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Pyramid Stones Were Poured, Not Quarried 445

brian0918 writes "Times Online is reporting that French and American researchers have discovered that the stones on the higher levels of the great pyramids of Egypt were built with concrete. From the article: 'Until recently it was hard for geologists to distinguish between natural limestone and the kind that would have been made by reconstituting liquefied lime.' They found 'traces of a rapid chemical reaction which did not allow natural crystallization. The reaction would be inexplicable if the stones were quarried, but perfectly comprehensible if one accepts that they were cast like concrete.'"
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Pyramid Stones Were Poured, Not Quarried

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  • Erich von Daeniken (Score:1, Interesting)

    by Anonymous Coward on Friday December 01, 2006 @03:07PM (#17070054)
    Incidently, von Daeniken claimed exactly that some thirty years ago (?) in his book 'Erinnerungen an die Zukunft' (Memories of the Future), and claimed further that LoneStar were using the pyramid recipe. I didn't expect it would ever come to that, but now I have to say: Daeniken was right in this case (and was proven a rotten liar in dozens of other cases, like that of the 6000 year old battery).
  • by mmell ( 832646 ) <> on Friday December 01, 2006 @03:07PM (#17070064)
    Question 1: Is the activity of casting liquified lime depicted on any pictographs/heiroglyphics in Egypt? The ancient Egyptians had a marvellous habit of recording a great many things on very durable media - including how their own technology worked. I would expect to find depictions somewhere of Egyptians or their slaves engaged in the tasks of manufacturing and pouring concrete.

    Question 2: Is there evidence that the Egyptians used this technology elsewhere? I find it difficult to believe that they would've evolved this kind of technology (concrete) and used it exclusively for the task of pyramid-building.

  • by jbeaupre ( 752124 ) on Friday December 01, 2006 @03:15PM (#17070224)
    The first time was when a researcher about 10 years ago (give or take 10) claimed they were poured because he found a human hair embedded in one.
  • by Beryllium Sphere(tm) ( 193358 ) on Friday December 01, 2006 @03:17PM (#17070272) Homepage Journal
    There's no mention of aggregate, the sand and gravel that cement glues together to make concrete.
  • by eldavojohn ( 898314 ) * <eldavojohn AT gmail DOT com> on Friday December 01, 2006 @03:18PM (#17070296) Journal
    Or the Romans tried many times before creating Bath's and Aqueducts.
    There's a lot of stuff out there that I can grind up and mold. It will last a day. It will last two days. It will last the week and it might even last the season. But when you come to a place of sand and you see these pyramids that have weathered the elements and retained a decent shape for possibly thousands of years, you might say, "What have you got there?"

    I'm not keen on Roman/Egyptian history but I think that the Egyptian society and race are a bit older than the Romans. Wikipedia tells me that the Egyptian empire ran some 7,000 years while the Roman Empire technically only lasted only from 44 BC to AD 476. Ok so in 500 years, how many experiments with possible mixtures could you test. You can test for hardness & solubility on the fly but not duration. If you mix limestone with gypsum, you come up with something like drywall that won't last long at all in the elements. but might initially have a very hard composure.

    Go look at some of the adobe structures that have lasted for hundreds upon hundreds of years in the Southwest of the United States. They were using the most abundant resource that was known to last the longest. R&D for the Romans was probably pretty high quality but I was just speculating that nothing then could match 7,000 years of research for something that would bring your leader's through the ages.

    It was just speculation on my part but I highly doubt the Romans were the sole originators of the formula for the aqueducts. It really is too bad Alexandria was burned. If I could undo one thing in history, I would be tempted to pick that one.
  • by Scothoser ( 523461 ) on Friday December 01, 2006 @03:21PM (#17070360) Homepage

    Good question. The answer to that would be the lack of reinforced concrete. Concrete is a very durable material, but designed to only withstand compression. Because of it's makeup, it's not as durable as stone unless it's been reinforced by something that can handle the tension required to keep it together (like steel rods).

    Think of bricks. Yes, you can build a brick out of mud or clay, and it will work find on it's own. But in order to use it to build structures that were strong, they needed to include a material that can handle tension. Hence the ancient world would use straw. The plant fibers would provide enough strength in tension to build brick buildings.

