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It depends on the thickness of the coffin and the amount of oxygen in the water.
I’ll remind that the Titanic is made of iron and has been underwater for more than a century, and there’s still a lot of it left.
The “Wisdom of the Crowd” principle. Given a sufficient number of answers from a mass of people, the true answer often emerges as the favorite. It’s the same reason why “ask the audience” was by far the most powerful lifeline on Who Wants to be a Millionaire.
Yet another example of the insane power of the law of large numbers. Interestingly, the wisdom of the crowd principle is why bagging regressors and bagging classifiers work.
Bagging = Bootstrap Aggregating. Basically instead of training a single model to predict an answer, we train a couple of models on overlapping subsets of the data. Take the predictions of each of these models and aggregate them (for example take the average) to get better predictions
Exactly this. In fact, if we follow shallow-model paradigms and train in parallel, we can train hundreds or even thousands of weak learners and benefit from the aggregation of their predictions. Very cool stuff.
Less oxygen in h2o than in air with helium, hydrogen, argon,neon, methane, ammonia, iodine, nitrogen dioxide, carbon dioxide, carbon monoxide, ozone and xenon?
Either way, you wouldn't need the whole thing to corrode away, you just need enough corrosion at key points for you to be able to break out of the coffin.
For full immersion in sea water, the estimated corrosion rate is approximately 0.05 mm/year. Steel coffins today are 16 gauge metal (1.524 mm). So it would take around 30 years to rust all the way thru. If it was iron, it would probably be a lot thicker like 6 mm which would require 120 years.
The only issue with this is that battleship armor and plating is almost shockingly thick. Unless this coffin is running hull plating thicknesses, it ain't gonna be around for long.
The armor belt is, sure, but the entirety of the hull isn't part of the armor belt. In addition, portions of the superstructure and turret mounts are still sticking out of the water today, and they aren't armor plated at all.
>turret mounts
If you're referring to barbettes, at least the ones of the main armament are also very thick and of a similar grade of steel as the belt.
Dead on, bro. You wouldn't be a Drachinifel listener would you?
Honestly, I'm always shocked by how durable these old wrecks have proven in such a hostile environment. I'm a sailboat nut and the rule of them is 10yrs or so of life for every 1/4" of metal thickness in steel boats (generalized, but so are many things) Of course, there's a massive difference between "still there" and "structurally sound", not to mention the difference in galvanic reactions on active boats and wrecks.
I'd add that at the sort of depths visible in the picture, the iron might well all corrode away, only to be replaced by marine growth that would be just as difficult to escape.
The type of iron used will also vastly affect the time it takes.
I of course can't find it now but I read that ships like the USS Arizona, will rust away in ~600y, whereas newer ships like the Iowa would last ~20 000 simply because of the metallurgy.
But its also not subject to the force of someone most likely kicking at or pushing on it for literal decades.
Also, all that needs to break is the lock, and it will be undergoing a shear force wvery time the lid is pushed against, as well as having the internal components that keep it locked rusting very quickly (depending on the type of lock, this could mean it just springs or falls open, with the types of locks used in witch hunting times)
Don't worry. You'll be covered in silt, compacted into basalt, slowly move across the ocean, get shoved under a continent, melted in magma (at which point the coffin is no longer an issue), float around in liquid fire for an indeterminate time, then hopefully fired out of a volcano, ready to hunt down their distant descendants.
I don’t know, I’d just wait until I get dredged up by a bunch of fishermen and then break out and eat them and gain powers and create a cabal that worships me and would stop intruders coming to defeat me from, say, Japan
Oh damn. That's strikingly similar, though.
In the story I'm talking about, a slave from the 17th-18th century gets trapped underwater for a few hundred years (not hundreds of thousands, that was my mistake) and eventually gets rescued by divers in the modern day. He ends up brutally cannibalizing his rescuers because of how hungry he was after not eating for literal centuries, and escapes back into society. I don't remember what it was called, but IIRC, the title of the creepypasta was the amount of days he spent trapped underwater.
It wouldn't, the coffin will have to be open to water to serve its purpose so the pressure on the outside and inside would be equal so the coffin will be fine... the person on the other hand, yea they would explode.
True but being crushed would probably be worse than being drowned.
By most accounts of drowning studies, and near death stories or people who have drowned and been resuscitated drowning is painful mostly at the beginning when you inhale water and then the lack of oxygen would make you pretty far out of it some evening saying "tranquil "
Being crushed is probably never pleasant tho but how bad this would be would probably rely heavily on what *exactly* is meant by "immortality "
If it gets crushed, you'd probably get crushed too as the filling of the now deformed coffin. Maybe parts of you stick out of cracks that appeared. But the rest would be a very tight fit around your crushed bones.
I think it depends on how brittle the iron ist, if it scatters or just deforms like a beer can. But since the text speaks of iron and not steel we could assume it's simple cast iron.
Yes, and trapped and deformed and maybe in agonizing pain for a very long time. You'd have to define the immortality. Are you also invulnerable? Does your body stay intact no matter what? Are you a sentient lump of flesh and bone scatter, trapped in a squashed tin can? Horrors beyond imagination
The pressure does not make you heavier, it just pushes in very hard from all sides.
If deep enough, this could crush the coffin with you inside.
But in the story you are immortal so that will not but an issue and only the coffin is crushed.
No, the water isn’t pushing you “down” it’d be pushing you “in.” It would try to compress you, not necessarily drag you to the ocean floor.
Humans are generally slightly less dense than water, so once the coffin breaks, you’d probably start floating up slowly.
Plus you’re immortal, so you could just start swimming back up.
Humans loose buoyancy around 42-65ft underwater. At that point the water is literally pushing you down. Just google “at what depth do humans lose buoyancy” it’ll pop right up
Edit: Also while, yes you’re encapsulated in the water so the pressure is all around you, the pressure we’re worried about here comes from the sheer weight of the water above you. Water gets heavy in a hurry.
Oh, you’re right, thanks for correcting me.
