The Secret to Building the Pyramids? Wet Sand

By Carl Engelking | May 1, 2014 3:06 pm

pyramids

The Egyptian pyramids are considered one of the Seven Wonders of the World, and it’s not surprising: when you stare at the massive structures, you can’t help but wonder, “How the hell did they do it?” The stones, some weighing 9,000 pounds, came from far away and needed to be dragged into place. Now, researchers from the University of Amsterdam believe they’ve discovered ancient Egyptians’ cunning strategy to move those massive stones: wet sand.

With the right amount of water, researchers found, sand turns into a sturdy surface that halves the force needed to drag sleds loaded with rocks or statues across the desert. In fact, an ancient wall painting in the tomb of Djehutihotep shows a person pouring water over the sand in front of a sledge. 

Sliding Sleds

Sand builds up in front of the sledge when it is dragged over dry sand. On the wet, compact sand this does not occur. (Credit: Fundamental Research on Matter)

Sand builds up in front of the sledge when it is dragged over dry sand. On the wet, compact sand this does not occur. (Credit: Fundamental Research on Matter)

To test their hypothesis, researchers loaded up sledges with heavy weights and, well, dragged them across sand. When they dragged the weighted sled across dry sand, the front of the sled dug into the sand and nosedived deeper into trouble. When the sand was wet, however, the sand stiffened and allowed the sled to slide across with ease. At a molecular level, that’s because so-called capillary bridges arise when water is added to sand, which binds the sand grains together.

Researchers then used a rheometer to measure how much force is needed to deform a certain volume of sand. They found that wet sand is about twice as stiff as dry sand, which, in turn, halves the amount of force needed to move a weight. They published their findings Tuesday in the journal Physical Review Letters.

The simple wetting of sand, then, may have made building the pyramids easier—though the 100,000 slaves (according to Greek historian Herodotus) who labored constantly to build the massive structures may debate that definition of easy.

 

Photo credit: abc7/Shutterstock

CATEGORIZED UNDER: Living World, top posts
MORE ABOUT: archaeology, physics
  • abdess

    i kinda liked the alien theory, too bad!

    • BoostedSRT

      oh don’t worry the state of Egypt is still narrow minded and out right lying about the Sphinx…which was eroded by water.

      • Me

        so does it even rain in the desert? No, it dosnt.. so in theory when the pyramids were built there was no wet sand, there must have been green grass and trees along the nile, built right next to the pyramids.30,000bc

        • neeti vidyarthi

          Pyramids were not built around 4000 years back as was earlier belief but around 10500 or 11000 years back as it is proven now according to some researchers that Giza was built in the constellation of leo and it is mirror image of orion constellation on Earth. And this exact allignment took place 10500 years back and that time that area was green land and also some kind of flooding took place as there are signs of water erosion found there. It became a desert much later due to climate osilation a factor depending on pole shift due to precession of Equinox.

        • Jos Reyn

          Ever hear of carting water around?

        • Will

          Erm, actually it does rain in the desert. I should know, I live in one.

  • http://againstjebelallawz.wordpress.com/ Enopoletus Harding

    The pyramids weren’t built by 100 thousand permanent slaves, but by less than 30 thousand temporary conscripts.

  • Miles Archer

    So the Egyptians also discovered capitalism?

    • http://www.theclassicalliberal.com The Classical Liberal

      A conscript equals capitalism to you?

  • Tova Rischi

    The builders left all kinds of graffiti in the pyramids as they built them; they weren’t as uneducated as a slave would have been. Likewise there’s still the remains of the camps the men who built them stayed at, even with some contemporary (unlike Herodotus) documentation of what went on.

    Funny thing, the pyramid creators seemed to have leagues of builders united in common interest to prevent extreme abuses and negotiate pay; in other words, the first documented labor unions.

    • DS

      There is no graffiti in the great pyramid.

