Wristwatch/Timelines

3500 BC(E): The obelisk is created by Egyptians, and possibly previously by Sumerians 1500 BC(E): 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 theives") 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. 1525: 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