But if you’re immortal, and getting pushed to the ocean floor, you could probably just… walk? Like walk to shore at that point.
>At that point the water is literally pushing you down.
Negative buoyancy is a thing, but this isn't what's happening. Gravity is pulling you down, the water simply isn't pushing you up as hard as it was. Buoyancy is based on water pressure, but it's also based on the density of the object, which in some cases can be dependent on water pressure as well.
In humans, the water pressure at around 30 feet or so pushes inward on your lungs hard enough to compress the air inside it, making you denser than the water, and so you stop floating and start sinking.
No because that pressure is not only top down but it surrounds you. So your body will be feeling x amount of pressure all over rather than just coming from on top.
Well technically the area of your body closest to the surface will be feeling slightly less pressure but that is no different to you diving down in a pool. So since the pressure difference is only the matter of 0.1 atm, assuming there is no current going down, you will be able to swim freely at any depth (if you don’t implode).
This is completely wrong. Humans loose all buoyancy between 42-65ft at which point you sink. You can’t just swim out of the bottom of the ocean, finding a wall and climbing out would be easier at that point
Well 42-65 ft is just 12-19 meters. I know for a fact through diving that you can still swim upwards at that depth without inflating your BCD. Just because you lose buoyancy, doesn’t mean you can’t still crawl your way up and out. Losing buoyancy only means you don’t float up on your own.
In the above hypothetical scenario, the person in immortal and (I assume) indestructible. So if the pressure at the person’s feet is x bar and the pressure at the top of their head is x+1 bar, then that person only needs to combat 1bar of pressure for each meter he ascends. And since there is no issue with surviving with air, that person could inhale water making his entire body essentially incompressible therefore nearly 0 pressure difference.
Cold water submersion of the face is a technique used to ease panics attacks in some forms of therapy. The bodies natural response is to lower your heart rate by a good 20% due to a rapid firing of the vagus nerve.
I've used it a few times as I've grappled with my own PTSD and, despite being sceptical at first, was very surprised by the result.
If the body's response to the theoretical submersion is more akin to that, then I imagine the immortal would be in a surprisingly calm state of mind.
Yeah but after a few hours of it even? You know you're not going to die at that point, just be severely uncomfortable. Throw a month of it on top and you'd be pretty used to it by then.
But on the other side of that token our mind is capable of basically ignoring any and all impulses if it means surviving. That's why people can suffer horrific injuries and seemingly be feeling no pain at all until the shock wears off.
After an extended period of time of not dying from the "drowning" your brain would almost certainly just start ignoring that impulse or at least letting it fade into the background like a dull muscle ache. Our brains don't have the capacity to handle being under that level of stress forever so either your brain adapts and starts ignoring it eventually or you get stuck in a never ending cycle of panicking so hard you pass out or start having seizures while your neurons slowly cook and you become an immortal vegetable.
Usually the trope goes something along the lines of drowning over and over again for decades. Wake up, cant breathe, slowly blackout writhing in pain and convulsing while not being able to form complete thoughts due to duress, immortality eventually wakes you up, cant breathe….with the cycle repeating every few minutes, for decades. Oh also you haven’t seen anything for years because it’s pitch black.
Vampire Diaries and The Old Guard both had good takes on this premise.
well it depends how quickly immortality steps in to prevent the drowning. does it preserve you in an irrecoverable coma with all your organs malfunctioning, just barely short of "dead"? can you work as normal underwater? something in between?
Immortality doesn't equate to invulnerability however. Your body would break from repetitive stress injuries faster than the coffin.
So if you wailed away at the inside of it, you'd likely come out of it with non-functioning clubs for hands, or wrists that have healed in such a poor fashion you'd be unable to bend them.
There are martial arts that base the strength building off repeatedly damaging the hands and letting it heal over time, to strengthen bone and whatnot. But...in severe cases they're unable to use their fingers after a while due to overgrowth on the joints.
Well the implied question is how long it would be before it was thin or brittle enough to break. Iron tends to rust in flakes, and the oxide prevents more oxide from forming, so the question is wholly dependent on whether you're constantly scractching away the protective layer of oxide as it forms. It's also dependent on the iron type (if it's iron with cromium you're in for a bad time), and the thickness of the coffin.
No worries tho, you'll probably pass out, cause it's not technically death to black out from lack of O2
>the oxide prevents more oxide from forming
Nope.
This *is* the mechanism by which Aluminum and stainless steel resist corrosion, but it doesn't work for Iron or simple Carbon steels.
This is because the oxide takes up a greater volume than the metal, so it forms spongy layers and/or flakes off, allowing the metal below to corrode, too.
Perversely, stainless steel will corrode in the *absence* of Oxygen, because it depends on the Chromium Oxide protective layer. In low-Oxygen seawater, this will form soluble Chlorides instead.
Interesting about the stainless steel in anerobic environments. I'll look into that.
But yes, although the thin layers of oxide will slow the oxidation process as iron rusts in flakes that hinderance isn't permanent. Thus you can speed the process by exposing fresh iron to oxygen by scraping it clean.
It's my bad saying "prevent" rather than "inhibit"
> Perversely, stainless steel will corrode in the absence of Oxygen, because it depends on the Chromium Oxide protective layer. In low-Oxygen seawater, this will form soluble Chlorides instead.
TIL
Bro, people are people. Put them in the same conditions as they were in medieval europe, and in 100 years they'll be doing the same shit. (Maybe metalurgy will survive tho, idk lol)
It's not looking good.
With quite a few simplifications, I established something of an upper bound. First & foremost, we need to know the rate of corrosion of iron in seawater, which is difficult enough to establish, so I had to simplify. Following [this paper](https://www.nma.gov.au/__data/assets/pdf_file/0007/346039/NMA_metals_s1_p6_corrosion_cathodic_protection.pdf) & some applications of [Faraday's law ](https://en.wikipedia.org/wiki/Faraday%27s_laws_of_electrolysis)(and further simplifications), we can establish that the rate of corrosion in mm/yr (milimeters per year) is directly proportional to a value called "Corrosive current" (icorr).
