Selects: Cave Diving: Totally Nuts

There are extreme sports and then there is cave diving, the most extreme activity a person can engage in without leaving Earth. Cave divers stay underwater swimming miles into – that’s right – caves, where no human has ever been before. It’s pretty cool. Wade in with Josh and Chuck in this classic episode.

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Episode Transcript

Speaker 1 (00:00):
Hey everyone, it's Josh and for this week's select, I've
chosen our two thousand nineteen episode Cave Diving Totally Nuts,
one of the most apt titles for any of our episodes.
Cave diving is indeed nuts, and you need nerves of
steel or to be utterly careless, because it's one of
the most dangerous activities a person on Earth today could pursue.

(00:20):
But both cave diving and the things that cave divers
do and see are both immensely interesting. So I hope
you enjoy listening to this classic episode as much as
I did. Again, Welcome to Stuff You Should Know, a
production of I Heart Radio. Hello, and welcome to the podcast.

(00:45):
I'm Josh Clark, Nurse Charles W. Danger is his middle name,
even though it begins with W. Bryant. And there's Jerry
Jerome Rolling. We're gonna stick with Jerome, Okay, it's a
good cave diver's name. Yeah, I have just my regular
name because I would never in a million years cave dive,

(01:08):
but I never even scuba dived, I have. Yeah, I
believe that open water stuff. I got really um like,
I guess seasick. Right afterward two and I was convinced
that it had to do with the arrows breathing. I
was like, I'm done, which stinks, because it was really cool.
Breathing underwater is one of the neatest experiences you will

(01:30):
ever have. It's really cool, but not not snorkel Like
you're totally you're underwater and you're breathing. Even if it's pool,
it doesn't matter. Just take like a scuba lesson once
and you'll you'll there, you go, You're done. I have
dreams where I can breathe underwater a lot. But it's
not like, hey, I'm aquaman and I'm just breathing like

(01:51):
a fish or something. It's that I figured out how
to very slowly draw in air, very carefully from the
water around me. It's it's really a strange dream, but
I have it a lot. It's pretty cool. Yeah, I'm
not sure what it means. I don't either. I can't
even begin to guess. But what's more boring than talking

(02:13):
about someone's dreams? They say that nothing is more boring
than that. Yeah, I thought that was a pretty interesting
one though. Thanks. If you're going to talk about your dream,
that's a good one to go with. Um, we're not
talking about your dreams today though, Chuck. Now we're talking
about cave diving, right, which is not a dream. Again,
I'm with you. I don't think it's not for me.
Like I I couldn't even go like regular cavings, which

(02:36):
I did the one time. I can't remember. Did you
enjoy it? I did? It was a butt kicker physically,
very hard work. But I remember describing the pancake thing
that I went through where the you know, I was
laying on my back squirming through in the in the
rock face was three inches above my body and face

(02:57):
and you could you're getting nervous now. I don't even
like hearing about it. Yeah, that was a little weird.
And I'm not even a claustrophobic guy, but I was like,
this is you know, you could die in here. I've
read about a poor guy, maybe the poorest of all time,
well one of them, who was caving with his family,

(03:17):
friends and family and got stuck and ended up dying
his his like they could get to him, they could
move his foot, they could touch his leg legs, but
he was just so stuck that they just couldn't do
anything for him. And so they decided to go home.
He died. No, they were there the whole time, but
he over like I think the course of twenty four hours.

(03:37):
He he just died. The slow she's terrifying death. So
they couldn't They could reach his foot, but not his mouth, clearly, yes,
to give him, you know, nutrients. They tried to give
him stuff through an ivy. I think they tried to
give him a sedative and it kept falling out of
his leg, so they couldn't even do that. Oh gosh,
it was bad. It's hard to even here about, I know.

(04:00):
In but this is cave diving, which is even more
dangerous than caving. Yeah, And there's a couple of a
few types of diving. There's the open water diving that
you were talking about, there's cavern diving, and open water
diving just means, if you know, if you get in trouble,
go up and you'll reach the surface exactly. You're not
gonna get hit in the head by a cave ceiling

(04:22):
right or pinned down through crevasse. No. Cavern diving is
a little different in that you're in a cavern, but
you should be able to see sunlight above you, and
if you go up, you can get your head out
eventually you're from what I saw, the definition is you're
no more than seventy ft deep, okay, and you're within

(04:43):
a hundred and thirty linear feet of the cave mouth
or more specifically, your surroundings are illuminated by daylight. That's
that's really what separates cavern diving from cave diving. It's
kind of like remember a bio speleology episode, So this
would be the twilight zone between the dark zone and
the light zone. That that would be kind of cavern

(05:04):
diving diving in the twilight zone. Right. Then you get
to cave diving, and that is serious business. This is
not uh what's considered recreational diving. Uh, this is going
deep and dark. Yeah with David re Going deep with
David Reese, I haven't spoken to recent a while. I

(05:26):
love that guy. Oh he's a great guy. Yeah, So
this is a technical diving. Can give another definition of
on that Reese joke going deep wasn't good enough. Cave
diving is diving with an overhead environment, so that separates
it from open water environment. Like if if he goes

(05:48):
and panic and swim straight up, you're gonna bonk your head. Yeah,
you might have gone to the under foot um there
and you have no direct vertical access to open air
surface or light. Yeah, this is extremely important. Basically a
horror movie, a nightmare, a living nightmare that you're doing
on purpose that you've paid it a lot of money

