Evolution of clock face design and its personal impact
The most common analogue clock face these days is a 12-hour round dial, typically with hour, minute, and sometimes second hands that sweep around a circular face with numerals or markers. Though 24-hour dials are also in use, they are seen less frequently.
Behind the modern clock design, there is a long history of timekeeping device evolution (which readers can get acquainted with later in the article). From ancient sundials to contemporary clocks, each device had unique methods of displaying time. The design of the first mechanical clock dials from 14th-century Europe was heavily influenced by astrolabes and sundials. Initially, these clock faces displayed all 24 hours of the day. Over the centuries, the 12-hour format became increasingly widespread and was established as the standard by the time of the Industrial Revolution.
Despite variations in clock face designs, they generally follow a common pattern: the dial is a flat round static surface divided into equal segments with hands rotating clockwise, mimicking the movement of the gnomon’s shadow in horizontal sundials. It is an almost universal convention to place the start of the day or another significant marker at the top of the dial. Once again, this practice is likely inherited from sundials, where noon is marked at the extreme point between the sunrise and sunset hours. In modern 12-hour dials, the top indicates both midnight and midday, while in 24-hour dials, it can signify either, with midnight typically being more common.
In addition to being inherited from older timekeeping instruments, positioning the start of the day at the top of the clock face is intuitive. When a circle is divided into equal parts, the four extreme points are most prominent, with the top being the most conspicuous. This can be attributed to our tendency to read from top to bottom or to the top point appearing as the pinnacle and zenith of the shape. Hence, it only seems natural to place the most important hour benchmarks at that position.
The clock face design is so deeply ingrained in modern culture that people often don't even need numerals to indicate the hours; they can tell time from the position of the clock hands alone. To an extent, it can be argued, the prevalence and familiarity of the design influence the way we perceive the flow of time during the day. Historically, the day has been split into two periods — before and after noon — which is reflected in the design of clocks, and those designs in turn visually reinforce our mental model of the day.
The number 12 is a significant marker on the clock. It signifies the end of one period and the beginning of another, and in that aspect is not so different from, say, a Monday or a January. These new beginnings, as arbitrary as they are, have the ability to shape our behaviour. Just like people wait for a Monday to start going to the gym or for January 1st to adopt a new healthy habit, they might wait for noon or midnight to begin or end their tasks. Reflecting on my personal experiences, this tendency makes it harder for me to get going and stay active in the morning. Starting a new activity at 10 or 11 am just doesn’t seem right when you know the 'am' period is going to be over soon. So in that manner, the period before noon on the dial seems in a way as almost invisible ‘leftovers’, and the day only seems to really kick in after 12 o’clock, when putting off starting a new task feels less justifiable. Needless to say, this can cause some inconveniences in daily life.
To see if I could alter my perception of daytime and consequently change my behaviour, I decided to try a small experiment. Using a standard 12-hour mechanical clock placed in my room, I rotated the hour numbers so that 8 was at the top of the dial, with the rest of the numbers following clockwise as usual (the minute markers were unchanged). My hope was that by positioning 8 at the most prominent place — the pinnacle of the dial — I could make this hour be perceived as more significant and structure the rest of the day around it. This way, 8 o'clock (the time I aim to start my days) would become a new landmark, making it easier for me to be more active in the mornings, while the emphasis on 12 would be diminished, breaking up the established day structure. In this manner, the day can appear to be split into two parts: an ‘active’ period from 8 am to 8 pm, and a period of ‘rest’ from 8 pm to 8 am, which better aligns with my routine.
Over the next few weeks, I noticed a shift in my perception; time indeed seemed to have shifted forward, allowing me to see the day with a fresher perspective and deemphasising my pre-existing mental models. This created a greater sense of urgency in the mornings, giving the impression that more of the day had already passed, meaning that my goal was partially achieved.
However, it has to be said that this effect is most noticeable when actively looking at the clock and less significant when away from it. The original design remains deeply embedded in my consciousness, and when thinking about time, it is still the old design that I visualise in my mind. Perhaps with repeated exposure to the new clock face or other intense familiarity training, this perception might change and the ingrained picture will start to soften and shift. Nevertheless, this experiment was a helpful opportunity to take a look at my daily routine with fresh eyes and gain a new perspective. When we can so often be stuck in our habits, it can be valuable to get a new outlook to be more mindful of the present moment. So, the clock will keep on being a nice accessory in my room.
