• Tar_Alcaran@sh.itjust.works
    link
    fedilink
    arrow-up
    26
    ·
    edit-2
    1 month ago

    Ooooh, i love this idiot! It overlaps my historical leather working hobby with my hatred of pseudohistorical bullshit.

    So, a 30m diameter sphere contains 14.000m3 of gas. Every liter of hydrogen lifts 1.14 grams, and for helium it’s 1.05 grams. So 14.000m3 = 14 million liters, or about 14 million grams, which is 14 tons. Sounds pretty decent until you realize that animal hide isn’t exactly weightless.

    A tanned cowhide, before it’s split, is over 4cm thick. Vegetable tanned cattlehide weighs something like 40 kg for a 5m2. But lets see how thick out balloon is. If it can lift 6 tons, it can only weigh some 8000kg itself. Our 30m sphere has a surface area of some 2800m2, so that means our animal hides can weigh, at most, 8000/2800=2.8kg per square meter. Those at home have probably noticed that 2.8 is a bit less than the 8kg you need to use cowhide.

    So, what kind of leather or hide were those balloons then? Well leather is usually sold in “ounces per square foot” (even in Europe), so we can just look it up. 2.8kg per square meter is about 9.2 ounce per square foot (says wolfram alpha), and a handy table I have printed says that’s around 3.6mm thick.

    So, we are too believe that the Egyptians made a 30m balloon, out of what is basically cheap-belt and saddlebag leather, somehow got that not just air-tight, while being ridiculously thin, and then used it to build massive structures.

    • Tyfud@lemmy.world
      link
      fedilink
      arrow-up
      5
      ·
      edit-2
      1 month ago

      Do they need to do that before, or after they learn how to harness a tremendous amount of hydrogen? Which they conveniently forgot to mention anywhere.

      You also think that they would have made a few pictures of that happening, instead of the pictures they did make, which clearly show manual slave labor building the pyramids.

    • ThisIsNotHim@sopuli.xyz
      link
      fedilink
      English
      arrow-up
      3
      ·
      1 month ago

      Not just air-tight, lighter-than-air-tight. I’m not sure if it’s true for the whole set of lighter-than-air gasses, but helium is infamously difficult to keep from leaking, even with modern technology.

      Good at making gasses behave is a weird choice for ancient technologies we lost.

    • KillingTimeItself@lemmy.dbzer0.com
      link
      fedilink
      English
      arrow-up
      1
      ·
      1 month ago

      i think they would likely be using intestines or cow stomachs as did the rigid airships of the time, as it was the only material that could hold back hydrogen, so that would’ve been an option. Especially with leather production, though someone would have to have thought about it first.

      I’m not sure either hydrogegn OR helium would’ve been accessible at the time, though if we’re tying to logically analyze this, its probably worth considering they would’ve alleviated like 80% the mass of the stone, and not all of it, as it’s a little redundant to make the thing float.

    • Valmond@lemmy.world
      link
      fedilink
      arrow-up
      1
      ·
      1 month ago

      Hah gain even more lifting power and also sidestep the whole need of creating helium by filling it with vacuum!

      \s if needed 🤷🏻‍♀️

  • wizardbeard@lemmy.dbzer0.com
    link
    fedilink
    English
    arrow-up
    14
    ·
    edit-2
    1 month ago

    Nope, found my line. This is too absurd and well typed for me to believe this one isn’t just taking the piss.

    • Flying Squid@lemmy.worldOP
      link
      fedilink
      arrow-up
      8
      ·
      1 month ago

      You must not be familiar with Graham Hancock. That’s kind of his whole schtick- sounding like he knows what he’s talking about by sounding erudite but talking absolute garbage.

      • Captain Aggravated@sh.itjust.works
        link
        fedilink
        English
        arrow-up
        5
        ·
        1 month ago

        I mean they weren’t on mute.

        Actually that puts a funny idea in my head. Several pyramids away from Giza, the stepped pyramid, the bent pyramid and the ruined pyramid were all built by Sneferu, Khufu’s father, and obviously only one or none of them could have been his tomb. What if he had some weird obsession that they had to be built in utter silence and gave up on one and made them start again if any of the men so much as grunted?

  • Wilzax@lemmy.world
    link
    fedilink
    arrow-up
    12
    ·
    1 month ago

    Because they definitely had a good supply of helium and/or hydrogen laying around to fill these balloons with, when levers and wheels were too advanced.

    Right.

    • IggyTheSmidge@lemmy.blahaj.zone
      link
      fedilink
      English
      arrow-up
      10
      ·
      1 month ago

      Clearly they used methane.

      Crowds of farm labourers during flood season, all lined up just waiting for their turn to fart into the balloon.

      • HonkyTonkWoman@lemm.ee
        link
        fedilink
        arrow-up
        5
        ·
        1 month ago

        It would be another age before they realized they could fill the balloons twice as fast using camel farts.

    • gmtom@lemmy.world
      link
      fedilink
      arrow-up
      3
      ·
      1 month ago

      You know you can make hydrogen out of water right? You just need high voltage electricity.

      • ivanafterall@lemmy.world
        link
        fedilink
        English
        arrow-up
        3
        ·
        1 month ago

        Likewise, why would they bother with balloons, at all? We know they were highly advanced, it seems more likely they’d just skip to planes?

      • Cethin@lemmy.zip
        link
        fedilink
        English
        arrow-up
        1
        ·
        1 month ago

        I’m assuming you subscribe to the Baghdad battery idea? Even that would produce only a tiny amount of electricity if it did at all. It definitely couldn’t be used for this or even the lighting idea some crazy people support. It may have produced a tiny jolt and have been used for religious purposes as they couldn’t explain the small shock.

  • Vivendi@lemmy.zip
    link
    fedilink
    arrow-up
    2
    ·
    1 month ago

    This is why you need to completely cut off your internet before you take a hit of that good shit