(06:09):
to equip yourself for. Um. The light thing is a
really big one too. Like, here's the thing. It's really
easy because you're thinking that this is cave diving and
the word caves in there and we're talking about caves,
but it's scuba diving really, but it's scuba diving inside
a cave. This is a really important thing to not
lose sight of. It's a cave. It's deep in the

(06:30):
bowels of the earth, filled with water. Yes there are
there's no light. There's only light is the light that
you have and you're moving through it underwater. This is
cave diving. I'm in awe of people who do this
and I could watch videos of it all day long. Yeah,
it's very cool to see. Um, it's like scuba plus

(06:51):
as far as the creep factor goes. A read one
article about a guy who is a cave diving researcher
and as we'll see. You know, there's scientific discoveries that
have been made in these caves because just like the
the deep dry caves, the things that live in there
are remarkable. Um. And this guy was sixty nine years

(07:11):
old and still going strong and said his family, you know,
always worries about him, but he super experience, knows what
he's doing. But it's still fraught with danger. I do
have a few death stats if you want. I read
a scientific presentation called thirty years of American cave Diving
Fatalities two thousand fifteen. You got the same one. Huh.

(07:34):
This is by the Divers Alert Network. A hundred and
sixty one divers had died over that. Uh what how
long was that two thirty year period? Uh? Sixty seven
of them were trained, eighty seven were untrained, which is crazy, Like,
I don't know what they're doing down there. To begin
with a fool, yeah if you just take up cave
diving for the first time, but like, yeah, exactly, because

(07:56):
sixty seven trained cave divers pair wished Yeah, and how chuck?
How what was the vast majority? Most common cause was
aphixia due to drowning preceded by running out of breathing gas,
usually after getting lost because of a loss of visibility
caused by suspended silt. And that's where most of these

(08:17):
are in Florida. And that's where I learned about the
silt out. Also from the article you sent about the
UM the cave rescue in Thailand in Thailand, which was
apparently very silty. And a silt out is when so
much silt gets kicked up that it just blacks out
even with your light source. Yeah, the guy that was
in that I think it was an article in Atlantic

(08:39):
UM with the guy knew his name, Robert Layard. I
think he's a cave diving expert, and he said, you
can put your light up to your mask and you
can kind of see your light, but that's it. And
you're in a cave, so you don't know where to go.
Even feeling your way around is not going to help you. UM.
And the problem with the silt out is they can
last for so along in a bad a bad case

(09:02):
of a silt out that you will run out of
air before the silt settles enough for you to see through.
So it's a bad jam. Well, and then this that
you probably read the same interviews, but there's a panic
is what this guy said is what usually happens, even
with an experienced diver, because there's no escape, there's no
quick way out, and things tend to have a domino effect.

(09:25):
So if you're in a silt out, like you said,
it's you try and stay as still as possible, and
it's still maybe not gonna work. You're getting nervous, just
kind of fidgety, now that you've pointed out it's panic
inducing just to think about it, Like you have to
remain perfectly still in the total darkness, and that might

(09:46):
not even be good enough to let that silt stuttle settle.
I I saw um and even a bigger estimate of
the number of deaths from cave diving from the National
Speleological Societies Cave Diving Section. They estimated more than four
hundred deaths in the history of cave diving. But they
said in the world was it just America? Okay? They

(10:12):
placed a lot of them towards the beginning of cave diving,
which took which started in the fifties or sixties. Hey,
I wonder what's in their stage, which is crazy, because
scuba diving started in about the fifties, so within a
little while of somebody inventing scuba diving. Some people were like, oh,
let's go into caves with this stuff. And they started dying,
and so they pointed out like these people didn't give

(10:34):
their lives in vain. Each death was a lesson learned
for everyone else who who um, you know, was yet
to come. But a lot of people died early on,
and it's gotten much. They are far fewer deaths from
cave diving. But it's like you said, they're they're typically
are cave diving experts who are dying because they're pushing
themselves further and further. If you have you know, no

(10:57):
one's cave dive before. Every cave you dive into is
a new exploration, and this is a huge driver for
people who cave dive. This is why they do it.
They're seeing something that no other human on Earth in
most cases, has ever seen in the history of humanity.
They're the first human to be in this place. Um,
there's lots of stuff to discover for when humans were there,

(11:18):
but now it's flooded. Um, there's there's just a lot
of discovery. But as it's been going on for decades now,
every time somebody discovers a new thing. That's one thing
that that is not left to be discovered by everybody else.
So they're pushing themselves further and further. When you cave dive,
you might be a hundred feet under sea level, but

(11:40):
you might be scuba diving for miles down through a
cave system. Not downward necessarily, but horizontal miles um. You know,
round trip for this this cave dive, which is nuts,
but that's that's what they do. I can't remember where
I was going with that. I started to get panicked again.