  • rogerklein

    the pyramids were built out of a form of limestone concrete

  • Gasser Mamdouh

    The pyramids weren’t built by slaves

  • http://organtitus.tumblr.com/ Organtitus Aurealialous

    They failed to mention that they also got help from aliens.

    • Ismael

      They also used jeeten’s self-inflating pomposity to lift up the stones so they could slide them into place.

  • Mónica Elisabeth Sacco

    Oh,come on! Not a single slave worked at the pyramids! Actually, pyramids are one of the very first examples of public work! Free masons and other workers laboured at the buildings, with medical facilities and even a cimitery! Nobody would care so much about slaves as to give them a cimitery. Please stop spreading such kind of nonsense . Anyway, the theory of wet sand goes along very well.

    • Bill

      Monica please? Slaves were used to do all manual labor in Egypt. The Egyptians had slaves, they speak openly about them. If there was work to be done, I’m sure slaves were used to do it, even if they may have also used paid labor. Give a man a choice to use his free, slave labor, or pay a freeman to do the work, what do you think he’ll do?
      You pay people to do what your free labor slaves can’t.
      Just look to any slave owning society, where do you see freemen working in the cottton fields of the slave south?
      Slaves in the south became very well skilled at many tasks that needed to be done from carpentry to metalwork.

      It is a faulshood that the slaves were untrained and stupid, only used for simple manual labor.
      In several letters written by Thom. Jefferson (3rd Pres. of the U.S.), he openly prases the skills of his slaves, and the impressive quality of their work, which was making him rich by selling the goods to other landowners and businesses.

      Slaves were taught to do everything that needed to be done on the plantation.
      People had slaves because they had work for the slaves to do, simple. Slaves are only valuable if they can do work. If they can’t do work then there is no point in having slaves, after all, you have to feed them, and that costs money

      • David Bacote

        As a matter of fact free laborers often worked as cotton pickers in the south, both whites and free blacks.
        Slaves are often highly skilled in the south US slaves were carpenters metal workers livestock trainers irrigation engineers accountants you name it.The earliest Africans brought to the Americas were brought for their agricultural expertise.
        The is most likely true of most societies.

      • DS

        Slaves did not perform skilled labor. Sorry.

        • Joe Dailey

          why you can be skilled and have your right taken from you?

        • Soothsayer

          And you were there right? Just because your ancestors weren’t skilled slaves and were tossed to the dogs doesn’t mean all slaves weren’t skilled. In fact skilled slaves were prized. More valuable in the slave trade. After all, who wants a dumb slave that can’t even cook or build you a simple shed? Who do you think built all those little houses where they lived!? Who took care of the animals? Who dressed their masters and did their hair? Who made all those metal tools for the farm? All slaves learned a skill trade, be it carpentry, blacksmith, livestock trainers, house maids to tend to the misses needs, engineers to build stuff(I.e buildings, bridges, water irrigation systems for farming). Ect.. There were even some slave who were thought to read and write so they can write documents for their masters. Some even helped in accounting affairs keeping the books, counting money, check writing, ect..(a rare thing, but it existed). I can go on and on.

      • Andrew

        As its been through out most of history, people didn’t work to get “paid” with cash(tender). But worked to contribute, and paid for goods in kind(trade). The pyramids weren’t built by slaves. They were built by people devoting their lives to someone they thought was a god on earth. That’s pretty established. Anyone who told you otherwise was just spewing nonsense.

    • Me

      Bill is an idiot Monica. The pyramids were built close by the nile river, the nile river doesn’t have sand around it now, could it even be possible if all the way back then they didnt even build in a desert. That it was planned and alinged in a live environment, green grass, green trees, water, all kinds of animals. They lived in the Animal Kingdom, not in a desert! so shove that wet sand up your va J J, this article is going around the internet like crazy.

