Philon. Bel. 73)--the Antikythera
device's very existence should prompt us to something besides
skepticism.  When all the implications of Price's discovery are
understood and acted upon, modern scholarship shall truly be said to
have understood the Antikythera technology.

Text of the 1993 APA Abstract

Rob S. Rice

Title: Re: ANTIKYTHERA Mechanism
Post by: Bianca on March 26, 2008, 11:36:19 am

                                                     Crusty Old Computer:

                        New Imaging Techniques Reveal Construction Of Ancient Marvel

Peter Weiss

Scientists say that they have figured out the arrangement and functions of nearly all the parts of a mysterious mechanical gadget that was discovered a century ago in a 2,000-year-old shipwreck.


THEN AND NOW. Artist's rendering of the proposed internal machinery of an ancient astronomical computer (left) includes hands on upper- and lower-gear trains that rotated to track long-term astronomical cycles. Superimposed on fragments of the computer (right) is a reconstruction of a spiral dial for predicting solar and lunar eclipses.
Copyright of the Antikythera Mechanism Research Project

Since it was found, the shoe-box-size device known as the Antikythera mechanism has amazed historians and other scholars with its advanced technology. The precision assembly contains 30 bronze gears with as many as 224 presumably hand-cut teeth.

Students of the mechanism, who have long known that it served as an astronomical computer, have deemed it to be at least 1,000 years more advanced than any other known mechanical device of its era. The remains of the apparatus consist of more than 80 congealed fragments of disintegrating metal adorned with cryptic inscriptions and encrusted with corrosion.

To make sense of that shattered structure, astronomer Michael G. Edmunds of Cardiff University in Wales and his colleagues have now applied two advanced imaging techniques to the shards. One is X-ray computer tomography, which records views of an object like those produced by a medical CT scanner. A high-power X-ray source penetrated the dense relic with a beam narrow enough to reveal fine details, says Andrew Ramsey, a tomography specialist with X-Tek Systems in Tring, England.

"The computer tomography images of the mechanism have literally opened the device up to us to see how it worked," comments ancient-astronomy scholar John M. Steele of the University of Durham in England.

The researchers also applied a novel computer-enhanced, optical-imaging technique for examining surface features.

Indeed, in the Nov. 30 Nature, the team of British, Greek, and American researchers reports that its fresh look at the mechanism has uncovered clear evidence of a previously suspected function: computing lunar and solar eclipses. The new images also doubled the number of inscriptions that could be read on the device's parts. The inscriptions indicated specific functions, not all of which had been known.

Furthermore, the work revealed a previously unrecognized lunar-motion feature, says filmmaker and mathematician Tony Freeth of Images First, a leader of the study.

The researchers used their new data to come up with a revised configuration for the machine's clockwork that uses 29 of the 30 known gears plus five hypothetical gears, four of which had been proposed previously by other researchers.

The new work is "an important advance," comments Michael T. Wright, an Antikythera-mechanism scholar and a retired curator of London's Science Museum.

In the issue of Nature containing the report, François Charette of Ludwig Maximilians University in Munich calls the model "highly seductive and convincing in all of its details."

Among such details is a proposed spiral dial at the lower-back section of the device. Around this dial, the motion of a hand indicates the solar and lunar eclipses during a period of 18 years. Wright adds that the Antikythera mechanism probably also employed long-lost ways to show the motions of planets.



Title: Re: ANTIKYTHERA Mechanism
Post by: Qoais on July 31, 2008, 09:18:35 pm
Latest developments for the Antikythera Mechanism

Title: Re: ANTIKYTHERA Mechanism
Post by: Bianca on August 05, 2008, 06:33:44 am

                             Ancient world's "supercomputer" calculated Olympic Games

by Richard Ingham
Wed Jul 30, 2008
PARIS (AFP) - A clockwork machine hailed as the supercomputer of the ancient world provided a calendar for the Olympic Games and may have had a link with Archimedes, one of the greatest names
in science, investigators believe.
The 2,100-year-old device has bemused and bedazzled experts ever since its corroded and calcified bronze wheels and dials were recovered from a Roman shipwreck by Greek sponge divers in 1901.

For decades, they speculated that the machine, called the Antikythera Mechanism, was an astronomical calendar, although how it worked was unclear.

In 2006, experts using X-ray computed tomography confirmed the theory by getting a 3D view of its 29 surviving gears and used high-resolution imaging to get a close up of tiny letters engraved on the surface.

They figured it was able to estimate a 365-day calendar with the leap day ingeniously included; the 19-year Metonic calendar devised by the Babylonians; and a predictor of eclipses over a 223-month cycle, including a complex motion that became notorious as the "First Anomaly" of the Moon.