(12:01):
Have you seen Once upon the Time in Hollywood? Yeah,
you know the scene with Brad Pitt on the boat
in his in that sixty scuba gear. Yeah, it's just
so cool looking. Before we say this, I come from
the future to warn us in the past that we
should add spoiler alert here. That was that. Uh it's
like when they used to call him skin divers. Yes,
what do you think he killed his wife? Uh? Well,

(12:23):
I think that's what you were led to believe. Whether
I felt like it was up in the air well
a little bit. Uh. Also could have been an accident
because he was clearly had that spear gun resting on
his knee pointing at her right. Um. Yeah, the question
is did his neurons fire and make his finger move? Right? Okay,

(12:44):
So we took care of the spoiler that was like
five minutes ago, I know. And now we're back to
cave diving and we should talk a little bit about equipment. Uh.
This A lot of this came from one of our
old House Stuff Works colleagues from the website orld, Buddy
John Fuller, who looks like mc es like. He's been
mentioned twice that he's the tie that binds the Estre

(13:05):
episode and the cave diving episode. Yeah, and some of
this equipment thing isn't the most exciting stuff in the world,
but we should talk about it anyway. I found it
frankly arousing. You got your mask, uh, and this is
something I didn't now. Um. They use sort of simple
black masks because it absorbs light. Yeah, um, which makes sense. Yeah,

(13:27):
because you're using your own light source, so it can
get pretty bright. I saw a flashlight from underwater kinetics.
Maybe it's like fifteen thousand lumens some ridiculous amount of lumens.
Lots of lumens, a lot of lumens um And yeah,
if you have that stuff bouncing all over the place.

(13:48):
You don't want your light, your your you know, gold glitter,
diamond dusted mask like reflecting it in your eyes and
cuts down in visibility. But I take issue with Fuller
saying that they favorite simple masks, because these guys do
like the full face like, yeah, be a mask. Yeah,
not the bread pitt skin diver sixties mask, which I loved. Yeah,

(14:11):
I think I think some of them might, but I
also saw plenty of them. Yeah, have like you know,
I'm trying to think of what they call it, but
just a really cool full face mask. Yeah. It looks
like something that you could dive in a cave in
or go to outer space in. Basically. Yeah. So then
you've got your fins again, black rubber fins. But the

(14:33):
difference here and uh that I gather from this in
open water because you don't want those super long, super
bindy fins because you're trying to not kick up silt,
so you want those shorter, stiffer fins. Uh. And when
you're down there swimming around, you're using little, short controlled kicks. Yeah,
no big sweeping leg movements. No, it's a huge, huge

(14:54):
difference between cave diving and open water diving. The water diving,
your legs are extended out behind and you're fluttering those
um those fins up and down, and you're propelling yourself forward.
In a in cave diving, your bent your legs are
bent at the knees, so your feet are up slightly
above you, and mostly you're making frog kicks, which are

(15:16):
all in the ankle, and you're just kind of waddling
yourself along with these little kicks. You see what I'm saying.
For twelve years, you've been doing little physical gestures of
me like anyone else in the world could see them. Well,
who am I talking to you? But you know that's
the whole point. So the frog look chuck like, this
is what they do, little frog kicks. But in doing

(15:37):
that that you cut down on the potential of um
coming in contact with the rest of the Cave's a
couple of reasons why you want to do that. One,
you want to preserve the cave. If you break off
a stalactite stalactite coming from the ceiling um, that's a
that's nature's work that you just messed with. You don't
want to do that, bro. And then secondly, a lot

(15:59):
of caves pretty much all of them have that silt
sediment on the bottom. That's your enemy. If you kick
it up, you've got a silt out. So you you
want to really be careful what kind of um movement
you're making with your fins, and then just how big
your fins are and how flexible they are, and then
one other thing about that too. You also want to
maintain basically perfect buoyancy where you're completely neutrally buoyant relative

(16:25):
to the top and the bottom of the cave. Yeah.
What do they call the movement? Dragon float? Pulling glide?
Pulling glide float? Yeah, thing you do when you recover
a body. Well, a lot of this is body recovery,
very sadly, um, well, not a lot of it, but
part of search and rescue can very much involve going

(16:47):
deep and getting very swollen, water logged bodies. But yeah,
you pull yourself along with your hand, like in a
little groove by the rock and then just let yourself glide.
It seems very relaxing considering you're doing the most horrifying
thing on the planet. Yeah, so you might do that
even instead of kicking, depending on where the space is,
how tight it is that kind of thing. Also, it

(17:07):
depends on how um uh solid the surroundings are, like
you or anything like that. Um. And then also apparently
you only do that when you have a current. There's
one thing we should say, there's two kinds of cave diving,
spring diving and sump diving. And in spring diving that's

(17:28):
where you see like the pictures in like National Geographic
magazine where it's just this beautiful cave and there's just
two people in scuba gear floating in the middle of it.
That's a spring fed cave where you've got water moving
through it keeping it very clear because there's no way
for sediment to settle because the currents moving to to

(17:48):
um quickly and you use that current to pull and glide.
That looks like something has a little bit more appeal, Yeah,
but I mean it's just as dangerous as anything else.
Like you said, most of the people who die cave
diving die in Florida, and that's what they're doing, is
diving in those springs. That is true, uh. And the
other time the sump kind those are a little more
scary to me. That's a cave system where if you

(18:12):
imagine like kind of like a zigzag like Charlie Brown's shirt. Say,
that's the cave system. Inside of the cave, half of
the bottom half is covered with water that you have
to scuba through, but you also have to climb over
through dry parts in air and then get down to
the to the water again. That's the sump kind of

(18:33):
that's super sentiment and you really got to know what
you're doing there. That's the most dangerous kind by far. Uh.
You have your suit that you're wearing, and you can
wear a wet suit, standard wet suit or a dry suit.
These are not cheap. They cost, you know, several thousand
dollars for a good one. All this equipment is not cheap. Uh.
So it's not the kind of thing that you just

