Stuff You Should Know - Keeping Time

Episode Date: January 20, 2026

Today, Chuck and Josh walk you through the history of keeping time, from sticks in the sun to atomic clocks.See omnystudio.com/listener for privacy information.

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of IHeart Radio. Hey, and welcome to the podcast. I'm Josh, and there's Chuck and Jerry's here too, and we're just hanging out, and we decided, hey, let's do some talking about timekeeping, so that's what we're doing today. Yeah, Olivia helped us put this one together. I think the charge was, hey,

how about something on the history of timekeeping without getting two in the weeds about how all of these things work. because that's a whole other thing, like if you want to really break down clocks and watches. But I think she did it just right, the Goldilocks zone, as they say. Oh, nice.

Nice astronomical, cosmological reference there. Well, I think that is a reference for a lot of things, right? Nope, just that. Okay. Where did you get this idea? Because this was when you came up with. You know, man, I don't know. I think I was maybe thinking about a watch on my wrist.

Okay. And then wondering of, or no, Maybe I saw someone had a, what do you call those things? An hourglass. And I was wondering about just hourglasses. And then I started thinking about just, you know, the concept of time and when people started keeping time. And I was kind of had a hunch that I was right that, you know, the need to keep time

didn't come around until much later. So like, as we'll see, early timekeeping was more like seasonal or astrological. and it didn't get to be a thing like, hey, I have an appointment at a certain minute until much, much later. Yeah, but earlier than you'd think, or earlier than I thought, at least. Yeah, agreed. So speaking of timekeeping, you really can kind of say the whole thing just started out with the sun. And one of the neat things about life on Earth is that you can cast a shadow. Most things cast a shadow, with the exception of maybe like amoebae or something like that.

But if you put like a stick in the ground, it's going to cast shadows that move throughout the day. And if you really pay attention to this kind of stuff, you can actually use it to track time throughout the day. And that is almost certainly the earliest way that humans track time. And the stick they put in the ground is widely known as a nomon, G-N-O-M-O-N. I think it means Rod. In Greek, maybe. I also saw that it was slang in Greek for penis. Oh, really?

Yeah. And that just, just... Like, hey, check out the NOMON on that guy? Yeah, almost exactly that. If not that, but just said in ancient Greek. Okay, got you. In Hellenic. Yeah.

But just tracking the shadow that the NOMON cast, hopefully just a stick in the ground. Yeah. That was early timekeeping. Oh, man. I have a thousand jokes. I'm just going to walk right past at this point. Good for you, buddy.

You're a pro. I know. I'm growing up here at 54. So that was, yeah, that's what people use for the longest time. And that eventually, as we'll see, would carry over to things like sundials. But it's no surprise that China was way ahead of the game as far as timekeeping goes because the oldest surviving sort of actual thing that we have comes from northern China, from an archaeological site that they found. found dated back to 2,300 BC. And again, as you'll see, this is a recurring theme, like I mentioned.

It wasn't necessarily like, hey, we got to keep the time from day to day. It's more like, let's calculate the seasons or, you know, the things happening up in the sky. Right. Because it was snowing in the middle of China and somebody said, what season is it? And somebody else said, let's find out with this nomon. And the other person was like, no, no, pull that out. And they're like, no, I mean the stick.

Right. They said, you can get canceled for that. So if you're like, well, that sounds a lot like a sundial. You're right. The thing that sticks up for the sundial is a nomad. There's another version of it that's even earlier than the sundial, it seems, from ancient Egypt called the shadow clock. Yeah.

It's actually really hard to describe. It's much easier to just go look up. But imagine a capital T laying flat on its back on the ground, and it's raised its head and neck up to the, look at its feet. That's essentially... That's kind of perfect, actually. Thank you. I really thought about that one for a while, I have to admit. But the shadow that that crossbar, the top of the T, casts on the rest of the T, over the day, is demarcated. So you can track six hours a day as the sun is rising in the east, and then you turn it around at noon, and then you track the next six hours of

the sun is setting in the west. Pretty spectacular, considering that's close to 3,000 years old. Yeah, for sure. For that descriptor, did it help you that you were laying flat on your back with your neck raised up, looking at your feet? Yeah, sadly, I have to admit that I had to go lay down and figure it out myself.

Okay, that's good. But yes, I was needed to. Nice work. Finally, to the sundial, the first round sundial that we kind of know as a sundial seems like it was created by a Greek philosopher name Anxmander, very cool name, not Alexander, but Anxmander,

of Miletus. This was 6th century BC, but again, probably still tracking seasons at this point. The first sundials out of Greece that actually marked hours, like when people started keeping track of the hourly time, and as we'll see it, you know, it just gets more specific until we eventually,

much later, we'll get to minutes. but the hourly timekeeping started in 350 BCE. Yeah, and then very quickly after that, around 280 BCE, they came up with the hemicycle, which is imagine like a cube block of stone with a basin, a bowl carved out of the middle, and then they managed to cut it perfectly in half so that you just have half of a bowl.

That's a hemicycle, because it turns out all you need is half a bowl to make a sundial like that. And I really do wonder if somebody built a, like that. Like they'd make the one, split it in two, and then all of a sudden they had two hemicycles to sell. I bet. You're getting really good at describing things at this juncture in your career. It took me long enough for almost to year 18. It is, it's dismaying to try to explain something and just make it even more confusing than it was initially. I finally got dismayed enough that I decided to do something about it. And what I did was lay down naked and think

it over. By the way, quick correction, because the listener just wrote in about this, we're about to be at year 19, completed year 18 technically. No, really? Yeah, because year 19 and your 20 are the two next years. Does that make sense? It does, but I feel like it's wrong because started in April 2008 and going to April of 26, that's 18 years. Completed. I see.

