There’s a 1995 PBS Nova episode in their Secrets of Lost Empires series which includes a segment on drilled granite. The episode features egyptologist Mark Lehner, stone mason Roger Hopkins, and ancient tool expert Denys Stocks.
The episode mainly explores the question of how an obelisk was raised. The team ran out of time before they were able to reach a satisfying conclusion, but they returned to Egypt in 1999 to record another NOVA episode, which includes two competing theories on how to raise an obelisk. I highly recommend both episodes.
> Photograph of a model of the bottom of the drill hole shows that lines are spaced closer together (arrow). This may be due to abrasive having become finer as drilling continued.
Anyone who has drilled brittle materials will know why the lines got closer together. The feed pressure was reduced near the end of the hole to avoid chipping out the back surface.
It's obvious Egyptians could carve granite using stone instruments. What is worth more investigation, is how they carved symmetric granite vases within 1/100th of an inch precision.
Ben from UncharteredX has a good video on these drill samples, but does not buy into the mainstream acceptance of how they were made. In fact the granite core samples show continuous grooves and you can calculator the pressure per turn the mechanism was under, and it’s not really able to be done easily.
The argument between the eminent Egyptologists that opens the article is frustratingly naive to anyone who has real experience in drilling and shaping hard materials. A dentist is, oddly enough, exactly the person I'd expect to write this article - academic enough to bother writing it, but practical enough to see the tool marks and have an insight into how they were made.
The whole thing reads like great literature. There should be a scientific magazine for papers that can be understood by the motivated layman. I accidentally read the whole thing in one sitting.
This is one of the most intriguing ancient mysteries, and is sufficiently well grounded in engineering practice that it can be experimentally validated. Things like the hardness of the cutting edge, the RPM required to mimic the drill markings, the shape and progression of the drill bit etc.
So, it's reasonably clear that the bronze-age Egyptians must have had some drilling rig for boring hard stone - one which operated at 1,000 rpm or similar and could make an impression into something like quartz. All the ancient aliens nonsense aside, this rig in itself must have been quite impressive in itself - probably a composite of pulleys and ropes with a tubular emery-embedded cutting bit. Would have loved to have seen it working!
If the claims of levitation, ultrasonic resonance, and/or lingam electrical plasma stone masonry methods are valid; perhaps the necessary RPMs for core drilling are lower than 1000 RPM.
Given drilled cores of e.g. (limestone, granite,), which are heavy cylinders that roll, when was the wheel invented in that time and place?
> The plasma treatment showed a maximum of 65% and a minimum of 15% reduction in specific cutting energy and was regarded as being dependent on mainly the hardness and size of the samples [and the electrical conductivity of the stone]
E.g. this video identifies electrodes and protrusions in various megalithic projects worldwide: https://youtu.be/n8hRsg8tWXg
Perhaps the redundant doors of the great pyramid were water locks rigged with ropes. There do appear to be inset places to place granite cores for rigging.
Ancient and modern stonemasonry skills; how many times have they been lost and why?
> (Note: Emery is a granular rock composed mainly of corundum—a crystalline compound of silicon and carbon—magnetite and spinel. Here, `emery’ and `corundum’ are used for the abrasive powders derived from these rocks.)
Corundum is Aluminium Oxide (not clear if this is part of the original article?)
For what seems like every 100 YouTube channels that speculate on everything from lost civilizations to aliens there are some mundane channels that actually set out to demonstrate and reproduce technologies and works like the ancients.
One of the more well known channels is scientists against myths, here is a link to one of their videos reproducing granite drill holes how the Egyptians might have: https://youtu.be/yyCc4iuMikQ?si=oUkmF122iHIklvuz
I really like their videos making granite and diorite vases, while the YT algo will tend to take you down the must have been lost technology/lost civilization/alien rabbit hole, sometimes you get lucky and they suggest other channels doing amazing work. The comments are fun too, no matter how well done anything is there’s always someone demanding demanding the small channels recreate the great pyramids at scale.
People want to believe in something more when it comes to ancient Egypt even if they know it is not reality. To me, it is obviously linked to the beauty and other worldly feel of the ancient Egyptian iconography and art.
If you just had the pyramids in the desert with the entire civilization lost, while impressive there wouldn't be other worldly explanations that sounded palatable. It would obviously just be the engineering of a lost civilization.
It is really a testament to the power of ancient Egyptian art that it can still inspire the imagination to such a degree thousands of years later and across cultures.