In a new study, published on Thursday in the British weekly journal Nature, the sleuths say they have now discovered that one of the dials recorded the dates of the ancient Olympics, possibly to provide a benchmark for the passage of time.

"We were astonished, honestly," said Tony Freeth, a member of the Antikythera Mechanism Research Project, gathering experts at the universities of Cardiff in Wales and of Athens and Salonika in Greece, as well as the National Archaeological Museum in Athens.

"The Olympiad cycle was a very simple, four-year cycle and you don't need a sophisticated instrument like this to calculate it. It took us by huge surprise when we saw this.

"But the Games were of such cultural and social importance that it's not unnatural to have it in the Mechanism."

The gadget was so cleverly engineered that it could fit into a small box about the size of an encyclopaedia, enabling it to be transported.

What was it used for?

Maybe it helped the rich and powerful predict times for marriage or birth or for waging war or agreeing to peace, speculates Freeth, emphasising though that no evidence has ever emerged to back such ideas.

Hi-tech imaging of the Mechanism was carried out by an eight-tonne leviathan known as BladeRunner, as its usual job was to investigator jet turbine blades to see if they carry any microscopic cracks. It was transported to Athens for the operation, as the delicate relics are housed at the National Archaeological Museum.

"BladeRunner" found another novelty -- that the dial for the Metonic calendar has names for the Corinthian family of months.

Corinth, in central Greece, established colonies in northwestern Greece, Corfu and Sicily, where Archimedes was established.

Archimedes, whose list of exploits included an explanation for the lever, the displacement of water and
a screw pump that bears his name today, died there in 212 BC.

The Mechanism was "almost certainly made many decades" after his death, said Alexander Jones, a professor at the Institute for the Study of the Ancient World in New York.

If it came from Syracuse, the dial could have been made by the school of scientists and instrument-makers he inspired.

Instead of one Olympics as there is today, the ancient Olympiads, called the Panhellenic Games, comprised four games spread over four years.

The events comprised the Pythian Games, held every four years at Delphi in honour of the god Apollo; the Isthmian Games, held every two years in Corinth in honour of Poseidon; the Nemean Games, also held every two years, in Nemea in honour of Zeus; and the most important, the Olympic Games, held every four years in Elis, also in honour of Zeus.

Drawing competitors from across the Greek empire, which stretched from Sicily to Asia Minor, the Games were so important that they became the basis for Greek chronology, becoming the term for a four-year period -- historians noted "the third year of the eighth Olympiad" and so on.

The first Olympiad, or four-year period, dated back to 776 BC, although the Games are believed to have a far longer history.

The last Games of the ancient world were recorded in 393 AD, but were outlawed by the Roman Empire as pagan. The tradition of counting in Olympiads persisted into the next century, however.

Title: Re: ANTIKYTHERA Mechanism
Post by: Bianca on August 05, 2008, 09:40:37 pm

The front face of a model replica of the ancient
astronomical calculator is seen at the National
Archaeological Museum of Athens.

                     Astronomical calculator kept track of ancient Olympics, study finds

The inclusion of the Olympic data on the 2,100-year-old Antikythera mechanism provides evidence that

for its scientific sophistication, the device also was put to practical use, researchers say.

By Thomas H. Maugh II,
Los Angeles Times Staff Writer
July 31, 2008

A 2,100-year-old bronze and iron computer that predicted eclipses and other astronomical events also showed the cycle of the Greek Olympics and the related games that led up to it, researchers reported today.

The research team also has been able to decipher all the month names from the heavily corroded fragments of the so-called Antikythera mechanism, providing the first concrete evidence that an astronomical scheme devised by the Greek astronomer Geminos was put to practical use.

 Simply complexTeasing out the month names was "a really spectacular achievement," said science historian Francois Charette of Ludwig Maximilians University in Munich, Germany, who was not involved in the research.

Historians "had until now doubted that this scheme had actually been used in civil life, but the evidence from the Antikythera mechanism now proves them wrong," he said.

The inclusion of the data about the Olympic Games on what is now called the Olympiad Dial of the clock-like mechanism was a surprise to the researchers because the dates of the ancient Olympics, held every fourth summer from 776 BC to AD 393, would have been well known to the populace, just as the time of the modern Olympics is now.

"The inclusion of the Olympiad Dial says more about the cultural importance of the Games than about their advanced technology," said Tony Freeth of Images First Ltd. in London, who was a member of the research team that reported the results in the journal Nature.

The Antikythera mechanism, so named because it was found in 1901 in a Roman shipwreck off the Greek island of Antikythera, is thought to have been made about 100 BC.

Its purpose was a mystery for more than 100 years, but in 2006, researchers used a massive X-ray tomography machine, similar to that used to perform CT scans on humans, to examine the heavily encrusted fragments.