Yeah, I should have known. Right when somebody busted out math, I should just been like, yeah, that's right. The cool thing about the hemicycle, besides the fact that people back then probably said, is that thing a hemie when they walked by? You know, it couldn't resist that one. But they knew at that point, it was a pretty smart thing,

that the sun's position changes over the course of the year, over the course of those seasons, obviously shorter winter hours, which we're going to get to. but they accounted for that. They had sundials that would show the time using multiple arcs carved into the hemisphere to account for that sun changing over the course of the year. Yeah, so like the lines of the hours went up like longitude, and then the seasons were like latitude.

And I guess just depending on how high up or how shallow the shadows were, you could tell what season it was, because it was within one of those arcs or two of those arcs or three or four, right? Yeah. And, you know, I mentioned the seasonal hours. When Greek sundials started dividing daytime into 12 equal parts, obviously not hours because we eventually ended up at 24, like not hours as we know it. But they would depend on the length of the season.

So it's not like they accounted for it. So they were all uniform. It was just like, hey, sometimes during the year what they will one day call an hour as longer than others, which would lead to some kind of a cool thing where ancient texts in Greece would refer to that, like a winter hour or something that could be done in a shorter amount of time. Like, that'll just take you a winter hour. Yeah. And this was, so this was the ancient Greeks. This lasted well into the medieval period. That's how people did hours. The hour was longer in the summer. The hour was shorter in the winter. And it was essentially their way of what we do for daylight savings time by

adjusting. Yeah, except we're just, you know, modern humans are way too anal to just let it kind of flow like that. Still got to be exact. You know? Right. Right. Okay, so you got the sundial and everybody was like, well, we move around a lot and not every place has a sundial, but I always want to know what time it is. And what humans do is take a technology and figure out how to shrink it down into a portable size. And they did that with sundials too, usually made of bronze. And because they were mobile, they would also have settings and often instructions on how to adjust it depending on where you were in the world. Like some of the ancient. ancient ones that have been found have like just put it to this setting if you're in Constantinople or put it in this setting if you're in Luxor, right? And then other ones you kind of have to figure it out a little more based on latitude. But they were portable and essentially they were like pocket watches but amazing bronze spheres sometimes.

Yeah. So like once they could do that, they would hang it facing the sun so that that little pointers, I guess it was it still called a nomon at this point? I would think so. I think some people still call them no mons when they're referring to sundials. Yeah, I think you're right. But they would face the sun so that that pointer's shadow would hit the correct hour. Later on, they had different types that had like a pinhole that let the beam of sunlight come through and actually shine a mark on the hour, which was like super advanced at the time.

Yeah, it was like the staff of raw model. Oh, yeah. So there was a big reason that people were keeping track of the hour. in ancient Rome, especially by the time Rome came around, it wasn't necessarily to keep appointments, although they certainly had that kind of thing or to keep time on stuff. One of the big things over the years in different cultures, it turns out, was they needed to time things, especially for something like drawing water. Like water was a communal resource, and everyone had a certain allotment, and they would divvy up those allotments, not by measuring how much water was

taken up. But take as much water as you can within this, you know, before this beam of sunlight reaches this little line, essentially, right? Yeah, yeah. But in Rome, they had an extra reason for it. And that was because the hours of every single day, or the first 12 hours of every single day, because it wasn't initially that they were also like, let's track the nighttime, too. They just tracked from sunrise to sunset typically. Yeah. Each of those hours was associated by, with the different astrological sign. It was called planetary hours. And it was because,

so you could maximize whoever you are worshipping. So like if you were worshipping Celine, the moon goddess, you wanted to do that three hours after sunrise on Monday. And so you would use some sort of timekeeping device to keep track of that. Yeah. And the same, of course, is true in Islam. Once that became a big thing,

the Muslims adopted sundials because they're, you know, have to pray. at different increments at different times. So it was really to kind of keep up with their prayer hours. And they are the ones who came up with, like if you have a sundial in your garden as a little thing, which we have one of those. I bought one for Emily a few years ago.

Cute. That kind of sundial is what the Muslims came up with. The one that's got the flat circular base and that no-mon is, am I saying that right? Yeah. The nomon is parallel to the polar axis of the planet Earth. Yeah, they also laid trigonometry on the whole thing and came up with a bunch of different kinds of sundials.

There's one that was conical. And remember the hemicycle? Imagine taking that and just kind of squishing the bowl and adjusting it at an angle. That's what a conical sundial is. They look amazingly cool. So I say look one of those up. And then finally, I think before we break,

we should give a shout out to early 13th century Moroccan mathematician. Abu al-Hazan al-Marakushi, because this is the dude that was finally like, you know what, uniform hours is where it's at. And we should start kind of keeping track of this stuff in a uniform way, like actual real timekeeping, and that kind of spread out all over the world from there. Very nice.

Yeah. All right, well, let's take that break then. It's time. All right. We'll be right back. I'm John Polk. For years, I was the poster boy of the conversion therapy movement. The ex-gay who married an ex-lesbian and traveled the world telling my story of how I changed my sexuality from gay to straight. Once upon a time, I was on 60 Minutes, Oprah, the front cover of Newsweek.