I'm getting a bit off topic here but regarding the pseudo-archaeology that's popular on YouTube: Graham Hancock (who had a 10 part Netflix series called Ancient Apocalypse about an advanced global civilization during/before the last glacial maximum) recently appeared on Joe Rogan's podcast alongside Flint Dibble who is an archaeologist that does public communication on YouTube.
At least according to my own YouTube bubble it seems we are in a pretty big moment for pseudo-archaeology! Here's an informal discussion about it from Stefan Milo who I highly recommend for anyone intereated in prehistory: https://youtu.be/rWugM4XRPuc?si=EkO5PEAKRAIYYRJD
I have seen another good quality video summarising the debate on the podcast but annoyingly I cannot remember it to share, maybe someone else can share a fun resource (unfortunately the Joe Rogan podcast is way too long for me to actually listen to)!
Are you saying there’s not ancient technology or civilization that’s lost to us? That seems extremely unlikely to me.
The name “scientists against myths” makes me wary of this channel. They clearly have an agenda, and I as a laymen have no way to identify when they’re letting that agenda cloud their judgment.
As a laymen I can at least evaluate the trustworthiness of other humans, and framing the debate as “science vs myth” when history is rife with examples of myths later being explained by science sets off alarm bells.
I think respecting the cutting depth per rotation would give better clues and would make the the assumption actually comparable to "what they did" back then
An initial undersized hole was drilled using any of the methods they suggest which produce no concentric rings. Then a single point boring tool was used to machine the hole to its final dimension. The hole tapers 1 cm over its length. 0.5 cm of wear of the single point tool in use would account for the decrease in diameter.
From the perspective of a person living in the US, it is technically correct that ancient aliens were responsible for all the ancient Egyptian artifacts.
They were ancient in that they lived a long time ago and they were aliens in that they were not citizens or residents of the US.
Probably with similar techniques. If you can spin a round thing against the same spot to make a hole you can certainly use the same materials and rub them in a straight line or along a curve. Hand woodworking involves painstakingly rubbing a little material off the work and then checking it, or shaving it off or cutting it off depending on where you are in the process. And you can also strike a soft metal against the stone to chip out a rough area before finishing and polishing. Inferior tools just have to be sharpened more often is all
If you're like me and want to some actual evidence,
here's a video where they scanned and uploaded STL files from pre-dynastic Egyptian vases.
https://youtu.be/QzFMDS6dkWU?feature=shared
This video is really frustrating. It spends the first 10 mintues trying to convince the viewer that these vases are not fake, yet has no evidence other than "There is no possible way these are fakes, just look at them!". Then he actively offers up that they have not performed this analysis on any museum piece vase which has been confirmed to come from an Egyption tomb or pyramid.
...so it wasn't ancient aliens, with laser-cutting and other amazing technology? That's disappointing. I mean, if I couldn't imagine how it possibly could've been done, then it had to be the aliens, right?
You snark, but please note the "[1983]" in the title. This article's points have since been expounded on, with new evidence both archaeological and experimental.
Namely:
> The concentric lines were not always perfectly parallel.
1. What the article calls "concentric circles" are, in fact, series of spirals. That is, a cutting point ploughing through the granite, round and round.
And indeed the fine abrasive circles that this article manages to reproduce (image 7b) look nothing like the original fairly well-spaced, deep-cut grooves of the original hole (image 1a, all the way at the top).
Petrie himself documented spiral grooves that span many drill rotations, sometimes totaling over 6 metres in a single continuous groove. This is well established and not disputed because the physical evidence is so plain.
Why the OP failed to mention spiral grooves and talks about "concentric circles" instead is unclear, given they otherwise quote Petrie extensively.
> [the hole] diameter on the outside is 5.3 cm. and tapers to 4.3 cm. on the inside.
> …a tubular copper drill creates a more parallel drill hole since it cannot wear beyond the internal diameter of the drill.
2. By all accounts, the tubular drills were fairly thin. We know this because there are thin (overdrilled) circles at the bottom of discovered tube holes, up to 0.5cm in thickness of the tube wall max. There you can see the actual narrow width of the tube because the bottom wasn't sawn off as in the case of OP's particular sarcophagus.
Again well documented by Petrie and others, supported by overwhelming physical evidence, so not a point of contention.
The OP does not go into how the observed difference of 1cm compares to the wear of the (presumably thinner) "internal diameter of the drill". See for example [0] for a clearer, updated exposition.