(18:54):
sort of decided to try out, right, So you have
to be wealthy and totally out of your mind to
cave die. Uh. Dry suits are sealed off, so you know,
if you've ever put on a wet suit, part of
the process is getting in that cold water and letting
it fill up your wet suit, which will warm it up.
That's the idea is that water warms. But that process

(19:15):
isn't fun getting in and out of a wet suit
isn't fun neither, to be honest, and it's not that
flouttering nous. You know. We had to wear them when
we Scooba dip with the whales, the whale sharks. It
seems like a hundred years ago. It was easily a
hundred years ago. The dry suits seal off that water,
so you are dry. That's why they call it a

(19:36):
dry suit. Your body doesn't get wet um. And the
cool thing here is that you can layer up some clothing, uh,
and then put on this suit because you can stay warmer.
It's much more pleasant imagining silkies or something. Yeah, I
love the silkies. Uh. And then John makes a good point.
You want to you want to have like extras of
just about everything. Like you don't go down there with

(19:58):
a flashlight. I'd have eight flashlights strapped to every single
limb on my body. Like I'm sure they carry like
an extra I would have a bunch of extra light. Yeah,
you get your little knife if you get snagged, you
cut things. I would have nine knives, eight flashlights. Well,
you do want a redundant amount of stuff, like you

(20:20):
were saying, like you just because if something goes wrong
down there, you are toast unless you can slowly and
deliberately get yourself back to the surface of the ocean.
That's right, that's so yeah. But the other thing you
want to do too is you're in very cramp quarters here,
so everything has to be strapped down pretty closely to

(20:40):
your body or in like a pocket, because you can't
have any stuff hanging down because you'll get tangled up.
I don't want to get tangled up down there. I
know this is kind of amateur hour stuff because we're
not a good breaking point, but we should probably take
an ab break right here. No, I think it's a
great time, and we'll talk about how you breathe down
there right after this. I sk asle sk as. You shouldn't. Sorry, everyone,

(21:21):
I'm so sorry. So you need to breathe down there.
Everyone has seen a scuba tank, um, but it's a
little bit different. It's quite a bit different in fact
than open water diving. UM. You're going to need uh
different things to go that deep, different kinds of air mixtures, uh.

(21:43):
And there are a few different kinds that you can use.
But we should probably talk a little bit about the
bins and what happens to your body. I know we
covered the bens in uh the which one was it?
The what was the old time diving suit called diving bell?
Was a diving bell? I think we cover the bends.
We must have, probably so, yeah, because we've never done

(22:04):
a scuba episode. So John from his original houseof Works
article makes a very great point about pressure and talks
about soda bottles and obviously if you shake up a
soda bottle and then open it really quick, is going
to go everywhere. Or if you're Josh and you've never
in your life apparently opened a tonic bottle soda, I

(22:25):
thought it was tonic, was probably both? Really Yeah, you
got to open those very very slowly every time, no
matter if it's shaken or not. I don't think any
of those are my fault. But um like every backstage
we've ever been to has tonic and soda on the floor,
it would there. I'm cursed with that. But if you
do shake up a soda bottle in the difference between

(22:45):
opening it quickly and very very slowly is can be
related to how the human body reacts under the pressure
of that water. Yeah, so in this case, when you're
scuba diving, opening the cap is analogous to slowly making
your way back up to the surface at a graduated
set of time. They're both decompression basically, is what it is.

(23:07):
And so you could have rapid decompression where your soda
goes everywhere, or your blood vessels burst, or you can
follow these timetables to um to get the nitrogen bubbles
out of your blood. And like you're saying, that's a
big it's a big problem with scuba diving, especially if
you're down below a hundred feet UM for an extended

(23:27):
period of time, the nitrogen um can really build up
in your blood, which can give you the bends. You
can also suffer from nitrogen narcosis, which is bad news
where you apparently feel like you're drunk because of your
because you're intoxicated on nitrogen. Yeah, the same thing can
happen with oxygen. Yeah, um, it's different, but you can
have oxygen what's it called oxygen toxicity? Right, So there's

(23:51):
like if you're just doing like a dive or whatever
and it's like thirty feet of water and you're down
for like a half an hour or something like that,
you're just breathing compressed air like they just took air
out of the air and put it into a tank,
and that's what you're breathing, and you're fine, exactly. So
if you're down for a while and you have this

(24:12):
problem with too much oxygen or too much nitrogen, they
started to get kind of crafty with the stuff that
they put into the tanks. There's something called nitrox which
deals with um the problem of nitrogen arcsis by removing
a certain amount of the nitrogen and replacing it with oxygen,
so with compressed air, with regular air that we breathe
here at sea level. UM it's something like seventy eight

(24:35):
percent nitrogen. Yes, And like Noyen, is that right? I
had them backwards oxygen seventy eight percent nitrogen. In nitrox,
you have something like thirty six percent oxygen and the
rest nitrogen. So because you have far less nitrogen there,
you are susceptible to the bends in nitrogen arc COSI

(24:58):
is less susceptible. Then you would be breathing compressed air,
so you can go down further and you can stay
down longer. But the problem is, like you were saying,
that oxygen toxicity can be an issue too, So they've
come up with you. Even other stuff. Yeah, you can
breathe helium, and there's something called helios seventy helium oxygen.

