The History of the Watch

The Origins of Timekeeping: Ancient Methods and Celestial Observations

The earliest form of timekeeping, shared universally among humanity, was based on the rhythms of the world in which we live. The movements of the sun, moon, and stars enabled early humans to mark the passage of days, weeks, and seasons.

In fact, the concept of a twelve-hour day and a twelve-month year originated from Babylonian culture, which associated the number twelve with mystical or divine elements. Various methods of timekeeping emerged among ancient cultures, including shadow- and sun-based techniques.

Herodotus attributed the invention of the sundial to the Babylonians, and existing examples from thousands of years ago can still be found across different cultures. The sun’s journey across the sky, the phases of the moon, and the movement of constellations served as humanity’s earliest clocks and calendars.

From primitive yet ingenious shadow sticks to more complex sundials and obelisks, these early instruments were not just tools but also symbols of a growing understanding of the universe and our place within it.

The first devices to directly measure the passage of time were water clocks. There is evidence that timekeeping methods evolved outside of Europe, with different designs and functionalities seen in ancient Persian water clocks.

A basin with a small hole would be filled with water, and the water level at the edge of the basin as it drained would indicate the passing of time. Nearly all early timekeeping devices were discovered near the equator, in places such as Babylon, Egypt, Greece, Persia, and other warm, sunny regions.

Ancient civilizations like Babylon and Egypt pioneered timekeeping to schedule shipments, agricultural tasks, and lunar events. The ancient Egyptians, using shadow and sundials, were among the first to divide the day into measurable segments. Egyptian obelisks, built around 3500 BCE, are among the earliest recorded shadow clocks.

The oldest known sundial also comes from Egypt, estimated to date back to around 1500 BCE. These shadow devices relied on the sun’s position to indicate time changes. Around 2000–1500 BCE, the Egyptians began dividing day and night into 12 roughly equal parts. This time division survived to the present day after being adopted by the Greeks and later the Romans.

Other civilizations also developed unique methods of timekeeping. Meanwhile, the Mesopotamians and Babylonians took a different approach. Their complex lunar calendar, interwoven with astrology, laid the groundwork for many modern timekeeping concepts. The influence of these civilizations persists even today.

The sixty-second minute and sixty-minute hour are legacies of the Babylonians, who used a sexagesimal (base-60) system to divide the day. In the Far East, ancient China pursued precision in timekeeping in a different form.

The Chinese developed intricate water clocks, culminating in the astronomical clock tower of Su Song around 1092 CE. Su Song’s water clock stood as the most accurate timekeeper in the world for centuries. In the classical Greek and Roman worlds, timekeeping extended from temples and royal palaces into public life.

Wealthy citizens carried sophisticated mechanisms, such as the Antikythera mechanism discovered in 1901, which tracked not just time, but also the sun, moon, and planetary movements. Across the seas, the Maya and Aztecs developed calendars with astonishing accuracy, deeply connected to their cosmology and agricultural cycles.

In addition to sundials, water clocks (also known as clepsydrae, meaning “water thief” in Ancient Greek) were among the earliest advanced timekeeping devices. One of the oldest examples was found in the tomb of Egyptian Pharaoh Amenhotep I, buried around 1500 BCE.

This clock used regulated water flow from one container to another to measure time. The Greeks began using them around 325 BCE, adapting them with dials and hands. Water clocks were more useful than sundials because they could be used indoors, at night, and on cloudy days, although they were initially less accurate.

Later improvements increased their precision, and some even included alarms. In Asia, alternative timekeeping methods appeared around 520 CE—such as candle and incense clocks. Candle and incense clocks endured for centuries, even into the 1920s.

By measuring how long a candle or stick of incense took to burn, people could estimate the passage of hours. Hourglasses, composed of two glass bulbs connected by a narrow neck, became popular from the 15th century onward, particularly at sea due to their reliability and ease of use.

