the Ptolemaic Clock

May 31, 2022 4:34 PM

In the regular clock the face bezels stay in place and the hands move. Why am I telling you this? Well, maybe you see where I'm going.

I went digging for this because the game-clock in V Rising looks like this, with the bezel rotating and the current time represented by what is under that small circle in the middle top. Someone made a similar thing that you can make with a 3D printer, or you could just buy one (tho reviews I've found have been disappointing).

posted by curious nu (55 comments total)

Someone who praises a clock design for being harder to read has failed to grasp the purpose of a clock.
posted by NoxAeternum at 4:37 PM on May 31, 2022 [12 favorites]

I think the main link is kind of a joke. :)

I do really like thinking about what the design of a clock says about a particular philosophy of time, which is why I went looking for more information. The other examples fix the hour "hand" at the top, but the main link says, "Okay, well, but you don't HAVE to!" and that's interesting too. And are those other options harder to read due to physiological things, or is it purely cultural?
posted by curious nu at 4:47 PM on May 31, 2022 [2 favorites]

This made me wonder, Why are clocks shape they are?" So thanks for prompting me to look at their history a little. Prevailing thought seems to be because sundials were round and moved clockwise as well so that was the natural form to copy for mechanical clocks for easy adoption. Side note: other forms of early timepieces, like water or incense clocks, didn't really have standardized forms in the way that sundials did.
posted by forbiddencabinet at 5:25 PM on May 31, 2022

I disagree that hard mode is "no numbers". I think hard mode is with numbers, but having the hour hand at the bottom, so you're constantly confusing 6 and 9.

I would like a clock with no numbers that indicates time by slowly gliding across the sky.
posted by phooky at 6:03 PM on May 31, 2022 [9 favorites]

"return to geocentric values!" was the line that got me laughing out loud.
posted by Saxon Kane at 6:07 PM on May 31, 2022 [4 favorites]

this is horrible and I love it
posted by DoctorFedora at 6:09 PM on May 31, 2022

If you have enough money you may be able to acquire a wadokei watch made by Masahiro Kikuno, whose hour signs move around depending on the season, using an older Japanese way of timekeeping where the daylight/nighttime are divided into equal segments regardless of how long that daylight is.

The mechanism, as you might expect, is bonkers.
posted by aramaic at 6:15 PM on May 31, 2022 [24 favorites]

Tangential I think, but the clock in the Duomo in Florence is a 24 hour clock, has but one hand, noon is at the bottom, and runs counterclockwise.
posted by sjswitzer at 6:39 PM on May 31, 2022 [7 favorites]

Someone who praises a clock design for being harder to read has failed to grasp the purpose of a clock.

I'm think he is being a little tongue-in-cheek about the benefits. For some context for those not familiar, the individual behind this is one Martin Krzywinski of BC Cancer, who is a genomics data visualization legend behind the original Circos.
posted by They sucked his brains out! at 6:41 PM on May 31, 2022 [1 favorite]

Between this quote:

It should now be clear that the Ptolemaic clock is superior to the standard clock. The reasons are

- it's much harder to tell time on the Ptolemaic clock, which makes your brain do more work
- it tips its hat off to a simpler time when we didn't know anything and hints at the possibility of regression anytime

and the hilarious newsroom bit, it's a pretty good joke.
posted by nushustu at 6:44 PM on May 31, 2022

I'm trying to remember the book where a time traveler tries to invent the clock a hundred years early, but can't figure out the proper gearing, so they end up with
- a one-handed clock with a little Sun on the end, in a 24 hour cycle
- our '3' position is dawn, '9' is sunset, and 12 and 6 are apogee/perigee; above the 'horizon' (3 to 9) is white, below is black.
So just a mechanical gauge for how far along in the day/night it is. 'three hours before sunset', etc.
But what about longer days in Summer, etc? You just move the 'horizon' markers to '4' and '8' or thereabouts, depending on your local latitude; to 2 and 9 in the winter
Another 'minutes' hand was added later. but by that point everyone had become accustomed to this setup, so that the :00 position was 3 (dawn of the hour) not 12.
posted by bartleby at 6:45 PM on May 31, 2022 [1 favorite]

Do you want to see some horrible watch faces?

