Loading summary
Chuck
This is an iHeart podcast. Guaranteed Human. Welcome to Stuff youf Should Know, a production of iHeartradio.
Josh
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.
Chuck
Yeah, Olivia helped us put this one together. I think the charge was, hey, how about something on the history of timekeeping without getting too 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.
Josh
Oh, nice. Nice astronomical cosmological reference there.
Chuck
Well, I think that is a reference for a lot of things, right?
Josh
Nope, just that.
Chuck
Okay.
Josh
Where'D you get this idea? Cause this was when you came up.
Chuck
With, you know, man, I don't know. I think I was maybe thinking about a watch on my wrist and then wondering about. 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, like, 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.
Josh
Yeah, but earlier than you'd think. Or earlier than I thought, at least.
Chuck
Yeah, agreed.
Josh
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 gnomon. 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.
Chuck
Oh, really?
Josh
Yeah. And that just.
Chuck
Like, hey, check out the gnomon on that guy.
Josh
Yeah, almost exactly that. If not that, but just said in ancient Greek.
Chuck
Okay, gotcha.
Josh
In Hellenic. But just tracking the shadow that the gnomon cast. Hopefully just a stick in the ground. That was early timekeeping.
Chuck
Oh, man, I have a thousand jokes. I'm just gonna walk right past at this point.
Josh
Good for you, buddy. You're a pro.
Chuck
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. So 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 archeological site that they found, dated back to 2300 BC. And again, as you'll see, this is a recurring theme. Like I mentioned, it wasn't necessarily like, hey, we gotta 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.
Josh
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 gnome on. And the other person's like, no, no, pull that out. And they're like, no, I mean, the stick.
Chuck
Right.
Josh
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 noman. 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 look at its feet. That's essentially.
Chuck
That's kind of perfect, actually.
Josh
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 tail casts on the rest of the tea 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 as the sun is setting in the west. Pretty spectacular, considering that's close to 3,000 years old.
Chuck
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.
Josh
Yeah. Sadly, buck naked. I have to admit that I had to go lay down and figure it out myself.
Chuck
Okay, that's good.
Josh
But, yes, I was needed to. Nice work.
Chuck
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 named Anaxmander. Very cool name. Not Alexander, but Anaxmander of miletus. This was 6th century B.C. 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 eventually, much later, we'll get to minutes. But the hourly timekeeping started in 350 BCE.
Josh
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 them like that, like they'd make the one, split it in two, and then all of a sudden, they had two hemicycles to sell.
Chuck
I bet you're getting really good at describing things at this juncture in your career.
Josh
It took me long enough. We're almost to year 18. It's dismaying to try to explain something and then 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.
Chuck
By the way, quick correction, because a listener just wrote in about this. We're about to be at year 19 completed. Year 18. Technically, no.
Josh
Really?
Chuck
Yeah. Because year 19 and year 20 are, you know, the two next years. Does that make sense?
Josh
It does, but I feel like it's wrong because started in April 2008 and going to April of 2026, that's 18 years completed. I see. Yeah. I should have known, right? When somebody busted out math, I should have just been like, yep, that's right.
Chuck
The cool thing about the Hemi cycle, besides the fact that people back then probably said, is that thing a hemi? When they walked by, you know, I 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 gonna 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.
Josh
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.
Chuck
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 is 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 is something that could be done in a shorter amount of time. Like, that'll just take you a winter hour.
Josh
Yeah. And this was. So this is 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.
Chuck
Yeah, except we're just. You know, modern humans are way too anal to just let it kind of flow like that. Still gotta be exact, you know.
Josh
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 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.
Chuck
Yeah. So, like, once they could do that, they would hang it facing the Sun. So that. That little pointers, I guess. Was it still called a gnomon at this point?
Josh
I would think so. I think some people still call them gnomons when they're referring to sundials.
Chuck
Yeah, I think you're right. But they would face the sun so that that pointer 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.
Josh
Yeah, it was like the staff of Ra model.
Chuck
Oh, yeah.
Josh
So there were. There was a big reason that people were keeping track of the hours 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. This little line, essentially.
Chuck
Right, yeah, yeah.
Josh
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.
Chuck
Yeah.
Josh
Each of those hours was associated with the different astrological sign. It was called planetary hours. And it was because. So you could maximize whoever you are worshiping. So, like, if you were worshiping Selene, 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.
Chuck
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 in 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.
Josh
Cute.
Chuck
That kind of sundial is what the Muslims came up with. The one that's got the flat circular base and that gnomon is. Am I saying that right? Yeah. The gnomon is parallel to the polar axis of the planet.