And you might have heard my story, but you've never. never heard the real story. So join me as I peel back the layers and expose what happened to me in the midst of conversion therapy to shine a light on what the X-game movement does to people and the pain it continues to cause. I had lost 150 pounds because if I couldn't control my sexuality I was going to control my weight. It sounded like, and this is the word I used, a cult. And as I look too at the harm I did from within. Listen to Atonement, the John Polk story on the IHeart Radio app, Apple Podcasts, or wherever you get your podcasts. What if mind control is real?

If you could control the behavior of anybody around you, what kind of life would you have? Can you hypnotically persuade someone to buy a car? When you look at your car, you're going to become overwhelmed with such good feelings. Can you hypnotize someone into sleeping with you? I gave her some suggestions to be sexually aroused. Can you get someone to join your cult? NLP was used on me to access my subconscious. NLP, aka neurolinguistic programming, is a blend of hypnosis, linguistics, and psychology.

Fans say it's like finally getting a user manual for your brain. It's about engineering consciousness. Mind games is the story of NLP. It's crazy cast of disciples and the fake doctor who invented it at a new age commune and sold it to guys in suits. He stood trial for murder and got acquitted. The biggest mind game of all, NLP, might actually work. This is wild.

Listen to Mind Games on the IHeart Radio app, Apple Podcasts, or wherever you get your podcasts. New Year, new goals, and in this economy, a better money plan is more necessary than ever. I am Matt. And I'm Joel. We are from the How to Money podcast. And every week, we help you to spend smarter, save more, and make sense of what's going on out there. If you want 2026 to be the year you finally feel in control of your money, we're here to give you the tools and advice to help you make it happen.

Listen to how to money on the IHeartRadio app, Apple Podcasts, or wherever you get your podcasts. Okay, Chuck, so we're back. And before we move on, I want to say that I finally got it, Reggie Watts. A regi Watt. Did you listen to it in QA? Yeah, when I was QAing it, I got it. And I was like, man, that zoomed right past me. Well, you were in a thought, and I slipped it in there very stealthily.

It was very great. All right, nice little treat for you. We're talking about the National Radio Quiet Zone episode, by the way, everybody. That's right. So you got sundials. Next thing that we moved on to is water. That's right. A bunch of different cultures came up with water clocks.

It's not clear if, again, it started in China and moved to Greece and then moved to the Muslim countries. Who knows? But it's also possible that people came up with this. There were just so many things available to you, to use, to try to keep track of time. And there were really simple water clocks. Water was eventually used to run mechanical clocks. But the first ones essentially were like almost hourglasses made of water. Yeah. I mean, essentially what you're doing is you're either keeping track of time by water draining out of something that's marked by increments or filling something up that's marked by

increments, right? Yeah, pretty much. I mean, that's essentially it. And you could supplement sundials with these because on a sundial, if it was really overcast, you had no idea what time it was. At night, these things worked as well. Really, there were two problems with them. One was that they would freeze if it was freezing. Your water clock probably wouldn't work quite as well.

And then also, the viscosity of water can change depending on variables like temperature and stuff like that. So they were entirely accurate or reliable all the time. But they did the trick for enough time that people started to improve on them and add different kind of engineering principles like floats and valves and siphons to regulate water more accurately. Yeah. I wonder if there was ever like, sorry, I'm late, you know, we had a cold snap, my water clock froze.

Like, you've got to move those things inside, buddy. I guarantee somebody use that excuse. Yeah, for sure. But because of the issues with water and temperature and stuff like that, mercury became a pretty reliable substitute. This was in 10th century CE, and it was a Chinese engineer who figured this out. And that basically, you know, solved a lot of the problems because mercury wouldn't freeze. It wouldn't have different viscosity at different temperatures,

and it would ensure that you're on time to that appointment. Yeah. And that engineer was Zhang Si-June. I need to show off. I was just going to walk right past that. Here's my favorite kind of early. Oh, me too. Is it?

Yeah, I'm not surprised. Incense clocks. Yeah, and I'm not even into incense anymore. I was in college, I think, like most people are. Same here. I used to burn some frankincense, man. Yeah, me too. But I really love this one.

This existed in China, at least since the 6th century C.E. Also in other parts of Asia and Korea and Japan, for sure. But it's, I love the idea because essentially it's, it's almost like a fuse. And as we'll see, it sometimes was a literal fuse. But incense was burned and used as a timer. Like how quickly does that thing burn down and stop burning? Yeah. The coolest ones, though, were incense clocks that were like a box.

And it was essentially like an intricate maze that you would pack with incense and then light it. And there were different, I guess, stencils that you put on top of the box. to create different times. So like if you wanted an hour, there was a very simple maze. If you wanted the whole night, it was a much more intricate maze. And that's another thing I would say to look up.

There's a lot of stuff you should go and look up throughout this episode, and incense clocks are definitely one of them. Yeah, but I'm glad you saved this one for me because I think it's the coolest part about all of the incense clock stuff is that they had different scents. And it just makes sense over the course of a night

where you could smell the time. So you knew when a certain smell came up what time it was, which I think is super ingenious in its simplicity. And also like, you know, you know what happens at Sandelwood time. The sexiest time. Yeah, I've got jokes that I'm keeping it myself.

Yeah, good. There were also alarm clocks. You could use the heat from an incense stick, I guess, or whatever, to basically burn through a thread. and drop a bunch of, like, bells or something into a metal dish, that'll wake you up for sure every time. And apparently Chinese messengers would take incense and light one end and put the other end between their toes and wake themselves up like that, which is, man, just drink a bunch of water. That's all you need to do. Don't burn your toes.