They concluded that the device originally contained 37 gears that formed an astronomical computer.

Two dials on the front show the zodiac and a calendar of the days of the year that can be adjusted for leap years. Metal pointers show the positions in the zodiac of the sun, moon and five planets known in antiquity. Two spiral dials on the back show the cycles of the moon and predict eclipses.

Using more powerful computers to analyze the CT data, Freeth and his colleagues, all affiliated with the in Cardiff, Wales, were able to decipher the names of all 12 months, as well as names identifying several Greek games.

The month names indicate that device probably was not from Rhodes, as originally thought, but from Corinth or one of its colonies, such as Syracuse -- home of the famed astronomer Archimedes, who lived a century before the device was made. Seven of the month names had a possible link to Syracuse.

The Metonic calendar that was used had months that averaged 30 days, with one day omitted every 64th day in order to have the correct average month length over the entire Metonic cycle of 19 years.

The key to the Olympiad Dial was the discovery of the words "NEMEA," "ISTHMIA," "PYTHIA" and "OLYMPIA."

The first reference is to the Nemean Games, one of the events that were part of the four-year cycles that climaxed with the Olympics. Isthmia represented the games at Corinth, Pythia those at Delphi and Olympia the Olympics themselves.

This dial puts the mechanism "under a considerably different light, as it tells us that, for all its technological and scientific sophistication, it was not purely a 'scientific' object, but rather also displayed information of relevance to civil life," Charette said.

Title: Re: ANTIKYTHERA Mechanism
Post by: Boreas on August 06, 2008, 06:52:38 pm

Title: Re: ANTIKYTHERA Mechanism
Post by: Bianca on August 06, 2008, 10:13:59 pm


Streaming Video:


Nature 454, 614-617

(31 July 2008)

| doi:10.1038/nature07130;

Received 28 March 2008;

Accepted 2 June 2008

Calendars with Olympiad display and eclipse prediction on the Antikythera Mechanism
Tony Freeth1,2, Alexander Jones3, John M. Steele4 & Yanis Bitsakis1,5

Antikythera Mechanism Research Project, 3 Tyrwhitt Crescent, Roath Park, Cardiff CF23 5QP, UK
Images First Ltd, 10 Hereford Road, South Ealing, London W5 4SE, UK

Institute for the Study of the Ancient World, 15 East 84th Street, New York, New York 10028, USA

Department of Physics, University of Durham, Rochester Building, South Road, Durham DH1 3LE, UK
Centre for History and Palaeography, 3,

P. Skouze str., GR-10560 Athens, Greece

Correspondence to: Tony Freeth1,2 Correspondence and requests for materials should be addressed to T.F. (Email:

Previous research on the Antikythera Mechanism established a highly complex ancient Greek geared mechanism with front and back output dials1, 2, 3, 4, 5, 6, 7.

The upper back dial is a 19-year calendar, based on the Metonic cycle, arranged as a five-turn spiral1, 6, 8.

The lower back dial is a Saros eclipse-prediction dial, arranged as a four-turn spiral of 223 lunar months, with glyphs indicating eclipse predictions6. Here we add surprising findings concerning these back dials.

Though no month names on the Metonic calendar were previously known, we have now identified all 12 months, which are unexpectedly of Corinthian origin.

The Corinthian colonies of northwestern Greece or Syracuse in Sicily are leading contenders—the latter suggesting a heritage going back to Archimedes. Calendars with excluded days to regulate month lengths, described in a first century bc source9, have hitherto been dismissed as implausible10, 11.

We demonstrate their existence in the Antikythera calendar, and in the process establish why the Metonic dial has five turns. The upper subsidiary dial is not a 76-year Callippic dial as previously thought8, but follows the four-year cycle of the Olympiad and its associated Panhellenic Games. Newly identified index letters in each glyph on the Saros dial show that a previous reconstruction needs modification6.

We explore models for generating the unusual glyph distribution, and show how the eclipse times appear to be contradictory.

We explain the four turns of the Saros dial in terms of the full moon cycle and the Exeligmos dial as indicating a necessary correction to the predicted eclipse times. The new results on the Metonic calendar, Olympiad dial and
eclipse prediction link the cycles of human institutions with the celestial cycles embedded in the Mechanism's gearwork.

Title: Re: ANTIKYTHERA Mechanism
Post by: Bianca on August 15, 2008, 08:31:35 pm

The Antikythera mechanism (IPA: [ˌæntɪkɪˈθɪərə], an-ti-ki-theer-uh; Greek: IPA: [ˌɑndiˈkiθirɑ], ahn-dee-kee-thee-rah), is an ancient mechanical calculator (also described as the first known "mechanical computer"  designed to calculate astronomical positions.

It was discovered in the Antikythera wreck off the Greek island of Antikythera, between Kythera and Crete, in 1900.