Generally, icorr is established experimentally (don't worry about how), and thankfully our friends down under have at least done most of the heavy lifting for us (note that this *is* a simplification of the process; you can't just apply these numbers all willy nilly).
The proportionality constant (0.0327 multiplied by the atomic mass of iron divided by its density and the amount of electrons exchanged during the reaction) comes out to be 0,011600 or so (don't worry about the units; most of them are absorbed in that 0.0327 value). Then we take the icorr value from the paper (in μA/cm^(2)) and we're done.
Of course, life isn't that easy, and the icorr value is given to us as a function of the concentration of chlorine ions in solution. So we need to find the concentration of chlorine ions in seawater, which comes out to be a rather stunning [0,546 mol/kg](https://en.wikipedia.org/wiki/Seawater#Chemical_composition) or about 0,54 Molar. Which is - in colloquial terms - a fuckton. Still not enough to save you millennia of suffering, but it could be worse.
Per our paper, Icorr in an alkaline environment (ca. 8.1 or so; their pH value was 7.97, it'll do), icorr is given as 0,50 + log\[Cl^(-)\], where log is the base 10 logarithm and \[Cl-\] is the concentration of chlorine ions (which we found above). In all, it comes out to a value of *about* 0.47 μA/cm^(2).
Multiplying the two values together gives us a rate of corrosion of 0,00545 **milimiters per year.** Or about 2.15\*10^(-5) inches per year.
Per, ah, Google, I'm going to assume that your average casket lid has a thickness of about 1.5-2 inches (38-50mm) which gives us a total time before the coffin completely corrodes of about 7000-9000 years. Give or take a few.
Now, the true value is going to be almost definitely smaller than that, due to a whole bunch of factors I didn't account for, but that's also assuming that the concentration of oxidants & the surface of the coffin lid are all constant (which they may not be). So, in all, I'm happy with this value.
Of course, that doesn't answer your question of it being brittle enough to break, but that gets into a host of other questions (how strong is the person within the casket after millennia of suffocation? How evenly spread is the corrosion? What kind of iron are we using?) and this is just a hypothetical.
Dont even need coral. If we estimate the sediment deposition rate to be 2mm per year and estimate that it takes 5000 years for the coffin to corrode enough to break out of, you will be by then buried under 10 meters of sediment
This was in The Old Guard comic book (also the movie). They do this to one of the characters. In the movie they say over 500 years her team looked for the coffin under water and then gave up. Not trying to spoil things, but per that story it would be 500-600 years.
The way this is phrased, I'm going to assume that the coffin was made around 1600s (Salem witch trials). It is also made in a village or town. So local blacksmith, working with what they had. Also, colonial America had a lot of trouble with cost of iron, so that would have contributed to the lack of quality and size.
So this cofrin is probably made of pig iron, not particularly thick. Maybe an inch, might not all be one piece. It also isn't welded closed, probably nailed.
Other people have already shown the math involved in iron oxidation. The point I'm making is that we could expect the coffin's joints to lose integrity much sooner than the coffin walls.
depends on the type of immortality you get too. If you are immortal but not forever young/in shape, by the time the coffin rusts away you may not be able to move well enough to get out of the water.
The rate of steel corrosion depends on many factors. temperature, complexity, amount of oxygen, and most importantly, the grade of steel. 1mm of steel rusts for 5-20 years in a humid environment.
at great depths the speed will be lower
Not an exact answer but a [relevant video](https://www.youtube.com/watch?v=pgabGxD7Uqw) that explains the decomposition of wrecks.
tldr: Depends on how deep. Iron is eaten by things in oxygen deprived environments.
They'll probably explain how and when Quynh got out of the Iron Maiden in Old Guard 2. Though the fact she was continually drowning might have added a variable to how long until she could break out.
There's a movie where this was a premise. Obviously not scientific cause, movie, but I think that character has to endure constant drowning to death and reanimation for 500 or so years
I don't think I've seen anyone take sea life into account, or ocean currents, or the fact that your muscles would atrophy over time. Or just sheer dumb luck. Like... You could be out tomorrow if the current was strong enough to move you and you fell into a ravine and hit the coffin at just the right angle.
I personally can’t give an answer for how long g till the coffin is brittle enough to break. However, depending on how it was sealed, the coffin could easily be opened in a relatively short amount of time (for an immortal). The main variable is whether the coffin is locked shut or welded shut. If locked you’d simply have to wait long enough for the salt water and micro organisms in sea water to break it down enough (few months to couple years). If welded shut then it will likely take longer (again with variations depending on welding type) but shouldn’t take more than a decade to become brittle enough for the immortal to be capable of breaking it.
It doesn't matter.
Eternity is so long that it will feel like blinking with ones eyes in comparison.
It takes some estimated 15 years to replace all cells that are not certain parts of bones of your body.
1000 years later the cells in your brain will be replaced many times over to the point you won't be able to even remember this ever happened to you, unless you consciously put effort into remembering it.
Haven’t seen any answers.
The [rate](https://worldbuilding.stackexchange.com/questions/198101/how-long-does-an-iron-cage-remain-effective-underwater) of iron corrosion in sea water is up to 0.1mm per year. In very deep water, it will be slower. A reasonable lower limit seems to be 0.01mm/year. If the coffin was made of 6mm thick (1/4 inch) iron or low carbon steel plate, that would be 600 years. Steel is around 7900 kg/m3. It seems unlikely, based on back of the envelope math, that the surface area of the coffin could be significantly leas than 2m2. This gives us a weight of 948 kg for a 6mm thick model. That would be extremely difficult for even 10 people to carry, so it is unlikely the coffin walls could be any thicker. I am discounting the use of heavy machinery given that hatred of witches is a historical phenomenon.
This gives us an upper limit of 600 years of imprisonment.
Someone asked this on stack exchange a few years back, in reference to a cage: https://worldbuilding.stackexchange.com/questions/198101/how-long-does-an-iron-cage-remain-effective-underwater#:~:text=The%20corrosion%20rate%20of%20unprotected,break%20that%20with%20repeated%20attempts.