Ingenious Inventions of Early Civilizations: From Sundials to Water Clocks

The ancient Egyptians demonstrated early mastery of timekeeping. They not only divided the day into measurable segments using shadow and sundials, but also developed the oldest known astronomical instrument, the merkhet, around 600 BCE.

The merkhet was used in pairs to determine the north-south line by aligning with the Pole Star, allowing nighttime hours to be marked by observing other stars crossing the meridian. The importance of timekeeping in ancient Egyptian life is reflected in its use for organizing agriculture, religious ceremonies, and even labor for pyramid construction.

The Babylonians and Mesopotamians made foundational contributions with their sexagesimal number system, which used 60 as its base. This system, dating back to around 2000 BCE, still influences our modern understanding of time, with 60 seconds in a minute and 60 minutes in an hour. The Babylonians’ choice of 60 reflected its mathematical versatility—it’s divisible by many whole numbers, making calculations and conversions between time units easier.

In ancient China, the pursuit of timekeeping precision culminated in the development of complex water clocks. Su Song’s astronomical clock tower, built around 1092 CE, was regarded as the world’s most accurate clock for centuries. It did more than display the time; it represented a harmony between technology, governance, and the cosmos, playing a vital role in daily life and imperial rituals. The Chinese were also among the first to use candle clocks, with the earliest recorded mention found in a Chinese poem from 520 CE.

Greek and Roman civilizations adopted and refined timekeeping methods from earlier cultures. They made extensive use of sundials and water clocks, and the Greeks even created an early prototype of the alarm clock around 250 BCE, using a clepsydra that triggered a mechanical whistle as the water rose.

Wealthy citizens in the Greco-Roman world also carried sophisticated devices like the Antikythera mechanism, capable of tracking time and celestial movements. The spread of timekeeping from temples and palaces into public life reflected a growing societal awareness of and need for precise time measurement in daily activities.

In Mesoamerica, the Maya and Aztecs developed calendars with extraordinary accuracy, deeply integrated with their cosmology and agricultural cycles. Their complex and sophisticated timekeeping systems reflect a deep understanding of astronomical cycles and their terrestrial effects.

The Mechanical Revolution: The Birth and Evolution of Gear-Driven Clocks

The first mechanical clocks appeared in Europe around the early 14th century. Some scholars credit the earliest true mechanical clock to a European weight-driven tower clock built around 1283 CE. Others argue the first mechanical clock was created in China around 1092 CE by scholar and engineer Su Song.

Regardless, it is widely agreed that the first weight-driven clock was constructed in Bedfordshire, England, in 1283 under the strong patronage of the Roman Catholic Church. This clock used an oscillating flywheel escapement to indicate hours, though it failed to show minutes.

Curiously, despite earlier Chinese advancements such as escapements, mechanical clocks never became widespread in China. However, when Europeans introduced mechanical clocks to China in the 17th century, they became extremely popular due to the exquisite craftsmanship and precision that fascinated the Emperor and his court.

Tower clocks, which emerged in the first half of the 14th century, were weight-driven and regulated by verge-and-foliot escapements. These early clocks often lacked dials and hands, indicating time by striking bells. Monasteries were among the earliest users, employing these clocks to organize their daily routines.

The invention of mechanical clocks marked a significant technological leap, providing a timekeeping method independent of natural phenomena and with the potential for greater accuracy. The shift from continuous processes (like water flow) to oscillatory processes (like the verge escapement) was critical to more accurate time measurement.

Initially, the absence of dials showed that communal time signaling was the primary purpose rather than personal precision. These clocks’ societal impact began to shape a more time-conscious culture through the standardization of time and improved punctuality.

Early mechanical clocks included three essential components: a power source (weights), a regulator (foliot balance), and an escapement (verge and crown wheel). Weight-driven mechanisms, though reliable, were bulky and immobile, limiting portability. The foliot, while regulating speed, was not isochronous, causing inaccuracies.