TTMM faces for Pebble smartwatches

Story is that all these were inspired by TokyoFlash which are all analog

My favorite
ttmmhorizon, another fun one

Unfortunately these all disappeared when Pebble went under and the developer switched to Fitbit Versa. Also, everyone has an Apple Watch now and those have boring, legible watch faces only allowed by Apple.
posted by meowzilla at 6:51 PM on May 31, 2022 [5 favorites]

One thing I've always wondered is if clocks had been invented in the southern hemisphere, would clockwise be the opposite?
posted by BrotherCaine at 6:52 PM on May 31, 2022 [1 favorite]

Someone who praises a clock design for being harder to read has failed to grasp the purpose of a clock.

So you're saying Ptolemy ptime is pterrible?
posted by Greg_Ace at 6:53 PM on May 31, 2022 [6 favorites]

an older Japanese way of timekeeping where the daylight/nighttime are divided into equal segments regardless of how long that daylight is.

I had one of the most transformative museum experiences from wandering aimlessly around Ueno in Tokyo, where I chanced on a dusty little room that appeared untouched since the 1980s housing the Daimyo Clock Museum. Through a photocopy of a mimeographed English guide, I puzzled out that the strange contraptions there were incredibly complicated machines from the late 1800s that kept track of time in a way completely alien to how I'd ever conceived that time could be kept.
posted by Theiform at 6:54 PM on May 31, 2022 [9 favorites]

"Someone who praises a clock design for being harder to read has failed to grasp the purpose of a clock."

But the purpose of a watch is to look good on my wrist. So.....

Anyways, I find the minutes bezel to be superfluous. It's not hard to see that it's 4:15 because the marker is about 1/4 of the way between the 4 and the 5. (And if you need to be much more precise than that, then this isn't the timepiece for you.)
posted by oddman at 7:14 PM on May 31, 2022

If you don't care about easily reading the time and you want something that its designers think is pretty "celebrate[s] the spectacle of a benevolent nature constantly renewed" for looking good* on a wrist, have I got a watch for you.

*personal definitions of "good" may vary wildly
posted by sardonyx at 7:41 PM on May 31, 2022 [6 favorites]

So you're saying Ptolemy ptime is pterrible?

It's always four-ptwenty somewhere.
posted by rhizome at 7:51 PM on May 31, 2022 [2 favorites]

Seems to me the hands are completely irrevelant since they aren't moving, so you can just discard them and consider "straight up" as the current time. Then, you can layer the face with an opaque mask that has a transparent window at the "straight up" position to let you see just the current values on the moving hour and minute bezels. At say, quarter past ten, it would look like this:

[ 10 ]
[ 15 ] 

Or better yet, you could let the "9:00" position on the dial represent the current time, and rotate the masking plate so that the transparent window is over that area instead (you would need to print the numerals on the bezels rotated by 45 degrees so they would look right side up in the window). To be really fancy, you could overlay a colon right in the middle of the viewing window. With this setup, quarter past ten would look like this:

[ 10 : 15 ]

Hey, wait a minute...
posted by TwoToneRow at 8:03 PM on May 31, 2022 [11 favorites]

I would like a clock with no numbers that indicates time by slowly gliding across the sky.

Hi, I'd like to talk to you about one of our lords and saviors, He who glides slowly and inexorably across the sky at a predictable rate: RA-HORAKTHY, Ra Who is Horus of the Horizons, or, as you may know Him, THE SUN.
posted by PresidentOfDinosaurs at 8:14 PM on May 31, 2022 [5 favorites]

That is the worst way of telling time I've ever seen. I love it!
posted by dg at 8:16 PM on May 31, 2022 [1 favorite]

The best thing about these clocks is that for Daylight Savings you can just adjust the angle of the hour hand.
posted by Fiasco da Gama at 8:38 PM on May 31, 2022

I’ve got a Vostok watch with a 24 hour dial (divided into 24 instead of 12 for the hours). It is weird and hard to read but also kind of fun. Clocks and watches are art now. Everyone has a super accurate clock in their phone now if they must know the precise time quickly.
posted by interogative mood at 9:02 PM on May 31, 2022 [2 favorites]

So you're saying Ptolemy ptime is pterrible?
It's always four-ptwenty somewhere.