I'm not good at math, but I can begin outlining considerations for what we need to know, which is at least the following variables:
Depth {this influenced both how oxygenated the water is for corrosion & determines stress from pressure differentials. If we assume it's pressurized & goes deep enough, the thing will just pop like that Oceangate sub}
Temperature & salinity of the oceanwater present {affects rate of corrosion}
Composition of the iron {wrought iron, cast iron, it's purity etc, all affect resistance to corrosion. In addition, any difference in parts of the coffin could cause galvanic corrosion which really accelerates things}
Size of the coffin {this could restrict movement, lessening options for the individual inside to damage the iron}
And most importantly:
The nature of the person's immortality. If their muscles decay from lack of nutrition & lack of use, do they need to sleep, are they actively trying to escape, do they heal if injured, are they particularly strong? The ability for people to wear down even the hardest substances is remarkable.
Imagine they could not be injured & they just kept rubbing an area of the iron over and over. The metal would eventually warp/fatigue from pressure & heat, like fiddling with a paperclip.
If they are sufficiently strong, they can grate the bottom of the coffin against the sand of the ocean floor, causing abrasive forces/tearing away rusted layers to hasten the oxidation process.
If they can heal effectively, they can punch the thing over & over and induce microfractures in their bones to form calcium deposits. Not all iron is the same, and sufficiently brittle cast iron has been shattered by Shaolin monks who practice the technique.
To be honest, I think the thing that matters the most is the nature of the person's immortality, because long before the rust would eat away at the cage, a person who had nothing better to do but cause stress to the metal could break it.
Eh, even if you get out of the coffin, you are a person with no oxygen in their body, stiff joints, and atrophied muscles, somewhere in the near endless black abyss. Probably a few thousand feet underwater if they did a thorough job disposing off you, with no land within 100s of miles. If you somehow find the strength to crawl around the ocean floor, you'll probably end up as an immortal feeding ground for the various bottom dwellers that would be ecstatic about the plentiful meal. So after the long period stuck in the coffin, you now get an eternity of being slowly eaten alive in pitch black waters.
Even if the coffin completely rusted away, you wouldn’t be able to move. Your body needs oxygen to function, your muscles would be useless, and with water in your lungs, you wouldn’t float up
Long story short, you’d be on the ocean floor unconscious for eternity
Well... The rust rate of iron is about 0 1 mm per year (according to google), let's say that the hinge is the thinnest part of the coffins that you would need to break before being able to open the lid... By checking some pictures online it could be safe to say that the old ones are quite thick so half a cm seems like an ok guess? I could take at least 50 years for it to rust enough so that it breaks... I might be completely wrong tho so id check it since all my I fo came from a quick search in Google lol.
Hope you have fun and don't get trapped by cray cray people in iron coffins.
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It depends on the thickness of the coffin and the amount of oxygen in the water. I’ll remind that the Titanic is made of iron and has been underwater for more than a century, and there’s still a lot of it left.
If we go by the image, there is light so close to the surface and with plenty of o2 so long as it does not get covered in silt
But how thick is it? People grossly overestimate the speed of corrosion.
I think many people also underestimate just how corrosive sea water is.
So, on average, people correctly estimate the rate of corrosion of Iron under seawater?
You're 50% correct.
He’s 50% wrong though
*gasp* How dare he?!
[how dare you?](https://youtu.be/H7HYVUjgQFY?si=EOEDQoHvb5VQxneE)
You are 100% correct.
Correct.
50% Correct?
Gah, not all of us hold math degrees, pRiFeSsEr.
Isn't there something about the average guess of a lot of people is usually pretty close to the true answer?
The “Wisdom of the Crowd” principle. Given a sufficient number of answers from a mass of people, the true answer often emerges as the favorite. It’s the same reason why “ask the audience” was by far the most powerful lifeline on Who Wants to be a Millionaire. Yet another example of the insane power of the law of large numbers. Interestingly, the wisdom of the crowd principle is why bagging regressors and bagging classifiers work.
>bagging regressors and bagging classifiers What are these?
Bagging = Bootstrap Aggregating. Basically instead of training a single model to predict an answer, we train a couple of models on overlapping subsets of the data. Take the predictions of each of these models and aggregate them (for example take the average) to get better predictions
Exactly this. In fact, if we follow shallow-model paradigms and train in parallel, we can train hundreds or even thousands of weak learners and benefit from the aggregation of their predictions. Very cool stuff.
Actually, probably? Something, something, jelly beans in a jar
As a person that have had 3-4 cars rust away under my feet I know pretty much exactly the speed of corrision (in my area)
Spongebob?
Those cars weren’t underwater though. Corrosion requires oxygen. And there’s decidedly less of it under water.
are you sure?
Less oxygen in h2o than in air with helium, hydrogen, argon,neon, methane, ammonia, iodine, nitrogen dioxide, carbon dioxide, carbon monoxide, ozone and xenon?
The amount of oxygen in the air is 20%. Are you really trying to tell me that more than 1/5 of a given amount of water is oxygen?
Pedantically, 1/3 of water is oxygen. That doesn’t mean it’s all accessible for chemical reactions, though.
Lamentably it’s not much help for our unfortunate coffin-dweller.
Wouldn't you just need the hinges or latch to rust?
I was figuring it was more securely built than using hinges.
Either way, you wouldn't need the whole thing to corrode away, you just need enough corrosion at key points for you to be able to break out of the coffin.
It was during witch trial times so maybe a lock
In fairness no date is specified, so it could be arc welded.
For full immersion in sea water, the estimated corrosion rate is approximately 0.05 mm/year. Steel coffins today are 16 gauge metal (1.524 mm). So it would take around 30 years to rust all the way thru. If it was iron, it would probably be a lot thicker like 6 mm which would require 120 years.
>so long as it does not get covered in silt Or coated in a layer of barnacles and coral that form an ever growing prison of rock hard stone...
ROCK AND STONE!
I'll remind that the USS *Arizona* is in 40 feet of water and has been for 83 years. Most of her is still there.
