3500 BC(E): The obelisk is created by Egyptians, and possibly previously by Sumerians
- The sundial/shadow clock is built by Egyptians
- One of the earliest water clocks is buried in the tomb of Egyptian pharaoh Ahemhotem I
500 - 100 BC(E):
- Romans and the Greeks improve water clocks through mechanics (bells, gongs, doors -- ways to attempt flow regulation)
- 325 BC(E) - clepsydras' ("water thieves") are used by the Greeks
30 BC(E): Vitruvius describes 13 different types of sundial styles in Greece, Asia Minor, and Italy
1 BC(E): Andronikos constructs the Horologion, the "Tower of the Winds" in Macedonia, Athens Marketplace
200 - 1300 CE(AD):
- Chinese inventors modify clepsydras' to drive various mechcanisms.
- 725 CE (AD) - A water escapement is invented in the far east
- 900 CE(AD) - Pocket sundials are employed
- 1088 CE (AD) - Su Sung implements a water escapement in the "Su Sung clock tower". It is over 30 feet tall and very elaborately adorned.
1300 CE(AD): Mechanical clocks appear in Italian cities, in towers.
1500 - 1510: Peter Henlein of Nuremberg invents the spring-powered clock.
- Jacob Zech of Prague invents the fusee
- Gruet also works on and perfects the fusee
1582: Galileo creates the pendulum-clock concept, but wasn't able to build it before his death.
1656: Christiaan Huygens (Dutch) invents the hair-spring, about the same time as Hooke from England
1671: William Clement of London begins to build clocks with an "anchor" or "recoil" escapement
1675: Huygens creates the Balance Wheel and spring assembly
1704: Nicholas Facio (Swiss) introduced Jeweled bearings
1721: George Graham creates a pendulum that adjusts for temperature change
- John Harrison builds a marine chronometer with a spring and balance wheel escapement that wins the British Government's prize established in 1714.
- Harrison also develops friction reduction techniques during the 1760s
1764: John Harrison builds the Gridiron pendulum
1888: Friedrich Reinitzer of Austria discovers the liquid crystal property
- Siegmund Riefler builds a nearly free pendulum clock that become standard in astronomical labs
- Otto Lehmann coins the term "liquid crystal" inspired by Reinitzer's work
1895: Seiko in Japan creates the first Japanese pocketwatch
1898: R. J. Rudd develops the first true "free pendulum clock"
1913: Seiko in Japan creates the first Japanese wristwatch, dubbed "The Laurel"
1921: W. H. Shortt develops another true "free pendulum clock"
- G. W. Pierce's research on Crystal Oscillators lays the groundwork for Cady to develop the Crystal Oscillator
- 1923+, Walter Guyton Cady develops the first Crystal Oscillator
1927: Warren Marrison develops the first quartz crystal oscillator clock
1940: The Swiss establish the Laboratoire Suisse de Recherches Horologeres (LSRH)
1946: The Hamilton Watch company develops the "Hamilton Electric 500" between 1946 and 1957. It is an abysmal market failure due to a flawed design, and short battery life.
1955: Max Hetzel of Switzerland creates prototypes of watches using Tuning Forks as opposed to the balance wheel.
1961: Seiko Japan creates the 951, their first quartz crystal chronometer
1962: The Swiss establish the Centre Electronique Horloger (CEH)
- From the CEH come Quartz watch prototypes
- Seiko Japan sells the 953 Pocketwatch and Wristwatch, both Quartz powered
1968: Juergen Staudte creates a process for mass production of quartz oscillators while working at North American Avionics (which became Rockwell)
1969: Seiko Japan sells the 35SQ Astron, the first commercially available quartz watch on Christmas, December 25th
- From the CEH comes the Beta 21, on sale April 10 1970, a quartz crystal watch
- The Pulsar, a joint product between Hamilton and Electrodata is announced on April 4; developed by John Bergey and Dick Walton
1972: The Pulsar is on the Market