Subsequent investigation, particularly in 2006, dated it to about 150–100 BC, and hypothesised that it was on board a ship that sank en route from the Greek island of Rhodes to Rome.

Technological artifacts of similar complexity did not reappear until a thousand years later.

Title: Re: ANTIKYTHERA Mechanism
Post by: Bianca on August 15, 2008, 08:34:48 pm


In early 1901, a Greek sponge diver named Elias Stadiatos discovered the wreck of an ancient large cargo ship off Antikythera island at a depth of 42 m (138 ft) to 60 m (200 ft).

Sponge divers retrieved several statues (including the famous Antikythera Ephebe) and other artifacts from the site, known as the Antikythera wreck.

The mechanism itself was discovered on 17 May 1902, when archaeologist Valerios Stais noticed that
a piece of rock recovered from the site had a gear wheel embedded in it. Examination revealed that the "rock" was in fact a heavily encrusted and corroded mechanism that had survived the shipwreck in three main parts, and dozens of smaller fragments.

The device itself was surprisingly thin, about 33 cm (13 in) high, 17 cm (6.7 in) wide, and 9 cm (3.5 in) thick, made of bronze and originally mounted in a wooden frame (a very small part of it is still in the museum).

It was inscribed with a text of over 3,000 characters, most of which have only recently been deciphered. These were part of a manual, which describes how to set up the instrument and how to use it for observations, with references to the Sun, the motion of the planets (stationary points), Aphrodite (Venus), Hermes (Mercury), and eclipses.

Jacques-Yves Cousteau visited the wreck for the last time in 1978, but found no more remains of the Antikythera Mechanism. Professor Michael Edmunds of Cardiff University who led the study of the mechanism said: "This device is just extraordinary, the only thing of its kind. The design is beautiful, the astronomy is exactly right. The way the mechanics are designed just makes your jaw drop. Whoever has done this has done it extremely carefully." He added: " terms of historic and scarcity value, I have to regard this mechanism as being more valuable than the Mona Lisa."

The device is displayed in the Bronze Collection of the National Archaeological Museum of Athens, accompanied by a reconstruction made and offered to the museum by Derek de Solla Price. Other reconstructions are on display at the American Computer Museum in Bozeman, Montana and the Children's Museum of Manhattan in New York.

Title: Re: ANTIKYTHERA Mechanism
Post by: Bianca on August 15, 2008, 08:38:57 pm


The mechanism is the oldest known complex scientific instrument.

It has several accurate scales, and is essentially an analog computer made with gears. It is based on theories of astronomy and mathematics developed by Greek astronomers.

It is estimated that it was constructed around 150 to 100 BC. The circumstances under which it came to be on the cargo ship are unclear. The ship is estimated to have sunk between 80 to 60 BC and was a Roman or Greek ship with cargo for Rome, perhaps part of official loot. It contained more than 100 statues similar to the ones the Romans took to Italy after their conquest of Greece.

Consensus among scholars is that the mechanism itself was made in Greece.  All the instructions of the mechanism are written in Greek.

One hypothesis is that the device was constructed at an academy founded by the ancient Stoic philosopher Posidonius on the Greek island of Rhodes, which at the time was known as a centre of astronomy and mechanical engineering. Investigators have suggested that the ship could have been carrying it to Rome, together with other treasure looted from the island to support a triumphal parade being staged by Julius Caesar.

As the new finds of the Antikythera Mechanism Research Project suggest that it was made around 150 to 100 BC, well before the time of Posidonius, it is possible that the astronomer Hipparchus was the engineer who constructed it. Hipparchus was the most important astronomer of that time and worked for a long period in Rhodes, Greece. The Mechanism contains a lunar mechanism which uses Hipparchus' theory for the motion of the Moon and this also suggests strong ties of the Mechanism to Hipparchus.

The most recent published findings of The Antikythera Mechanism Research Project, as published in the July 30, 2008 edition of Nature, indicate that the concept for the mechanism originated in the colonies of Corinth in Sicily which implies a connection with Archimedes.

Title: Re: ANTIKYTHERA Mechanism
Post by: Bianca on August 15, 2008, 08:44:09 pm


The device is remarkable for the level of miniaturization and for the complexity of its parts, which is comparable to that of 18th century clocks. It has over 30 gears, although Michael Wright has suggested as many as 72 gears, with teeth formed through equilateral triangles. When a date was entered via a crank (now lost), the mechanism calculated the position of the Sun, Moon or other astronomical information such as the location of other planets.

It is possible that the mechanism is based on heliocentric principles, rather than the then-dominant geocentric view espoused by Aristotle and others. The heliocentric view proposed by Aristarchus of Samos (310 BC - c. 230 BC) did not receive widespread recognition, but provides for the possibility of the existence of such a system at this time.

