Monday, May 19, 2014
Egyptian Secret to Moving Huge Pyramid Stones
This is not the whole story of course but it is certainly part of the story and a very important part. It allows a sand roadbed to be constructed from the block making locale to the pyramid for direct haulage in order for the blocks to be stockpiled in preparation for construction. I had anticipated a canal, but this would work quite as well. One can even grade the sand to optimize its effectiveness as well.
In this way a sledge of blocks may even be sped steadily across the desert without let up.
We have perhaps all seen that particular image as well and never grasped its significance. Asking the right question has revealed an answer.
An important question will be to discover what grades may be possible and whether runners can be accommodated also. This promises to greatly facilitate the use of ramps in the early levels of building although doing nothing after that limit is reached.
Scientists Discovered the Egyptian Secret to Moving Huge Pyramid Stones
The question of just how an ancient civilization—without the help of modern technology—moved the 2.5 ton stones that made up their famed pyramids has long plagued Egyptologists and mechanical engineers alike. But now, a team from the University of Amsterdam believes they've figured it out, even though the solution was staring them in the face all along.
It all comes down to friction. See, the ancient Egyptians would transport their rocky cargo across the desert sands, from quarry to monument site with large sleds. Pretty basic sleds, basically just large slabs with upturned edges. Now, when you try to pull a large slab with upturned edges carrying a 2.5 ton load, it tends to dig into the sand ahead of it, building up a sand berm that must then be regularly cleared before it can become an even bigger obstacle.
Wet sand, however, doesn't do this. In sand with just the right amount of dampness, capillary bridges—essentially microdroplets of water that bind grains of sand to one another through capillary action—form across the grains, which doubles the material's relative stiffness. This prevents the sand from berming in front of the sled and cuts the force required to drag the sled in half. In half.
As a UvA press release explains,
The physicists placed a laboratory version of the Egyptian sledge in a tray of sand. They determined both the required pulling force and the stiffness of the sand as a function of the quantity of water in the sand. To determine the stiffness they used a rheometer, which shows how much force is needed to deform a certain volume of sand.
Experiments revealed that the required pulling force decreased proportional to the stiffness of the sand...A sledge glides far more easily over firm desert sand simply because the sand does not pile up in front of the sledge as it does in the case of dry sand.
These experiments served to confirm what the Egyptians clearly already knew, and what we probably already should have. Artwork within the tomb of Djehutihotep, which was discovered in the Victorian Era, depicts a scene of slaves hauling a colossal statue of the Middle Kingdom ruler and in it, a guy at the front of the sled is shown pouring liquid into the sand. You can see it in the image above, just to the right of the statue's foot.
We can now finally put this scientific snipe hunt to rest and focus on how the hell Stonehenge got that way. [Gizmodo en Español]