Ancient Astronomical Computer Decoded 233
slimjim8094 writes "A mechanical device from 150BC was found in a shipwreck. Upon examination with X-Rays, the device appeared to be a revolutionary computer used to calculate lunar cycles. This device "is technically more complex than any known for at least a millennium afterward." From the article
"The hand-operated mechanism, presumably used in preparing calendars for planting and harvesting and fixing religious festivals, had at least 30, possibly 37, hand-cut bronze gear-wheels, the researchers said. A pin-and-slot device connecting two gear-wheels induced variations in the representation of lunar motions according to the Hipparchos model of the Moon's elliptical orbit around Earth."
What mysterious tommorow devices from today? (Score:3, Interesting)
Currently I have a Nixie clock for the same 'guest amusement' function. In several millennium when this creation is rediscovered it will seem oddly complex and mysterious. Bill Gates and Scott McNealy, what mysterious technical devices are in your living room?
So whats a Nixie? Forgot already have we? Jeff Thomas and Laurence Wilkins build good Nixie clocks.
http://www.amug.org/~jthomas/clockpage.html [amug.org]
Cheers,
Jim Burke
Sophistication - Math or machine? (Score:3, Interesting)
Re:So it's an astrolabe? (Score:2, Interesting)
Computer? (Score:1, Interesting)
Math wise, simple yet briliant (Score:5, Interesting)
Simple math that we all can understand.
The sun gear has 64 teeth.
It meshes with the smaller of a 38,48 gear pair.
The 48 meshes with the smaller of a 24,127 gear pair.
The 127 meshes with the 32 teeth of the moon gear.
The ratio of angular speeds can then be calculated as (64/38) x (48/24) x (127/32)=(254/19) = 13.36842..
which is an excellent approximation of the astronomical ratio 13.368267..
This corresponds with the Metonic cycle, in which 19 solar years correspond exactly with 235 lunations,and therefore with 254 sidereal revolutions of the Moon.
Thus. for every 19 (direct) turns of the main drive wheel; this produces 2,356/2 revolutions of the whole differential turntable, and all the gears mounted upon it.
This is just awsome. You can pin point where the moon will be located, just by turning one wheel a certain number of time, according to what year is it. Thus, you can tell what the tide will look like days, weeks, months ahead of your trip at sea.
How come this device died and disapeared for centuries? Given the Egyptians knowledge of the earths equinox, this was the key to discover America way before Colombus did.
Ancient Computations (Score:1, Interesting)
http://hardware.slashdot.org/comments.pl?threshol
After reading the linked paper, i got the impression that our culture falsely asumes that our common view of mathematics its the best one to use... and thats the first obstacle when trying to fully understand ancient maths practices
Re:I knew it! (Score:5, Interesting)
I know you're joking, but given the fact that we're finding old stuff based on some pretty intense knowledge, I'm starting to think that Graham Hancock might be right about us being older, as a race, than we think we are. [grahamhancock.com] He attracts a lot of criticisms, but mostly from egyptologists because his interpretations of artifacts found contradict theirs. The book is an excellent read though.
Though aliens would be fun too, I suppose...
Re:Ancient Engineering (Score:2, Interesting)
yes it is regrettable when languages are lost whether we can decipher them or not, but I believe the Mayan language has at least been partially deciphered.
http://www.pauahtun.org/MayanGlyphs/syllabary.htm
http://en.wikipedia.org/wiki/Popol_Vuh [wikipedia.org]
Re:my guess: it was overly difficult to make (Score:3, Interesting)
Technology is culture. Every viable technology requires a group of practioners large enough to transmit it across generations. That means they must have the resources to train apprentices and sufficient prospect of future revenues from their work to attract capable people.
The Athenian Greek leisure class (free adult male citizens) were interested in theoretical knowledge, but looked down on the practical. Romans were interested almost exclusively in practical knowledge, and saw little or no value in the Greek passion for theory.