(25:19):
The weakness here is or I guess the downside is
that you lose body heat six times faster than with
compressed air nitrox. So then you've got to think about
Hypothermias's cold down there, it is cold. And then there's
one called trimex, which is oxygen, nitrogen and helium, and
apparently this is what you use for the deepest dives. Yes,

(25:39):
And it's like all of these things have their pluses
and their minuses. There is no perfect gas, but people
have figured out things like um like if you want
to use helios um, you can stay down longer. You're
not gonna get nitrogen arcosis in your case of the
bends is probably you're less susceptible to the bends because
the nitrogen is not present. But you also can't breathe

(26:02):
that up closer to the surface. There's not enough oxygen
in it, so you have to carry an extra tank
of oxygen or mixed air to to switch to as
you get closer to the surface. That there's like a
lot of different clever things you can do to make
it safer for you to stay down longer and go
further into a cave system when you're diving in it. Yeah,

(26:22):
and the rule of thumb is they go by the
rule of thirds, which I saw it described a little
bit differently than the House of Works article describes it.
The way I saw it was is you want to
make sure you always have two thirds of your tank
left when you're at your deepest part of the dive. Yeah.
I think that's what Fuller's thought. Maybe he just said
it in the way that sounded a little backwards, but yeah,

(26:44):
that's that's the rule though, is if you know you're
going to go to us the very deepest spot you're
going to, you want to only use one third of
your oxygen of your tank mixture to get that far,
because sometimes it can take longer to get get out
than it did to get in, and you want to
be back on the surface with a third left in
your tank basically right. Plus don't forget you're also going

(27:06):
to have to slowly unscrew the cap on the soda bottle.
It takes time, and therefore it takes some of your air,
your gas, and your tank to um to do the
decompression schedule and slowly work your way up to keep
those nitrogen bubbles from um explosively producing in your blood.
How do those tables work? Do you have no idea?

(27:28):
Do you just learn this stuff? You have it like
on your paper? Yeah, I mean obviously not just regularly.
It's laminated. It's laminated, it's basically but you're looking in Yeah,
I'm sure if you're an experienced diver you know those
things back and forth. But because there's such a thing
as nitrogen arcosis or hydrogen, you can breathe hydrogen, but

(27:49):
apparently it has a trippy effect on you too. You
would want to be able to have something to look
at so you're not just relying on your brain. But
they haven't printed out. Yeah, So the idea is like
how much leeway is it? Like you can't go like
don't go ten feet higher or you're in big trouble,
Like it can't be it's not down right, I don't
think it's that, although I suspect that as we advance,

(28:12):
like we'll have it down to the inch and like
by different kinds of people in genetics and stuff like that,
But right now it is I think it isn't graduated
in ten ft or maybe ten meters because that's an atmosphere,
but it says stay at this depth for this amount
of time before moving up ten ms to hang out
for another minute, So I think it's longer than that. Yeah,

(28:35):
And what you're doing is you're allowing the nitrogen that's
dissolved in your blood to turn back into gas, go
to your lungs and then be expiated to be breathed
out by you slowly. That's what you're doing. And so
they figured out that after say ten minutes at thirty meters,
you have removed enough of that blood or that nitrogen

(28:56):
from your blood that you can safely move up to
the next ten meters above and you're neutral. At this point.
You're just hanging out, hanging up, sinking and you're not
rising unless you try to. Know, you have a buoyancy
vest that is is keeping you neutral. Yeah, you're just
hanging out. Yeah, you don't want to rise now if
you're in big trouble and like you're out of air,
you want to make your way to the surface and

(29:17):
just take pressure, you know pressure luck like bens be darned, right,
Like I'm either going to drown or have the bends
and maybe the bens won't kill me, but drowning will
definitely kill me. Even though we learned the drowning is
not necessarily what you think it is. Um, the that's
but if you aren't in any trouble, you want to
go through the decompression schedule, got it? Yeah? I mean,

(29:38):
I just I knew about this stuff, but I've never
really kind of thought about exactly how that worked. I
wonder if we do need to do a Scooba episode now,
maybe maybe not. I mean, what are you doing while
you're waiting around? You're just waiting around looking at the fish,
looking at fish. If you're with you should be with
a buddy. It's tough to communicate unless you have radio, right,

(30:01):
and in which case, if you do have radio, you're
probably listening to XM or something like that instead. But
you can communicate with hand signals or US. Sure, yeah,
you could listen to stuff you should know. It would
be nice. It's a great idea. So let's go back
to traveling. We talked about the grab and pull, the
pulling glide, grabbing float. Uh, you can also have one

(30:23):
of those, and this is what I would totally have
one of those cool little DPVS Driver Propulsion vehicle. It's
the little torpedo looking. It's sort of like a boat
propeller that's enclosed and it just pulls you along. You
just hang onto it and it drags you behind it. Yeah.
I always thought those were really cool. Yeah, they are cool.