Josh
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.
Chuck
And then finally, I think before we break, we should give a shout out to early 13th century Moroccan mathematician Abu Alhazan Al Maraqshi. 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.
Josh
Very nice.
Chuck
Yeah.
Josh
All right, well, let's take that break then. It's time.
Chuck
All right, we'll be right back.
Josh
Learn some stuff with Joshua and characters.
Chuck
Hey, everybody. The new year is here. So you need to get back into an at home routine that you love and elevate your space with Wayfair.
Josh
That's right. It's a new year. It's a new you. And you can update your place with all sorts of great things on Wayfair like bath and bedding. You can refresh your kids room to help get them on track for this new year. And there's storage. Everyone needs storage right now. And Wayfair has storage for every space for your outdoor furniture, your bathroom. You want to organize your life, go to Wayfair.
Chuck
That's right. What about some kitchen essentials for easy weeknight dinners or, I don't know, do you work at home? You need a good study set up for college or high school. They got desks, they got office chairs, and they got bookcases, of course.
Josh
So get organized, refreshed, and back on track this new year. For way less, head to Wayfair.com right now to shop all things home. That's W-A-Y-F-A-I-R dot com. Wayfair. Every style, every home. Okay, Chuck, so we're back. And before we move on, I want to say that I finally got it. Reggie Watts original.
Chuck
Did you listen to it?
Josh
Yeah, when I was qa' ing it, I got it and I was like, man, that zoomed right past me.
Chuck
Well, you were in a thought, and I slipped it in there very stealthily.
Josh
It was very great.
Chuck
All right, Nice little treat.
Josh
We're talking about the national radio Quiet Zone episode by the Way, everybody.
Chuck
That's right.
Josh
So you got sundials. Next thing that we moved on to is water. A bunch of different cultures came up with water clocks. It's not clear if, again, it started in China and, and move to Greece and then move to the Muslim countries, who knows? But it's also possible that this, 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.
Chuck
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?
Josh
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 weren't 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.
Chuck
Yeah. I wonder if there was ever like, I'm sorry I'm late. You know, we had a cold snap. My water clock froze. Yeah, like, you got to move those things inside, buddy.
Josh
I guarantee somebody used that excuse.
Chuck
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 solved a lot of the problems because mercury wouldn't freeze. It wouldn't have different viscosities at different temperatures, and it would ensure that you're on time to that appointment.
Josh
Yeah. And that engineer was Zhang CI Jun.
Chuck
He show off. I was just going to walk right past that.
Josh
Here's my favorite kind of early type of thing.
Chuck
Ooh, me too.
Josh
Is it? Yeah. I'm not surprised. Incense clocks.
Chuck
Yeah. And I'm not even into incense anymore. I was in college. I think, like, most people are.
Josh
Same here. I used to burn some frankincense, man.
Chuck
Yeah, me too. But I really love this one. This Existed in China at least since the 6th century CE, also in other parts of Asia and Korea and Japan for sure. But I love the idea. Cause essentially 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?
Josh
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'd put on top of the box to create different times. So, like, if you wanted an hour, that 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.
Chuck
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, like, ingenious in its simplicity. And also like, you know, you know what happens at Sandalwood time. The sexiest time.
Josh
Yeah, I've got jokes that I'm keeping to myself.
Chuck
Yeah, good.
Josh
There are 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.
Chuck
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.
Josh
That's right.
Chuck
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.
Josh
Yeah. You could also take, say, a four hour candle and break it, like just mark equal lines, cross 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 6th 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 the 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.
Chuck
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.
Josh
That's nuts.
Chuck
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.
Josh
Yeah. When it's humid out, the soap opera Days of Our Lives never get started.
Chuck
Right.
Josh
It's sad.
Chuck
Was that the one you watched in college?
Josh
I think that's what people wrote in and said. Yeah. I'm pretty sure I couldn't remember.
Chuck
Okay.
Josh
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 45ft tall. It's still standing. But when it was in use, it had water clocks, it had sundials. You could, you could gauge the wind, you could tell what was going on celestially. He just basically packed every neato timekeeping invention that was around at the time into this thing.
Chuck
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. 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.
Josh
It went every 15 minutes.
Chuck
That's right.
Josh
There's a guy named Su Sung who is very famous for his 35. 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. Yeah, like 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 Jazari. 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 in 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 cymbals and stuff. It's just amazing, especially when you learn about how every single step works.
Chuck
Yeah, that thing, you sent that to me. That was super cool looking. Yeah, very ornate. Now we kind of get to the point. Shall we break or can we keep Going.