Alternative design approaches
There are, of course, plenty of other ways in which the clock face can be modified. Using the same approach of rotating the dial, different numbers can be placed at the top. Positioning 6 o’clock at the top can be a rather straightforward choice; after all, many cultures had a custom of counting days from the time of sunrise or sunset. Besides, this way the dial is rotated by a pleasantly regular 90°. The general idea of this method is to place the hour you want to draw the most attention to at the top position of the round clock dial; then the rest of the numbers will structure themselves around that focus point. Using a full 24-hour dial here instead of a 12-hour one can also be useful, since in that case the whole circumference of the day is clearly visible and the hour hand gives an unambiguous daytime indication, creating more clear temporal awareness.
Another approach to altering the design can be to make the clock hand static and the numbered dial rotating instead. This way, the current hour is always at the top of the clock face, which makes the focus on the present moment even more prominent. It can be said that this design is essentially not so different from a digital clock indicator, since in both cases it is the numerals that carry the crucial information, but arguably the presence of a circular dial showcasing all hours adds a spatial element to the design, which aids in a more tangible perception of time since the whole length of the day is visibly on display.
Potential use cases
While the common 12-hour clock face design emerged for good reasons and will undoubtedly remain the standard, especially whenever coordination between multiple people is required, there is room for experimentation with user experience in specific contexts and potential for imagining how our everyday experiences could be enhanced by time being displayed contextually. In situations where quickly and reliably telling time is crucial, conventional clock dials are necessary (nowadays, mostly digital), but in scenarios where there is space for playing around with viewers’ perception of time and through that enhancing their experiences, altered designs could potentially be useful.
Experiences can be crafted that allow people to curate a customised flow of daytime and add a personalised touch to their routine by adapting the clock face to their particular needs and preferences. Alternatively, these modified time indicators can be imposed on viewers externally whenever the designer wants to draw special attention to certain time periods. In either case, the viewer will be forced out of their familiar mental model by an unexpected time indicator and encouraged to pay more mindful attention to the flow of time and the present moment.
It would be interesting to explore how people of different ages would respond to similar modifications in clock face designs. Recent reports suggest that younger generations, who have grown up mostly with digital clocks, often struggle with reading analogue faces, raising questions about how they view the time flow. Still, since they are less influenced by pre-defined ideas, maybe contextual clock interfaces would be even more useful for them. As we move further and further into the digital era, it wouldn't be surprising if the ways we perceive time evolve accordingly.
While the existing clock face design conventions are conventional for good reasons and are perfectly usable and useful in most situations, there is room for artful experimentation in creating enhanced and personalised user experiences in both digital and analogue spaces. Modifying traditional clock designs may not be particularly practical in most everyday scenarios, but it can be used to enrich experiences by setting the right ambience. Here we have explored some variations of the clock face design, but other alterations can be imagined, and these don’t have to be limited to the round dial format. Design changes like these can break up the conventional conceptions and invite viewers to engage with time in a novel way.
Clock faces throughout history
Timekeeping devices have a long history of design conventions. Throughout history, cultures across the world developed various means of dividing the day into parts, accurately (or not so accurately) measuring those time periods, and displaying that information to viewers. As diverse as these techniques were, overtime conventions and standards emerged. Nowadays, the most common analogue clock face is a 12-hour round dial, although in many places it has already been replaced by a digital clock.
Dividing time
Currently, an hour is commonly defined as the 1/24th part of a day. In turn, each hour contains 60 minutes, and each minute contains 60 seconds. What seems like such a familiar system to us is, in fact, not a self-evident structure. Since ancient times, different cultures have adopted different systems for splitting time into countable periods that best suited their needs and customs.
An obviously self-defined interval of time to us, living creatures, is the day itself — the time it takes for the Earth to make one revolution on its axis — easily observable by the change of night and day. This repeated cycle forms the basis of calendars and clocks alike. While it is easy to then split the cycle into two parts, day- and nighttime, the manner in which time can be further subdivided is contentious.
