Keeping accurate time has been a problem for humanity for basically our entire existence. All civilizations have constructed varied objects and buildings, out of communal resources, to keep track of the time. We do this because keeping track of the time is useful in an incredible variety of ways, from cooking, to industrial processes, to appointments, etc., most of which we’re now accustomed to given the transparent ease with which we can check the time these days.
I’d like to break down that transparency a bit, to talk about how we actually got our modern clocks, and what it says about our nigh-instinctual priorities as a species. This post is running against some word limit issues (this part is a mere ~2500 words), hence the two parts, but I do want to talk a little bit about timekeeping, time signals in our modern era, and then use that as a broader analogy for the costs and benefits of public services. To get there, though, I’m gonna have to lead you through a bit of the history of how humanity actually started keeping track of time in the first place.
In the beginning, there were Rocks. While humans have used rocks to make basic tools for our ~entire existence, the development of rock-based clocks reflects that societies had developed three foundational technologies in the civilization tech tree: 1. Math, 2. Astronomy, and 3. basic material working (measurements, joints, etc.), as well as an economy that is capable of supporting the both development & use of a timekeeping system; this began around 6000 years ago. From there, it was off to the races; once a culture had reached those critical thresholds, a seemingly overwhelming natural compulsion took hold to build a calendar and/or clock.
The Sumerians probably went first (although their role in our modern minutes and hours is disputed), but other cultures followed. The first sundials were built by the ancient Egyptians circa 1500 BC, but many other societies (incl. Babylon) were coming to the tech around that time. Societies put significant effort into constructing these rock structures (such as, e.g., Stonehenge or the Maya‘s various structures) which track the solar seasons, as well as into the simpler sundials for the daily time. A temple that marks the solstice doesn’t come cheap.
However, keeping time with rocks is not particularly accurate or precise (sundial says its about 2inches past midday), and does not work at night. They also are unique to the area they were constructed in, as the sun’s position in the sky changes depending on latitude. Nevertheless, these kinds of clocks are found throughout the ancient societies of the world, and are often some of the only surviving relics of those long-gone cultures; literally every great ancient society did this to some degree.
Later, various civilizations came up with the water clocks (like the Greek “Tower of the Winds“), which use pipes to regulate the flow of falling water, to track the passage of time more accurately. Sand hourglasses are a variation on this. Many societies implemented mechanisms where the weight of a water container, once full, would ring a bell which could be heard at a distance – these were the first clock towers, and, indeed, time signals. These were also the first clocks that didn’t just track particular days or astronomical events (like the solstice), or approximated time within the day like a sundial (assuming it wasn’t raining), but gave some semblance of precise/accurate measurement of intra-day time (and worked at night).
This wasn’t cheap in the Bronze Age
I could keep going but I’m not gonna quote the entire “History of timekeeping devices“, wiki, article, or otherwise, at you, you can read about ancient clocks (if you’re interested) on your own time, and I do think it’s a pretty interesting subject. You get what I am trying to illustrate here: since the dawn of civilization, societies have spent significant resources – in a very resource constrained period! – to keep track of the time, and to make the time available to the public. There are certainly many other timekeeping devices and structures that have been lost, from civilizations all over the globe; this is a universal human experience.
The costs to these societies shouldn’t be overlooked. In ancient Egpyt, the prevailing daily wage was the equivalent of 10 loaves of bread and 2 jugs of beer, and constructing a clock (or paying someone to maintain it) would cost many times that – a skilled craftsman would have to work for days to build a Clepsydra or Sundial. Yet we have dozens of examples of timekeeping devices from ancient Egypt. While the cost cannot be measured precisely in a non-monetary economy, it seems clear that timekeeping systems & services consumed significant resources for Egyptian society.
Keep in mind, these societies were not particularly technologically sophisticated, with primitive Bronze Age agriculture – yet all they all took significant time and resources to build these rudimentary clocks. Moreover, these civilizations had minimal-to-no contact with each other; China barely knew of the Greeks, but they still built water clocks. The Maya didn’t know the Egyptians, but they still built sundials. These were all separated by centuries and thousands of kilometers, and yet, they all built solar clocks and sundials, and later water clocks. Human civilizations are in no small part defined by creating a calendar system.
The other particularly universal human element here is that these were incredibly manual systems. Besides construction with hand tools, someone had to manually put the water back into those water clocks, for example. The word “timekeeper” currently describes an object (like a clock or watch), but it used to describe a profession – the person who maintained the clocks, etc. Pre-industrial societies were not only investing significant resources into building these things, but the opportunity cost of a person to run the clock. Someone wasn’t farming (or any other early civilizational tasks) if they were running the clock.
They did this because the benefits of having the time regularly kept (as best as possible) were clearly worth it. Societies all over the globe knew that they needed the benefits of timekeeping and were willing to pay these exorbitant costs (as a % of their national income) because the value derived was clearly worth it. Having Xeno put the water in the clock was clearly a better use of his time than having him weed the fields. But Xeno would probably also want to do other work – what if we could have the clock just run itself so he could do other things?
That’s my contorted lead into the modern era: industrial timekeeping.
Machines do the work now!
Water clocks were the pinnacle of timekeeping until the last ~700 years. A machine that could accurately tell the time, i.e. a clock, is a relatively recent invention in human history. (Remember when I said I was done quoting the history of timekeeping devices at you? I was lying.)
The first fully mechanized clocks, that is, clocks that did not keep track of time by “person lifts thing up and that weight, falling, in itself tells the time” weren’t even designed until sometime in the 13th century; we aren’t sure exactly when, but the Salisbury clock (which is still operating) dates to ~1386. For some perspective, Oxford University was founded by 1096, and Cambridge by 1209. (Can you be late for class if clocks hadn’t been invented yet?) Timekeeping began to merge into the profession of clock-maker: a person who was responsible for constructing, and maintaining, several of these large devices.
