"[A team of eight researchers led by Daniel Bonn] placed a laboratory version of an Egyptian sledge in a bin of sand that had been dried in the oven. Then they threw down some water, and measured the grains’ stiffness."
Surely the way to test this theory isn't to make a model of a sledge, and bake some wet sand in an oven in your lab in Amsterdam! Go to Cairo, build a wooden sledge, get some water and fifty men for an hour and see whether one can sledge two tons across wet sand. I quite fancy testing it out myself. Perhaps I could run a Kickstarter to build a pyramid.
NOVA on PBS pulled a "Mythbusters" in the 1990s and made attempts to raise an obelisk using only technology & techniques conceivably available at the time:
The picture is quite convincing indeed... once I was biased by the explanation!
For those of you that haven't read the article yet, I suggest you study the picture with the hieroglyphics in detail first and then read the conclusion!
Edit:
Just to be clear, I wanted others to have the benefit of seeing the picture before the explanation, because after the fact I had no idea whether I had been biased by what I had read first! I wasn't trying to suggest it was biased per se! I have no idea whether I was biased or not. I can't undo history.
OK, I did that. Still haven't read the article yet, actually. It looks like a statue on sled with a guy pouring something out in front of it. And having now read the article, it appears that's exactly the same conclusion it reaches.
I think it's quite convincing once you know the scientific fact that dragging an object requires half the work on wet sand. What's the alternative: that the Egyptians did at some point drag objects on wet sand, but that they didn't know it made things easier? Wouldn't they immediately learn that the first time they tried it, even if they first tried it for a different reason?
I love seeing how clever people figure out ways to solve problems with the tools they have. Also good to remember hacking didn't start with and doesn't only apply to computers.
If the water had the appropriate level of wetness, something called “capillary bridges” — extremely small droplets of water that glue together individual grains of sand — would form.
I wonder what happened when the water wasn't wet enough.
I like this part, in reference to a painting that shows water being poured on the sand in front of a sled:
>“In fact, Egyptologists had been interpreting the water as part of a purification ritual, and had never sought a scientific explanation. And friction is a terribly complicated problem; even if you realize that wet sand is harder – as in a sandcastle, you cannot build on dry sand — the consequences of that for friction are hard to predict.”
Makes me wonder what other practical things we might be misinterpreting as rituals. Are we constantly ignoring ancient cultures' innovations because we assume they have no practical purpose?
That's a terrible summary; even the strong proponent of the Egyptian concrete theory quoted in the article suggests 10-20% of the blocks were cast of a synthetic material.
That means that there's still reason to go looking for the method of transport for the other 80-90% of the blocks.
OK, but how did they move the water? I can't load the Uni page to see how much water was needed but if we're talking miles or tens of miles, we should be talking about a lot of water. Water that dries very quickly so the path has to be wet again for the next load.
I think that egyptians had access to irrigation technology. And from what I remember as a kid on the beach you don't need that much water - you only need to create a film.
A few ways come to mind - a channel from nile parallel to the hauling route. On the barge itself.
Although I would have used combination of highly polished wood, leather/hides on wood planks and cooking oil. And crews that just take the back pieces and move them in front.
[+] [-] AlexMuir|12 years ago|reply
Surely the way to test this theory isn't to make a model of a sledge, and bake some wet sand in an oven in your lab in Amsterdam! Go to Cairo, build a wooden sledge, get some water and fifty men for an hour and see whether one can sledge two tons across wet sand. I quite fancy testing it out myself. Perhaps I could run a Kickstarter to build a pyramid.
[+] [-] DanBC|12 years ago|reply
Egypt today is probably quite different to the Egypt of 4,500 years ago. Would that influence the experiement at all?
[+] [-] Wingman4l7|12 years ago|reply
http://www.pbs.org/wgbh/nova/egypt/raising/
http://www.pbs.org/wgbh/nova/lostempires/obelisk/raises.html
[+] [-] afarrell|12 years ago|reply
[+] [-] junto|12 years ago|reply
For those of you that haven't read the article yet, I suggest you study the picture with the hieroglyphics in detail first and then read the conclusion!
Edit:
Just to be clear, I wanted others to have the benefit of seeing the picture before the explanation, because after the fact I had no idea whether I had been biased by what I had read first! I wasn't trying to suggest it was biased per se! I have no idea whether I was biased or not. I can't undo history.
[+] [-] chc|12 years ago|reply
[+] [-] eurleif|12 years ago|reply
[+] [-] kabdib|12 years ago|reply
"Ancient engineers used text editors to write machine language."
"But how did they construct network packets?"
"With Emacs macros. And purification rituals involving Python."
"No way. It had to have been aliens."
[+] [-] te_platt|12 years ago|reply
[+] [-] whoismua|12 years ago|reply
[+] [-] amalag|12 years ago|reply
A new theory says wet sand was used to build the pyramids. But where did the aliens get all that wet sand???
[+] [-] maw|12 years ago|reply
I wonder what happened when the water wasn't wet enough.
[+] [-] eurleif|12 years ago|reply
>“In fact, Egyptologists had been interpreting the water as part of a purification ritual, and had never sought a scientific explanation. And friction is a terribly complicated problem; even if you realize that wet sand is harder – as in a sandcastle, you cannot build on dry sand — the consequences of that for friction are hard to predict.”
Makes me wonder what other practical things we might be misinterpreting as rituals. Are we constantly ignoring ancient cultures' innovations because we assume they have no practical purpose?
[+] [-] alex_doom|12 years ago|reply
[+] [-] aspidistra|12 years ago|reply
[+] [-] unknown|12 years ago|reply
[deleted]
[+] [-] bri3d|12 years ago|reply
That means that there's still reason to go looking for the method of transport for the other 80-90% of the blocks.
[+] [-] zyxley|12 years ago|reply
Wheelwrights hate him! Use this one weird old trick to make your pyramid bigger!
[+] [-] mrbill|12 years ago|reply
[+] [-] whoismua|12 years ago|reply
[+] [-] thornofmight|12 years ago|reply
They could probably load up an empty sleigh with water and then drag it to the rocks.
[+] [-] venomsnake|12 years ago|reply
A few ways come to mind - a channel from nile parallel to the hauling route. On the barge itself.
Although I would have used combination of highly polished wood, leather/hides on wood planks and cooking oil. And crews that just take the back pieces and move them in front.