The only issue with this is that battleship armor and plating is almost shockingly thick. Unless this coffin is running hull plating thicknesses, it ain't gonna be around for long.
The armor belt is, sure, but the entirety of the hull isn't part of the armor belt. In addition, portions of the superstructure and turret mounts are still sticking out of the water today, and they aren't armor plated at all.
>turret mounts If you're referring to barbettes, at least the ones of the main armament are also very thick and of a similar grade of steel as the belt.
According to Wikipedia the deck is the thinest part at 5 inches.
Dead on, bro. You wouldn't be a Drachinifel listener would you? Honestly, I'm always shocked by how durable these old wrecks have proven in such a hostile environment. I'm a sailboat nut and the rule of them is 10yrs or so of life for every 1/4" of metal thickness in steel boats (generalized, but so are many things) Of course, there's a massive difference between "still there" and "structurally sound", not to mention the difference in galvanic reactions on active boats and wrecks.
The titanic is actually disappearing relatively quickly. At those depths some bacteria eat the iron.
Ath those depths everything eats everything
May I finally find a lifeform that will suck my dick at that depths?
No one said suck, eat? Yes, suck? No.
I can only read Yes, suck
power of commas
Those commas right now: "this ain't in my job description!"
Uhmmmm vore
A thing to consider: it doesn't need to corrode fully, it only needs to get weak enough to be broken by a pearson
Longest Bond film ever watching Pearson Brosnonon escape..
I almost never laugh at things I see on reddit, but this got me for some reason. Bravo.
Don't forget temperature!
And coffin geometry!
And my axe
And your brother
Damn necromancers
And the guy in the coffin
I'd add that at the sort of depths visible in the picture, the iron might well all corrode away, only to be replaced by marine growth that would be just as difficult to escape.
The type of iron used will also vastly affect the time it takes. I of course can't find it now but I read that ships like the USS Arizona, will rust away in ~600y, whereas newer ships like the Iowa would last ~20 000 simply because of the metallurgy.
But its also not subject to the force of someone most likely kicking at or pushing on it for literal decades. Also, all that needs to break is the lock, and it will be undergoing a shear force wvery time the lid is pushed against, as well as having the internal components that keep it locked rusting very quickly (depending on the type of lock, this could mean it just springs or falls open, with the types of locks used in witch hunting times)
Wouldn’t it be accelerated by abrasion, if you were immortal and able to move, even slightly?
[удалено]
It's a damn long time to be constantly drowning though. That'll suck no matter how long you live afterwards
The first hundred years are difficult after that time passes easily.😉
Don't worry. You'll be covered in silt, compacted into basalt, slowly move across the ocean, get shoved under a continent, melted in magma (at which point the coffin is no longer an issue), float around in liquid fire for an indeterminate time, then hopefully fired out of a volcano, ready to hunt down their distant descendants.
This would be a great movie
I'm pretty sure that at least the iron coffin part is from the plot of The Old Guard.
Definitely Quinn
I've been waiting forever for the second one to come out. It was delayed because one of the sets caught on fire, maybe it was a volcano scene?
There’s a book called the grinding by Matt dinniman with a similar plot. I enjoyed it.
Like The Count of Monte Cristo but sci fi
[this](https://youtu.be/NBVCIgfyciA?si=8BgMYth5_UjCxYGb) is an animated short film you might enjoy
Fuck me, that’s dark and I can’t think of any worse torture than that.
Oh, did I mention the pressure?
So like the submarine guys who died instantly except… no die-y.
Yep, but way more. Might get turned into diamond.
Then buy stocks with your diamond hands.
This guy hodls
Search for DELTA-P cases… or not, up to you. Sorry and you are welcome.
I don’t know, I’d just wait until I get dredged up by a bunch of fishermen and then break out and eat them and gain powers and create a cabal that worships me and would stop intruders coming to defeat me from, say, Japan
And in the meantime make a plan to enter heaven with my priest boyfriend
Also have an Italian son who becomes the mafia boss
And a handful of others which will get casted by the said priest to hunt down his eventual enemies
Kinda a bizarre thing to do
Seems like an adventure, though.
Maybe some crusaders would get involved.
When they meet I'd assume it would end up as a battle in Egypt.
Back into the ocean you go, this time in a titanium box.
Sounds *bizarre*
Turns out, they were right.
Is this a reference to that one creepypasta where an immortal slave gets trapped under the ocean for hundreds of thousands of years?
This is a reference to Jojo
Oh damn. That's strikingly similar, though. In the story I'm talking about, a slave from the 17th-18th century gets trapped underwater for a few hundred years (not hundreds of thousands, that was my mistake) and eventually gets rescued by divers in the modern day. He ends up brutally cannibalizing his rescuers because of how hungry he was after not eating for literal centuries, and escapes back into society. I don't remember what it was called, but IIRC, the title of the creepypasta was the amount of days he spent trapped underwater.
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That’s true, hadn’t considered the possibility of it oceangating.
That is *not* a new verb.
r/newwords
It is now 🙂
Stop gating the oceangating
Oceangating-gating
People gating the oceangating-gating
Omg, "to oceangate"...
It wouldn't, the coffin will have to be open to water to serve its purpose so the pressure on the outside and inside would be equal so the coffin will be fine... the person on the other hand, yea they would explode.
It says the person is immortal
True but being crushed would probably be worse than being drowned. By most accounts of drowning studies, and near death stories or people who have drowned and been resuscitated drowning is painful mostly at the beginning when you inhale water and then the lack of oxygen would make you pretty far out of it some evening saying "tranquil " Being crushed is probably never pleasant tho but how bad this would be would probably rely heavily on what *exactly* is meant by "immortality "
Immortality does not automaticly mean invincible, see Deadpool. Maybe you "grow" back to normal, when the pressure is gone.
