Water used to build Egyptian pyramids?

By Melissa Platero, CCNN Writer

pyramid building
The miniature recreation of pulling heavy objects across moistened sand shows how much less force is required with just a bit of water added.

The mega pyramids in Egypt, which date back to thousands of years ago, have always confused scientists. How did the ancient Egyptians manage to haul so many heavy stones into place, without modern technology? While theories range from “aliens did it” to thousands of slaves pulling huge rocks, a recent study shows that water may have been used to make the sand slicker.

See, if you make sand just wet enough to be slippery, it can reduce the amount of force needed to pull an object across it by half. So, scientists set up a test where they measured the amount of yanking required for pulling a sledge across a tray of sand. Sure enough, if the correct quantity of water was applied, it was much easier!

Besides, there’s a painting that supports the theory as well. In the tomb of the ancient Egyptian ruler Djehutihotep (try saying that 3 times fast), dozens of Egyptians are shown pulling a sledge with a huge statue on top, while a guy at the front of the line pours a bucket of water on the ground!

Image of sledge experiment courtesy of Foundation for Fundamental Research on Matter.