The History of Timekeeping

Sundial

Clepsydra

Astrolabe

Candle Clock

Sandglass

Mechanical Clock

Spring-Driven Clock

Pendulum Clock

Quartz Clock

Cesium Atomic Clock

Sundial

During the 16th century BC in a town in Egypt, gnomons which are shadow casting devices were used to divide the day up into large intervals. These gnomons were eventually combined with scales to produce a sundial. The sundial enabled people to tell time based on the length or direction of the shadow cast by the sun. Back then, sundials were very inaccurate. This was partly due to the fact that many people had not acknowledged that the summer hours are longer than those of the winter. Sundials were made based on the area in which it was to be used because the Sun farther away from the equator is lower in the sky than it is when the Sun is closer to the equator. This affects the length of the Sun’s shadow which therefore affects the understanding of whatever time it may be.

Make your own sundial here