Blaze ipt.
posted by Greg_Ace at 9:28 PM on May 31, 2022 [3 favorites]

the Duomo in Florence is a 24 hour clock, has but one hand, noon is at the bottom, and runs counterclockwise.

Whichever way a clock runs is clockwise, by definition. That clock's wise is widdershins.
posted by agentofselection at 9:30 PM on May 31, 2022 [5 favorites]

Bruce Buffer, says, "it's time!!!"
posted by shoesfullofdust at 10:12 PM on May 31, 2022

I've posted that wadokei watch more than a couple of times, here's my version:

$ sunclock.pl 
子   丑   寅   卯   辰   巳   午   未   申   酉   戌   ▃▃   亥   子
0050 0228 0405 0543 0805 1028 1251 1513 1736 1959 2136 2204 2313 0051

(the terminal gets the spacing right)
posted by zengargoyle at 10:13 PM on May 31, 2022 [1 favorite]

Whichever way a clock runs is clockwise

But how wise is a clock, really?
posted by Greg_Ace at 10:32 PM on May 31, 2022

Does anybody know what time it is
Does anybody really care
posted by Greg_Ace at 10:36 PM on May 31, 2022 [2 favorites]

Summertime?
posted by dg at 10:43 PM on May 31, 2022

I should note that there is an actual Ptolemaic clock, of sorts, on the Annapolis and Santa Fe campuses of St. John's College, where we actually read the Almagest as part of the curriculum. Part of learning about how Ptolemy thought about astronomy involved taking measurements of the sun's position relative to the earth with the stone, which also indicates whether or not there is an equinox.

Contrary to the idea a lot of folks have about Ptolemy, there's no ignorance here; in fact he was building on a huge body of knowledge going back to the Babylonians. It's just that, as Thomas Kuhn would say, the framework with which he understood celestial mechanics prevented him from seeing what was really going on. Which is pretty relatable, if you ask me.
posted by Cash4Lead at 11:10 PM on May 31, 2022 [7 favorites]

It nicely avoids both the easy-to-read hand positions of an analog clock and the large, easy-to-read numbers of a digital clock.
posted by straight at 11:17 PM on May 31, 2022

The best system of timekeeping is microwave time, where 99 is longer than 100.
posted by oulipian at 12:26 AM on June 1, 2022 [4 favorites]

Why no epicycles?
Add another bezel with a 60:1 gear to the outer rim and you've got minutes. A third would indicate seconds.
posted by bartleby at 12:39 AM on June 1, 2022 [2 favorites]

Yeah, as a fellow johnnie with a strong interest in the history and philosophy of science, the whole ptolemy-as-a-punching-bag thing is a pet peeve of mine because it's an example of faux-sophistication; or maybe it's better described as a common flex of middlebrow cultural capital that isn't as impressive as people think. But I'm maybe starting to get overly salty. Sorry.

Anyway, one I thing I always mention about Ptolemy is that in the Almagest he explicitly addresses the point that a heliocentric model is much simpler. This undermines the conventional wisdom that he was some sort of an idiot for not even bothering to consider heliocentricism before layering epicycles on epicycles in his complicated geocentric model. Rather, his answer to that criticism is that, yes, the heliocentric model is much more geometrically straightforward, but that no one is comfortable with the idea of the Earth in motion and, anyway, the calculation of the distance to the fixed stars given the lack of any visible parallax (under a heliocentric model of the Earth revolving around the Sun) produces a truly absurd result of the minimal distance to the stars^†. In other words, yeah, this alternative description is much more mathematically attractive but it unfortunately violates a number of basic assumptions that are widely held to be self-evidently true.

And this is just how advancement in knowledge works, generally, and science in modern times, specifically. Today's "everyone agrees these assumptions are self-evidently true" are tomorrow's "this is going to blow your mind, but..." paradigm changes.