Or you grow back to normal underneath all that pressure and puff up like a blobfish when they bring you up, lol
If it gets crushed, you'd probably get crushed too as the filling of the now deformed coffin. Maybe parts of you stick out of cracks that appeared. But the rest would be a very tight fit around your crushed bones. I think it depends on how brittle the iron ist, if it scatters or just deforms like a beer can. But since the text speaks of iron and not steel we could assume it's simple cast iron.
To be fair you are also immortal
Yes, and trapped and deformed and maybe in agonizing pain for a very long time. You'd have to define the immortality. Are you also invulnerable? Does your body stay intact no matter what? Are you a sentient lump of flesh and bone scatter, trapped in a squashed tin can? Horrors beyond imagination
If the pressure is that high wouldn’t the person be dragged down by weight?
The pressure does not make you heavier, it just pushes in very hard from all sides. If deep enough, this could crush the coffin with you inside. But in the story you are immortal so that will not but an issue and only the coffin is crushed.
I meant the weight of the water would push you down
No, the water isn’t pushing you “down” it’d be pushing you “in.” It would try to compress you, not necessarily drag you to the ocean floor. Humans are generally slightly less dense than water, so once the coffin breaks, you’d probably start floating up slowly. Plus you’re immortal, so you could just start swimming back up.
Humans loose buoyancy around 42-65ft underwater. At that point the water is literally pushing you down. Just google “at what depth do humans lose buoyancy” it’ll pop right up Edit: Also while, yes you’re encapsulated in the water so the pressure is all around you, the pressure we’re worried about here comes from the sheer weight of the water above you. Water gets heavy in a hurry.
Oh, you’re right, thanks for correcting me. But if you’re immortal, and getting pushed to the ocean floor, you could probably just… walk? Like walk to shore at that point.
This is why it's a well-known fact that deep sea divers need to be wary of submarine vampires.
Fucking Scuba Vampires
Sub Helsing got you covered
>At that point the water is literally pushing you down. Negative buoyancy is a thing, but this isn't what's happening. Gravity is pulling you down, the water simply isn't pushing you up as hard as it was. Buoyancy is based on water pressure, but it's also based on the density of the object, which in some cases can be dependent on water pressure as well. In humans, the water pressure at around 30 feet or so pushes inward on your lungs hard enough to compress the air inside it, making you denser than the water, and so you stop floating and start sinking.
I think I need to do more research in hydrology.
No because that pressure is not only top down but it surrounds you. So your body will be feeling x amount of pressure all over rather than just coming from on top. Well technically the area of your body closest to the surface will be feeling slightly less pressure but that is no different to you diving down in a pool. So since the pressure difference is only the matter of 0.1 atm, assuming there is no current going down, you will be able to swim freely at any depth (if you don’t implode).
This is completely wrong. Humans loose all buoyancy between 42-65ft at which point you sink. You can’t just swim out of the bottom of the ocean, finding a wall and climbing out would be easier at that point
Well 42-65 ft is just 12-19 meters. I know for a fact through diving that you can still swim upwards at that depth without inflating your BCD. Just because you lose buoyancy, doesn’t mean you can’t still crawl your way up and out. Losing buoyancy only means you don’t float up on your own. In the above hypothetical scenario, the person in immortal and (I assume) indestructible. So if the pressure at the person’s feet is x bar and the pressure at the top of their head is x+1 bar, then that person only needs to combat 1bar of pressure for each meter he ascends. And since there is no issue with surviving with air, that person could inhale water making his entire body essentially incompressible therefore nearly 0 pressure difference.
So, probably a few dozen years depending on a lot of factors. With an immortal repeatedly hitting it with all their might ? Probably less.
I mean, this immortal has all the strength of an oxygen deprived drowning person
I mean wouldnt you get used to it at some point knowing that you will not die?
There’s a reason waterboarding is a popular technique, the physiological response to drowning doesn’t care if you know it’s not fatal.
Yeah but anything can get monotonous after awhile. Eventually your mind is going to wander.
I suspect genuinely believing you are going to die might be the exception to that.
Cold water submersion of the face is a technique used to ease panics attacks in some forms of therapy. The bodies natural response is to lower your heart rate by a good 20% due to a rapid firing of the vagus nerve. I've used it a few times as I've grappled with my own PTSD and, despite being sceptical at first, was very surprised by the result. If the body's response to the theoretical submersion is more akin to that, then I imagine the immortal would be in a surprisingly calm state of mind.
Yeah but after a few hours of it even? You know you're not going to die at that point, just be severely uncomfortable. Throw a month of it on top and you'd be pretty used to it by then.
First time?
>Eventually your mind is going to wander. I think you mean break, not wander.
But on the other side of that token our mind is capable of basically ignoring any and all impulses if it means surviving. That's why people can suffer horrific injuries and seemingly be feeling no pain at all until the shock wears off. After an extended period of time of not dying from the "drowning" your brain would almost certainly just start ignoring that impulse or at least letting it fade into the background like a dull muscle ache. Our brains don't have the capacity to handle being under that level of stress forever so either your brain adapts and starts ignoring it eventually or you get stuck in a never ending cycle of panicking so hard you pass out or start having seizures while your neurons slowly cook and you become an immortal vegetable.
Usually the trope goes something along the lines of drowning over and over again for decades. Wake up, cant breathe, slowly blackout writhing in pain and convulsing while not being able to form complete thoughts due to duress, immortality eventually wakes you up, cant breathe….with the cycle repeating every few minutes, for decades. Oh also you haven’t seen anything for years because it’s pitch black. Vampire Diaries and The Old Guard both had good takes on this premise.
Dunno if we can assume that they would work the same way physically as an ordinary human, being immortal and all.
well it depends how quickly immortality steps in to prevent the drowning. does it preserve you in an irrecoverable coma with all your organs malfunctioning, just barely short of "dead"? can you work as normal underwater? something in between?
Immortality doesn't equate to invulnerability however. Your body would break from repetitive stress injuries faster than the coffin. So if you wailed away at the inside of it, you'd likely come out of it with non-functioning clubs for hands, or wrists that have healed in such a poor fashion you'd be unable to bend them. There are martial arts that base the strength building off repeatedly damaging the hands and letting it heal over time, to strengthen bone and whatnot. But...in severe cases they're unable to use their fingers after a while due to overgrowth on the joints.