----
To be clear, none of this is of course evidence for any "aliens". But reading your snark reminded me of those internet fly-by experts who deride honest work of others because "The science is settled bro, I saw a documentary on NBC! Aliens lol these other people are cretins!"
I'd recommend turning off sound if Youtube amateur commentary irks you, but the breadth of physical evidence (photos and videos of actual stone artefacts, not theories around them) they display is astounding. Reading scientific papers (or watching NBC…) alone won't build you enough intuition and nuance for fly-by snarks. It is a complex topic, and not all amateurs are cretins. A bit of humility helps.
[+] [-] BostonFern|1 year ago|reply
The episode mainly explores the question of how an obelisk was raised. The team ran out of time before they were able to reach a satisfying conclusion, but they returned to Egypt in 1999 to record another NOVA episode, which includes two competing theories on how to raise an obelisk. I highly recommend both episodes.
https://www.pbs.org/wgbh/nova/lostempires/obelisk/cutting08....
https://youtu.be/qeS5lrmyD74
[+] [-] jstanley|1 year ago|reply
Anyone who has drilled brittle materials will know why the lines got closer together. The feed pressure was reduced near the end of the hole to avoid chipping out the back surface.
[+] [-] art3m|1 year ago|reply
https://www.youtube.com/watch?v=g305wqCdPRs (English subtitles included)
[+] [-] abj|1 year ago|reply
[+] [-] ArticlesGuitari|1 year ago|reply
Egyptians OR ancient aliens is a false dichotomy. There is a third option which funnily enough the egyptians themselves believed.
[+] [-] dhsysusbsjsi|1 year ago|reply
https://youtu.be/KFuf-gBuuno
[+] [-] Tor3|1 year ago|reply
[+] [-] et1337|1 year ago|reply
[+] [-] jdietrich|1 year ago|reply
[+] [-] trwm|1 year ago|reply
[+] [-] unwind|1 year ago|reply
1: https://en.m.wikipedia.org/wiki/Aptronym
[+] [-] Simon_ORourke|1 year ago|reply
So, it's reasonably clear that the bronze-age Egyptians must have had some drilling rig for boring hard stone - one which operated at 1,000 rpm or similar and could make an impression into something like quartz. All the ancient aliens nonsense aside, this rig in itself must have been quite impressive in itself - probably a composite of pulleys and ropes with a tubular emery-embedded cutting bit. Would have loved to have seen it working!
[+] [-] westurner|1 year ago|reply
Given drilled cores of e.g. (limestone, granite,), which are heavy cylinders that roll, when was the wheel invented in that time and place?
Wheel: https://en.wikipedia.org/wiki/Wheel
"Specific cutting energy reduction of granite using plasma treatment: A feasibility study for future geothermal drilling" https://www.sciencedirect.com/science/article/pii/S235197892... :
> The plasma treatment showed a maximum of 65% and a minimum of 15% reduction in specific cutting energy and was regarded as being dependent on mainly the hardness and size of the samples [and the electrical conductivity of the stone]
E.g. this video identifies electrodes and protrusions in various megalithic projects worldwide: https://youtu.be/n8hRsg8tWXg
Perhaps the redundant doors of the great pyramid were water locks rigged with ropes. There do appear to be inset places to place granite cores for rigging.
Ancient and modern stonemasonry skills; how many times have they been lost and why?
[+] [-] aixpert|1 year ago|reply
[+] [-] DoctorOetker|1 year ago|reply
Corundum is Aluminium Oxide (not clear if this is part of the original article?)
[+] [-] CapitalistCartr|1 year ago|reply
[+] [-] throwawaycities|1 year ago|reply
One of the more well known channels is scientists against myths, here is a link to one of their videos reproducing granite drill holes how the Egyptians might have: https://youtu.be/yyCc4iuMikQ?si=oUkmF122iHIklvuz
I really like their videos making granite and diorite vases, while the YT algo will tend to take you down the must have been lost technology/lost civilization/alien rabbit hole, sometimes you get lucky and they suggest other channels doing amazing work. The comments are fun too, no matter how well done anything is there’s always someone demanding demanding the small channels recreate the great pyramids at scale.
[+] [-] borgdefense|1 year ago|reply
If you just had the pyramids in the desert with the entire civilization lost, while impressive there wouldn't be other worldly explanations that sounded palatable. It would obviously just be the engineering of a lost civilization.
It is really a testament to the power of ancient Egyptian art that it can still inspire the imagination to such a degree thousands of years later and across cultures.