The mechanism has three main dials, one on the front, and two on the back.

The front dial has two concentric scales. The outer ring is marked off with the days of the 365-day Egyptian calendar, or the Sothic year, based on the Sothic cycle. Inside this, there is a second dial marked with the Greek signs of the Zodiac and divided into degrees. The calendar dial can be moved to adjust, to compensate for the effect of the extra quarter day in the year (there are almost 365.25 days per year) by turning the scale backwards one day every four years.

Note that the Julian calendar, the first calendar of the region to contain leap years, was not introduced until about 46 B.C., up to a century after the device was said to have been built (and it was implemented with errors until the early first century).

The front dial probably carried at least three hands, one showing the date, and two others showing the positions of the Sun and the Moon. The Moon indicator is adjusted to show the first anomaly of the Moon's orbit. It is reasonable to suppose the Sun indicator had a similar adjustment, but any gearing for this mechanism (if it existed) has been lost. The front dial also includes a second mechanism with a spherical model of the Moon that displays the lunar phase.

There is reference in the inscriptions for the planets Mars and Venus, and it would have certainly been within the capabilities of the maker of this mechanism to include gearing to show their positions. There is some speculation that the mechanism may have had indicators for all the five planets known to the Greeks. None of the gearing, except for one unaccounted gear, for such planetary mechanisms survives.

Finally, the front dial includes a parapegma, a precursor to the modern day Almanac, which was used to mark the rising and setting of specific stars. Each star is thought to be identified by Greek characters which cross reference details inscribed on the mechanism.

The upper back dial is in the form of a spiral, with 47 divisions per turn, displaying the 235 months of the 19 year Metonic cycle. This dial contains a smaller subsidiary dial which displays the 76 year Callippic cycle. (There are 4 Metonic cycles within 1 Callippic cycle.) Both of these cycles are important in fixing calendars.

The lower back dial is also in the form of a spiral, with 223 divisions showing the Saros cycle; it also has a smaller subsidiary dial which displays the 54 year "Triple Saros" or "Exeligmos" cycle. (The Saros cycle, discovered by the Chaldeans, is a period of approximately 18 years 11 days 8 hours -- the length of time between occurrences of a particular eclipse.)

The Antikythera Mechanism Research Project, with experts from Britain, Greece and the United States, detected in July 2008 the word "Olympia" on a bronze dial thought to display the 76 year Callippic cycle, as well as the names of other games in ancient Greece, and probably used to track dates of the ancient Olympic games.

According to BBC news,

"The four sectors of the dial are inscribed with a year number and two Panhellenic Games: the "crown" games of Isthmia, Olympia, Nemea and Pythia; and two lesser games: Naa (held at Dodona) and a second game which has not yet been deciphered".

Title: Re: ANTIKYTHERA Mechanism
Post by: Bianca on August 15, 2008, 08:49:25 pm

Speculation about its purpose

While a century of research is finally answering the question of what the mechanism did, we are actually no nearer to answering the question of what it was for. There are numerous suggestions, any of which could be right. In order to understand the significance of this device at the period of its manufacture (c. 150 B.C.) one should be aware of the known scientific and cultural status at that period and take into account that:

The law of gravity was not discovered, so the reason for the movement of the heavenly bodies was not understood.

The theory of planetary motion was not complete.

The only means of transmitting knowledge were either speech or handwritten manuscripts.

However, it is not necessary to have a theory of planetary motion to compute planetary positions. The Babylonian 'System B', the mathematical formulae which calculated planetary positions, and which the Greeks inherited, was devised by 260 BCE, and perhaps as early as 500 BCE.

There was a huge scientific and cultural gap between the very few educated elite who understood basic rules of solar, lunar and planetary motion and the common people who were ignorant of those things. Many ancient references from Cicero, Pliny, Plato, Seneca, Ptolemy, Aristotle et al indicate that common people viewed solar and lunar eclipses as supernatural events, linked with fear: "... easy for the ignorant to imagine that all has become confusion and doom".

Practical uses of this device have also been said to include the following:

Astrology was commonly practiced in the ancient world. In order to create an astrological chart, the configuration of the heavens at a particular point of time is needed. It can be very difficult and time-consuming to work this out by hand, and a mechanism such as this would have made an astrologer's work much easier.

Setting the dates of religious festivals connected with astronomical events.

Adjusting calendars, which were based on lunar cycles as well as the solar year.

Price suggested that it might have been on public display, possibly in a museum or public hall in Rhodes. The island was known for its displays of mechanical engineering, particularly automata, which apparently were a specialty of the Rhodians. Pindar, one of the nine lyric poets of ancient Greece, said this of Rhodes in his seventh Olympic Ode:

"The animated figures stand

Adorning every public street

And seem to breathe in stone, or

Move their marble feet."