  • Bill

    This is so stupid.
    In a country that lacks large bodies of clean water they are going to waist hundreds of millions of gallons of water!
    How did they get the water inot the desert to wet the sand? And since it is very hot, and water evaperates quickly, how are they going to stop the sand from drying out… in the desert?
    Didn’t someone tell these people Egypt is largely desert? It is near teh equator, it is very hot there.
    The Egyptians tied a wheel frame around the square block.
    The rock became the hub of the wheel, with wooden wheel around it. then they rolled it in place.
    To go up hill, they wrapped rope around the wheel and then used the rope to pull the block up hill. Using mechanical advantage to move the large weight up hill.
    The Egyptians wern’t stupid, they had the wheel. Chariots, ever heard of them. They had wheels. They turned the block of stone into a wheel.
    Simple solution, to a simple problem.

    • lesley.cluffXxplornet.ca

      yup – heard this method was realized from the discovery of a toy version of the pieces that when tied around the rock, turned it into a big wheel! But wheels don’t do well in sand, so I can see the combination of wheel and the water on sand thing – cost was not a consideration when building the pyramids. If they could handle rocks weighing several tons, they could deal with getting enough water to the site. But the means may be long gone.

    • Matt

      Aren’t the Great Pyramids of Giza only a few miles from the Nile River?

      • Vladislaw

        Yes and the nile has shifted.

    • Vladislaw

      by using canals to bring the water from the nile.. the nile has sifted in the last 4000 years, satellite images have proven that.

    • Elias Demetriou

      The Egyptians didn’t have chariots until after the Hyksos invasion (18th cen. B.C.) when they copied them after seeing the Hyksos horse drawn chariots.

  • tfosorcim

    OF COURSE! This explains all those teeny, tiny sheds made of brass rods, in the vslley of the Kings; temporary housing for the elite workers.
    Then, when the job was finished, those crafty Egyptians used the brass material to start the Bronze Age and invent brass bands so that The Music Man could be created.
    Aliens! Paahhh!

  • Hermev

    Antes de opinar, deben leer la historia de Egipto , conocer su geografia y su dependencia del rio Nilo.

  • aaqib

    Dumb reasoning/explanation ever given by anyone. Deserts have scarcity of water, then how were they able to wet miles and miles in those deserts? Grow up!

    • Vladislaw

      they could bring water from the Nile with the causeway canals leading to the nile river.
      The nile, like any river, changes course and moves around. The nile is now farther away then it was in 2500 bc.

    • Guest

      You could just bring the blocks by boat down the nile and raft them up the causeway and then sled them over wet sand.

    • Vladislaw

      boat the blocks down the nile,raft them up the causeway and sled them on wet sand

      • Guest

        So…
        HOW did the use this novel “scientific principle”
        TO STACK and ALIGN these MASSIVE BLOCKS in such PRECISION?
        I’m calling this “theory” complete B.S.

      • donaldinks

        So…
        HOW did they use this novel “scientific principle”
        TO STACK and ALIGN these MASSIVE BLOCKS in such PRECISION?
        I’m calling this “theory” complete B.S.

        • Vladislaw

          Which precision are you refering to?

          • donaldinks

            The outer mantle was composed of
            144,000 casing stones, all of them highly polished and flat to an
            accuracy of 1/100th of an inch, about 100 inches thick and
            weighing approx. 15 tons each.

            THAT is how “precice”.

          • Vladislaw

            actually.. that is not quite true .. do your due dilligence.

          • donaldinks

            “do your due *dilligence”

            Do YOUR OWN due *DILIGENCE!

            You put up photos, of what the pyramids look like TODAY after they have been weathered by nature since (supposedly) 2589 and 2504 BC…
            and LONG AFTER the casing stones were stripped away:

            and NOW question the acute and precise workmanship when they were NEW?
            smh….

          • Vladislaw

            actually STAND on them .. then make your mind up .. actually work with stone .. then make your mind up .. talk to actual stone workers then make your mind up…

          • Otis Melius

            Yes, compared to Khazad-dûm this is shoddy stonework (though I understand a remnant of the dwarves passed through ancient Egypt and were consulted in their building).

