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    Re: what is a second?
    From: Bill B
    Date: 2006 May 9, 22:50 -0500

    Good question as to whom invented the whole system. As a start, visit


    "The sexagesimal (base-sixty) is a numeral system with sixty as the base. It
    originated with the ancient Sumerians in the 2000s BC, and was transmitted
    to the Babylonians."


    > I ask this question of the list, after having looking into time divisions 24
    > hour day, 60 minute hour and 60 second minute but how the second was defined
    > eludes me.   I have seen that a pendulum of 1 meter length has a period of a
    > second so if that is how the second was defined I am ok with it.
    > Still I wonder if the definition of the second might have preceded the metric
    > system defintions?
    > The problem as I see it is that  to have a clock of accuracy in the seconds,
    > before electricity, quartz, and atomic, there had to be some way to decide how
    > long a second should be.  Also there had to be some way to set ones instrument
    > or clock so that the second reflect the divisions of the day with some
    > reasonable accuracy.    I  dont have a problem with  variations in  the rate
    > of  a clock  since that is easily compensated.
    > Longitude being the measurement affected particularly by variations in the
    > length of the second and the number from uct.
    > So to recap, when was the second defined and when was it possible to create
    > instruments that could count off seconds accurately?

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