Ancient Egyptians used to divide daytime into 12 ‘hours’. As the length of daytime outside of the equator is longer during summer and shorter during winter, the hour length also varied throughout the year. There is no sure way to tell how and when the duodecimal (base-12) system originated, but it is likely that it was influenced by observations of natural phenomena, e.g., 12 full lunar cycles in a solar year. Similar to daytime, night was also split into 12 parts by Egyptians, giving us 24 hours in a day altogether. The Greek and Roman cultures adopted the Egyptian hour system, although they also had a tradition of splitting nighttime into 3-4 parts (watches) before fully settling on 12 hours. Over time, Greek astronomers transitioned from using variable seasonal hours to fixed-length hours in their calculations, a practice that Western and then global culture inherited.[1][4]
In another major centre of ancient culture and science, the Babylonians had a similar system: the entire day was divided into 12 kaspu (also often called ‘double hours’). Alternatively, the day was divided into 60 equal parts, which were then further subdivided into 60 smaller parts and so on. The sexagesimal (base-60) system, which originated in the ancient Mesopotamia region, still remains in use today, most notably in the division of an hour into our familiar minutes and seconds.[1]
Throughout Chinese history, several different ways of dividing time coexisted. One manner of time division was the shi-ke 時–刻 system, where the day was split into 12 equal shi 時 (double hours) or into the smaller units of 100 ke 刻 (historically, the number of ke varied; 1/100th of the day would be our 14 minutes 24 seconds). Alternatively, the geng-dian 更–點 system split the day into 10 geng 更 (2.4 modern hours) or 60 dian 點 (24 minutes). Later, at the end of the Tang dynasty, the shi 時 was further subdivided in half, giving us the equivalent of the modern hour. The time unit characters from these systems are still in use in modern China, although their meaning has altered over time to represent the modern time standards.[5]
In the traditional Japanese temporal time system, daytime and nighttime were divided into 6 parts each. The ‘hour’ length was seasonal and varied throughout the year.[6]
The traditional Hindu timekeeping is a complex system based on vast astronomical and religious heritage. Commonly, a form of the sexagesimal system was used, and the day was split into 60 parts (24 modern minutes each), which were then subdivided into 60 more. The day could also be divided into 30 parts (48 minutes), a useful time unit close to the modern hour.[4]
During the French Revolution, the French government made an attempt to switch timekeeping to a decimal (base-10) system as part of a general decimalisation of measures programme. Under this system, the day is divided into 10 decimal hours, which are in turn divided into 100 decimal minutes, those into 100 decimal seconds, and so on. Its use began in 1794, but the impractical system was short-lived and lasted only a few years. Nowadays, variants of decimal time are used in some scientific contexts.[7]
Splitting the hour into 60 minutes is a rather modern invention, which nonetheless has roots back in the Babylonian astronomy and their sexagesimal system. Early clock faces could subdivide the hour into smaller parts but not into 60th since the mechanisms simply weren’t precise enough to make such small intervals practical. Clocks displaying minutes started to appear at the end of the Middle Ages once clock accuracy began to improve.
Timekeeping devices
Throughout the ages, numerous ingenious devices were employed for measuring time periods, from ancient primitive shadow clocks to today’s extremely sophisticated atomic clocks, with precision gradually improving over time.[2][8]
The sundial and its variations are reportedly the first time-measurement tools used by humans, the earliest ones discovered in Egypt dating back to 1500 BC. These devices tell the time of the day by tracking the position of the sun’s shadow on a marked surface. Ancient Greek sundials were highly sophisticated instruments that were later adopted by the Romans, who refined and integrated the technology into their own timekeeping practices. While plane dials are the most common type of sundial face, featuring a flat surface where the gnomon casts a shadow to indicate the time, sundials can also be constructed in other shapes such as spherical dials, which use a curved surface to project shadows.[2][9]
The water clock, also known as a clepsydra, keeps time by measuring a regulated flow of water either into or out of a container. This device, first documented in ancient Egypt and widely used across many cultures, remained the most precise timekeeping method until innovation allowed for the development of accurate mechanical clocks in the late Middle Ages. Medieval Islamic water clocks, in particular, showcased remarkable sophistication and innovation in their design.[2][3][10]
