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- Any device that can be used to measure time
- though usually meaning a timepiece which uses
- a train of cogs and wheels driven by a spring
- controlled by a balance wheel or a weight on
- a pendulum.
- A Sundial is a clock and a primitive form of
- this,called a Shadow-clock,was used by the
- ancient Egyptians during the day.A Water-
- clock being used during the night.
- Until the 16th. century sand-clocks in the
- form of hour-glasses were used at sea(by the
- Royal Navy until about 1820).
- Watches are portable clocks.The first one
- being invented in the early 1500's in
- Nuremberg.
- The first English public clock was erected
- on Salisbury Cathedral in 1386 and is
- still working.
- The device has developed from these early,
- primitive,forms,via the Electric clock,to
- the Quartz clock(using crystals) and thence
- to the Atomic clock which is accurate to
- within one millionth of a second a day.
-