The verge escapement, the first mechanical escapement, also introduced friction, further limiting precision. By the 14th century, mechanical clocks had spread widely across Europe, often mounted on church towers. Spring-driven clocks appeared between 1500 and 1510, enabling the creation of smaller, portable timekeepers.

The growing presence of mechanical clocks in public spaces signaled their increasing civil importance as community timekeepers. The invention of the mainspring was a major step toward personal timepieces.

Perfect Precision: The Rise of Pendulum, Quartz, and Atomic Clocks

The pendulum clock, invented by Christiaan Huygens in 1656 based on earlier research by Galileo, significantly improved accuracy, reducing errors to less than one minute per day. Pendulum clocks revolutionized timekeeping, marking a major advancement in horology and enabling more precise scientific observations and navigation. The pendulum’s “natural” oscillation period offered a more consistent and reliable timekeeping mechanism than the verge escapement.

This increase in accuracy was vital for fields such as astronomy and the development of marine chronometers to determine longitude at sea. The invention of the minute hand in 1577 by Jost Burgi and Huygens’s balance spring around 1675 further enhanced accuracy, allowing portable watches to tell time with errors of around 10 minutes a day. Marine chronometers developed in the 18th century by figures such as John Harrison were essential for accurate navigation.

The first quartz clock was developed in 1927 by Warren Marrison. Quartz clocks used the vibration of quartz crystals to generate electrical signals, offering far greater accuracy than mechanical clocks. The invention of the quartz clock marked another giant leap in timekeeping accuracy and paved the way for widespread use of highly precise and affordable timekeepers.

The piezoelectric properties of quartz provided a more stable and consistent frequency standard than mechanical oscillators. This led to the development of electronic timekeepers, which would eventually dominate the market. Atomic clocks, invented in the mid-20th century, used atomic vibrations to measure time with extraordinary precision.

Today, atomic clocks are the standard for international timekeeping. They represent the pinnacle of human achievement in horology, achieving levels of accuracy previously unimaginable and crucial to modern technologies like GPS and telecommunications.

The use of atomic vibrations—a fundamental constant of nature—provides the most stable and accurate timekeeping mechanism known. This level of precision is vital for synchronizing global systems and conducting advanced scientific research.

Clocks and Society: Their Profound Cultural and Organizational Impact

Mechanical clocks had a deep impact on society by regulating daily activities in monasteries and later spreading to secular life, shaping a culture organized by time. The standardization of time through mechanical clocks led to a more structured and predictable society, influencing labor, commerce, and social interaction.

The ability to measure time accurately and consistently enabled fixed working hours, improved punctuality, and facilitated coordination across different locations. The shift from natural rhythms to mechanical time had a profound effect on human awareness and social organization.

Mechanical clocks also spurred innovations in engineering and metallurgy. The quest for more accurate clocks drove technological advancement. Clock development served as a catalyst for broader technological progress, pushing the boundaries of precision engineering and manufacturing.

The intricate mechanisms required for accurate timekeeping led to improvements in gear systems, escapements, and other mechanical components with applications in various other fields.

Clocks became symbols of prestige and artistic expression, with elaborate designs and decoration. Clock towers became prominent landmarks. Beyond their practical function, clocks acquired cultural significance, representing wealth, power, and mastery over time.

Ornamental craftsmanship on many clocks reflected the value placed on these objects as status symbols and works of art. The prominence of clock towers in urban landscapes symbolized civic pride and the importance of time in public life. Clocks enabled precise measurement, facilitating scientific observation and exploration.

Marine chronometers were essential for navigation. Accurate timekeeping was vital for scientific advancement, enabling more precise experimental measurements and fostering key innovations in navigation.

The ability to determine longitude at sea—made possible by accurate marine chronometers—revolutionized seafaring and global trade. Precise timekeepers also played a key role in astronomical observation and the development of physics.