around 5000B. C
The Origin of the Sundial
The oldest timepiece in history is the sundial. At first employing just a rod stuck into the ground, then later erecting stone pillars, ancient people used sundials to measure time from the position of the shadow cast on the ground.
around 1400B. C
The Origin of the Water Clock
Water clocks were invented as timepieces that could be used even when the sun was not shining. Designed to allow water to escape from a vessel at a constant rate, these devices were used to measure time by the level of the remaining water.
The Development of the Combustion Clock
Combustion clocks were used to measure time using materials that would burn at a constant rate. This included candle clocks, incense clocks, and lamp clocks. Some of these also provided the additional convenience of serving as a source of light.
The Practical Use of the Hourglass
- 1 second error in 20 seconds
Because hourglasses are not easily influenced by swaying or by changes in temperature, they were used for many centuries as a means of measuring time on sea voyages.