(30:43):
They're kind of James BONDI yea very much. But that's
gonna save you from breathing uh more, because you're exerting yourself.
It's gonna save you from just exerting. You know, you're
not gonna be as tired. I mean, think about it,
diving for miles under the Earth's surface, like for miles along.
Even though you're floating, you're still working. Yeah, yeah, that

(31:05):
little kick your your ankles are going to get tired
after a while, your little ankles. Yeah, and that would
help a lot. But I would imagine you really want
to practice on that thing, because if it got away
from you, it's gonna pull you into like a cave
wall or something like that. You're in trouble, kick up
that salt. I would think that little propeller will kick
up salt. I guess if you're not on the bottom,

(31:25):
I think you keep it away from the bottom. All right,
I think we should take another break and we'll talk
about what I think is one of the cooler parts
about this whole thing. Are these guidelines right for this
spoiler alert that we shouldn't know. I would skis watch

(31:52):
sk but you should knows. All right, you're underwater, you're
hundred feet into a cave. It's pitch dark. You've got
your little flashlight, but you need a little trail of
bread crumbs, right, yea more than that. You can get

(32:13):
disoriented down there, even if you're super experienced. So you
need something that says go this way, uh to to
live right, So you have guidelines, like not written guidelines, no, no,
an actual literal guideline right. Um. And they were laid however,
many years before by people who originally explored the cave,

(32:36):
and they the yellow lines or gold lines I'm sorry,
are yellowish and color and they use those as like
the main line through the main parts of the cave. Yeah,
and it's like a little thinner than a rope, but
it's basically a nylon string that is throughout the main tunnels.
Like you said, these little side tunnels are gonna have

(32:56):
white lines if you branch off and you know, you know,
you look at the ler and you know where you
are basically in a side tunnel or the main channel,
and they end within about five to ten feet of
the mainline. Um. That mainline too, doesn't go right to
the top of the entrance, because apparently that is an
invitation for dumb dumbs to say, like, hey, look, let

(33:17):
me see where that leads, right, so they don't even
put them on the surface, no fet from the entrance.
Like you said, Yeah, I saw a really interesting video
from the nineties called a Deceptively Easy Way to Die
And it's like blood on the asphalt, but for cave diving,
it's like an instructional video with recreations and crazy camera
shaking like oh it's out of control. Yeah. Um. And

(33:40):
the guy it's from the the cave Diving chapter of
the National Splunking Society. Um, and like it really like
it is meant to scare you. The guy even says like,
am I scaring you a little bit? Good? It's just
like like like a car safety video, but into with
the song cave diving don't do it right? He? Um?

(34:03):
Is that a Heather's reference? I think? So? Okay? Um,
But he was saying this guy who was astounding, it
was almost like he was a ventrila Chris. He barely
moved his mouth and words were coming out, you gotta
go watch this um. But he was saying, not only
do they not put um like the lines near the
mouths of caves to tempt people. They say, if you're

(34:25):
not an experienced cave diver going on a cave dive,
but you're going to be diving somewhere in the area
of a cave, don't even take a light with you,
just to keep yourself from being tempted, from being like, oh,
I got a light, let me go down in this.
If you don't have a light, even the most foolish
among us probably would not go into a cave. But
if you do have a light, you might try it.
Even if it's not experience that makes sense, But you're

(34:47):
still a dumb dumber to do exactly. Uh. They do
have entry lines though, and that is if you go
to it explore in a cave. It's it's a temporary
line that you do and you this is the one
that you do tie to a big rock on the
surface and then you take that to the main line
that's fifty two feet inside and then everything's all connected.

(35:08):
Because John makes a great point, you've got to be
able to if in the worst case scenario, if it's
dark down there, pull yourself along this line, give the
okay sign to your buddy, um, and you've got to
maybe do this in total darkness with your eyes closed,
so your flashlights off, where it's silty silt out. Yeah,

(35:29):
that's scary stuff. I have the impression that you're kind
of supposed to be hanging on to this guideline basically
all the time, really, yeah, or like pinches away from
it at all times. I would want it within grabbing
distance for sure. Did you read up about the dwarf markers?
I predicted that the dwarf markers existed, because yeah, before

(35:53):
I got to that part, I was like, surely they
have like an arrow. Yeah, it's it's like a plastic
basically arrow on the line saying this way not that way. Well, yeah,
because I mean, if you're in a cave system and
you turn around, you were like, wait a minute, that
doesn't look anything like what I thought I just came through.
Talk about panic. Luckily you have the guideline. Well, which
way is the guideline? Leading you. So that's what these

(36:15):
dwarf markers are, their arrows pointing the way to the
mouth of the cave, the way out. Basically, did you
see the history of the Dorf marker, Because immediate it
was like, why is it called a Dorf marker? It
was just such a weird name. And apparently I got
this from a brief history of the cave diving line
arrow by Alexander Cofield Fief And Uh, there was a

(36:39):
death in nine at Peacock Springs in Florida where pre
doorf marker, and I guess this person died from the
situation you just explained, like went deeper into the cave
instead of on the land. I know. Uh. And a
man named Lewis Holzendorf invented this thing out of duct tape.

(36:59):
So he made these duct tape arrows and they called
him dwarf markers. But because they were Dorf I'm sorry,
because they were tape and all dwarfed up, they would
deteriorate or fold up and not work over time. So
later on flash forward, a man named Forest Wilson invents
these modern dwarf markers, and one of the stipulations he
was like, we gotta call him dwarf markers still, which

(37:20):
is very cool. But these are finally made out of plastic.
It's a plastic triangle you folded over the line and
snap it shut, basically. So thanks to Forest Wilson and
Lewis Holsendorf, the worst case scenario is I'm getting out
of here and you're just going deeper and will never happen.
Forest Wilson told everybody we go out and call him
dwarf markers, and they're like after a Holsendorf. He's like,

(37:43):
who oh man, that's a good dumb joke, a lot
of set up to I just used up a lot
of our air, all right, So you've got these dwarf markers,
they're telling you where to go. You're diving if it's
just a regular sort of and I was about to
call it a recreational dive, but technically it's a technical dive.

