Announcement

Collapse
No announcement yet.

Antikythera mechanism, 2000 year old machine?

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • #31
    Originally posted by Doc Nickel View Post
    While Clickspring hasn't- and can't, of course- proven that the mechanism absolutely could have been made with period tools,
    I thought the original modern maker was a British curator of a museum, build one in his shed with hand tools to demonstrate it could be built. dim recollection from a video once seen
    in Toronto Ontario - where are you?

    Comment


    • #32
      Originally posted by Mcgyver View Post

      I thought the original modern maker was a British curator of a museum, build one in his shed with hand tools to demonstrate it could be built. dim recollection from a video once seen
      His name was Michael T. Wright and he was a curator of Mechanical Engineering at the UK Natural History and Science Museum in London. A friend of mine worked there his whole life as an archivist and knew Michael. Apparently he was an extremely clever man of far reaching interests, and slightly eccentric (in the true British tradition). My friend said that he even ground up his own spectacle lenses - presumably just because he could!

      Ian.

      Comment


      • #33
        Ian, thanks for filling in the details. The Science Museum is a marvel, a highlight of a London visit for us mechanical types
        in Toronto Ontario - where are you?

        Comment


        • #34
          Originally posted by Corbettprime View Post

          Considering the mathematics involved alone, could someone explain how to lay out the diameter and spacing on the gear, without knowing the value on Pi? Has there been any evidence of files that small and precise ever been found? What other method of forming gear teeth could have been used? In order to make a file, you need a chisel. For both those, you need steel, and the knowledge of how to heat treat it. How would you lay out the spacing for each of the different diameters involved. I'm not not from Missoui, but SHOW ME! The old Greeks were quite proficient at mathematics, but I would like to know how they made those gears,
          I can't answer all your objections - I doubt anyone could - but here are some things to consider...

          The ancient Greeks certainly knew the value of pi, not to the precision we have today (many millions of digits), but to an accuracy consistent with their use of it.

          They knew 22/7 which has less than 1% error...

          22 / 7 = 3.142857142857 (0.04 %)

          and may well have known (due to their proximity to the silk road) the Chinese form that is far more precise...

          Tsu Chung Chi approximation: 355 / 113 = 3.141592920354 (0.0000085 %)

          but you don't need to know pi to subdivide the circle into CERTAIN subdivisions with only straightedge and compass. Here's an extract from my personal notebook that explains what is possible...

          ----------------------

          WHY YOU CAN'T DIVIDE A CIRCLE INTO SEVEN SEGMENTS WITH COMPASS AND STRAIGHTEDGE

          The famous German scientist Gauss proved 200 years ago that a circle can be divided into N equal parts (N=2,3,...) ONLY when N has a form:

          N = 2^k*p1*p2*....pm (k=0,1,2,3,...)

          p1, p2, ..., pm are "m" DISTINCT prime numbers (m=0,1,2,...), each of the form 2^(2^q) + 1 (so called Fermat primes, q=0,1,2,...).

          When m=0, we have N=2^k and so N = 2, 4, 8, 16,... etc. are posible divisions

          With N=3 = 2^(2^0) + 1, so you can divide a circle into 3, 6, 12, 24 etc. parts

          With N=5 = 2^(2^1) + 1, so you can divide a circle into 5, 10, 20, 40 etc. parts.

          Now take N = 65537 = 2^(2^4) + 1. It is said that in Goettingen University in Germany there is a manuscript describing the division into 65537 parts!

          7 is a prime number, but NOT FERMAT PRIME, that's why division into 7 equal parts is not possible. Neither is possible into 9, because 9 = 3*3, both 3's ARE FERMAT primes, but NOT DISTINCT.

          ----------------------

          They may not have had steel, but they certainly had bronze; their weapons were made of it and plenty have been recovered. With arsenic as a hardening agent and driven by military need, they probably could fabricate alloys of varying degrees of hardness. (The ancient Egyptians made bronze chisels from copper and arsenic and used them to build the pyramids. ) That opens the door for hard tools used to shape softer bronze tools which, in turn, are used to shape much softer gears. (Wear on a seldom used calculator isn't much of an issue.) The nitty-gritty of Greek metal fabrication requires metallurgist-trained archaeologists and that's way out of my wheel house.

          The Greeks were sophisticated astronomers. They had figured out that the earth was spherical and measured its diameter with surprising accuracy. Their cosmology was not heliocentric but you can do a damn good job modeling the motion of the then known planets with epicycles, which they did. I suspect the mechanism is based on an epicyclic model but can't say with confidence.