Yeah, that's true. But like I said, that's like literally lighting a fuse and it, like, you know, you get the hot foot and you know, it's time to get up and deliver the mail or whatever. That's right. We also have candle clocks that came along. This is the medieval era. Notably, Alfred the Great, supposedly would get his day together and time it by six candles. Each would burn for about four hours, so six times four, 24. Yeah, you could also take, say, a four-hour candle and break it, like, just mark equal lines across it and basically keep track of time like that, too.

Then there's astrolabes. I'm not even going to try to really describe an astrolabe. Go look those up. They are incredibly intricate mechanically. They were invented by Muslims in, I think, the sixth century CE. So it's just amazing that they were able to do this. And astrolabes were used at sea until the sexton came along about a thousand years later, essentially. That's how effective they were.

But you could navigate with them. You could survey with them. You could also keep time with them because you just adjust the astrolabe to mimic the stars. or something like that, and you can be like, oh, it's 2.30. It's sandalwood time. That's right. It's sandalwood time. Then we finally get to the hourglass, but later than you think, and especially, and I'm glad Livia dug deep because she's a great researcher, but if you just sort of do cursory internet research,

you might find a lot of people saying it's ancient Egypt. But that's probably not the case. It's actually much later than that, probably the late medieval period that hourglasses came along. and actually after the mechanical clock. That's nuts. The earliest known reference is in Italy in 1338, and you think an hourglass is pretty easy to make. Like, you know, you just blow the glass in a certain way

and throw the sand in there. But sand is finicky, as you know, as far as humidity and moisture goes. So you had to get the sand in there, and you had to seal it up, but you couldn't seal it up with any kind of moisture because it would clump up. So it's a little trickier to make an hourglass

than you might imagine. Yeah. When it's humid out, the soap opera days of our lives never gets started. Right. It's sad. Was that the one you watched in college? I think that's what people wrote in and said, yeah, I'm pretty sure. I couldn't remember. Okay. So one of the other things humans do when they have an invention that's popular and widespread, they don't just shrink it down to a miniature portable size. They also just show off. Yeah. They do whatever they can to make it even cooler. And there were a...

succession of inventors in different parts of the world over the years that did some really neat stuff with, say, like, water clocks. One was a guy named Andronikos. He was from Macedonia. And he built what's called the Tower of Winds in Athens. It's this, I think, hexagon or octagon made of marble that's 15 meters or about 45 feet tall, still standing. But when it was in use, it had water clocks, it had sundials, you could gauge the wind, you could tell what was going on celestially. He just basically packed every needo timekeeping invention that was around at the time time into this thing. Yeah, and like you said, a lot of people just started getting just sort of fancy with it and actually just really creative. In 8th century CE, there was a Chinese Buddhist monk

who along with his colleagues created a clock that was a water-powered wheel. had a gear system. This is when gears really started becoming a huge thing in timekeeping. Yeah. And it did a single rotation every 24 hours, which you think like,

all right, that just sounds sort of regular. But it also had like bells chiming on the hour and it had a drumbeat that chimed every quarter hour. So this is when like kind of hearing chimes and things to tell you what time it was came in. It went buntit every 15.

That's right. There's a guy named Su-Sung who is very famous for his 35 foot. I also saw it described as 40 foot clock tower. One of the things it did were there were mannequins that came out and rang gongs. You usually associate this with like maybe some sort of cuckoo clock or something like that. This is from the 11th century. So it's pretty pretty impressive that he came up with this. And again, it was a water clock. Like this is running on water. And then someone else who put water clocks to great use was a just this amazing

inventor and engineer. His name was Ismail Al-Jazzari. He was from Upper Mesopotamia. And his whole thing was not just accurate clock timekeeping, but just essentially delightful little add-ons that did some cool stuff. He created what's called the Castle Clock. That's pretty neat. But for my money, look up the Elephant Clock. There's a life-size replica of it at a museum, I think, in Saudi Arabia. and you can see, you know, how it works and what it does, but essentially water just moves from part to part. There's a scribe in the middle riding on the elephant. There's another person on the front of the elephant driving it.

There's another guy way up that plays symbols and stuff. It's just amazing, especially when you learn about how every single step works. Yeah, that thing, you sent that to me. That was super cool looking. Yeah, very ornate. Now we kind of get to the point, should we break or? can we keep going? Yeah, let's take a break. All right, we'll be right back.

Learn some stuff with Joshua and Charles. I'm John Polk. For years, I was the poster boy of the conversion therapy movement, the ex-gay who married an ex-lesbian and traveled the world telling my story of how I changed my sexuality from gay to straight. Once upon a time I was on 60 minutes, Oprah, the front cover of Newsweek. And you might have heard my story, but you've never heard the real story. So join me as I peel back the layers and expose what happened to me in the midst of conversion therapy. To shine a light on what the X-game movement does to people, and the pain it continues to cause.

I had lost 150 pounds because if I couldn't control my sexuality, I was going to control my weight. It sounded like, and this is the word I used, a cult. And as I look, too, at the harm I did from within it. Listen to Atonement, the John Polk story on the IHeart Radio app, Apple Podcasts, or wherever you get your podcasts. What if mind control is real? If you could control the behavior of anybody around you, what kind of life would you have? Can you hypnotically persuade someone to buy a car? When you look at your car, you're going to become overwhelmed with something.

such good feelings. Can you hypnotize someone into sleeping with you? I gave her some suggestions to be sexually aroused. Can you get someone to join your cult? NLP was used on me to access my subconscious. NLP, aka neurolinguistic programming, is a blend of hypnosis, linguistics, and psychology. Fans say it's like finally getting a user manual for your brain.