The Greeks were excellent mathematicians--one of the big unanswered questions in the study of ancient Greek mathematics is why they did not invent at least the conceptual basis of calculus, as they seem to have had all the precursor concepts. But the mathematicians rarely talked to the machinists, so this technology may have grown out of some rare collaboration between a practical artisan and a gifted mathematician, or it may have been a still rarer individual who combined both skills.
Curiously, the existence of such a sophisticated device makes virtually certain that some kind of viable community of skilled artisans working with micro (for the time) machinery had existed for decades or centuries prior to the construction of this device, and probably for some time after. So while the technological culture of the ancient world may have been delicate--as all technological cultures are, including our own--is was also long-lived. Its death was probably due to the general economic decline during the Western European Dark Age, rather than anything specfic to Christianity. The Dark Age actually saw significant development in many technological areas, but they tended to focus on the more practical aspects of farming and war-making than on what amounts to a wonderful yet expensive toy.
Re:Math wise, simple yet briliant (Score:3, Interesting)
Except for one part: the Mediterranean has barely any tide.
So, they would use it for other things, but not that.
single genius possible (Score:3, Interesting)
There are probably many such geniuses unrecorded in history. Writing systems appear fair ly suddenly in dyanastic Egpyt and the alphabet in Urgait. Other historians suggest long transitional phases, with some evidence. But I can equally envison some light-bulb guy doing this in a single career.
Perhaps the clock machinist was one of these geniuses.
The dark ages hit Greece? (Score:2, Interesting)
In the early middle ages, you had the reign of Justinian and continual development up through what is considered the ``golden age'' of the Byzantine Empire in the ninth to eleventh centuries. Certain aspects of technology may have been in decline, but they held on to Greek Fire and quite a few other wonders of science.
I also think you overstate the case of the Greek love of theory. One of the popular criticisms of Thales was that, as a philosopher, he was too unconcerned with practical matters. The legend goes that in response to this when he calculated that conditions were correct for a bumper olive crop, he cornered the market on olive presses and by the time the harvest came in he made a fortune.
Greek culture extended past the Mediteranean (Score:2, Interesting)
Re:The dark ages hit Greece? (Score:3, Interesting)
But for some centuries Roman intellectual and technological power was centered in the West, and it is likely that the techological community that created this device would have migrated west as Roman power grew in the 1st century. So when the Western Empire fell, there is a good chance that the community was no longer able to sustain itself, if it had not already failed due to the vast increases in economic hardship during that last century before the final division of the Empire and the collapse of the West.
Nor were things exactly great in the East at the time--Greece itself as well as most of Asia Minor was at times under "barbarian" control, and the tides of migration and conquest that flowed over the region for several hundred years would not have been conducive to maintaining the kind of fine artisanship displayed by this device.
It also isn't clear how the "Greek fire" of the Byzantines is related to that described by Thucydides: it may have be a rediscovery of a simple and practical warlike technology rather than hanging on to ancient technology. And while the Byzantine Empire wasn't without technological capability there were such huge expenditures of intellectual capability on disputes with but one iota of difference between the sides that there wasn't much intellectual power left over for practical matters.
As to the legend about Thales, it's a legend for a reason.
Lots of assumptions there (Score:2, Interesting)
For most of the Byzantine era, Byzantium was a superpower. Outside of brief but notable incursions by the Muslims (who by that time were rather heavily Hellenized) and the Bulgarians, most of Greece was under Greek control from the beginning of the Byzantine era (whether you measure the beginning from the third or from the fifth century) up through nearly the eleventh century. Additionally large swaths of southern Italy were controlled by Constantinople during this period as well as large chunks of Asia Minor. Modern scholars largely agree (contra Gibbon) that education and learning were widespread through most of the Byzantine era. And bear in mind that `barbarian' simply meant non-Greek to the Hellenes. Romans, despite being fellow citizens of the empire would would have been barbarous to them if they couldn't speak Greek.