Arguments against it being on public display include:

a) The device is rather small, indicating that the designer was aiming for compactness (it has been compared to a modern laptop computer) and, as a result, the size of the front and back dials is unsuitable for public display. A simple comparison with size of the Tower of the Winds in Athens could give us a hint to suggest that the aim of the Antikythera mechanism manufacturer was the mobility of this device rather than its public display in a fixed place (such as a university, a temple, a museum or public hall).

b) The mechanism had door plates attached to it that contain at least 2000 characters, forming what members of the Antikythera mechanism research project often refer to as an instruction manual for the mechanism. The neat attachment of this manual to the mechanism itself implies ease of transport and personal use.

c) The existence of this "instruction manual" implies that the device was constructed by an expert scientist and mechanic in order to be used by a non-expert traveler (the text gives a lot of information associated with well known geographical locations of the Mediterranean area[citation needed]).
The device is unlikely to have been intended for navigation use because:

a) Some data, such as eclipse predictions, are unnecessary for navigation.

b) The harsh environment of the sea would corrode the gears in a short period of time, rendering it useless.

On 30 July 2008, scientists reported new findings in the journal Nature showing that the mechanism tracked the Metonic calendar, predicted solar eclipses, and calculated the timing of the Ancient Olympic Games.

Inscriptions on the instrument closely match the names of the months on calendars from Illyria and Epirus in northwestern Greece and with the island of Corfu.

Title: Re: ANTIKYTHERA Mechanism
Post by: Bianca on August 15, 2008, 08:57:42 pm

Similar devices in ancient literature

Cicero's De re publica, a 1st century BC philosophical dialogue, mentions two machines that function as a planetarium or orrery, predicting the movements of the Sun, the Moon, and the five planets.

The first device was built by Archimedes and brought to Rome by the Roman general Marcus Claudius Marcellus after the death of Archimedes at the siege of Syracuse in 212 BC. Marcellus had a high respect for Archimedes and this was the only item he kept from the siege. The device was kept as a family heirloom, and Cicero was shown it by Gallus about 150 years later. Gallus gave a 'learned explanation' of it and demonstrated it for Cicero.

"Hanc sphaeram Gallus cum moveret, fiebat ut soli luna totidem conversionibus in aere illo quot diebus in ipso caelo succederet, ex quo et in [caelo] sphaera solis fieret eadem illa defectio, et incideret luna tum in eam metam quae esset umbra terrae, cum sol e regione."

When Gallus moved the globe, it happened that the Moon followed the Sun by as many turns on that bronze [contrivance] as in the Earth itself, from which also in the sky the Sun's globe became [to have] that same eclipse, and the Moon came then to that position which was [its] shadow [on] the Earth, when the Sun was in line.

Pappus of Alexandria stated that Archimedes had written a now lost manuscript on the construction of these devices entitled On Sphere-Making.

The surviving texts from the Library of Alexandria describe many of his creations, some even containing simple blueprints. One such device is his odometer, the exact model later used by the Romans to place their mile markers (described by Vitruvius, Heron of Alexandria and in the time of Emperor Commodus)The blueprints in the text appeared functional, but attempts to build them as pictured had failed. When the gears pictured, which had square teeth, were replaced with gears of the type in the Antikythera mechanism, which were angled, the device was perfectly functional.

Whether this is an example of a device created by Archimedes and described by texts lost in the burning of the Library of Alexandria, or if it is a device based on his discoveries, or if it has anything to do with him at all, is debatable.

If Cicero's account is correct (and there is reason to doubt it), then this technology existed as early as the 3rd century BC. Archimedes' device is also mentioned by later Roman era writers such as Lactantius (Divinarum Institutionum Libri VII), Claudian (In sphaeram Archimedes), and Proclus (Commentary on the first book of Euclid's Elements of Geometry) in the 4th and 5th centuries.

Cicero also says that another such device was built 'recently' by his friend Posidonius, "... each one of the revolutions of which brings about the same movement in the Sun and Moon and five wandering stars [planets] as is brought about each day and night in the heavens..."

It is unlikely that either of these machines were the Antikythera mechanism found in the shipwreck, because both the devices mentioned by Cicero were located in Rome at least 50 years later than the estimated date of the shipwreck. So we know of three such devices. The modern scientists who have reconstructed the Antikythera mechanism also agree that it was too sophisticated to have been a one-off device.

It is probable that the Antikythera mechanism was not unique, as shown by Cicero's references to such mechanisms.

This adds support to the idea that there was an ancient Greek tradition of complex mechanical technology that was later transmitted to the Islamic world, where similarly complex mechanical devices were built by Muslim engineers and astronomers during the Middle Ages.

