Timeline of time measurement technology

Timeline of time measurement Technology

270 BC - Ctesibius builds a popular water clock, called a water clock

46 BC - Julius Caesar and Sosigenes develop a solar calendar with leap years

1000s - Sets of hourglasses were maintained by ship s pages to mark the progress of a ship during its voyage

1000s - Large town clocks were used in Europe to display local time, maintained by hand

1335 - First known mechanical clock, in Milan

1502 - Peter Henlein builds the first pocketwatch

1582 - Pope Gregory XIII, Aloysius Lilius, and Christopher Clavius introduce a Gregorian calendar with an improved leap year system

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1656 - Christian Huygens builds the first accurate pendulum clock

1676 - Motion works and minute hand introduced by Daniel Quare

1680 - Second hand introduced

1737 - John Harrison presents the first stable nautical chronometer, thereby allowing for precise longitude determination while at sea

1850 - Aaron Lufkin Dennison starts in Roxbury, Mass.U.S.A. the Waltham Watch Company and develops the American System of Watch Manufacturing.

1884 - International Meridian Conference adopts Greenwich Mean Time for consistency with Nevil Maskelyne s 18th century observations for the Method of Lunar Distances

1928 - Joseph Horton and Warren Morrison build the first quartz clock

1946 - Felix Bloch and Edward Purcell develop nuclear magnetic resonance

1949 - Harold Lyons develops an atomic clock based on the quantum mechanical vibrations of the ammonia molecule

*1999 - Launch of data clock for measurement societal time and design of timescapes

2008 - Launch date for the Primary Atomic Reference Clock in Space.

See also: clock