It's about engineering consciousness. Mind games is the story of NLP. It's crazy cast of disciples. and the fake doctor who invented it at a new age commune and sold it to guys in suits. He stood trial for murder and got acquitted. The biggest mind game of all, NLP, might actually work. This is wild. Listen to Mind Games on the Iheart radio app, Apple Podcasts, or wherever you get your podcasts.

New Year, new goals, and in this economy, a better money plan is more necessary than ever. I am Matt, and I'm Joel. We are from the How to Money podcast And every week we help you to spend smarter, save more, and make sense of what's going on out there. If you want 2026 to be the year you finally feel in control of your money, we're here to give you the tools and advice to help you make it happen. Listen to How to Money on the IHeartRadio app, Apple Podcasts,

or wherever you get your podcasts. All right. So we're back to wrap it up on clocks and eventually, spoiler watches. But we're at the point now where clocks kind of start ticking. getting closer and closer to keeping track of seconds, although that'll be a second until we get to it. But as for mechanical clocks go, those water-powered Chinese clocks arguably were the first mechanical clocks. And again, it's one of those things where they don't know if people invented

these in Europe or their Muslim world at the same time, or if it kind of spread out from one place to another origin story is maybe mechanical clocks came from Europe with, is it, would it be Gerbert? I think so. Gerbert of Aralak, who was a French scholar, but you might know him a little better as Pope Sylvester the second.

Oh, okay. Because he would become Pope later on. He developed, I guess in his pre-Pope days, a mechanical timekeeping device, like truly mechanical in 996 CE, but then it took a few hundred years for it to become,

like for mechanical clocks to become a real thing. It didn't really catch on. Right, which makes some people suspect that he might not have actually done that. Yeah. So what's happened here, I guess, we've transitioned from tracking the movement of water to track time to actually using the kinetic energy in water that's, say, flowing downhill to run gears and stuff like that.

Those are the mechanical time devices that were, that were some of the original mechanical ones. It's like the Chinese came up with this a very long time ago. When Europe got involved, they removed water to run gears and replaced them with weights. But it's the same principle at work. Like if you hold a weight up on a rope and let it fall down, gravity's going to pull it toward the earth. And it's releasing kinetic energy. If you can control its descent, you can use that to turn gears and to keep track of time

in a very specific way. I mean, it's not nearly as accurate as anything we track time with today, but it was still pretty impressive that they were making these in like the 13th century. Yeah, for sure. There was a monk in 1271 named Roberta's Anglicus, who he talked about, there was actually a Latin term, horologia, which is the Latin term for time measuring device. And they were using weights to turn wheels like exactly one time,

over the course of one day. And again, they would get kind of break that down and get more specific as they learn more about gears and how the weights work. But, you know, the weights, if you look at a grandfather clock or a cuckoo clock, like these things all have, and we'll get to the pendulums, not only pendulums in a grandfather clock, but it's weights

that are still operating this thing. Yeah. And one of the inventions that really kind of, it was a game changer, it's called the Virgin Foliot mechanism. And essentially, you remember in karate kid two where all of those Okinawan villagers are sitting there playing their hand drums? Yeah, yeah. Okay.

So that's essentially a verge and a foliot, kind of. Imagine the drum part is the, I think, foliot and the verge is the handle. And when there's like a crown wheel, the gear, the main gear that operates a clock, when it turns, it turns the foliot. and the foliot turns like slowly one way and then slowly back another and when it moves back in position the gear's allowed to turn. So you're actually controlling the kinetic energy

of those weights that's falling and making the whole thing move and by doing that in a precise way that's how you can keep track of time. Yeah, and you know, it stays constant because that thing is constantly stopping and starting so it's going to keep that weight from picking up momentum as it goes down and descends.

So that's how you get the constant, speed, and that's also how you can create a ticking sound. It's just that little, you know, constant intermittent movement. Yeah, but you wouldn't, it doesn't move like an Okinawan hand drum moves. I mean, it moves not as fast, I should say. That'd be, it'd be out of control clock. Yeah, and didn't that drum move faster and faster, the more intense that the scenes got in that movie? Yeah?

Oh, yeah. Man, it really helped build the suspense, I think, during the main fight, maybe. Yeah, I mean, this is a pretty smart device for a movie It was a good sequel. As far as sequels go, it was, they didn't just, you know, build on the last one. They really kind of went all out and recreating things. Yeah, and one of the great bad movies of all time, and I'm lobbying to get on a friend of the show The Flop House,

the best bad movie podcast out there, in my opinion, to do Karate Kid 3, which is hugely entertaining as a bad movie. Is that even worse than Jaden Smith? Myths Karate Kid? Because I heard that was pretty bad. I didn't see it, but Karate Kid 3 is... Oh man. If you're into a fun, bad movie to watch with people, Crotty Kid 3 is one. And that was one where... I thought I talked about it on the show at some point, but where, God, Ruby was probably like six years old and came up with, like,

legit, her first quality joke watching that movie. Can you share it? I don't know if it would translate. I'll tell you later. Okay, that's fine. But good for her. Six is a good age to come up with a quality joke. Bye. Actually, I think I could, actually.