(38:04):
But if you're just out there having a good time,
you're probably down there for about an hour or so
at least. But if you're really like doing scientific investigation
or inquiry, or if you're after a body, then you
can be down there for hours and hours doing your thing, right, So, um,
Some of these extraordinarily long cave dives can last into
the double digits of hours, and they'll have tanks placed

(38:28):
along the path. Basically who where tanks? Maybe? All right,
the ghost of Dorff himself is handing these out. Um,
I don't know if he's dead or not yet. Tim Conway,
no Lossdorf. Yeah, I don't think he's with this, Okay, Yeah,
so he's this friendly patron spirit who hands out tanks.

(38:49):
I think, although who knows, he may still be around. Well,
why did you say that you didn't think he was.
I got the idea because someone else developed it and
named it after him, that it was in memorium. I
might have been wrong. No, it's like it's a good point.
At any rate, they'll leave tanks along the way so
you can be like, well, here's my new fresh tank.
It's pretty pretty amazing. But yeah, these the cave dives
can last a very very long time. And like you're saying,

(39:12):
when they're doing this stuff, there probably are being employed
by maybe the National Geographic Society, a museum, uh, some university,
and they're exploring the geology of these caves that no
one has ever seen before. They're also conducting underwater archaeology,
which is a huge new aspect for cave diving because

(39:33):
what they figured out is we've lost a lot of
human settlement um archaeology when the sea levels rose after
you know, eleven thousand years ago and people were running
around in America on the coast more than we realize.
And we're starting to figure that out because of this
cave diving archaeology that's become a thing. Yeah. The uh,

(39:56):
the largest as in longest not deepest um underwater cave
is in Tuloom on the Yucatan Peninsula in Mexico, and they,
I think it was a few years ago, discovered that
two flooded caves actually connected, making it the longest. It's
two hundred and fifteen miles. If these things, you know,

(40:16):
if you go from end to end and and there
are um tons and tons of Mayan like extinct animal
stuff and Mayan artifacts like you were talking about, it
just the waters rose and the stuff just got sucked in. Yeah.
They found the oldest mostly in tech skeleton in North

(40:37):
America in one of those caves, the Hoyo Negro h
It was a woman named Nea and a I A
I believe, Well that's what they named her, and um,
she was from something like a fourteen thousand, five hundred
years ago. Wow, which is way older than the Clovis people.
Can you imagine coming upon that it would be pretty neat. Yeah. Yeah,

(40:59):
but this White cave divers too. Yeah. Yeah, it's one
of the things. The deepest is pretty new as far
as findings go. Well, the deepest in America is Phantom
Springs Cave in Texas, which is chump change at four
hundred and sixty two ft. The deepest now it passed
Italy's Pozzo del Meto. Um. It is in the Czech

(41:21):
Republic on Pazzo demorros uber to this one. The Ranika
propost is deep. It's amazing. And I don't think they've
gone to the bottom. I think they go as far
as they can go, and then I think they drop
a line and measure from there right exactly. Yeah, that's
and apparently dating GPS doesn't work at all in these

(41:44):
cave systems. It's just impenetrable on your own. Um, so
they have to tie off ten ft increments on rope
and just lower it down. That's how they figured out.
The one in the Czech Republic and this is a
big team. This isn't just like alright, we got our
sy system, right. It's like you've got a lot of
people involved in something like this, right, for safety obviously, yeah,

(42:07):
and for some fellowship and for fun. Yeah. The reception
afterward is quite nice. Right, So how do you do this?
How do you get certified? Oh? Well, um, there's a
lot of steps you want to take. You want to
become a basically a professional open water diver first, with
years and years of experience. Yeah, this one guy said
at least fifty dives, yeah, before you even think about

(42:29):
a cave right, um. And then after that you want
to start training for cavern diving. You want to do
that for a couple of years and then right, and
then you start doing cave diving. And one of the
ways they didn't think about this, but it makes sense.
One of the ways you train for cave diving is
doing night diving, taking a night diving course. Yeah, because
there's no yeah, there's no sunlight. There are probably night

(42:52):
diving in caverns or something like that. That's probably kind
of creepy too. Yeah, but once you are a certified
cave diver, you are part of basically the top one
percent of divers in the world. There's this. I saw
an estimate of seventy five professional in the world. Yeah. Um,
so you're part of a very elite group who are

(43:14):
actually exploring, like pushing the limits of human exploration on
Earth right now. Yeah. And I saw the one guy
who was who had um. I think it was a
guy who helped out with the rescuing Thailand, which we
got to talk about. Yeah. I mean he was saying,
you know, this stuff is tough to do because you
think you just go in and retrieve a body, but
it's a crime scene first of all, so you can't

(43:35):
photograph it. So you have to go down there and
first look around and make as many mental notes as
you can to recreate this for an artist perhaps, or
for at least note taking. And uh, he said, it's
really tough emotionally, um, and physically to get the body out.
It's not you gotta be made of tough stuff exactly.

