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Engineer: Egyptians built pyramids by piling rubble and attaching bricks later

mirror.co.uk

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Re: Engineer: Egyptians built pyramids by piling rubble and attaching bricks later

#31

Post by schiffern »

FrankenPC wrote: post #21
MarcusBrutus wrote: post #16

I am not convinced that the Egyptians could build watertight channels at this scale, especially those shown climbing up the slope of the pyramid which would have to be watertight at the top too, and under great pressure. Also one or two packages could easily get stuck in the "pipe" jamming the whole thing. Finally, the video likely downplays the number of floaters necessary to lift a block of stone.

Yes. I thought the same exact thing. Also, I was wondering exactly how the water was magically moved around a the top of the pyramid? I can see evacuating sections, but then you would have to wait for the next rains to refill them. That would take an incredibly long time. Imagine how much work would be required to bring more water to the top of that pyramid to refill the sections AND the leaking flotation columns. He…

>That would take an incredibly long time.

Note that Egypt was a lot wetter when the pyramids were built (circa 2500 BCE). http://www.pbs.org/wgbh/nova/next/ancient/climate-change-may...

>Heck, imagine the PSI of water at the bottom of the pyramid columns when they were reaching a hundred feet high?

A column of water 100 feet high exerts 43 psi at its base.

Re: Engineer: Egyptians built pyramids by piling rubble and attaching bricks later

#32

Post by FrankenPC »

schiffern wrote: post #31
FrankenPC wrote: post #21

Earlier quoted context omitted.

Yes. I thought the same exact thing. Also, I was wondering exactly how the water was magically moved around a the top of the pyramid? I can see evacuating sections, but then you would have to wait for the next rains to refill them. That would take an incredibly long time. Imagine how much work would be required to bring more water to the top of that pyramid to refill the sections AND the leaking flotation columns. He…

>That would take an incredibly long time. Note that Egypt was a lot wetter when the pyramids were built (circa 2500 BCE). http://www.pbs.org/wgbh/nova/next/ancient/climate-change-may... >Heck, imagine the PSI of water at the bottom of the pyramid columns when they were reaching a hundred feet high? A column of water 100 feet high exerts 43 psi at its base.

OK. So, the great pyramids were nearly 500ft tall. At the top, the pressure below would have been around 200psi. Even the most stalwart modern plumbing fixtures have trouble past 72psi. 100psi is the upper limit before things start to fail. I don't think that there would be a mechanical problem with stone holding back that pressure, it's the leakage that would be the killer.

Re: Engineer: Egyptians built pyramids by piling rubble and attaching bricks later

#33

Post by mekoka »

MarcusBrutus wrote: post #16

I am not convinced that the Egyptians could build watertight channels at this scale, especially those shown climbing up the slope of the pyramid which would have to be watertight at the top too, and under great pressure. Also one or two packages could easily get stuck in the "pipe" jamming the whole thing. Finally, the video likely downplays the number of floaters necessary to lift a block of stone.

As it certainly doesn't need to be proven further, Egyptians were quite an ingenious people. All of the things you're suggesting as obstacles would probably be trivial to deal with for them at their advancement level. A commenter (seferphier) posted this link that may provide a glimpse into additional possible cues, I suggest to have a look http://www.youtube.com/watch?v=C1y8N0ePuF8&feature=youtu.be&.... I particularly liked the part where it is suggested that it would be relatively easy for them to move 600 litres of water in a single minute. With virtually unlimited water and such a capacity to move it, I think the theory might be plausible and merits further investigation.

Re: Engineer: Egyptians built pyramids by piling rubble and attaching bricks later

#35

Post by jws »

Not passing the sniff test for me. Three flaws at first glance…

At the end he describes lowering blocks into place by incrementally removing bladders. This does not work. As soon as you are fully submerged and displacing with bladders you are unstable. As your depth increases, pressure increases, and your displacement goes down making you sink even faster. The good news is if you get neutrally buoyant you could poke the blocks down into place and they wouldn't weight much so you could move them around then remove the bladders.

Also not covered was how the water gets to the top. Each lock load of blocks and bladders requires at minimum the same mass of water to be lowered (to fill the lower lock chamber). In practice it will be at least several times this in order to keep the blocks from jamming in the chamber. So each ton of block effortlessly floated to the top will take several to many tons of water laboriously hauled to the top. Hauling water is probably lower friction than stone, compared to the volume multiplier, I can't say who wins.

The inner lower lock door is also a problem. It has to contain water at something like 10 atmospheres and be loose enough to move. Plus, if shaped like the video, it needs to weigh 150lbs/in^2 to keep from being blown out when raised. That makes it about 120 feet tall if made from limestone.

Re: Engineer: Egyptians built pyramids by piling rubble and attaching bricks later

#37

Post by fblp »

seferphier wrote: post #3
Freestyler_3 wrote: post #2

Good theorie, but now i wonder how they got the water up. There must be evidence of pump or large amounts of buckets :D

I was wondering too. This video explains in more detail how they used pressure to move the water up http://youtu.be/C1y8N0ePuF8?t=15m20s

Archeologists would be able to find evidence of these water piping from springs underneath the pyramid.

Re: Engineer: Egyptians built pyramids by piling rubble and attaching bricks later

#38

Post by mekoka »

FrankenPC wrote: post #32
schiffern wrote: post #31

Earlier quoted context omitted.

>That would take an incredibly long time. Note that Egypt was a lot wetter when the pyramids were built (circa 2500 BCE). http://www.pbs.org/wgbh/nova/next/ancient/climate-change-may... >Heck, imagine the PSI of water at the bottom of the pyramid columns when they were reaching a hundred feet high? A column of water 100 feet high exerts 43 psi at its base.

OK. So, the great pyramids were nearly 500ft tall. At the top, the pressure below would have been around 200psi. Even the most stalwart modern plumbing fixtures have trouble past 72psi. 100psi is the upper limit before things start to fail. I don't think that there would be a mechanical problem with stone holding back that pressure, it's the leakage that would be the killer.

The theory mentions multiple shafts, not a single contiguous one.

Re: Engineer: Egyptians built pyramids by piling rubble and attaching bricks later

#39

Post by DanBC »

ilaksh wrote: post #17
kylelibra wrote: post #4

Questionable source imo.

Why would an archaeologist be more qualified to guess how they built the pyramids than an engineer who studied the pyramids for years? Or are you saying we should just dismiss all of the content because you don't like the organization that published it? I question your belief that you can evaluate information based on the organization that provides it. Or at least that some popular or well-respected organization can…

Do you treat all P=NP proofs as of equal worth and spend time carefully checking them to see if they might be accurate? Or do you apply some filtering first - reputable journal etc?

Discounting stories in the Mirror and Mail is a totally reasonable tactic.

UK papers do not have fact checkers like US publications. UK papers very carefully report what someone says, even if most people agree that person is a wingnut and talking nonsense.

Looking at the UK tabloid newspapers we see some deeply nasty methods where blatant lies are told and nonsense peddled.

If the Daily Mail told me that grass is green I'd have to go out and check.

Re: Engineer: Egyptians built pyramids by piling rubble and attaching bricks later

#40

Post by skylan_q »

thearn4 wrote: post #8

Interesting idea, and maybe one worth investigating further. I've always liked the internal ramp theory: https://www.youtube.com/watch?v=Ws4O5LOCI68 In the end, lets all at least agree that it was human innovation and not alien technology that built the pyramids.

1. People, in general, are smarter than the ancients and civilization has progressed since then.

2. We don't know how they built the pyramids.

Either aliens built the pyramids, or we're dumber than the ancients.

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