Most folks continued to rely on these publicly-available machines, which were installed in clock towers, for several hundred years after their development; home/office clocks didn’t become popular, or at least widely available, until the invention of the pendulum clock and its subsequent mass production. In a pendulum clock, the regular & predictable rhythm of a swinging pendulum advances the clock mechanism. First developed in the 1600s, these were the first clocks that could keep time accurately (as we understand the word) and could be manufactured relatively economically.
I’m using the term economically in a bit of a loose manner. Keep in mind, the industrial revolution is itself a relatively recent phenomenon in human history. It didn’t even start until the early 1800s, and mass production with interchangeable parts didn’t begin until circa 1870. Thus, mass-produced mechanical clocks for home or business didn’t supplant the clock tower as the source of time for the vast majority of people until the last ~150 years or so, and indeed, many other clock towers are far more recent for this reason; Big Ben dates to 1859, and its construction was both a statement after Westminster burned and a practical need for a clock tower in central London.
Industry enables Industry
The industrially-produced pendulum clock was the first opportunity where average people could actually keep the time in their own homes and businesses; my point being, the idea of being able to know what time it is in your own home is a phenomenon really only common to the last ~100yrs of industrial society. While still reliant on external sources to know what to set the clock to (we’ll get to that), the design of the clock and its subsequent mass production (both in Europe and in the US) made timekeeping affordable to the average person.
This was when time also really started to matter to the average person; you couldn’t exactly be late to something if nobody had clocks to judge your arrival by. The precision and reliability of the mass-produced pendulum clock made precise scheduling available to the average person, for work and for pleasure. Industrially-produced clocks themselves enabled industry: shift workers, precision-timed chemical processes, etc. were all made possible by the clock. Without clocks, there’s no capitalism (take that for what you will). Clock systems, like the Master clock and time clock, sprung up to take advantage of this accurate timekeeping.
However, technology did continue to advance. Pendulum clocks were the first clocks to be truly accurate as we would understand them today, and they were continuously improved upon until, in 1921, the Shortt-Synchronome clock was developed which was accurate & precise enough to track the gradual slowing of the Earth’s rotation. They were large, expensive (about £15,000 in today’s money), and only about 100 were built for national time services, but we’d finally gotten to the first truly modern clocks: accurately maintaining the current time down to the second (or better), for extended periods.
Additionally, mechanical clocks without pendulums (using springs instead) were developed. Accurate time is essential for determining position at sea (the “longitude problem“), and since these clocks could be used at sea (a rocking ship renders a pendulum clock useless), they are commonly called marine chronometers. The problem was so urgent that the UK Gov’t issued a £20,000 (£3.35m today) reward to the developer of the ship-based mechanical clock. The first successful design for them was submitted in 1761.
While these clocks weren’t as accurate as their pendulum-based, land-locked counterparts, they were good enough that ships could use them to figure out where they were. Shipping, as an industry, became far less perilous because of the chronometer; reliable transoceanic voyages enabled reliable international trading links. Shipping and exploration, as industrial endeavors, began around this time; James Cook used a chronometer on his second voyage.
The invention of the chronometer necessitated the invention of several other technologies, including bimetallic strips (in basically every thermostat ever made) and ball bearings. Their invention marked that Humanity had not just finally entered the mechanical timekeeping era, but our quest for accurate time had led to many incredible inventions that we still use today, and indeed began to link us closer together as a species – imports were now more regular and reliable.
Do you have the time? Which time?
This proliferation of mass-produced clocks led to a problem: how do you know what time to set it to? Most clocks in service are not perfectly accurate, and will drift over time (this is true even today). This is, obviously, a problem; you can’t have everyone just guesstimating that “it’s noon” and setting their clocks however/whenever. When there was literally just one clock in a tower somewhere, this wasn’t an issue: people were all referencing the same thing. Now there are multiple possible reference points, and with increasing precision, clock error & drift also started to matter.
The clock tower itself initially provided the first solution to this problem. People would just refer to the de facto standard they already had been using, and set their own clocks accordingly. This model of the public-service clock becoming the “official” time and all other clocks deriving their time from it is still what we use today; whether manually or automatically, all clocks are ultimately deriving their time from some other, more-reliable [I’m using the word reliably slightly loosely there – reliability takes many forms], and publicly-available, source.
This leads to a question of synchronization: how do you actually get the official time? In the clock tower days, it was relatively simple: just look at the tower. For obvious reasons, as cities developed and need for accurate time grew, this became impractical. It introduces human error, it limits the access to the “official” time to a small radius around the tower where the clock is actually legible (which is a lot smaller than you may initially think – Big Ben can’t be read from the other side of the Houses of Parliament). Therefore, governments recognized that there needed to be some system to actually distribute the time to clients that needed it: these are what we now call “time signals”.
This was most pressing for naval vessels and civilian shipping; as their chronometers were less accurate than a land-based pendulum clock, they were synchronized before every voyage, and governments provided publicly available time signals to do so since ships can’t often see a clock tower from the harbor. Before the invention of radio, this generally used a large ball that was dropped from atop a mast, visible from a great distance, at a precise time (typically, 1pm); this is where the tradition of a New Years Eve ball drop comes from. Other countries have comprable procedures, for example in Edinburgh, Scotland, an artillery piece is fired at 1pm daily from the castle over the harbor (as fog often obscured visible signals).
End of Part 1
Having reached mass production clocks and the very first time signals, I think now is a good time to pause. Thanks for bearing with me – I hope you enjoyed this. As always, my content is For the People, and I will never charge for it, but if you’d like to chip a couple bucks into the tip jar, I won’t say no. Additionally, just a reminder that this content exists both on my website and my substack.