London, May 2:
It is time to rewrite history books. The mystery of how Egyptians moved huge stones to build pyramids has been unlocked, finally.
According to a path-breaking research, the ancient Egyptians may have been able to move massive stone blocks by wetting the sand in front of a contraption built to pull the heavy objects.
Adding water to the sand increased its stiffness and the sleds were able to glide more easily across the surface.
This is because droplets of water create bridges between the grains of sand, which helps them stick together, researchers noted.
“It is also the same reason why using wet sand to build a sandcastle is easier than using dry sand,” said lead author Daniel Bonn, a physics professor at University of Amsterdam.
To reach this conclusion, Bonn and his team constructed miniature sleds and experimented with pulling heavy objects through trays of sand.
They dragged the sleds over dry sand and noticed clumps would build up in front of the contraptions, requiring more force to pull them across.
They discovered that dampening the sand in front of the primitive device reduces friction on the sled, making it easier to operate.
But according to the researchers, the challenge was to get the right stiffness as either too dry or too wet sand would not work so the amount of water necessary depended on the type of sand.
The findings appeared in the journal Physical Review Letters.