Wristwatch/Timelines

3500 BC(E)

• The Obelisk is created by Egyptians, and possibly previously by Sumerians.

1500 BC(E)

• The Sundial/Shadow Clock built by Egyptians
• One of the earliest water clocks is buried in the tomb of Egyptian pharaoh Ahemhotep 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.

1300s CE(AD)

• Mechanical clocks appear in Italian cities, in towers.

1500 - 1510

• Peter Henlein of Nuremberg invents the spring-powered clock.

1656

• Christiaan Huygens (Dutch) invents the first pendulum clock.