Josh
Yeah, let's take a break.
Chuck
All right, we'll be right back.
Josh
Learn some stuff with Joshua and Charles. Stuff you should know.
Chuck
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 and we're getting closer and closer to keeping track of seconds, although that'll be a second till 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 the Muslim world at the same time or if it kind of spread out from one place to another. Another origin story is maybe mechanical clocks came from Europe with. Would it be Gerbert?
Josh
I think so.
Chuck
Gerbert of Aurillac, who was a French scholar, but you might know him a little better as Pope Sylvester ii.
Josh
Oh, okay.
Chuck
Because he would become Pope later on. He, 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.
Josh
Right. Which makes some people suspect that he might not have actually done that.
Chuck
Yeah.
Josh
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, say, flowing downhill to run gears and stuff like that. Those are, those are the mechanical time devices that were, that were some of the original mechanical ones. 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. If you hold a, a weight up on a rope and let it fall down, gravity is 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.
Chuck
Yeah, for sure. There was a monk in 1271 named Robertus 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 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.
Josh
Yeah. And one of the inventions that really kind of. It was a game changer. It's called the virgin foliot mechanism. Essentially, you remember in Karate Kid 2 where all of those Okinawan villagers are sitting there playing their hand drums? Yeah.
Chuck
Yeah.
Josh
Okay. So that's essentially a virgin, 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 foliate. And the foliate turns, like, slowly one way and then slowly back another. And when it moves back in position and 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.
Chuck
Yeah. And, you know, it stays constant because that thing is constantly stopping and starting, so it's gonna keep that weight from picking up momentum as it. 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.
Josh
Yeah. And the. But you wouldn't. It doesn't move like a Okinawan hand drum moves. I mean, it moves not as fast, I should say. That'd be. It'd be out of control. Clock.
Chuck
Yeah. And didn't that drum move faster and faster the more intense that the scenes got in that movie? Yeah.
Josh
Oh, yeah, man. It really helped build the suspense, I think, during the main fight maybe.
Chuck
Yeah. I mean, it was a pretty smart device for a movie.
Josh
It was a good sequel as far as sequels go. They didn't just, you know, build on the last one. They really kind of went all out in recreating things.
Chuck
Yeah. And one of the great bad movies of all time. And I'm lobbying to get on 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.
Josh
That even worse than Jaden Smith's Karate Kid? Because I heard that was pretty bad.
Chuck
I didn't see it. But Karate Kid 3. Oh, man. If you're into a fun bad movie to watch with people, Karate Kid 3 is one. And that was one where I thought I talked about on the show at some point, but where. God, Ruby was probably, like, 6 years old and came up with, like, legit. Her first quality joke watching that movie.
Josh
Can you share it?
Chuck
I don't know if it would translate. I'll tell you later.
Josh
Okay, that's fine. But good for her. Six is a good age to come up with a quality joke by.
Chuck
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 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 San and Miyagi in a forest. And Ruby said, that'd be funny if they reached over to a tree and turned the moon off.
Josh
That's good. That is a quality joke.
Chuck
It's a pretty good joke.
Josh
Yep. Yeah, Yeah. I haven't seen The Karate Kid 3. I know of it. I know Hilary Swank's the Karate Kid in that one.
Chuck
No, no, no, no, no. Well, maybe I'm getting the number wrong. Karate Kid 3 was actually Daniel and Miyagi still.
Josh
Oh, was it?
Chuck
Yeah, unless I have it out of order, it's not. But I know it's not the Hilary Swank one, obviously.
Josh
Okay. All right.
Chuck
Yeah. So it's either three or four.
Josh
Well, I haven't seen the one you're talking about either. I don't remember anybody turning off any lights anywhere.
Chuck
Yeah, it's truly bad in a great way.
Josh
Okay, so just back to clocks. Just like in the Muslim world, timekeeping pieces in Europe were initially to keep people on track for daily prayers. Apparently, monks in monasteries prayed seven times a day, but there were also meals. There was also beer brewing time. And so these. These early clocks, the. Using the virgin foliate mechanism and weights, they help keep the monks on track. Yeah. 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.
Chuck
Yeah, for sure. Nice little Factoid there.
Josh
I love that one.
Chuck
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?
Josh
I guess, like that glass thing, Dome you put over stuff.
Chuck
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, not that hard. We can do that.
Josh
They're like, are you talking about a moving gnomon? And the monk said, that's exactly what I'm talking about.
Chuck
That's right.
Josh
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 the sky would turn purple at one in the afternoon in medieval Europe. And there's a philosopher named Lewis 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 BlackSmith shop at 3, or else you're fired. You know. What a drag. Exactly. I think that's a really good case that he makes.