There's a recurring thing in that movie that happens where every time the bad guys come into a place, they turn a light off. Like they'll come into a warehouse to fight and they turn the light off. It happened like two or three times. And I kept going like, what is going on? It's so weird. And then later in the movie, they rush out and find Daniel Son and Miyagi in a forest. And Ruby said, that'd be funny if they reached over to a... tree and turn the moon off.

That's good. That is a quality joke. It's a pretty good joke. Yeah. Yeah, I haven't seen the Karate Kid 3. I know of it. I know Hillary Swank's the Karate Kid in that one. No, no, no, no, no.

Well, maybe I'm getting the number wrong. Karate Kid 3 was actually Daniel and Miyagi still. Oh, was it? Yeah. Unless I have it out of order, but I know it's not the Hillary Swank one, obviously. Okay. All right. Yeah.

So it's either three or three. for. Well, I haven't seen the one you're talking about either. I don't remember anybody turning off any lights anywhere. Yeah, it's truly bad in a great way. Okay. So, um, just, back to clocks. Just like in the Muslim world, um, timekeeping pieces in Europe were initially to, to, um, keep people on track for daily prayers. Apparently monks and monasteries prayed seven times a day, but there were also meals. There was also beer brewing time. Um, and so these, these early clocks, using the virgin foliot mechanism in weights, they help keep the monks on track.

Monks are associated with churches, so very soon after that, churches started keeping clocks as well. And fun fact, one of the reasons that churches often have very, very tall steeples, often with bells on top, is because those used to be parts of the clock. To run a clock so big that it can ring that bell, you need to have very heavy weights that are coming. and descending from a very high place.

Yeah, for sure. Nice little factoid there. I love that one. And the oldest surviving mechanical clock is in a church. It was built for the Salisbury Cathedral. That was in 1386. But these clocks didn't have a face yet. It was still, you know, like ringing a bell kind of thing to know what time it was.

And in fact, the word clock comes from the French word, is it? cloche, I guess. Like that glass thing, dome you put over stuff? Yeah, which is a bell. But, you know, it wasn't too long after that that they said, hey, if we can have a clock turning gears, how hard would it be to actually put a sundial kind of like thing on the front of it and turn the gears of a hand so people could actually see what time it was? And they went, eh, not that hard.

We can do that. They're like, are you talking about a moving nomon? and the monks said, that's exactly what I'm talking about. That's right. So there's this really interesting take on all that. The fact that clocks started tracking time in monasteries and then churches and the cities that were built around churches would all hear the bell. So people knew what time it was all of a sudden. It wasn't like the sky is purple, so I better milk the cows.

It was like, oh, it's one in the afternoon, so I better milk the cows, right? because apparently this guy would turn purple at one in the afternoon in medieval Europe. And there's a philosopher named Louis Mumford. I think he was working in the 1930s. And he says that, that is the birth of the modern era, not steam power that came hundreds of years later. Removing people from the rhythms, the natural rhythms of the day and imposing time on them. All of a sudden you could be like, be at my blacksmiths, at three or else you're fired, you know?

Yeah. What a drag. Exactly. I think that's a really good case that he makes. Yeah. No, totally. I mean, it was a real game changer, and that's when everyone got a little bit more uptight, I imagine.

I imagine as well. You know, and we still didn't have minutes at this point. Like those clocks that we were talking about, you know, grinding those gears around, you could still have a, you know, a decent hour as far as accuracy goes. the word minute actually to mean what we meant it didn't even come around until the late 14th century so minutes are a relatively modern thing if you consider 14th century modern right um and thanks for let me take that lewis mumford little tidbit oh yeah did you like that one i love it it's almost as good as the um the different smells of incense yeah well you know we like to scratch each other's

back. Another joke skipped. So you can take weights and their kinetic energy and really now you can do, you can take anything that has kinetic energy and use it to control its release and you can use that to do things like drive gears and things like that and you can use those gears to keep time with. Well, a coiled spring has a lot of kinetic energy and replacing the weights and clocks with coiled springs meant they became portable because of course humans love to make things portable.

Yeah, but they were still pretty inexact because friction is a thing. So depending on like how well it's made, how well it was lubricated, if it was hot, if it was humid, that would that would make just change the way clocks work. So they were still pretty inexact at this point. So sundials were still kind of preferred water clocks were still preferred for a long time and actually more precise. if you really want to jump forward in precision, you can look no further than Galileo Galilei and the turn of the 17th century. And he was the one that kind of came up with this idea of a pendulum

when he started measuring the movement of lamps swinging on a cord using his own pulse beat as a reference. Pretty cool. Yeah, so he found like you can use a pendulum to keep time. The reason why is a pendulum swing is divided in exactly in half time-wise, right? So that's what's called a harmonious oscillator. Each swing to the left or the right is the exact same amount of time.

And even more than that, when a pendulum loses energy, that doesn't change. The arcs just get a little shorter, but they're still equal to one another, right? So Galileo figured out that you could use that information to build the clock. He developed a clock. He never built it because he kept,

being called away by the Indigo girls to help them get through life. So he wasn't able to build it. His son started to build it, but as Galileo always said, that boy never finished anything that he started, so he didn't complete it. And finally, in 1656, the Dutch mathematician Christian Hugans,

the son Galileo always wanted, he ended up creating that clock, the first pendulum clock that Galileo had kind of come up with. Yeah, that was in 1656, and almost right after that, there was an English scientist named Robert Hook with an E of the end, said, you know what, I can make that thing better. And he replaced the verge with, you know, that we mentioned earlier, with a something called an anchor escapement, which was just a new mechanism to regulate the swing, I guess. But that allowed the arc of the pendulum to be reduced from about a hundred, I'm sorry, a hundred degree swing to four to six, degrees, which again, meant you could pack it in a packageable size. Yeah.

