-
3000 BCE
OBELISK
Egyptians told the time by the shadow cast by an unmoving object. An obelisk is a vertical structure with 4 sides. By placing it in the sun, it casts a shadow that changes position throghout the day. -
1500 BCE
WATER CLOCKS
The early Greeks and Egyptians designed a water clock/clepsydra that used the flow of water to measure time. In the early versions water flowed through a very small hole in one container through to a bowl shaped container beneath it. As water reached the horizontal lines marked on the bowl shaped container, people were able to track the passage of time. -
520 BCE
CANDLE CLOCK
A candle clock was a thin candle that when burned, indicated the passage of periods of time. Candle clocks provided an effective way to tell time indoors, at night, or on a cloudy day. First a candle was burned to see how long it would last and then candles of similar thicknesses had notches made. Each notch represented a period of time. It is unknown where and when candle clocks were first used. The earliest known reference to their use is in a Chinese poem by You Jiangu (520 CE). -
300 BCE
SUNDIAL
Sundials were first used by people in Babylonia. This was a falt circle on which a 12 hour clock face or dial had been written. It had a gnomon attached - a vertical marker - in the middle. The gnomon cast a shadow on the dial as the position of the sun changed. -
1000
HOURGLASS
The hourglass was one of the first timekeepers that was not dependant on the sun. The first hourglasses were two separate bulbs with a cord wrapped at their union that was then coated in wax to hold the pieces together and let sand flow in between. The hourglass was portable and accurate and measured units of time from minutes to hours. -
1300
MECHANICAL CLOCK WITH WEIGHTS
Mechanical clocks with weights first began appearing in Europe. These clocks used weights and balances to mark out time over a 12 hour period. They were not very accurate. -
1400
PORTABLE MECHANICAL WATCH
The first portable mechanical watches appeared in Italy and measured time through a series of coiled springs.The portable watch could be placed in a pocket or hung by the belt and had a flip top lid, which when lifted revealed the time. -
MECHANICAL CLOCK WITH PENDULUM
A pendulum clock is a clock that uses a pendulum, a swinging weight, as its timekeeping element.The pendulum was added to the mechanical clocks to control the clocks mechanism in order to increase its accuracy and preciseness. This clock was able to record minutes, hours and seconds. This clock was invented in 1656 by Christiaan Huygens and was used up until the 1930s. -
INTERNATIONAL DATE LINE
The U.S., Canada and Great Britain all agreed to set the International Date Line to help standardise the telling of time across all countries. -
QUARTZ CLOCK
The quartz clock was built in 1927 by Warren Marrison and J.W. Horton. The device is battery powered and the gears within the clock that measure the passing of time do so through a quartz crystal instead of a pendulum. This means that gravity has no effect on these clocks, and the time remains the same throughout the world. -
ATOMIC CLOCK
The atomic clock was built at the U.S. National Bereau of Standards. It remians the most accurate time keeping device to date. It works with atoms as opposed to most other clocks which are mechanical. Atomic clocks count how many times an atom wiggles back and forth. Over 260 atomic clocks exist around the world. -
QUARTZ WATCH
The first quartz watch entered production in 1969. It was much more accurate than a mechanical watch. The watch contained a quartz crystal, a hard and galssy mineral called silicone dioxide.
