Co.Design

A New Theory On How Ancient Egyptians Built The Pyramids

Workers probably used moistened sand to transport massive stones, according to new research.

How ancient Egyptians constructed the pyramids is still somewhat of an archeological mystery. Everything from cranes and ramps to oil-slicked slipways to aliens (naturally) have been put forward as possible mechanisms. A group of Dutch physicists has a new hypothesis on how ancient Egyptians managed to drag the colossal stones necessary to build pyramids across the desert. The answer: wet sand.

The setup in the labPhysical Review Letters

In a study in the journal Physical Review Letters, researchers from the University of Amsterdam and FOM (the Foundation for Fundamental Research on Matter) recreated a laboratory version of the sledge on which workers hauled heavy stone, and tested how it fared in sand. They found that pulling the sledge across damp sand requires only half the force of hauling it in dry sand. Because the water droplets bind the grains of sand together, wet sand is twice as stiff as dry sand, and doesn't pile up in front of the sledge as it moves along. (A good tip for sandcastle construction, too.)

Wall painting from the tomb of DjehutihotepPhysical Review Letters

The researchers bolstered their theory with a wall painting from around 1880 B.C. found in the tomb of a 12th-dynasty administrator named Djehutihotep, which shows what looks to be a worker pouring water in front of a sledge carrying a large statue.

[H/T: Phys.org]

[Image: The pyramids at Giza near Cairo, Egypt via Dan Breckwoldt / Shutterstock]

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48 Comments

  • moonstruck

    Poop. Cheap and greasy and easy to leave behind contributed by slaves poorly fed to a condition of diarhea.

  • I think it was not water but oil poured into the sand it would not evaporate and the path could be seen and used more frequently, if their were a way to test the sand for olive oil or some other oil from the ancient path it could explain my theory oil not water to move the massive blocks and statues the viscosity of oil would make it easier to move an object than water. Tom H. DeSimone

  • Harry McNicholas

    Never spent any time on the beach have you Tom? You have a hard time running in dry sand. In sand too wet, you sink. However, just between the both you can run and even drive your car. Oil would glue together and not spread out enough. It would also dry and harden on the rails of the sled complete with pieces of sand.

  • Robert Calfee

    I think the pyramids were made by binding local sand with something that is the same as what holds sandstone together, and poured in place with simple formwork. That would make it easy to do a lot of blocks in one day, and would explain the good fit.

  • Harry McNicholas

    Sorry the blocks on the outside of the pyramids are limestone cut from a nearby quarry. Inside around the burial chamber they are granite hauled by boat on the nile many miles distant.

  • Jimmy White

    Archeologists get things so wrong mainly because they (we) assume, that ancient peoples were far more stupider than we are. I'd believe that ET built the pyramids IF they were constructed of a single piece of granite. (yeah, they crossed interstellar space to stack up a bunch of rocks) A million people with mathematical knowledge, all believing in their minds and hearts that they'd all die if they didn't build a pyramid, would get the job done in short order. Belief is a powerful motivator. Egypt wasn't always a desert and elephants can move mountains. Oil and sand or, beeswax and sand is recyclable - shovel it up, heat it up remove excess sand and transport it where ya need it,- in woven baskets.. er.. clay vessels.

  • Harry McNicholas

    Sorry but when the pyramids were built, Egypt was a desert and there is nothing to indicate they ever attempted to use elephants.

  • Harry McNicholas

    Sorry but when the pyramids were built, Egypt was a desert and there is nothing to indicate they ever attempted to use elephants.

  • Harry McNicholas

    Sorry but when the pyramids were built, Egypt was a desert and there is nothing to indicate they ever attempted to use elephants.

  • Harry McNicholas

    Sorry but when the pyramids were built, Egypt was a desert and there is nothing to indicate they ever attempted to use elephants.

  • Harry McNicholas

    Sorry but when the pyramids were built, Egypt was a desert and there is nothing to indicate they ever attempted to use elephants.

  • Harry McNicholas

    Sorry but when the pyramids were built, Egypt was a desert and there is nothing to indicate they ever attempted to use elephants.

  • Harry McNicholas

    Sorry but when the pyramids were built, Egypt was a desert and there is nothing to indicate they ever attempted to use elephants.

  • The wet sand theory may help explain how they dragged large stones and objects to the pyramid site, maybe not. One thing they did not do is put a flat object or slab on the sand and drag it. This would put to much surface area on the sand. They used a sled, with runners on each side, and the center raised from the ground. This way, they would not need as much water in front of the skids to solidify the sand. I see in the illustration others also carrying jugs of presumably water to give to the one standing and pouring water in front of the skid. This also does not look like a large amount of water was used, but a lot of man power was. I doubt they used oil, it would have made a real mess later, and oil is too valuable to waste pouring on sand. However, once they got to the site, how did they get the stones to the upper levels? No one knows. We need another illustration for that!

  • Harry McNicholas

    For the lower heavier stones which could weigh up to 60 tons, they used ramps. Higher up smaller stones were used. To lift those stones they used a common Egyptian pulley with a 10:1 ratio. They would make rope baskets which would be filled with bags of sands. One part of the pulley was tied to a stone and the other to the baskets. You would only need say 400 lbs. of sand to lift 4,000 lb stone. The reality is though nobody knows since the Egyptians did not write how they built the pyramids.

  • The wet sand theory may help explain how they dragged large stones and objects to the pyramid site, maybe not. One thing they did not do is put a flat object or slab on the sand and drag it. This would put to much surface area on the sand. They used a sled, with runners on each side, and the center raised from the ground. This way, they would not need as much water in front of the skids to solidify the sand. I see in the illustration others also carrying jugs of presumably water to give to the one standing and pouring water in front of the skid. This also does not look like a large amount of water was used, but a lot of man power was. However, once they got to the site, how did they get the stones to the upper levels? No one knows. We need another illustration for that!

  • John Muir

    It has been long known, that they used Taro, as a lubricant, and other oils. That would have the same effect and not evaporate as quickly. It doesn't of course address how they got the stones on the sledges, and how they were able to assemble so many blocks in each day. That, I'm sure can be solved on another day, with other evidence that is known. It is through experimentation, that these methods will be unveiled, not speculation or wild imagination. I will also point out, that sledge methods have shown, that even a one ton block can and has been moved, over level ground, by only one man! More study is needed of course, and as we learn more, it will become more clear, just how people, from 4,000 years ago, can and did build these monuments.

  • J.b. Stringfellow

    How about using a more viscous fluid than water? The water in the pic appears dark. I'm not an engineer so I have no idea.