          • Vladislaw

            please point to the post I made where I called the egyptian stonework “shoddy” ?
            I took issue with stating EVERYTHING pyramid is “precision” .. clearly, like in modern stone work. margins are lower where the stone work is either not seen, or non load bearing.

          • Soothsayer

            And lastly, you weren’t there thousands of years to see how good they were fitted together. All we see now is a weathered stone. But go inside the pyramid and you’ll see good samples of how nicely fitted they are then picture that 5000 years ago when it was a smooth brand new polished stone. Your modern stone work doesn’t compare to the ancients. So much knowledge was lost, we are now just beginning to rediscover it, and yet, look at this example, no one can even figure out how it was built for sure without a doubt. Also check out South american in Peru how their stone work comes together nicely high up in the peeks of mountains, another marvel of ancient engineering. Its so mind blowing that some people will come to the conclusion that aliens must have played a part in it.

          • Vladislaw

            Labor would not be wasted on turning “filler” stones into freakin’ works of art.

        • Vladislaw

          Does not look that precise to me.

          • Soothsayer

            That’s what it looks like after 5000 years of weathering and pillaging. When first built, they were beautifully precisely fitted, also there was a smotth polished white casing cover stone that went on top of that too that made the sides smooth like a slide instead of what we see now with these step looking structure.

  • Syed Ashar Ali

    Ok sliding on the ground is understandable, But how about lifting up on top ?

    • Geoff Mather

      Pulleys. They had a central shaft with a large stone as a counterweight.

      • jeeten

        then how do they raise the counterweight?

        • jhernandez1981

          Tons of people

          • jeeten

            how to they raise the other counterweight which raises the counterweight which raises the block?yet another another another counter counter counter weight?

          • jhernandez1981

            i was joking around, but its pretty obvious how they would have elevated the counter weight initially – they had ramps, pulleys, massive man power, and more than a basic understanding of engineering.
            Its not that difficult.

          • jeeten

            nope. what you are describing is not logical.
            COunterweights have to be countered by other counterweights when the load is taken off the derrick.Try to imagine raising bricks with the use of a counterweight on a house constrcution derrick.ONly pumped fluid on reservoir counterweights allow such a thing.

          • jhernandez1981

            i dont think you know what logic is. A counter weight just needs the weight (even in its most primitive state this system was adjustable), a pivot point, and leverage. You dont need a counterweight for the counterweight. Thats absurd.

          • jeeten

            lol…abbhorrent dickhead….when the load is removed the counterweight will swing your crane mechanism to a aposition that you will need some way of lowering it,and is more complex than raising the stone directly . FOr your info,if you choose to understand it and not be a 13 yr old arguement prick,i build software that analyses steel structures with artificial intelligence.But of course, you will ramble on and on…..suit yourself…you already lost all credibility.

          • jhernandez1981

            I dont know why this thing deleated my previous reply but once again: you might be a programmer but you’re definitely not an engineer. You should look up a device called a shadoof. Its an ancient Egyptian counterweight device primarily used for moving water for irrigation, but can be easily scaled up for heavier duty like moving stones. It is literally just a pivot point, a long pole for leverage and a counterweight and believed by a great number of respected archaeologists and engineers to be the tool they used to set the stones.

          • jeeten

            BEfore i continue with you: answer this, what can the determinant of matrix teach us about a frame?I want to know who i am dealing with here.
            If you can answer this satisfactorily, maybe you do know some engineering.

          • jeeten

            Easily scaled up shadouf for raising 40 ton + stones on 120m height?????With what do you build the arm?carbon fibre supplied by aliens?
            DO you even hear yourself?You studied engineering in Calvin and hobbes comics?

            my god…you are humiliating yourslef..i assure you…

          • jhernandez1981

            The most amazing thing about all of this is that you dont know how ignorent you are. People pay you to program software?

