Timeline Let's take a trip through time, from the epoch when farmers told time by looking at the sun to today, when atoms tell us the time. Sundial first used in Egypt to measure the time of day by the sun's shadow.
Hours are shorter in winter and longer in summer.
Click for information on making a sundial. Candles and burning incense mark time in China. 1400s mechanical clocks are built in Europe, using a mainspring and balance wheel. As ships are sinking due to not knowing their location, Philip II of Spain offers a reward for a method of finding longitude at sea. 1583 Galileo Galilei realizes that the frequency of a pendulum's swing depends on its length.