Chuck
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.
Josh
Right. And thanks for letting me take that Lewis Mumford little tidbit.
Chuck
Oh, yeah. Did you like that one?
Josh
I love It. It's almost as good as the different smells of incense.
Chuck
Yeah, well, you know, we like to scratch each other's backs.
Josh
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 in clocks with coiled springs meant they became portable, because, of course, humans love to make things portable.
Chuck
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, Galilee 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 chord using his own pulse beat as a reference. Pretty cool.
Josh
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 a 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 Huygens, the son Galileo always wanted, he ended up creating that clock. The first pendulum clock that Galileo had kind of come up with.
Chuck
Yeah, that was in 1656. And almost right after that, there was an English scientist named Robert Hooke with an e at 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 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 degree swing to 4 to 6 degrees, which again, meant you could pack it in a packageable size.
Josh
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. 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's 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 had 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.
Chuck
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 was about. I mean, it's kind of a sad song about a clock that this guy had who or his grandfather had. And it 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.
Josh
You know, that's a redux of our first short stuff.
Chuck
I thought we had talked about that. Right.
Josh
That was the very first clock.
Chuck
The very first one, huh?
Josh
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. They produced reliable oscillations that you could track for time. And people figured out how to use that in watches. For that, I would say go listen to our atomic clock episode.
Chuck
Yeah, that was a good one out.
Josh
From crystal quartz came atomic clocks. And from atomic clocks came things like GPS is how your iPhone or, you know, Google phone keeps track of the time. The knows exactly what time it is, thanks to an atomic clock. So we went from sun to water, to pendulums, to crystals to atoms.
Chuck
That's right. And by the way, I bet I made that same dumb Henry Clay joke in that short stuff, didn't I?
Josh
I'll have to go back and listen, but anytime you get a chance to mention Henry Clay people, you do. And I support it fully.
Chuck
Of course, for those of you who don't know, Henry Clay People was a great band and friends of the show from our good pals Joey and Andy Ciara, the brothers, musical brothers, screenwriting brothers. And they did the theme song to the Stuff youf Should Know TV show.
Josh
That's right. It was a great theme song, very catchy.
Chuck
And they're still great friends. I see Joey all the time. Cause he lives in New York now and Andy's still in la.
Josh
That's awesome. Shout out to those dudes.
Chuck
That's right. So we're back. Not we're back, we're all of a sudden headed toward watches, everyone. And I mean this again could be an entire episode on watches. So we're not gonna get too 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 Flavor 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.
Josh
Yeah. Or one of Emperor Wilhelm II's German naval officers in 1880. Because before that watches were women's jewelry. That's what they were considered. Wilhelm II said, nein, now it's going to be a military gear.
Chuck
Yeah.
Josh
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 innovations. Just kind of started to build very quickly, starting in the 20s.
Chuck
Yeah. And you know, a lot of this stuff that, 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?
Josh
Yeah. Stopwatch.
Chuck
No, not a stopwatch. 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.
Josh
But it's for a stopwatch function though, right?
Chuck
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.
Josh
A torpedo.
Chuck
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.
Josh
Oh, smart.
Chuck
I think that's the deal. I hope I'm not wrong. Someone will correct me.
Josh
Well, what about water resistance?
Chuck
Yeah. I mean, 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 not for real watch people. They have like dozens and hundreds. But I have one called a Lume 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.
Josh
Does it leave, like, floaters on your vision after you look at it?
Chuck
No, but if it's like fully charged and go into a dark closet or something, it's super bright green and it's awesome. I love it.
Josh
So you can really time out your. Spin the bottle.
Chuck
Oh, shh. You know it. Because I don't want to be in that closet for any longer than a half. I was raised Baptist.
Josh
Making awkward conversation.
Chuck
Yeah, totally.
Josh
So if you are like, I want to hear more about watches, ts 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.
Chuck
Yeah, for sure. Chronographs. That's what I'm talking about with the watches, by the way.
Josh
But what does it do?
Chuck
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 and when they exploded, if I'm not mistaken.
Josh
But not torpedoes.
Chuck
Yeah, I think. But again, off the dome. So if I'm wrong, all apologies.
Josh
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?
Chuck
Yeah.
Josh
That is where the word horoscope came from. Horoscope means hour marker. Oh, pretty neat, huh?
Chuck
Yeah, I like that. Nifty.
Josh
I like it too. And since Chuck said he likes it, that obviously means it's time for listener mail.