            They didn’t need to lift the stones more than a few feet because a) they had ramps and scaffolding to get the stones to the level they needed and b) they were building pyramids, not towers. Those sandstone cubes by the way averaged only about 1.5 meters per side and weighed about 2.5 tons. Only foundation stones reached truly massive sizes and they didn’t need to lift them at all because they were foundation stones and because of the wet sand discovery.

            As for your carbon fiber problem, it really wasnt one. The ancient Egyptians had already developed incredibly strong fibrous composite materials and knew all about wood laminates. Had they needed stronger materials than what was already at hand the tech was there. But considering the weight of what larger shadoofs were known to move its really not hard to envision a system that could easily supend a 3 ton block. Once again – pre-existing technologies that could have easily been adapted and scaled up for the relatively simple job of moving cubes a few feet.

          • KevinLawson

            On balance, you are winning this battle, Jhernandez, but FYI, if you don’t know how to spell “ignorant,” WRITE some software to program a COMPUTER to correct your stoopid mistake.

          • locust

            The stones may have been brought there in much the same way… a small, simple canal. Long forgotten. :)

          • Hosni

            I have no idea if you’re right, but I do know that Egyptians as well as Sumerians (about 500 miles east) were big canal builders. For example, ancient Egyptians dug a canal between the Nile and the Red Sea.

          • KevinLawson

            When you want to be pretentious, say “I want to know with whom I am dealing,” then spit on your hands and rub them together.

          • jeeten

            give the answer about the determinant of a matrix in the context of civil engineering.If you answer that,then i will have some consideration for your answers. Otherwise it measn you did not study any engineering at all.WHich means you could be a 13 yr old kid in the basement trolling around.Or worse,a humanities graduate making alien theories.

          • KevinLawson

            No, you answer the question or the curse of the Pharaoh will cause your engineering diploma to burst into flames.

          • locust

            The pyrarmids each have a hole like a sewer drain way at the bottom in the middle, right? Nobody knows where they go to and they just don’t care. What if they connect to eachother? Perhaps the purpose of the first two was to collect enough water to build the Great Pyramid? They are on a dry plateau next to a massive river. The whole society worked around an annual fpplood season. When the flood season was on, the farmers had no work to do and paid taxes with labor. At this time the river was high. Maybe tunnels to the small one were in place. When the door was opened at the bottom of the bigger pyramid, gravity filled it up… allowing for rafts to float the stones into place like the little pyramid. When the second pyrimid was finished, they had 2 water towers with enough capacity to build the next in the same way. Gravity. Are you all awake yet? ;) , The Locust. :)

            P

          • KevinLawson

            Jeeten, if you don’t even know how to spell what you claim to do, your credibility lacks structural integrity.

          • jeeten

            i asked an engineering question below.Funny you did not reply , but chose grammar as an excuse.Its taught in 1st year engineering,first semester.

          • KevinLawson

            Grammar is taught in first year engineering? I guess you missed that class, eh?

        • Dinesh Ram

          another counterweight.

      • Leonard Llona Lotino

        then how they cut the stones inside the pyramids perfectly sharp and in 90 degrees angle?

        • jhernandez1981

          they had framing squares and copper so they probably used copper saws. That’s how everyone else cut sandstone before the wet saw.

    • Leo

      on wet air !

      • Suman Banerjee

        :P

    • Perquisite

      No lifting was necessary. They used ramps, most likely a spiral square going around the pyramid as it went up. They dragged the stones into place. Then they faced the pyramid in smooth marble and took down the ramp as they finished it on the way back down. Easy peasy. Unless you’re doing the staging…

      • jeeten

        the ramps actually have been discovered in the pyramid structure.

    • Rodrigo Garrido

      Likewise all the temples. Buries everything, then remove the sand :-)

    • BrokenEye

      There’s this wonderful invention called “ramps”. You may have seen them before.

  • Paw Possum

    I personally think this is a crock. The easiest way to move a stone of great weight is to use 4 wooden filler pieces to make it barrel shaped and then roll it. It’s a very simple matter that non-mechanically-inclined people try to make much harder.