          The fact that one can't imagine how they did things speaks to limits on one's knowledge and imagination and doesn't represent a limit on their accomplishments.




          Regards, Marv

          Home Shop Freeware - Tools for People Who Build Things
          http://www.myvirtualnetwork.com/mklotz

          Location: LA, CA, USA

          Comment


          • #35
            Im thinking the thing was most likely rubbish to begin with and that's why it ended up at the bottom of the sea,,, probably worked for a little bit and then started skipping gears when someone tried to "rush it" a little, also keep in mind it could not have made much sense due to them missing the fact that things actually revolved around the sun not the earth, so it's about as good as a 23 hour a day clock,

            I can absolutely almost guarantee you that just before the thing got "wet" all kinds of shouting on the vessel was heard of "she's taking on water" and "grab the goods" and such, probably explains the lack of wine casks in the wreckage area and why this thing was found in the first place...

            Comment


            • #36
              Originally posted by A.K. Boomer View Post
              ... keep in mind it could not have made much sense due to them missing the fact that things actually revolved around the sun not the earth...
              I guess you missed what I said about epicycles.

              Regards, Marv

              Home Shop Freeware - Tools for People Who Build Things
              http://www.myvirtualnetwork.com/mklotz

              Location: LA, CA, USA

              Comment


              • #37
                Originally posted by mklotz View Post

                I guess you missed what I said about epicycles.
                I tried one of those once but prefer two wheels...

                Comment


                • #38
                  Originally posted by Mcgyver View Post
                  I thought the original modern maker was a British curator of a museum, build one in his shed with hand tools to demonstrate it could be built. dim recollection from a video once seen
                  -It's possible somebody did. As I understand it, several copies have been made over the years. Keeping in mind the device was originally discovered in 1901, so it's had over a century of analysis.

                  Earlier iterations likely had to make more guesses about the mechanism, as X-ray technology wasn't as advanced as it is today. Clickspring discovered what he did- that a secondary dial recorded something like Egyptian months, not modern lunar months, or something like that- because of very recent high-accuracy, high-resolution digital 3D X-ray imaging that was done, and the results posted to the internet.

                  From those, Chris was also able to determine- still with some guessing, but a lot less than before- about how the physical mechanism was constructed. That is, which parts were staked, which were pinned, which were soldered, etc.

                  So while there are already several copies extant, Clickspring's will almost certainly be the most accurate reproduction once it's complete.

                  Doc.

                  Doc's Machine. (Probably not what you expect.)

                  Comment


                  • #39
                    As others have said, click spring created and documented a copy of the mechanism using tools and techniques that were likely to have been available at the time.

                    There is currently debate over other functionality the device may have had but the proposed function would have required a precision lathe.

                    More about the current debate here:

                    https://www.bbc.com/news/science-environment-56377567
                    ​​​​​

                    Comment


                    • #40
                      "If someone in 0020 found a smartphone manufactured in 2020 how would they describe it?"
                      A1: " Hey, I bet you 1000 grains of salt that I can skip this thing better than you can skip that flat stone"...

                      A2: " This is clearly evil....pure evil....burn it"
                      S E Michigan

                      Comment


                      • #41
                        What amazes me about Clickspring (besides the extensive research and skills) is that he even went so far as to make his own files, and took the time to investigate ancient means of "marking out" with various liquid solutions, waxes, plant resins, and smokes/soot.
                        Location: Northern WI

                        Comment


                        • #42
                          Originally posted by Galaxie View Post
                          What amazes me about Clickspring (besides the extensive research and skills) is that he even went so far as to make his own files, and took the time to investigate ancient means of "marking out" with various liquid solutions, waxes, plant resins, and smokes/soot.
                          He's almost as smart as the guy who made the original.

                          Comment


                          • #43
                            Originally posted by Commander_Chaos View Post

                            He's almost as smart as the guy who made the original.
                            Copy vs. designing
                            Helder Ferreira
                            Setubal, Portugal

                            Comment


                            • #44
                              Well, arguably Clickspring is having to reverse-engineer a mechanism that's been badly damaged and corroded by being in salt water for literally over a millennia, and of which they only have about 70 percent of.

                              I'd say both were brilliant.

                              Doc.
                              Doc's Machine. (Probably not what you expect.)

                              Comment


                              • #45
                                Originally posted by Commander_Chaos View Post

                                He's almost as smart as the guy who made the original.
                                Probably smarter, if he can find a good hiding place for it in case the Romans sack Australia
                                I just need one more tool,just one!

                                Comment

                                Working...
                                X