    But what of other concrete structures you may ask? True, the Romans did build a number of concrete structures that were quite large (note the Pantheon), but they used varying types of concrete with different density levels. This allowed for better construction. But even then, the foundation needed to be stone.

  • by vtcodger ( 957785 ) on Friday December 01, 2006 @03:23PM (#17070392)
    If the Egyptians knew how to form and pour concrete, why on Earth would they drag huge blocks of limestone and granite around to build the rest of the structure? (Maybe Union rules negotiated by the Lower Nile chapter of the Amalgamated Pyramid Craftsmen?) Why not make the whole structure out of concrete? And where are the form marks -- the marks from the boards or whatever that were used to make the form for each block? Granted they'd probably be weathered off from the exposed surfaces, but they should still be there on protected surfaces.
  • Not the first time (Score:4, Interesting)

    by edwardpickman ( 965122 ) on Friday December 01, 2006 @03:23PM (#17070410)
    I've heard this theory before but from what I know the mix they are talking about it isn't nearly as strong as regular limestone. The slower crytalization pattern of natural limestone gives it the strength. I question that artifical limestone would be strong enough for even the top layers of a structure that big. Pure limestone isn't concrete. They aren't talking about concrete, that would be obvious if used, they are talking about reclaimed limestone. There are a lot of problems with that theory. Not the least of which is how would the eygptians make that much lime for the stone? You have to heat the lime dust to a very high temperature to break the chemical bonds. It wouldn't be a small undertaking on it's own and would take huge amounts of energy, charcoal essentially. Wood was scarce. There is no other evidence that they made lime concrete so I have serious doubts.
  • Mortar (Score:5, Interesting)

    by kaoshin ( 110328 ) on Friday December 01, 2006 @03:32PM (#17070576)
    I always thought that the mortar used was more amazing than the blocks themselves. I had this book named the great pyramid decoded which explained that there were blocks held together with sheets of mortar that were in some places as thin as a sheet of aluminum foil. I have read elsewhere on the web that the chemical composition of the mortar is known but that it can't be reproduced today. I may be easily fascinated by this stuff, and there may be an better mortar now, but I just think that is really cool.
  • by Bob Cat - NYMPHS ( 313647 ) on Friday December 01, 2006 @03:45PM (#17070834) Homepage
    is building his own Stonehege - BY HAND, ALONE. []
  • by Anonymous Coward on Friday December 01, 2006 @03:54PM (#17071050)
    In regards to question 1: They often had pictographs of the Egyptians carrying vases up to the pyramids, these could easily hold ash and water and any of the other mixing materials needed. Not that I'm an expert on any of this stuff though.

  • by jafac ( 1449 ) on Friday December 01, 2006 @04:11PM (#17071366) Homepage
    Interesting line of thought -

    One of the main binding factors of ancient Egyptian civilization was the common religion. And an interesting point about the religion, is that they (the priesthood) exercised very strict controls on everything related to the religion, including artistic style (and techniques), monumental architecture, funerary rituals and rites, language, etc. It was this cultural inertia that bound the Egyptian civilization together across thousands of years, dozens of dynasties, even through foreign invasions and occupations.

    The very fabric of the civilization was guided by the notion that CHANGE IS BAD. Pharoh is God. As long as we follow our religion and keep God happy, and make sure God's remains are preserved FOREVER, then Egypt will continue forever.

    By that notion alone, it seems unlikely that there was a vibrant experimentation going on.

    From the art historian perspective, you can compare the stylistic qualities of sculpture over thousands of years, and the features remain virtually unchanged (except for the Armana period, which really only lasted a couple of decades). During Akhenaten's reign, this changed, because he ousted the priesthood, and introduced his own religion - and during this brief period, the art style changed dramatically. Then the priesthood regained control, and used his son, Tutenkamen, as a puppet, to restore the previous order, and the old art style returned, though it was never again as static - and began taking influence from other medeterranean cultures with which the Egyptians traded (ie. Greek, Persian, etc.)

    I'm not saying that they did not discover the perfect concrete formula through experimentation (and it's pretty clear that there WAS a process of improvement in their embalming process over the centuries)- but what I'm saying is that taking 500 years of Roman history, and mapping that over to 7000 years of Egyptian history is like comparing apples to oranges. Egyptian progress most likely moved VERY slowly, in comparison. But they did have a lot of time to work at it.
  • by LurkerXXX ( 667952 ) on Friday December 01, 2006 @04:18PM (#17071494)
    Ding, Ding, Ding. Give that man a cigar.