    • http://www.roulettestrategytowin.com/ WhatMightBe

      Wood was VERY scarce at the location and no tracks/ruts survive of moving 2,500,000 blocks of stone that each weighed as much as a car…..times 3 pyramids………

      then of course the wheel had not been invented back then…

      • Paw Possum

        Yet we were told wooden rollers were used. Haha, nice try. Blocks like I said could also be reused because little wear would occur. You need to go back to school.

  • MontyBurnz

    Seems reasonable. The water could have come from the ocean since it wasn’t for drinking so the supply of water was abundant. To lift the stones they used a pulley system and to drag them they wet the sand in front.

    • Vladislaw

      The nile river is fresh water

  • http://www.roulettestrategytowin.com/ WhatMightBe

    I found an interesting website on pyramid construction:

    howtheybuiltthepyramids dot com

    In a crazy way string-theory built it………….

  • SaryBasha

    Very interesting theory.. but does not make sense.. if the sand was wet how would you be able to get a grip on the ground to push or pull anything… UPHILL…!! the truth is that “Aad nation” built the pyramids, they were created as giant humans for that purpose.. look it up..

  • Geoff Mather

    Cleopatra lived nearer to us in time than she did to the pyramid-builders.

  • Jose De Jesus Almanza

    The granite stone on the inner parts of the pyramid were imported and all outer layer of stone was made at the site with a simple mold technique of sand and limestone concrete from there quarrys. Its not hard to make something like the pyramids, it just take a shitload of time and thousands of dehydrated ethiopians .

  • disqus_atlq8Zmtsd

    Having read some of Herodotus’ work, I always scoff a little bit at treating him as anything more than anecdotal evidence.

  • Naeem

    How they lifted up the 4500kg blocks??????? With inclined plane??????? Haha its so enormous that wouldn’t be a solution

  • Yassine

    This is not the secret of building pyramids but the secret of transporting blocks only. Be accurate in your titles you’re a scientific not people magazine.

    • Reynardine

      You can also use the sand to make ramps up which the sledges can be pulled with the aid of a block and tackle. That’s how you add the higher courses.

  • Leonard Llona Lotino

    This article still insisting that the pyramids were built primitively. Then how they make the sharp cuttings and accurately 90 degrees angle of the stones inside the pyramid? on what purpose why the pyramids were built? do you really think it is for burial purposes?

    • http://blogs.discovermagazine.com Longmire

      The pyramids were built to guide the souls of the pharaohs to distance stars(the shafts point to specific stars), sounds ridiculous to use but guarantee it’s the case.

    • http://blogs.discovermagazine.com Longmire

      I was aware that the pyramids conduct electricity (as do other large building supposedly) but what was the electricity used for if not for my theory.

  • Reynardine

    Ojel, any Floridian could have told them that.

  • CJ

    Any idea about the quantity of water required to complete the job that too in the desert ?

  • RICHARD MABASA

    maybe it was not the slaves but some goddamn aliens

  • yadu nath

    the main theme is how did they structure so precisely? as there was no any modern technologies

  • jeeten

    meh.

  • roel tipay

    can we do it today?

  • BrokenEye

    You know where else they’ve got water and sand? Mars!

    Coincidence? Yeah, probably

  • http://blogs.discovermagazine.com Harold Ziel

    It’s nice to see some inteligent debating. Other sites quickly turn to politics,
    racecism and vulgarity. I actualy learned things from the commenters. There are many ways the work could have been done. How about this one; Lay down the foundation stones, burry them to the top in sand, lay
    down the next course, bury it to the top in sand, and keep going to the top.
    only the cap-stone would be showing, then remove the sand and dump that into the Nile. The mound builders in Illinois along the Mississippi river
    built their mounds with baskets full of earth…took years, but the mounds
    are still there. This consruction was for religeous purposes, no need for slaves. Never mind my spelling, a spell checker should be provided as
    on other sites.

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