There is an intense and misleading "presentism" in science education — we're taught in such a way that there's a strong implication that now we mostly have things right, unlike those ignorant people who came before. And they were ignorant, in a manner of speaking. But so are we.

If you're very scientifically literate and have been from early childhood, as I have, it's extremely interesting to live into one's late middle-age and beyond because you've seen so many examples of scientific conventional wisdom overturned during your lifetime. To be sure, I have little tolerance for "the limit of the speed of light is just, like, your opinion, man" lazy pop-skepticism kind of stuff you often see. My point is more oriented toward the idea that empirical science is always provisional and a work-in-progress, and that past natural philosophers and scientists weren't idiots and scientific advancement requires a kind of humility.

Most of the working scientists I've known necessarily acquired an intuition about this just from their daily practice of science, even if they didn't have any educational grounding in science history or philosophy. It's really the general public who ends up with a very misleading view of science because of this presentism — changes in the consensus often undermines public trust in science when, actually, that's just demonstrating that institutional science is working as designed.

† In this respect, Ptolemy reveals a greater cosmological understanding than most laypeople today. While most people internalized some basic cosmology from school, that almost always is undermined by the lack of a comparable numeracy with regard to things like magnitudes of distance and time. For example, I'd wager most people would greatly underestimate the communication delay to the Voyager spacecraft while also greatly overestimating how far from the Sun they've traveled (given their age) relative to, say, the stars closest to us. At the same time, I've lately seen twice in unrelated media the claim that the light from all the stars in the sky we see is billions of years old, which isn't true, but also it's common in science-fiction film/tv to either ignore the existence of other galaxies or elide their vast distance from our own. The point is that Ptolemy objects to heliocentricism because it implies that the stars we see in the sky are unimaginably distant, and he's correct because people today clearly have no idea of just how far that really is.
posted by Ivan Fyodorovich at 12:45 AM on June 1, 2022 [16 favorites]

Ivan Fyodorovich: I think you would enjoy the Isaac Asimov essay The Relativity of Wrong.
posted by foxfirefey at 12:57 AM on June 1, 2022 [1 favorite]

This silly Ptolemaic Clock has nothing on my analog Epoch Time watch.

Posted @ 1654078690
posted by loquacious at 3:18 AM on June 1, 2022

Also, everyone has an Apple Watch now and those have boring, legible watch faces only allowed by Apple.

Actually, if you're into astronomy the Apple Watch Solar face is pretty damn cool. Or so my friend who has an Apple Watch consonantly reminds me. Sadly not available as a regular iOS app (*). There is however Solar Time which provides local corrections based on GPS.

(*) - If someone knows of an equivalent app for iOS, please let me know. I've not been able to find one.
posted by Insert Clever Name Here at 4:02 AM on June 1, 2022

I kinda skimmed this looking to get mad at some damn fool trying to make his mark by telling us how “We’ve been doing it all wrong!,” and then I stopped skimming and properly read the end and had a good chuckle—at myself and the world. Good stuff.

Go ahead and put this non sequitur on my tombstone: “it tips its hat off to a simpler time when we didn't know anything and hints at the possibility of regression anytime.”

Anyway, it’s snowing here this morning.
posted by Don.Kinsayder at 5:31 AM on June 1, 2022

I just want a shorter workday and the permanent end of DST, regardless of how we measure time.
posted by bile and syntax at 6:52 AM on June 1, 2022 [2 favorites]

A long time ago, I got a Stonehenge pocket watch, which has both a traditional watch-face and a compass and sundial, complete with micro-megaliths.
posted by cheshyre at 7:05 AM on June 1, 2022 [1 favorite]

I was gifted a clock rather like this. It's three layers of wheels that turn for hours, minutes, and seconds. Except that instead of numbers, each one has a trangular path drawn around the edge that varies continuously from a point to a wide region, each in a different color.