In the early 9th century, the Banū Mūsā's Kitab al-Hiyal (Book of Ingenious Devices), commissioned by the Caliph of Baghdad, describes over a hundred mechanical devices, some of which may date back to ancient Greek texts preserved in monasteries. Similarly complex astronomical instruments were constructed by al-Biruni and other Muslim astronomers from the 11th century.

Such knowledge could have yielded to or been integrated with European clockmaking and medieval cranes.


Title: Re: ANTIKYTHERA Mechanism
Post by: Bianca on January 09, 2009, 08:47:46 am

                    Decoding the Heavens: Solving the Mystery of the World’s First Computer

                     by Jo Marchant - review

        Ed Lake uncovers the story of the Antikythera mechanism, a 2,000-year old piece of clockwork

By Ed Lake
Last Updated: 11:21AM GMT 08 Jan 2009

Astonishing archaeological discoveries, those that send even the most staid archivist into reveries about ancient astronauts and time travellers, are disappointingly rare. There is an iron pillar in Delhi erected around 900 BC that has hardly rusted; the so-called “Baghdad battery” – a Sassanid pot that may or may not have been an electrochemical cell, though it hardly matters since it has nowhere to attach wires. But these are slim pickings.

The only item with a decent claim to have upset the established record is the Antikythera mechanism, a 2,000-year-old lump of corroded bronze that is the most exquisite piece of pre-18th-century clockwork that we possess. In 1901, a team of Greek sponge divers was investigating an ancient shipwreck off the coast of Antikythera.

Along with a haul of bronze statuary and some potsherds that proved useful for dating the vessel, it happened on a few chunks of encrusted greenish limestone from which, puzzlingly, gears were protruding. This should, so to speak, have set off alarm bells: up until then the entire tradition of European clockwork was thought to stem from 10th-century Arabia; the flowering of this art in the 15th century was what inspired the mechanistic ideas of Descartes and Laplace, which, in turn, laid the foundations for the technological triumphs of the following centuries. In other words, those few cogs should have caused a major upset in the history of thought.

Instead, the chunks were left for several years in a crate outside the Athens National Archaeological Museum. On contact with the air, hydrochloric acid started forming around the surviving fragments, eating away at their workings. By the time anyone got round to inspecting the device, it was very difficult to see what it could have been. The story of how it has been pieced back together over the past 50 years is the main theme of Jo Marchant’s diverting book.

Choosing to focus on this aspect of the subject might have been a mistake, however, as the tale pans out very much as you might guess. It all came down to improvements in 3D imaging technology – Cat scans, essentially – combined with the clock-building intuition of scholars. There aren’t many twists to lighten the exposition, though Marchant does set up a satisfyingly bitter race for the prize. Michael Wright, a British savant, wore out his health, marriage and job trying to reconstruct the device through his mechanical intelligence. When he found himself beaten by a documentary filmmaker who used flash-tomography equipment, he turned up at his rival’s party to deliver what a witness called: “half an hour of continuously controlled rage”. Having heard what he went through, I don’t blame him.

Yet despite such heightened passions, the participants in Marchant’s drama remain for the most part indistinct. We get very little quotation to suggest tone of voice, and character is largely sketched through cliché: “Field was a careful scholar, fiercely proud of her PhD”; “Agamemnon is… a large but gentle bear of a man” and so on. One gets an impression of anxious mollification, as if Marchant thought her interview subjects would revolt unless portrayed as heroes.

None of this detracts greatly from the main interest: the device. Marchant calls it a computer, which seems a stretch since it wasn’t in any sense programmable, but it’s a dizzyingly brilliant thing regardless. A mechanical calendar, it gave the positions of the stars, quite possibly predicted eclipses, and might, rather unconventionally for the time, have placed the sun instead of the Earth at the centre of the cosmos.

Michael Wright believes the device originally possessed 72 gears. Those that survive are so tiny and perfectly cut, not to mention arranged in so elegant a mechanism, as to suggest a mature tradition in clockwork that has not survived. Bronze was a scarce commodity, often recycled. Medieval scribes tended to copy only those treatises of the ancients which they could understand. In this way, pinnacles of human ingenuity recede. Whatever else it might once have told its creators, the Antikythera mechanism bears a chilling message for our technological age.

Title: Re: ANTIKYTHERA Mechanism
Post by: Bianca on August 10, 2009, 10:01:07 am

                                  World's first computer may be even older than thought

Jo Marchant,
July 29, 2009

From Swiss Army knives to iPhones, it seems we just love fancy gadgets with as many different functions as possible. And judging from the ancient Greek Antikythera mechanism, the desire to
impress with the latest multipurpose must-have item goes back at least 2000 years.