And also, they found that less of a swing, they found that the less wide the arc, the more accurate, the timekeeping was. Anchor escapements are almost impossible to explain unless you see it actually happening. And they're like, oh, okay, that totally makes sense. But I say go look up a video of how anchor escapements work, because it's pretty amazing. And so because you have slower moving pendulums, they require less power, which means you need less weight. And eventually there was a guy named William Clement who put all of this stuff together. And in 1680 came up with what we now call grandfather clocks.

And because of everything that kind of developed from Galileo on, Clement was able to add a minute hand. And now all of a sudden, you knew what minute it was of the hour. Thanks to William Clement. That's right. And of course, you're referring to the long-case clock. It didn't get the name Grandfather Clock until 1820, I'm sorry, 1876. And that's actually from a song called My Grandfather's Clock. That's where it's about, I mean, it's kind of a sad song about a clock that this

guy had who, or his grandfather had and quit working when he died. And it was a really popular song. So Long Case Clocks became my grandfather's clock. and the singer and I think writer was a guy named Henry Clay not Henry Clay people but Henry Clay work You know that's a redux

of our first short stuff I thought we had talked about that right That was the very short short stuff Yeah grandfather clocks Man So pendulum clocks everyone said this is great I love these long case slash grandfather clocks

But finally in the 20s people had figured out, I guess, centuries before in the 19th century, a century before, that you could keep time with a crystal. They produced reliable oscillations that you could track for time, and people figured out how to use that on watches. For that, I would say go listen to our atomic clock episode. Yeah, that was a good one. From crystal quartz came atomic clocks,

and from atomic clocks came things like GPS. It's how your iPhone or, you know, Google phone keeps track of the time, knows exactly what time it is, thanks to an atomic clock. So we went from sun to water to pendulums to crystals to atoms. That's right. And by the way, I bet I made that same dumb Henry Clay joke in that short stuff, didn't I? I'll have to go back and listen, but any time you get a chance to mention Henry Clay people, you do. And I support it fully.

Of course. For those of you don't know, Henry Clay People was a great band and friends of the show from our good pals, Joey and Andy Seara, the brothers, musical brothers, screenwriting brothers, and they did the theme song

to the stuff you should know a TV show. That's right. It was a great theme song. Very catchy. And they're still great friends. I see Joey all the time because he lives in New York now and Andy's still in L.A.

That's awesome. Shout out to those dudes. That's right. So we're back. We're back. all of a sudden headed toward watches, everyone. And I mean, this, again, could be an entire episode on watches, so we're not going to get to in the weeds.

But those spring-based clocks, of course, that spring was kind of the key in the 15th century, eventually involved to wearable clocks like Flav of Flav, and then eventually we got to watches by the 16th century. Of course, we were talking about pocket watches initially, kind of thing you hang from your vest or your belt or something, and it was a real fashion. statement at the time. But as that technology progressed, they got smaller and smaller, maybe not more accurate, but just smaller enough to where you could finally put one on your wrist if you were the Countess of Hungary in 1868. Yeah. Or one of Emperor Wilhelm I,

the second's German naval officers in 1880. Right. Because before that watches were women's jewelry. That's what they were considered. Wilhelm the second said nine. Now it's going to be military gear. Yeah. And from World War I, which came a little later, the American and other allied troops who came back home were like, you should see these hand clocks these guys have. And those became very quickly, starting around the 20s, fashionable in the United

States and I think Great Britain. And in the 20s, because they became fashion, all of a sudden, there was a lot of attention on hand clocks, and they became a lot of innovation. just kind of started to build very quickly starting in the 20s. Yeah, and, you know, a lot of this stuff that you, a lot of features that you have on a watch, if you're a watch person, comes from military usage. Like the, of course, I can't remember any of this

because it's off the dome and I'm a forgetful person. But, you know, the watches that have the little buttons on each side of the winder, and you can, like, click it to start something and then click it to stop it. Yeah, stop watch? No, stop. Just like on a regular wristwatch, there's a name for it.

I mean, I have one of them. I just can't think of it right now. But it's for a stopwatch function, though, right? Well, yeah, essentially. But as it pertains to the regular time. But that was essentially, I think initially, to keep track of like when you would launch a, not a missile, like the kind of bomb you drop in a tube

and it shoots somewhere. A torpedo? Sure. No, like, you know when you drop it in a tube and it shoots up in the air, those things? Yeah, drop a shell into a tube and then like when it would make the explosion, you would keep track of like you would time that out so you would know like how far it's going and calculate that. Oh, smart. I think that's the deal. I hope I'm not wrong. Someone will correct me.

Well, what about water resistance? Yeah. I mean, if you if you want to dive or just frolic, then you're going to need a waterproof watch. And that came along with the Rolex, the oyster specifically in 1926. And then in the 1950s, that's when stopwatch functions, although that was around during the war. So I'm not sure the difference between what I was talking about in an actual stopwatch. And my favorite feature, which is luminescence. As you know, I kind of became a bit of a watch guy.