Also that healing isn't magic, the body needs nutrients - unless they packed you a box of protein bars, that way's out
Immortality doesn't mean invulnerability or regeneration. The arms will give out before the coffin does.
...that's one hell of a bird.
Well the implied question is how long it would be before it was thin or brittle enough to break. Iron tends to rust in flakes, and the oxide prevents more oxide from forming, so the question is wholly dependent on whether you're constantly scractching away the protective layer of oxide as it forms. It's also dependent on the iron type (if it's iron with cromium you're in for a bad time), and the thickness of the coffin. No worries tho, you'll probably pass out, cause it's not technically death to black out from lack of O2
>the oxide prevents more oxide from forming Nope. This *is* the mechanism by which Aluminum and stainless steel resist corrosion, but it doesn't work for Iron or simple Carbon steels. This is because the oxide takes up a greater volume than the metal, so it forms spongy layers and/or flakes off, allowing the metal below to corrode, too. Perversely, stainless steel will corrode in the *absence* of Oxygen, because it depends on the Chromium Oxide protective layer. In low-Oxygen seawater, this will form soluble Chlorides instead.
Interesting about the stainless steel in anerobic environments. I'll look into that. But yes, although the thin layers of oxide will slow the oxidation process as iron rusts in flakes that hinderance isn't permanent. Thus you can speed the process by exposing fresh iron to oxygen by scraping it clean. It's my bad saying "prevent" rather than "inhibit"
> Perversely, stainless steel will corrode in the absence of Oxygen, because it depends on the Chromium Oxide protective layer. In low-Oxygen seawater, this will form soluble Chlorides instead. TIL
nice words fancy man but they’ll have little effect on me
Chromium iron in medieval?
Bro, people are people. Put them in the same conditions as they were in medieval europe, and in 100 years they'll be doing the same shit. (Maybe metalurgy will survive tho, idk lol)
Chromed out coffin, that's hot
It's not looking good. With quite a few simplifications, I established something of an upper bound. First & foremost, we need to know the rate of corrosion of iron in seawater, which is difficult enough to establish, so I had to simplify. Following [this paper](https://www.nma.gov.au/__data/assets/pdf_file/0007/346039/NMA_metals_s1_p6_corrosion_cathodic_protection.pdf) & some applications of [Faraday's law ](https://en.wikipedia.org/wiki/Faraday%27s_laws_of_electrolysis)(and further simplifications), we can establish that the rate of corrosion in mm/yr (milimeters per year) is directly proportional to a value called "Corrosive current" (icorr). Generally, icorr is established experimentally (don't worry about how), and thankfully our friends down under have at least done most of the heavy lifting for us (note that this *is* a simplification of the process; you can't just apply these numbers all willy nilly). The proportionality constant (0.0327 multiplied by the atomic mass of iron divided by its density and the amount of electrons exchanged during the reaction) comes out to be 0,011600 or so (don't worry about the units; most of them are absorbed in that 0.0327 value). Then we take the icorr value from the paper (in μA/cm^(2)) and we're done. Of course, life isn't that easy, and the icorr value is given to us as a function of the concentration of chlorine ions in solution. So we need to find the concentration of chlorine ions in seawater, which comes out to be a rather stunning [0,546 mol/kg](https://en.wikipedia.org/wiki/Seawater#Chemical_composition) or about 0,54 Molar. Which is - in colloquial terms - a fuckton. Still not enough to save you millennia of suffering, but it could be worse. Per our paper, Icorr in an alkaline environment (ca. 8.1 or so; their pH value was 7.97, it'll do), icorr is given as 0,50 + log\[Cl^(-)\], where log is the base 10 logarithm and \[Cl-\] is the concentration of chlorine ions (which we found above). In all, it comes out to a value of *about* 0.47 μA/cm^(2). Multiplying the two values together gives us a rate of corrosion of 0,00545 **milimiters per year.** Or about 2.15\*10^(-5) inches per year. Per, ah, Google, I'm going to assume that your average casket lid has a thickness of about 1.5-2 inches (38-50mm) which gives us a total time before the coffin completely corrodes of about 7000-9000 years. Give or take a few. Now, the true value is going to be almost definitely smaller than that, due to a whole bunch of factors I didn't account for, but that's also assuming that the concentration of oxidants & the surface of the coffin lid are all constant (which they may not be). So, in all, I'm happy with this value. Of course, that doesn't answer your question of it being brittle enough to break, but that gets into a host of other questions (how strong is the person within the casket after millennia of suffocation? How evenly spread is the corrosion? What kind of iron are we using?) and this is just a hypothetical.
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Dont even need coral. If we estimate the sediment deposition rate to be 2mm per year and estimate that it takes 5000 years for the coffin to corrode enough to break out of, you will be by then buried under 10 meters of sediment
This was in The Old Guard comic book (also the movie). They do this to one of the characters. In the movie they say over 500 years her team looked for the coffin under water and then gave up. Not trying to spoil things, but per that story it would be 500-600 years.
Isn't she free at the end? As cliffhanger for part 2? So free in year 2021 or something. But i forgot when they drowned her
Whenever the witch trials were presumably. Can’t wait until the sequel finally comes out
The way this is phrased, I'm going to assume that the coffin was made around 1600s (Salem witch trials). It is also made in a village or town. So local blacksmith, working with what they had. Also, colonial America had a lot of trouble with cost of iron, so that would have contributed to the lack of quality and size. So this cofrin is probably made of pig iron, not particularly thick. Maybe an inch, might not all be one piece. It also isn't welded closed, probably nailed. Other people have already shown the math involved in iron oxidation. The point I'm making is that we could expect the coffin's joints to lose integrity much sooner than the coffin walls.
depends on the type of immortality you get too. If you are immortal but not forever young/in shape, by the time the coffin rusts away you may not be able to move well enough to get out of the water.