Another type of common continuous timekeeping device were incense and candle clocks (and less widely used oil clocks). In principle similar to the water clock, they measure time by the rate of combustion of incense powder or wax. The incense clock, first developed in China during the 1st millennium and later adopted by neighbouring countries, offered a convenient method for indoor timekeeping, often with different scents denoting specific hours. Meanwhile, candle clocks were utilised in both Eastern and Western societies, providing a simple yet effective way to measure time by burning candles marked with intervals.[11][12][13]
The hourglass, presumably invented in Europe during the Late Middle Ages, quickly became a reliable time-measuring device, especially valued for its accuracy at sea where traditional clocks were impractical. Widely used in daily life, the hourglass served purposes like cooking, religious rituals, and medical practices, becoming a durable and effective timekeeping instrument.[14]
The mechanical clock, thought to have originated in medieval Europe, marked a significant advancement over earlier timekeeping devices, offering unprecedented accuracy and reliability. Early weight-driven clocks were complex devices primarily used in public spaces, gradually evolving with significant innovations. Over time, advancements such as the invention of the mainspring (15th century) and the pendulum (17th century) greatly enhanced their precision. The principle of oscillation introduced by early mechanical clocks remains a fundamental aspect of modern timekeeping methods.[2][15][16]
Originating in the mid-19th century, the first electric clocks were electromechanical, using electrically driven pendulums. Subsequent innovations, such as the addition of a tuning fork and the invention of quartz crystal oscillators, greatly improved device accuracy. By the 1940s, quartz oscillation became the timekeeping standard, leading to the widespread use of highly precise quartz clocks today. These advancements have made electric clocks the most common type of analogue timekeeping device in modern times, known for their reliability and minimal maintenance. Atomic clocks are the current international timekeeping standard and are used as a benchmark for calibrating other clocks worldwide. The first highly accurate atomic clock was constructed in London in 1955, marking a significant milestone in timekeeping. These clocks use vibrations of atoms to maintain an extraordinarily consistent frequency, ensuring exceptional accuracy.[17][18][19]
Portable timepieces have been around since the 16th century, starting with pendants and pocket watches, which were initially quite inaccurate. Over time, technology allowed for smaller and more precise watches to be made, which led to their booming popularity during the 19th century. Historically, wristwatches were mainly seen as a feminine fashion accessory, while gentlemen preferred to carry a pocket watch. Wristwatches entered men’s fashion during the wars in the beginning of the 20th century, when they were recognised to be a very convenient military tool. Since then, the wristwatch has been a universally popular accessory and tool, which in recent years is being supplanted by the smartwatch that offers diverse capabilities far beyond traditional timekeeping.[20]
These days, digital clocks are the most widespread timekeeping devices, typically synchronised to atomic clocks for accuracy. These digital timepieces are found in a variety of everyday devices such as smartphones, smartwatches, and laptops, making precise timekeeping an integral part of modern life.[21]
Counting hours
Over the centuries, methods by which different cultures counted the hours and marked the start of the day — be it at sunset, sunrise, midnight, or midday — varied greatly. These differing approaches have significantly shaped the design and functionality of timekeeping devices, driving the evolution of the modern clock face.
Seasonal or relative hours, which adjust the duration of an hour according to the seasonally changing length of daylight, were a practical time-measuring method used by many cultures for a long time. It was customary to divide the daytime and nighttime into 12 hours each, with the day start often aligned with sunset or sunrise. This old tradition occasionally still echoes today in practices such as Jewish halachic hours and the Christian liturgical day. The ancient Egyptians began their day at sunrise, which is a straightforward and observable time marker. The Romans established their civil day starting at midnight, contrasting with the natural day, which was also in use and ran from sunrise to sunset. Roman sundials were used to keep track of these hours.[1][2][3][22]
The concept of equinoctial hours, which divide the entire day into equal parts, while known in the ancient world, was primarily used by astronomers. The astronomical day was typically counted from noon, the most observable solar event.[1][3]