It's more of an art piece than a real clock. But, for questions like, "roughly what time is it," where being off by an hour won't hurt, it's pretty easy to read. And it's great for keeping an eye on one minute or 15 minutes.
posted by eotvos at 8:04 AM on June 1, 2022

This reminds me of a clock I bought at a Goodwill once. The face was mirror flipped on a vertical line, and the mechanism ran in reverse.
posted by shenkerism at 8:31 AM on June 1, 2022

I’d kind of love a mixed clock where the hour was told by a rotating ring (current time @ 12 o’clock) but the minutes were a traditional hand. Does this exist??
posted by wemayfreeze at 9:52 AM on June 1, 2022

This reminds me a bit of the Ressence watch, though conceptually it's quite different.
posted by mbrubeck at 9:58 AM on June 1, 2022

I still have my ancient ThinkGeek binary watch. The battery is dead. But the memory of trying to figure out the time when baked lives on.
posted by Splunge at 10:57 AM on June 1, 2022 [1 favorite]

But how wise is a clock, really?
It’s hard to say. Only time will tell.
posted by evidenceofabsence at 11:35 AM on June 1, 2022 [3 favorites]

And I think I should have explained my joke/concept for a Unix Epoch Time watch better.

The clock has one hand. It starts at the 12 o'clock position representing January 1st, 1970, and for the 32 bit version it returns to the 12 o'clock position at 03:14:07 UTC on January 19th, 2038 and then the watch halts and catches fire after the single hand rotates exactly once.

For the 64 bit version it operates and looks exactly the same except the single clock hand doesn't return to the 12 o'clock position until 15:30:08 UTC on December 4th in the year of Our Lord 292277026596.

The watch may come in a plain, unnumbered version with a blank face, but for a small additional fee a numbered dialed version will be available using finely microetched quartz or silicon monocrystalline face plates and comes packaged with either a complimentary scanning electron microscope for the 32 bit unsigned version or an atomic force microscope for the 64 bit version in their own handsome packing cases and support furniture, along with a handy user manual that helpfully details that any quantum uncertainty in reading precise time values are definitely the end user's problem and that maybe they should generally observe the position and/or velocity of things much less.
posted by loquacious at 3:52 PM on June 1, 2022 [8 favorites]

For me the most important thing about a timepiece, besides reasonable accuracy and reliability, is the ease of reading the time it displays. In a single word: clarity.

I want to be able to glance at my wrist and know what time it is without having to study and decode the dial config. The less time it takes for me to read the time, the better. Visually cluttered dials I like not. I want minimal complications and design elements, and good contrasts.

There is a reason the standard 2 or 3 hand rotary dial design in clocks and watches is still with us and popular, and it's not just because of familiarity or history or cultural dominance. It is at least as much, and I would argue more, because it is intuitive and easy to use.
posted by Pouteria at 10:47 PM on June 1, 2022 [1 favorite]

meowzilla: Unfortunately these all disappeared when Pebble went under and the developer switched to Fitbit Versa.

For shame! I would have loved to try some of these on my Pebbles. If only they would have left them in place, to be available through Rebble.
Fitbit has a lot to answer for.
posted by Too-Ticky at 12:10 AM on June 2, 2022

Pouteria: is the ease of reading the time it displays... There is a reason the standard 2 or 3 hand rotary dial design in clocks and watches is still with us and popular, and it's not just because of familiarity or history or cultural dominance.

I'd say that familiarity is a bigger part of it than you might recognize, given that on the typical two-hand design you have to either multiply by 5 or memorize in order to figure what minute it is.
posted by clawsoon at 8:40 AM on June 2, 2022

Some clocks and watches have a numbered minute ring. On watches it's often a rotating ring around the outside of the face.
posted by rhizome at 4:51 PM on June 2, 2022

A clock with hands is a statement that it doesn't matter whether it's 10:33 or 10:34; about half-past ten is all you need to know.
posted by straight at 9:14 PM on June 2, 2022

I long for the days when approximate times were good enough. "Within 1/3 of an hour" is more persnickety than I ever wanted to be constrained to. which is weird, considering that I'm more often early than late for things
posted by Greg_Ace at 10:16 PM on June 2, 2022

vaguely related, vaguely cursed content
posted by cortex at 5:46 PM on June 3, 2022