The Antikythera Mechanism Episode 10 - Evidence Of A Lunar Calendar

[Music] [Music] g'day chris here and welcome back to clickspring after more than a century of investigation most of the features and functions of the antikythera mechanism are largely understood and this build series and the fragments videos have been mostly about presenting that known information along with figuring out some of the possible explanations of how it might have been constructed in antiquity but not surprisingly there remain a few outstanding discrepancies about the machine itself features that don't quite make sense based on the current interpretation of the evidence and others that so far have had no plausible explanation proposed now you may be aware that one of those features has ended up being a major part of this reconstruction as a parallel research project alongside the build series investigating what's turned out to be an entirely new finding it's taken a number of people several years to properly analyze and document the finding and also to navigate the academic review process the detail is best presented in the research paper itself so do give it a read at the links below but before you do i'd like to give you a bit of background on the finding and cover something that's not in the paper and that is how the discovery was made so let's start at the beginning back in early 2016 before construction had commenced you'll recall from the first episode that one of the main objectives of the project was to create an accurate replica of the mechanism it's a crucial record of what amounts to the original language of the mechanical engineer so any analysis of it can only make sense if we're dealing with a faithful reproduction so right from the start it was clear that the build needed to conform as close to the evidence as possible the published research was useful as a basic framework to start the cad modeling but mostly for gear ratios and the basic architecture there's no comprehensive presentation of dimensional or structural data in the public research so it was clear that the best approach to model the device was to essentially start from scratch and check everything against the raw data scans at the time there was a set of high resolution x-rays of the mechanism available online and this became the foundation of the build every dimension tooth count and structural feature that could be was verified or otherwise determined directly from these x-rays and then reproduced in the digital model and for the most part there were no great surprises the video series started to map itself out in advance as each feature suggested some really cool questions like what would be the minimum viable tools to make each part and what would those tools themselves need to be made of and so on now i say for the most part because there was one feature that immediately jumped out as a problem from day one of the cad modeling and that was the front dial calendar ring now partially preserved in what's known as fragment c the front dial counter ring of the mechanism is a graduated ring that lies in a channel in the front dial plate just inside it is a graduated representation of the ecliptic known as the zodiac ring about a quarter of the original dial assembly remains along with the displaced remains of what's known as the lunar phase display all on a fused corroded lump of metal oxide the calendar ring was fabricated to rotate freely within this channel underlying it is a matching arc of closely spaced holes believed to have been used to register the radial position of the ring by a small peg being inserted through the ring into any one of the underlying holes there are engravings on the surface of the ring including graduated markings that divided into what appear to be days and the remains of three consecutive egyptian month names inscribed in ancient greek now the ring is accepted to have had a calendrical function and has been universally assumed up until now to be a representation of the so-called egyptian civil calendar of 365 day duration and with good reason as mentioned the surviving section displays three egyptian civil month names adjacent to divisions that can be reasonably interpreted as days of consecutive months also the egyptian civil calendar is prominent in the historical record before during and after the presumed period of the mechanism's construction so on the surface at least it seems a reasonable proposal but as soon as we start to look closer things start to unravel the divisions on the calendar ring don't obviously appear to number 365. in fact a simple direct inspection puts the number considerably lower so an explanation is required derek desola price briefly discussed this issue in his paper gears from the greeks and he attributed the discrepancy to unintentional fabrication error subsequent researchers have since proposed various intentional non-uniform division theories but there are some obvious problems with each of these proposals firstly at no stage has anyone empirically tested the assumption that the divisions in the calendar ring do in fact number 365 the assumption has for more than 100 years been simply taken to be true certainly it's a reasonable guess especially in the days before high resolution imaging but if everything about the feature rests on that number being correct then surely it needs to be verified and it's worth pointing out that the section of an egyptian calendar that would immediately settle the matter is not present in the wreckage we