And I don't have a ton of them, but got like seven watches. And one of them is a, oh, not for real watch people. Okay. They have like dozens and hundreds. But I have one called a loom tech. And that is the most luminescent that you can get, I think. And that thing is so bright and cool, I just love it. Does it leave, like, floaters on your vision after you look at it?

No, but if it's, like, fully charge and go into a dark closet or something, it's like, it's super bright green and it's awesome. I love it. So you can really time out your spin the bottle. Oh, you know it. Because I don't want to be in that closet for any longer than I have to be. I was raised Baptist. Making awkward conversation?

Yeah, totally. So if you are like, I want to hear more about watches. T.S. We're pretty much at the end of the episode. But I would recommend going and listening to our swatch episode because we talked a lot about the transition from mechanical watches to digital watches in that episode, if I remember correctly. It was pretty interesting.

Yeah, for sure. Chronographs, that's what I'm talking about with the watches, by the way. But what does it do? It's like a sub-dial for the seconds and minutes and hours, I think. So the top button will be a start-stop and the bottom is a reset. So it would function as like a stopwatch. But I think they got their start with timing out shells when they exploded, if I'm not mistaken. But not torpedoes.

Yeah, I think. But again, off the dome, so if I'm wrong, all apologies. You saying chronograph reminded me of one little tidbit I forgot to mention. Remember how we talked about planetary hours, and the Romans were like, this is when you worship, you know, Mars or whatever? Yeah. That is where the word horoscope came from. Horoscope means hour marker. Oh.

Pretty neat, huh? Yeah, I like that. Okay. Nifty. I like it, too. And since Chuck said he likes it, that obviously means it's time for listener mail. That's right. And we read this from Bill, I guess he would pronounce this, Rucheline.

because he asked a question about the appropriateness of our live show. And we've gotten a few emails, so we thought we'd kind of get the word out. Hey, guys, been listening for 10 years since commuting from Erie to Pittsburgh for a new job. You fill countless hours of boredom with education and smiles as my family, and I now listen to your show almost weekly, and my now almost 11-year-old son has grown up listening to you guys since shortly after he was born. Nice. So, we're coming to your show in Akron, Ohio, and we're pretty.

pretty ecstatic about that. We can't wait to come, but I was hoping you respond and let me know if the content is appropriate for our 11-year-old to come. We're loose with what he's allowed to listen to and don't try and shield him too much from the world. Everything you put out is educational. For instance, the Operation Mincemeat episode is one of our favorites. But if there's anything particularly mature like murder stuff or like the Lizzie Borden episode, we should probably be responsible parents and Bill and others. We're here to say that we're not going to reveal the topic,

but this one is very much kid appropriate. The only thing you might hear, we like to delight people with a few odd curse words here and there because we don't do it on the show. But it's still, what do you call it, PG, PG-13. PG-11, maybe? Yeah, okay. These days?

Yeah, I would even say depending on the kid, maybe PG-8, we get some fairly young kids at our shows, and I've never seen a parent leave with the child. They usually just leave them behind. I think in Scotland, didn't that when family leave? Yeah, I still don't understand that. We didn't say anything even remotely offensive. Yeah, agreed.

And I think they just didn't like the sounds of our voices or something like that. I don't understand it, but I don't think it was anything we said. Okay, good. Well, content-wise, though, this one is super on the up-and-up and kid appropriate. Nothing scary at all. Super pop-cultory, historical, kind of interesting. but just maybe a curse word or two. Yeah, maybe a blue joke here or there, but hopefully over any kid's head.

Yeah, that's what we like to do, is confused children so their parents can explain on the way home. That's exactly right. That's great, Chuck. That was a good idea. If you're like, wait, you guys are going on tour? We absolutely are. I would direct you to Stuff You Should Know.com and click on the on tour button, and it will show you all the places we're going to be.

And if you click on those, it will take you to go buy tickets. So you can come see us. This is the first time in years and years, I guess, since we've been on the road. So we're kind of excited about coming back. We may be a little rusty. But that also usually means that those first couple shows get some high-flying hijinks. Yeah, get ready, Denver, the Mile High City, how appropriate. That's right.

And if you want to get in touch with us, like Bill, right? Bill did. Thanks for that email, Bill, and we'll see you in Akron. You can email us at Stuff Podcast at iHeartRadio.com. Stuff you should know is a production of IHeartRadio. For more podcasts, My Heart Radio, visit the Iheart Radio app. Apple Podcasts are wherever you listen to your favorite shows. What if mind control is real?

If you could control the behavior of anybody around you, what kind of life would you have? Can you hypnotically persuade someone to buy a car? When you look at your car, you're going to become overwhelmed with such good feelings. Can you hypnotize someone into sleeping with you? I gave her some suggestions to be sexually aroused. Can you get someone to join your cult? NLP was used on me to access my subconscious. Mind Games, a new podcast exploring NLP, aka neurolinguistic programming.

Is it a self-help miracle, a shady hypnosis scam, or both? Listen to Mind Games on the Iheart radio app, Apple Podcasts, or wherever you get your podcasts. Hey, it's Joel and Matt from How to money if your New Year's resolution is to finally get your finances in shape. We've got your back. Prices, they're still high and the economy is all over the place. But 2026 is the year for you to get intentional and make real progress. That's right. Yeah, each week we break down what's happening with your money, the most important issues to focus on and the small moves that make a big difference. Kick off the year with confidence. Listen to how to money on the IHeart Radio app, Apple

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