The history of the clock is a long and occasionally disputed one, originating many centuries ago and charting the route from simple observations of the sun to the modern digital alarm clock.
The word “clock” was first used in the 14th century and comes, via Dutch, Northern French, Latin and Celtic origin, from the word, “clocca”, the Latin word for bell.
Pre-14th Century
Thousands of years ago, people used the very inaccurate method of observing the movement of the sun to determine whether the day was nearer sunrise or sunset.
Its lack of precision led to the invention of the sundial around 3,500 BC. This more accurate method proved very popular, with its main drawbacks being the sun’s path across the sky changes daily because of the Earth’s axis and the changeable rate of the sun’s movement throughout the year. This meant although the sundial was more accurate than mere observations of the sun, it was still limited in its accuracy. Added to this, it only worked with the sun and was therefore pretty useless at night.
Time was also measured by various methods of burning, using things like candles or incense, which burn at predictable rates, as well as hourglasses which measure the time it takes for sand to fall through from one container to another.
By 1,400 BC, the Egyptians had invented the clepsydra, or water clock. The water clock told the time according to a water level as the liquid fell from a high container to a lower one.
The Greeks improved on the design and also came up with the idea of dividing the year into months and days to make telling the time more accurate.
The Egyptians and Babylonians then decided to make it even more precise by splitting the days into hours, minutes and seconds. But they initially divided the days into two 12 hour blocks, meaning that the water clocks had to be adjusted every day to take into account the changing hours of daylight during the year. It was only when someone realised they could split the day into 24 hours of equal length that telling time and the use of clocks became even more accurate and set the basis for modern clocks.
By the 13th century, different inventions had appeared and been adapted in an attempt to find an accurate method of telling time. These involved the controlled release of power, from water for example, which was used to ring a bell or alarm. Due in part to further advances made by a Muslim engineer from Turkey, Al-Jazari, the world witnessed the start of automatic time-telling machines.
The Modern Clock
In 1510, Peter Henlein of Germany invented a spring-powered clock but it lacked precision. This was improved slightly 67 years later when a clock with a minute hand was invented by Jost Burgi, but it remained fairly inaccurate by modern standards.
It wasn’t until the middle of the 17th century that the pendulum was used to help maintain some kind of accuracy. Developed by Christian Huygens, the pendulum clock added a second hand by the end of the century.
The first mechanical alarm clock was invented by Levi Hutchins of Concord, New Hampshire, in 1787. However, the ringing bell alarm on his clock could ring only at 4 am. 99 years later, a mechanical wind-up alarm clock that could be set for any time was patented (#183,725) by Seth E Thomas.
On early pendulum clocks, the pendulum used to swing a lot and as designs were improved it swung a lot less. But while the clock was becoming more accurate, the problem of powering them was the next difficulty. They would work well for a while but then had to be restarted. As a means of overcoming this, a pendulum clock with external batteries was developed around 1840. By 1906, the batteries were inside the clock.
The development of electronics in the 20th century meant that no clockworks were needed at all. Time in these cases was measured in several ways, such as by the vibration of a tuning fork. To improve the accuracy still further, quartz crystal clocks were invented in the 1920s by Warren Marrison, a telecommunications engineer. Quartz vibrates at a constant rate so when electricity is applied to it, it’s unlikely to lose time easily. Other methods included the decay of radioactive elements, or resonance of polycarbonates. Mechanical clocks have since come to be largely powered by batteries, completely removing the need for winding.
The use of hands on a standard clock face has also become obsolete with the introduction of the digital clock (which also brought the 24-hour clock) and the use of auditory rather than visual clocks for convenience or to overcome problems of distance or blindness.
Is there anywhere clocks can go from here? Only time can tell.
Sources:
(1) http://www.arcytech.org/java/clock/clock_history.html
(2) http://inventors.about.com/od/cstartinventions/a/clock.htm
(3) http://en.wikipedia.org/wiki/Clock