[+] [-] bjackman|1 year ago|reply
At least according to my own YouTube bubble it seems we are in a pretty big moment for pseudo-archaeology! Here's an informal discussion about it from Stefan Milo who I highly recommend for anyone intereated in prehistory: https://youtu.be/rWugM4XRPuc?si=EkO5PEAKRAIYYRJD
I have seen another good quality video summarising the debate on the podcast but annoyingly I cannot remember it to share, maybe someone else can share a fun resource (unfortunately the Joe Rogan podcast is way too long for me to actually listen to)!
[+] [-] fififbaajdjd|1 year ago|reply
Are you saying there’s not ancient technology or civilization that’s lost to us? That seems extremely unlikely to me.
The name “scientists against myths” makes me wary of this channel. They clearly have an agenda, and I as a laymen have no way to identify when they’re letting that agenda cloud their judgment.
As a laymen I can at least evaluate the trustworthiness of other humans, and framing the debate as “science vs myth” when history is rife with examples of myths later being explained by science sets off alarm bells.
[+] [-] Nykon|1 year ago|reply
[+] [-] unknown|1 year ago|reply
[deleted]
[+] [-] mhb|1 year ago|reply
An initial undersized hole was drilled using any of the methods they suggest which produce no concentric rings. Then a single point boring tool was used to machine the hole to its final dimension. The hole tapers 1 cm over its length. 0.5 cm of wear of the single point tool in use would account for the decrease in diameter.
[+] [-] RcouF1uZ4gsC|1 year ago|reply
They were ancient in that they lived a long time ago and they were aliens in that they were not citizens or residents of the US.
So yes, ancient aliens built the pyramids.
[+] [-] amai|1 year ago|reply
[+] [-] throwaway173738|1 year ago|reply
[+] [-] chris_st|1 year ago|reply
[+] [-] abj|1 year ago|reply
[+] [-] alt227|1 year ago|reply
[+] [-] skiter|1 year ago|reply
[deleted]
[+] [-] Joker_vD|1 year ago|reply
[+] [-] peutetre|1 year ago|reply
That sounds right.
I couldn't imagine how Indiana Jones 4 could possibly be such a bad movie. It turned out to be aliens.
[+] [-] ganzuul|1 year ago|reply
[+] [-] Radim|1 year ago|reply
Namely:
> The concentric lines were not always perfectly parallel.
1. What the article calls "concentric circles" are, in fact, series of spirals. That is, a cutting point ploughing through the granite, round and round.
And indeed the fine abrasive circles that this article manages to reproduce (image 7b) look nothing like the original fairly well-spaced, deep-cut grooves of the original hole (image 1a, all the way at the top).
Petrie himself documented spiral grooves that span many drill rotations, sometimes totaling over 6 metres in a single continuous groove. This is well established and not disputed because the physical evidence is so plain.
Why the OP failed to mention spiral grooves and talks about "concentric circles" instead is unclear, given they otherwise quote Petrie extensively.
> [the hole] diameter on the outside is 5.3 cm. and tapers to 4.3 cm. on the inside.
> …a tubular copper drill creates a more parallel drill hole since it cannot wear beyond the internal diameter of the drill.
2. By all accounts, the tubular drills were fairly thin. We know this because there are thin (overdrilled) circles at the bottom of discovered tube holes, up to 0.5cm in thickness of the tube wall max. There you can see the actual narrow width of the tube because the bottom wasn't sawn off as in the case of OP's particular sarcophagus.
Again well documented by Petrie and others, supported by overwhelming physical evidence, so not a point of contention.
The OP does not go into how the observed difference of 1cm compares to the wear of the (presumably thinner) "internal diameter of the drill". See for example [0] for a clearer, updated exposition.
----
To be clear, none of this is of course evidence for any "aliens". But reading your snark reminded me of those internet fly-by experts who deride honest work of others because "The science is settled bro, I saw a documentary on NBC! Aliens lol these other people are cretins!"
I'd recommend turning off sound if Youtube amateur commentary irks you, but the breadth of physical evidence (photos and videos of actual stone artefacts, not theories around them) they display is astounding. Reading scientific papers (or watching NBC…) alone won't build you enough intuition and nuance for fly-by snarks. It is a complex topic, and not all amateurs are cretins. A bit of humility helps.
[0] https://antropogenez.ru/drilling/
[+] [-] unknown|1 year ago|reply
[deleted]
[+] [-] colibri727|1 year ago|reply
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