-
1600 BCE
Sun watch
Egyptians
Shadow -
1000 BCE
Water watch
Speed of water for a hole
Clepsidra ( Greece ) -
700
Sand watch
Hour to hour
Turning it over -
1290
Mechanical watch
Progress
Based on weight engine
Rewind the thread -
Pendulum clock
Pendulum sistem
Exact -
Stopwatch development
15 degrees = 1 hour -
Electronic clock
Energy
So exact -
Atomic watch
H. Lyons
Independent of external factors -
Digital watch
Similar atomic
Screen -
Smartwatch
Computer
2013 ( massive market )