have no physical evidence of the five so-called epidominal days of a typical egyptian civil calendar just egyptian month names adjacent to divisions that don't obviously appear to number 365 and secondly the proposed explanations just don't strike me as reasonable the idea of a maker capable of this level of mastery overlooking what to them at least would have been an obvious mistake and in the most visible part of the mechanism is a little jarring it's possible sure maybe the apprentice had a bad day maybe the maker just wanted it out the door to get paid but there are no comparable overlooked mistakes elsewhere in the structure to give us a reasonable precedent to support the idea in fact for the most part the work is superb and shows a tremendous attention to detail so on the evidence that we have if this is a mistake then it's an outlier and a prominent one at that that would have severely detracted from the otherwise excellent standard of work which says to me that it's not likely to be an error at all so at the time of cad modelling that left the most likely of the then proposed explanations to be that the calendar ring or the zodiac ring or maybe even both were intentionally non-uniformly divided but again based on a rough visual check that didn't fit with the evidence either the divisions for the zodiac ring are fairly evenly distributed and it's easy enough to verify that they're about right for 360 divisions the calendar ring is a little more complicated to interpret because of the cracks certainly there are small deviations here and there but nothing that clearly suggests an intentional non-uniform division what did stand out though was that the divisions were very likely to be much less than 365 and for me this was the real heart of the issue because if we had no prior assumption of the calendar ring having 365 divisions then the modern imaging wouldn't naturally lead us to consider it certainly an egyptian civil calendar has seemed a logical interpretation since the mechanism was first salvaged from the antikythera coastline and there hasn't been a compelling reason to continue to question that feature but the reconciliation of a cad model with the modern imaging casts reasonable doubt on that interpretation and the only way to know for sure of course is to carry out a detailed examination of the highest resolution images so that's what happened in addition to the physical build a small group of us have spent the last few years working to determine just what the actual number of calendaring divisions really is and here's the result a research paper presenting our finding to be formally published in the horological journal the paper is presented in two parts part one covers the key finding that the data do not support that the number of divisions of the front dial calendaring of the antikythera mechanism is 365. and proposing that in fact the number of divisions is most likely to be 354 consistent with the calendaring being a lunar calendar about this we are as certain as we can be it's there for anyone to measure and so is a testable attribute of the machine but what this new information means is a little more open to debate at minimum it implies the existence of some lost gearing to articulate a lunar calendar on the front dial as well as a reinterpretation of the purpose of the underlying calendaring holes it also plausibly resolves a few of the other outstanding issues of the mechanism structure and may even provide a resolution to a long-standing issue regarding the calendars of ancient egypt but this is an unavoidably speculative discussion that will likely play out over many years and i expect more than a few twists and turns before the dust settles so we've separated all of this out into part two of the paper to distinguish it from the core finding all of this will eventually be discussed in detail in the rest of the build series which of course has some considerable time to run now it won't have escaped your attention that it's already taken a long time to get to this point more than four years in fact from the very start of the project certainly i had no idea that it would take as long as it has so i'd like to thank you for your patience while this part of the work was completed in any event the good news is that the build series is back on and i do hope that you enjoy the rest of the series as i continue the construction and investigation of this wonderful machine thanks for watching i'll see you later [Music] you

Channel: Clickspring

Views: 392,104

Keywords:

Id: MkKgdq57uOo

Length: 10min 43sec (643 seconds)

Published: Sat Dec 12 2020

Reddit Comments

[u/SoftwareMaven]

What I love about this is that it took a real craftsman looking at it to say, “bullshit. The guy who made this was also a real craftsman and did not just screw up the number of markings for a year.” I would never want to imply that there is not real knowledge in academia, but, sometimes, you need to get your hands calloused to understand.

[u/FuckingAustralians]

At last. Wonder if it means his paper got approved.

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Guy is my kind of bonkers.

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Edit: Yeah probably should have read the pinned comment first....

[u/xylempl]

TL;DW: Chris from Clickspring is back and has published his findings about the Antikythera Mechanism (front dial calendar is a lunar, 354 days calendar, not 365 days one as previously suspected - https://bhi.co.uk/antikytheramechanism/)