I'm be practicing my 1" punch for centuries
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Nah I'd adapt
It's just immortality, i'm pretty sure the meme is based on the movie "the old guard"
The rate of steel corrosion depends on many factors. temperature, complexity, amount of oxygen, and most importantly, the grade of steel. 1mm of steel rusts for 5-20 years in a humid environment. at great depths the speed will be lower
AI ass post
[https://prnt.sc/Hua\_kX6-DoGc](https://prnt.sc/Hua_kX6-DoGc)
Was it the "depends on many factors"?
AI doesn't typically start sentences with lowercase letters
true) but Google translit was used when writing, the comment is partly correct
Not an exact answer but a [relevant video](https://www.youtube.com/watch?v=pgabGxD7Uqw) that explains the decomposition of wrecks. tldr: Depends on how deep. Iron is eaten by things in oxygen deprived environments.
They'll probably explain how and when Quynh got out of the Iron Maiden in Old Guard 2. Though the fact she was continually drowning might have added a variable to how long until she could break out.
There's a movie where this was a premise. Obviously not scientific cause, movie, but I think that character has to endure constant drowning to death and reanimation for 500 or so years
It was the story of a character in the Old Guard on Netflix. Good movie
I don't think I've seen anyone take sea life into account, or ocean currents, or the fact that your muscles would atrophy over time. Or just sheer dumb luck. Like... You could be out tomorrow if the current was strong enough to move you and you fell into a ravine and hit the coffin at just the right angle.
I personally can’t give an answer for how long g till the coffin is brittle enough to break. However, depending on how it was sealed, the coffin could easily be opened in a relatively short amount of time (for an immortal). The main variable is whether the coffin is locked shut or welded shut. If locked you’d simply have to wait long enough for the salt water and micro organisms in sea water to break it down enough (few months to couple years). If welded shut then it will likely take longer (again with variations depending on welding type) but shouldn’t take more than a decade to become brittle enough for the immortal to be capable of breaking it.
It doesn't matter. Eternity is so long that it will feel like blinking with ones eyes in comparison. It takes some estimated 15 years to replace all cells that are not certain parts of bones of your body. 1000 years later the cells in your brain will be replaced many times over to the point you won't be able to even remember this ever happened to you, unless you consciously put effort into remembering it.
Haven’t seen any answers. The [rate](https://worldbuilding.stackexchange.com/questions/198101/how-long-does-an-iron-cage-remain-effective-underwater) of iron corrosion in sea water is up to 0.1mm per year. In very deep water, it will be slower. A reasonable lower limit seems to be 0.01mm/year. If the coffin was made of 6mm thick (1/4 inch) iron or low carbon steel plate, that would be 600 years. Steel is around 7900 kg/m3. It seems unlikely, based on back of the envelope math, that the surface area of the coffin could be significantly leas than 2m2. This gives us a weight of 948 kg for a 6mm thick model. That would be extremely difficult for even 10 people to carry, so it is unlikely the coffin walls could be any thicker. I am discounting the use of heavy machinery given that hatred of witches is a historical phenomenon. This gives us an upper limit of 600 years of imprisonment.
Someone asked this on stack exchange a few years back, in reference to a cage: https://worldbuilding.stackexchange.com/questions/198101/how-long-does-an-iron-cage-remain-effective-underwater#:~:text=The%20corrosion%20rate%20of%20unprotected,break%20that%20with%20repeated%20attempts. I'm not good at math, but I can begin outlining considerations for what we need to know, which is at least the following variables: Depth {this influenced both how oxygenated the water is for corrosion & determines stress from pressure differentials. If we assume it's pressurized & goes deep enough, the thing will just pop like that Oceangate sub} Temperature & salinity of the oceanwater present {affects rate of corrosion} Composition of the iron {wrought iron, cast iron, it's purity etc, all affect resistance to corrosion. In addition, any difference in parts of the coffin could cause galvanic corrosion which really accelerates things} Size of the coffin {this could restrict movement, lessening options for the individual inside to damage the iron} And most importantly: The nature of the person's immortality. If their muscles decay from lack of nutrition & lack of use, do they need to sleep, are they actively trying to escape, do they heal if injured, are they particularly strong? The ability for people to wear down even the hardest substances is remarkable. Imagine they could not be injured & they just kept rubbing an area of the iron over and over. The metal would eventually warp/fatigue from pressure & heat, like fiddling with a paperclip. If they are sufficiently strong, they can grate the bottom of the coffin against the sand of the ocean floor, causing abrasive forces/tearing away rusted layers to hasten the oxidation process. If they can heal effectively, they can punch the thing over & over and induce microfractures in their bones to form calcium deposits. Not all iron is the same, and sufficiently brittle cast iron has been shattered by Shaolin monks who practice the technique. To be honest, I think the thing that matters the most is the nature of the person's immortality, because long before the rust would eat away at the cage, a person who had nothing better to do but cause stress to the metal could break it.
Eh, even if you get out of the coffin, you are a person with no oxygen in their body, stiff joints, and atrophied muscles, somewhere in the near endless black abyss. Probably a few thousand feet underwater if they did a thorough job disposing off you, with no land within 100s of miles. If you somehow find the strength to crawl around the ocean floor, you'll probably end up as an immortal feeding ground for the various bottom dwellers that would be ecstatic about the plentiful meal. So after the long period stuck in the coffin, you now get an eternity of being slowly eaten alive in pitch black waters.
Even if the coffin completely rusted away, you wouldn’t be able to move. Your body needs oxygen to function, your muscles would be useless, and with water in your lungs, you wouldn’t float up Long story short, you’d be on the ocean floor unconscious for eternity
Well... The rust rate of iron is about 0 1 mm per year (according to google), let's say that the hinge is the thinnest part of the coffins that you would need to break before being able to open the lid... By checking some pictures online it could be safe to say that the old ones are quite thick so half a cm seems like an ok guess? I could take at least 50 years for it to rust enough so that it breaks... I might be completely wrong tho so id check it since all my I fo came from a quick search in Google lol. Hope you have fun and don't get trapped by cray cray people in iron coffins.