    You can't just pour something the size of the pyramids and expect to have it set in any reasonable time frame.

    Ever see movies of the building of the Hoover dam? It was done in a lot of small blocks, and for a very good reason:

    "The Bureau of Reclamation engineers calculated that if the dam were built in a single continuous pour, the concrete would have gotten so hot that it would have taken 125 years for the concrete to cool to ambient temperatures. The resulting stresses would have caused the dam to crack and crumble" []
  • Re:It has to be said (Score:5, Interesting)

    by sofar ( 317980 ) on Friday December 01, 2006 @05:10PM (#17072450) Homepage
    "I'd suspect that maybe the stones at the base might have needed to be stronger than the ones near the top."


    The compressional forces that concrete or any mineral type of rock can endure are almost endless. man-made concrete is just as strong as some of the toughest rocks in nature.

    You don't see the grand canyon walls (larger and steeper than any pyramid) collapse? Those are (top 100's of feet) made out of sandstone, which is probably not even as strong as concrete or limestone.

  • by Vreejack ( 68778 ) on Friday December 01, 2006 @05:25PM (#17072722)
    It has been long known that the internal and external blocks of the pyramids were different. It seems that an internal scaffolding of blocks was lain, on which a long pole with a target at the end could be mounted so that the edges could be kept straight and aligned as the external blocks were added. The outer blocks were long thought to be a more attractive grade of limestone, highly polished. They were also highly desirable for building materials and were often stolen by later Egyptians. Since they were more easily stolen from the bottom we have a possible explanation for why the blocks on top seem to be different from the blocks on the bottom, that being that the top blocks are simply exterior blocks which were too difficult to steal.

    The brief article seems to imply that the authors of the study could not be certain of the top/bottom relationship because of their lack of material for study. This is unfortunate as I suspect with more material this hypothesis of their might be completely demolished. I have two major problems with it. First, they are materials scientists, not geologists, so they have no acknowledged expertise in the art of geology. Second, even if they were geologists, they are still arguing from ignorance, claiming that nature could not be responsible for the form of these limestone blocks. Well, nature is often a mystery to those who have not bothered looking at it, and it is easy to claim that something could not happen in nature if you are unfamiliar with it. Just ask the anti-Darwinists.
  • by arielCo ( 995647 ) on Friday December 01, 2006 @05:33PM (#17072874)
    ...from when it was first presented. The heading in the magazine was far more sensational: "Are the Pyramids made of plastic?" and, besides the usual reasoning on the difficulties of transporting huge blocks of limestone along the Nile, and (IIRC) something about composition of at the quarry, it contained two bits of supporting evidence:
    • A microphotograph of what could only be a human hair (vellus) trapped *inside* the stone
    • An account by Pliny the Elder or some other ancient historian, of a "liquid that became dense (solid) when mixed with earth and heated" (it quoted the original Latin, something like "humoris sub terra [...] caloris densar[i]")

    There's some more info here [], about 15% down the page.

    Davidovits referred to the concrete as "geopolymeric", which is surely what inspired the title to the editor. As far as I remember, his approach was still far from Von-Danikenesque and deserved serious consideration.

  • by amolapacificapaloma ( 1000830 ) on Friday December 01, 2006 @06:18PM (#17073668) Homepage
    is building his own Cathedral - with RECYCLED materials and tools, ALONE %ADnez [] /Cathedral_of_Justo_Gallego.JPG []
  • Re:It has to be said (Score:3, Interesting)

    by causality ( 777677 ) on Friday December 01, 2006 @08:12PM (#17075552)
    Actually a number of strange artifacts have been found, such as the so-called Baghdad Battery [] or ancient designs [] that bear a strong resemblence to modern aircraft, or giant figures [] that are unrecognizable unless viewed from the air, or ancient computing devices long before Charles Babbage, [] among others. Also fascinating are ideas about what things like the Ark of the Covenant or the Holy Grail actually were.

