-
300
1500-1300 BC
Sundial first used in Egypt -
400
400 BC
Greeks use a water clock -
Jul 10, 1370
1370
King Charles V of France decrees that all Paris church bells must ring at the same time as the Royal Palace, helping end the ringing of bells at prayer time decreed by the church. -
Jul 10, 1400
1400s
The mechanical clocks are built in Europe, using a mainspring and balance wheel. -
1583
Galileo Galilei realizes that the frequency of a pendulum's swing depends on its length. -
1657
Christiaan Huygens invents the first pendulum clock, capable of far greater accuracy than any preceding timekeeper. But the clock does not work at sea. -
1759
John Harrison builds a clock, that loses only 5 seconds on a voyage from England to Jamaica. -
1839
Telegraph invented, allowing instant transmission of time signals. -
1840s
Time ball is dropped at noon each day at the U.S. Naval Observatory. Ships in the harbor use the ball to set their clocks. -
1884
Twenty-five countries accept Greenwich, England, as the prime meridian (0 degrees longitude). The prime meridian gradually becomes the basis for time throughout the world. -
1886
Salespeople for the R.W. Sears Watch Company fan out across America selling affordable timepieces. The firm is later renamed Sears, Roebuck and Co. -
1905
A radio time signal starts being transmitted from Washington DC to help ships find longitude. -
Present
Time is more popular than ever: about half-a-billion watches are sold each year. -
980
Alfred the Great uses burning candles to measure time.