This mysterious box of tricks was a portable clockwork computer, dating from the first or second century BC. Operated by turning a handle on the side, it modelled the movements of the Sun, Moon
and planets through the sky, sported a local calendar, star calendar and Moon-phase display, and
could even predict eclipses and track the timing of the Olympic games.

I gave a talk on the device at London's Royal Institution last night. One new clue I mentioned to the origin of the mechanism comes from the Olympiad dial - there are six sets of games named on the dial, five of which have been deciphered so far. Four of them, including the Olympics, were major games known across the Greek world. But the fifth, Naa, was much smaller, and would only have been of local interest.

The Naa games were held in Dodona in northwestern Greece, so Alexander Jones of the Institute
for the Study of the Ancient World in New York has suggested that the mechanism must have been made by or for someone from that area.

Intriguingly, this could mean the device is even older than thought. The inscriptions have been dated
to around 100 BC, but according to Jones the device may have been made at latest in the early second century BC, because after that the Romans devastated or took over the Greek colonies in the region,
so it's unlikely that people would still have been using the Greek calendar there.

But the highlight for most of the audience - judging from the spontaneous round of applause it received -was this breathtaking new animation of the gearing inside the mechanism. It has been made by Mogi Vicentini, an Italian astronomer and computer scientist, and it brings the device to life brilliantly.

Judge for yourself, but I think it shows that the mechanism would hold its own against the best of today's luxury gadgets.

Jo Marchant is author of Decoding the Heavens, a book about the Antikythera mechanism. It has
been shortlisted for the 2009 Royal Society Prize for Science Books, and is out now in paperback.

Categories: Science In Society | Technology

Tags: antikythera mechanism

Posted on July 29, 2009

Title: Re: ANTIKYTHERA Mechanism
Post by: Seer of Dark Things on December 02, 2014, 01:29:38 am

James Evans and Christián Carman Find Clues to an Ancient Greek Riddle
November 25, 2014
 Discovery about the Antikythera Mechanism
reveals surprising advances in early Greek science

An ancient Greek astronomical puzzle now has another piece in place.

The New York Times reported the new evidence today in a story about research by James Evans, professor of physics at University of Puget Sound, and Christián Carman, history of science professor at University of Quilmes, Argentina.

The two researchers published a paper advancing our understanding of the Antikythera Mechanism, an ancient Greek mechanism that modeled the known universe of 2,000 years ago. The heavily encrusted, clocklike mechanism—dubbed the “world’s first computer”—was retrieved from an ancient shipwreck on the bottom of the sea off Greece in 1901.  The new work is published in the Archive for History of Exact Science.

After several years of studying the mechanism and Babylonian records of eclipses, the collaborators have pinpointed the date when the mechanism was timed to begin—205 B.C.  This suggests the mechanism is 50–100 years older than most researchers in the field have thought.

The new work fills a gap in ancient scientific history by indicating that the Greeks were able to predict eclipses and engineer a highly complex machine—sometimes called the world’s first computer—at an earlier stage than believed. It also supports the idea that the eclipse prediction scheme was not based on Greek trigonometry (which was nonexistent in 205 B.C.)—but on Babylonian arithmetical methods, borrowed by the Greeks.

Far more conjecturally, this timing also makes an old story told by Cicero more plausible—that a similar mechanism was created by Archimedes and carried back to Rome by the Roman general Marcellus, after the sack of Syracuse and the death of Archimedes in 212 B.C. If the Antikythera mechanism did indeed use an eclipse predictor that worked best for a cycle starting in 205 BC, the likely origin of this machine is tantalizingly close to the lifetime of Archimedes.

Evans and Carman arrived at the 205 B.C. date using a method of elimination that they devised. Beginning with the hundreds of ways that the Antikythera’s eclipse patterns could fit Babylonian records (as reconstructed by John Steele, Brown University) the team used their system to eliminate dates successively, until they had a single possibility.

 The calculations take into account lunar and solar anomalies (which result in faster or slower velocity), missing solar eclipses, lunar and solar eclipse­s cycles, and other astronomical phenomena. The work was particularly difficult because only about a third of the Antikythera’s eclipse predictor is preserved.

Evans and Carman first presented their ongoing research at a Netherlands conference in June 2013, stimulating debate among their peers.  The new online paper will appear in the journal’s January 2015 hard copy edition.

To read The New York Times story visit:

Photos on page: Top right: the ancient Antikythera relic rescued from a shipwreck (photo by Giovanni Dall Orto). Above left: James Evans, by Ross Mulhausen.

Tweet this: Scientific whodunit #Antikythera. James Evans @univpugetsound adds a clue. Story by @markoff @nytimes

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Title: Re: ANTIKYTHERA Mechanism
Post by: Seer of Dark Things on December 02, 2014, 01:30:27 am