During the Medieval period, Europe adopted the Roman system of hours, though the canonical hours played a more crucial role in daily life. These hours, which regulated prayer times, were a lot more relevant for the average person when scheduling their daytime. The medieval day was measured from sunset, as it still is in the Christian liturgical day. While the classical 12h sundial was still in use, a new type of sundial — a tide dial (also called mass or scratch dial) — emerged (not to be confused with tide clocks[23]). It was widely spread around England and western European countries between the 7th and 14th centuries, by which point it was replaced with a mechanical clock. Tide dials, often found on church facades, had the canonical hours marked prominently on them, sometimes with further subdivisions into the regular Roman hours. Hours were usually not numbered.[3][24]
The first mechanical clocks, developed in the 13th century, were striking clocks designed to ring out the canonical hours (the word clock derives from the medieval Latin word for 'bell' — clocca). These early timepieces likely did not have dials. When dials were eventually added, they featured a 24-hour format, a design likely influenced by astrolabes and horizontal sundials, with the clockwise movement mirroring the way a sundial operates. Initially, some early clocks had a fixed hand with a rotating dial, but by the late 14th century, the design evolved to include rotating hands and a static dial.[15][25]
Starting in the 14th century, mechanical clocks encouraged adoption of equal-duration equinoctial hours. Constructing a mechanical clock that could accurately measure changing seasonal hours would be costly (although occasionally still attempted). Still, for some time both systems coexisted in Europe since seasonal hours were often more convenient in daily use; the relative hours survived in normal use until the later Middle Ages. Some early astronomical clocks displayed both equal and unequal hours. As equinoctial hours gradually became the norm, the practice of counting the day from midnight or noon became more practical, though for some centuries there were two distinct systems that coexisted and competed in Europe: one with the day starting at midnight and the other one at sunset.[1][26]
The first public mechanical clocks introduced in Italy divided the day into 24 hours starting from sunset — a rather convenient design that helped people keep track of the remaining daylight available for working. Their face design placed the 1-hour mark on the right side, a feature that might have been inspired by sundials, where noon is displayed at the top and sunset near the left. This 24-hour timekeeping system remained in use until the mid-18th century.[26]
Northern parts of Europe instead of numbering all 24 hours of the day used a double 12-hour system with the day starting at midnight, following the old Roman practice. During the 15th and 16th centuries, this 12-hour analogue dial and timekeeping method gradually became the standard for public use across Northern Europe. During that time, the design evolved into the modern 12-hour clock format, where the dial repeats twice a day with noon and midnight marked at the top, and this system was fully standardised during the Industrial Revolution.[26][27]
Although the French effort to decimalise time did not succeed, some 10-hour clocks were nevertheless produced during that era.
The modern 24-hour analogue clock is a relatively modern invention, emerging in the late 19th century as an adaptation of the German system. Typically, noon or midnight is positioned at the top, with midnight being more common. Today, this format is used primarily in specialised contexts like military and healthcare.
While the 24-hour time notation system is today the global standard and is widely used in digital clocks, the 12-hour time system is still commonly used in English-speaking countries and in casual conversation globally.
References
- A history of time by Leofranc Holford-Strevens
https://archive.org/details/historyoftime00holf - Time & timekeepers, including the history, construction, care, and accuracy of clocks and watches by Willis I. Milham
https://archive.org/details/timetimekeepersi00milhuoft - History of the hour : clocks and modern temporal orders by Gerhard Dohrn-van Rossum
https://archive.org/details/historyofhourclo0000dohr - https://en.wikipedia.org/wiki/Hour
- https://en.wikipedia.org/wiki/Traditional_Chinese_timekeeping
- https://en.wikipedia.org/wiki/Japanese_clock
- https://en.wikipedia.org/wiki/Decimal_time
- en.wikipedia.org/wiki/History_of_timekeeping_devices
- https://en.wikipedia.org/wiki/Sundial
- https://en.wikipedia.org/wiki/Water_clock
- https://en.wikipedia.org/wiki/Incense_clock
- https://en.wikipedia.org/wiki/Candle_clock
- https://en.wikipedia.org/wiki/Oil-lamp_clock
- https://en.wikipedia.org/wiki/Hourglass
- https://en.wikipedia.org/wiki/Clock
- https://en.wikipedia.org/wiki/Astronomical_clock
- https://en.wikipedia.org/wiki/Electric_clock
- https://en.wikipedia.org/wiki/Quartz_clock
- https://en.wikipedia.org/wiki/Atomic_clock
- https://en.wikipedia.org/wiki/History_of_watches
- https://en.wikipedia.org/wiki/Digital_clock
- https://en.wikipedia.org/wiki/Roman_timekeeping
- https://en.wikipedia.org/wiki/Tide_clock
- https://en.wikipedia.org/wiki/Tide_dial
- https://en.wikipedia.org/wiki/Clock_face
- https://en.wikipedia.org/wiki/24-hour_analog_dial
- https://en.wikipedia.org/wiki/12-hour_clock