Chuck
That's right. And we read this from Bill. I guess you would pronounce this rude 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.
Josh
Nice.
Chuck
So we're coming to your show in Akron, Ohio, and we're pretty ecstatic about that. We can't wait to come, but I was hoping you'll 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, you know, 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.
Josh
Yeah. Okay.
Chuck
These days.
Josh
Yeah, I would even say, depending on the kid, maybe PG8. 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.
Chuck
Think in Scotland, didn't that one family leave?
Josh
Yeah. I still don't understand that. We didn't say anything even remotely offensive.
Chuck
Yeah.
Josh
And I think they just didn't like the sounds of our voices or something like that. I don't understand it maybe, but I don't think it was anything we said.
Chuck
Okay, good. Well, content wise, though, this one is super on the up and up and kid appropriate. Nothing scary at all. Super pop culture y historical kind of interesting. But just maybe a curse word or two or three.
Josh
Yeah. Maybe a blue joke here or there, but hopefully over any kid's head.
Chuck
Yeah. That's what we like to do is confuse children so their parents can explain on the way home.
Josh
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 stuffyouchouldknow.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.
Chuck
Yeah.
Josh
That also usually means that those first couple shows get some high flying. High jinks.
Chuck
Yeah. Get ready. Denver, the mile high city. How appropriate.
Josh
That's right. And if you want to get in touch with us like Bill. Right.
Chuck
Yes, Bill did.
Josh
Thanks for that. Email Bill and we'll see you in Akron. You can email us@stuffpodcastheartradio.com.
Chuck
Stuffy Should Know is a production of iHeartRadio. For more podcasts My Heart Radio, visit the iHeartRadio app. Apple Podcasts are wherever you listen to your favorite shows. This is an iHeart podcast. Guaranteed Human.
Host: Josh and Chuck
Date: January 20, 2026
Podcast: iHeartPodcasts
In this engaging and lighthearted episode of "Stuff You Should Know," Josh and Chuck explore the fascinating history of timekeeping. From humanity’s earliest attempts at tracking the passage of time with sticks and shadows to the evolution of mechanical and electronic clocks, the hosts walk listeners through millennia of innovation, mishaps, and clever inventions—sprinkled with characteristic banter and laugh-out-loud moments.
The episode’s purpose is to demystify how humans have measured, divided, and coordinated time over the ages, without delving too deeply into the mechanisms of the devices themselves, focusing instead on cultural and historical contexts.
"You can actually use it to track time throughout the day. And that is almost certainly the earliest way that humans tracked time. And the stick they put in the ground is widely known as a gnomon...also saw that it was slang in Greek for penis." — Josh (02:05)
"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..." — Josh (08:59)
"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..." — Josh (16:03)
"You could smell the time. So you knew when a certain smell came up, what time it was. Which I think is super, like, ingenious in its simplicity." — Chuck (19:03)
"...there were mannequins that came out and rang gongs...this is from the 11th century. So it's pretty impressive..." — Josh (24:03)
"Lewis Mumford...says that that is the birth of the modern era, not steam power...removing people from the natural rhythms of the day and imposing time on them." — Josh (34:31)
"And that is almost certainly the earliest way that humans tracked time. And the stick they put in the ground is widely known as a gnomon... also saw that it was slang in Greek for penis." — Josh (02:05)
"Seasonal 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..." — Josh (08:59)
"...you could smell the time. So you knew when a certain smell came up, what time it was." — Chuck (19:03)
"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." — Josh (34:31)
"Coiled springs meant they became portable, because, of course, humans love to make things portable." — Josh (36:23)
"Lewis Mumford...says that...removing people from the rhythms, the natural rhythms of the day and imposing time on them...That is the birth of the modern era, not steam power..." — Josh (34:31)
"...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." — Chuck (40:17)
"From crystal quartz came atomic clocks. And from atomic clocks came things like GPS is how your iPhone or, you know, Google phone keeps track of the time..." — Josh (41:33)
True to "Stuff You Should Know" tradition, the episode combines a rich, collaborative conversational flow, capable research, and off-the-cuff humor. Josh and Chuck strike a balance between historical detail and everyday relatability, providing both depth and accessibility. Their witty asides, self-deprecating jokes, and occasional pop culture tangents make the history of timekeeping not just educational but thoroughly entertaining.
If you ever wanted to know how humans went from reading the sun to glancing at their lit-up wrist for the time, this episode delivers the essential story—with chronologically relevant laughs, social context, and plenty of sidebars worth quoting. Whether you’re a horology enthusiast or just "watch" curious, you’ll never look at your phone’s clock the same way again.