(43:57):
That's it. You didn't have anything else on it. Well,
I wanted to talk about the Thai cave rescue. That's
what we're going on. But the thing is, there weren't
anybody's There was one former Thie seal Navy seal who died,
and because he died, the Thai Navy realized, we don't
have any professional cave divers and stuff. We need to
make this part of our formal training. So now they

(44:19):
do have that. Yeah, But in two thousand and eighteen,
in the summer, you know, the whole world was watching
because these these twelve soccer players and their coach were
hiking along in a cave system that got flooded from
a monsoon and they were trapped in what became a
some cave. And um, just from everything we learned about

(44:40):
cave diving, the idea that they managed to get all
twelve of the soccer players and their coach out to
safety in one of the most treacherous types of caves
you can dive and no one died except for this
one diver is astounding. Man. Yeah, and the one guy
was talking about just how silty was down there, and

(45:01):
uh so you're trying to rescue these people with his
minimal movement as possible, so you're not getting a silt
out conditions. I just where's that movie? It's got to
be coming? Sure? Yeah, yeah, isn't you got anything else? Uh?
Hugh Jackman lead diver. Why not? I got nothing else?

(45:23):
I mean, I guess this last part about regulations is
it's not super highly regulated. You're sort of um dealing
with the local authorities and it sounds like uh like
hazardous or treacherous hiking. You gotta you gotta check in
with an office and usually say this is what I'm doing,
this is where when I'm going in and when I'm
coming out, And you gotta sign that little piece of

(45:46):
paper when you return, otherwise they're gonna come looking for you. Yeah.
But there's also places where you like you can cave
dive all you want, where you just pay a fee.
They just are like, go with God, do your thing.
There's this flooded mine I've talked about before. I don't remember.
It must have been the Abandoned Minds episode in Bond Tear, Missouri.
It's just this a flooded nineteenth century mine like Vogue

(46:09):
could clear water a hundred foot visibility and you just
swim around the mine. Hey, there's Rambo, But was he
in the mine? Yeah? He hit out in the mind
in First Blood. I'll bet we had the same conversation
the Abandoned Minds episode, because I don't recall it. Are
you got anything else? Nope? Well, if you want to
know more about abandoned minds almost said if you wanted

(46:30):
more about cave diving, read about it, probably don't do it. Uh.
And since I said that it's time for listening, oh,
you can read about on how stuff forks even right?
And since I said that it's time for listener, man,
I'm gonna call this one of the follow ups from
our conversion therapy podcast. We got a lot of really
good responses on that and one bad one. Did you

(46:53):
see that guy? I didn't see that one. Now. Yeah,
we had a guy who wrote said he was quitting
us because of our liberal bias. But it was ring
because he says, well, I don't think conversion therapy is
something that works. I do think that homosexuality is a disease.
He's one of those. And h yeah. I wrote it
back and just I was very nice. I was like,
you could probably find podcasts that are better suited for you.

(47:14):
You didn't say, Sionara, no cultural appropriation. Yeah, I just
said good luck to you, sir. That was very classy. Chuck. Yeah. Um.
I always think it's interesting when people write us to
tell us. They're quitting it. Have you ever taken the
time to do I have not. You just quit something, right, Yeah,
keep it to yourself. Maybe, like you know, ran about

(47:36):
it to friends for a little while to get it
off your chest. But like, just so you know, person
prison I've never met. Uh. This is from Jordan's He says, hey, guys,
is a Southern Baptist turned agnostic. I absolutely detest the
acceptance of the garbage psychotherapy pseudo science of CT. Josh

(47:56):
mentioned that have you ever been an early teenager and
late teen ager? You know what it's like to be
sexually confused or curious. When I was between the ages
of fourteen and seventeen, I was called gay or the
F word many times. I did have what some might
consider tell tell signs stereotypically at least associated with being gay.
The bullying and verbal abuse was so intense and frequent

(48:17):
I truly started to question my sexual preferences. That question
was put to bed quite definitely, definitively one night when
a very good male friend of mine and I decided
to experiment some I'll spare the specifics, but I realized
that night this is just was not doing it for me.
But being the good Baptist boy that I was, I
felt guilty about that night, and even though I was

(48:38):
not aroused, it was still a homosexual act. I carried
that guilt with me for many years and through college,
until I realized almost every other male friend of mine
had some kind of experience that they could look back
on and say, this is when I knew I was
straight or gay, or buy or trans or whatever. At
that point, I was finally able to let go of
that guilt, and what a relief that was to my
mental health. I wanted to thank both of you for

(49:01):
making the point that an experience or a feeling you
have in that time of your life should not be
anything to feel guilty about. I didn't know that when
I was, and I was mentally abusive to myself over
a long time. What a shameful is how many people
would use the knowledge of such an act as a
weapon to abuse the person even more Boo hiss. So

(49:22):
to every teenager out there, please don't think there's something
wrong with you because of your curiosity. Embrace yourself. Don't
worry about what your peers or elders may think. You're
perfect the way you are, nice boom. That's from Jordan's
Thanks Jordan. Jordan wasn't even anonymous. Good for you, Jordan's Yeah,
he even drew a little mic dropping right. That was
a great email. Yeah, that's funny. If the guy who
said he wrote in to say he was quitting us,

(49:44):
he's like, oh, cave diving. You get to the listeners
like that's it. He's gonna send us another email. He's like, oh,
this next one is called the gay disease. Maybe I
should listen. Uh, well, that was very nice with Jordan
to shout it out to everybody out there. Rady go
if you want to shout something out to support and
encourage your fellow humans, we love that stuff. You can

(50:07):
go on to stuff you should Know dot com and
send us something on one of our social links. Or
more better, you can go to your email client and
send us an email to stuff Podcasts at iHeart radio
dot com. Stuff you Should Know is a production of
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(50:28):
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