    If you pay attention, you will notice that the less discoveries like this fit in with our existing ideas of how things were, the less likely anyone is to have heard of them. If we really valued the purpose of science then we would focus the most attention on the oddball discoveries that seem to defy our theories, rather than the current focus which is on research that is the most likely to be commercially useful and thus the most likely to receive funding. It disturbs me that the mainstream knee-jerk response to anomalies is to find a way to dismiss them based on what we think we know. I would much rather see the fascination with the unknown. Scientific skepticism means you do not draw unfounded conclusions or rely on assumptions; it does not mean that you make excuses for not investigating.
  • by Fantastic Lad ( 198284 ) on Friday December 01, 2006 @10:28PM (#17076906)
    A tamper is a device designed to make sand nice and flat for placing those cute interlocking blocks people sometimes use instead of tarmac on their driveways.

    Anyway, the tamper is basically a big heavy object with a flat bottom and a two stroke gasoline engine mounted to it. When sitting dead, the thing weighs enough to make moving it a hefty undertaking. (I used to work in a machine rental shop, so I know this directly.) But when you set it running, the thing vibrates. When it's vibrating, it's suddenly like pushing an air-hockey puck. Not weightless, but the next best thing, since the tamper is essentially air-bourn by millimeters many times per second. You barely have to apply any pressure to make it drift.

    Okay. Next thought. . .

    Sympathetic vibration. Every object in the world has a natural frequency to which it is tuned. The 'C' string on a guitar vibrates at 'C'. Your house and car also have their own native frequencies. This is why your car rattles when you hit a certain speed, but stops when you pass that speed. (Actually, I know a music student who told me that one of the more clever auto-company innovations was to make the patterns in car tires irregularly shaped so that they would create dissonant rhythms and thus avoid the creation of big standing waves as their rubber textures repeated struck the pavement while rolling. This cuts down on the noise cars make as they drive. I don't know if this helps make cars shake less, but it's a neat bit of info, eh?) Anyway, Tesla was excited by the fact that all objects had a specific tuning, and demonstrated that if you put energy into an object at its natural frequency, it would start to vibrate, and if you put energy in faster than the energy could dissipate, the object would eventually shake itself apart. Oh, that's so cool!

    Now. . , back to Egypt.

    If you were to use the right harmonics to put enough energy into a big block of stone and get it vibrating on its natural frequency, and if you could get it vibrating enough so that it was actually leaving the ground in microscopic amounts as it shook, then you could move it in exactly the same manner you can move a sand tamper. There is evidence that ancient cultures understood these principals, though it is the type of evidence which your run of the mill scientist would probably risk losing his funding over if s/he was seen paying too much interest in it. It's a funny old world.

    --Interestingly, the same knowledge could also potentially be used to grind blocks to perfect fits with other blocks once they are in place. You just vibrate the stone and move it back and forth upon the stone you've just placed it on top of until the surfaces where the two contact are ground to the kind of perfect fits observed in many monolithic structures, where you cannot even push a playing card between the stones. Nobody has really offered a more elegant explanation, but again, there's that loss of funding issue. So it's chisels, throat-clearing and the-other-way-looking among the orthodox thinkers of our day.

    Though, I suppose when you're done you can pour some concrete over the structure and smooth that out so you get a nice triangle-y finish.

    Okay. Warning: Tin-Foil Hat stuff coming up. Forbidden thinking generally leads in that direction for a reason, and you may begin to see why. . .

    The problem with discussing this stuff openly, and the reason it is not, is that the technology of harmonic resonance is a very powerful concept which leads to all manner of different kinds of thinking. When absolutely everything has a wavelength, you can start to come up with some very powerful technologies and ask some interesting questions. Like, what happens when you find the vibrational wavelength of a given brain wave pattern and broadcast that? Can you inflict emotions or other nervous functions? Well, yes, actually, you can.

    Here's a neat little article which mentions casually, (and rather beside the point), that they were using an
  • by Anonymous Coward on Friday December 01, 2006 @11:17PM (#17077226)
    Materials Science and Geology have a long history of shared research. In the Materials Science department in which I am a student, there is a large workgroup of geological engineers within the department. For a ceramicist, it would be relatively easy to differentiate between a structure found in nature and one which was manufactured/

    Fortunately, they actually have evidence to support their claims. You, on the other hand, are the one who is truly arguing out of ignorance. The whole of your argument is that nature is mysterious and that materials scientists are idiots. If you feel that the reaction described is one which is found in nature, then present evidence. Evidence is the light by which we cast away the shadow of ignorance, after all.

I have a theory that it's impossible to prove anything, but I can't prove it.