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    Re: How Many Chronometers?
    From: UNK
    Date: 2009 Sep 21, 22:46 -0700

    Hello from a frequent reader, but not a member of the list.
    I'm a former US Navy officer and did my sea time on destroyer types (Pacific 
    and Atlantic) in the NAVSAT (pre-GPS) days.  The ships had three mechanical 
    (wind-up) chronometers, gimbaled in their boxes - with dessicant - and placed 
    in a dedicated drawer in the chart room.  The drawer was on the ship's 
    centerline and the chart room was located behind the bridge.  Do keep in mind 
    that the chronometers were as useful as the decommissioned magnetic compass.  
    Time was kept via NAVSAT, compared daily with radio signal, and backed up 
    with the officer's wrist watches.  Sextant navigation was also a dead 
    practice, but that's another story.
    Back to the topic: my sea time coincided with the advent of affordable 
    accurate quartz wristwatches.  As an experiment on one of the ships, we rated 
    our two dozen watches instead of resetting to NAVSAT time.  The purpose was 
    to compare watch brands and purchase price.  We found the mid-priced watches 
    of two particular brands did as good as the expensive watches and all were 
    much more consistent than the ship's chronometers as long as we wore the 
    watch.  One unexpected result: the watches experienced an occasional "jump."  
    We suspected this was a result of the "jerk" accelerations the ship 
    experienced in pounding storm seas.  Each watch had a different jump, but the 
    ship's chronometers had the same jump - the chronometers were the same brand 
    but of different ages.  I wonder if, twenty years later, today's affordable 
    watches are still susceptible to the jerk.  I can say that my modern Casio 
    watch is much more accurate and consistent than my "good" Citizen watch of 
    twenty years ago.  One second in two years for the $30 Casio (landlocked).
    [Sent from archive by: joseph_schultz-AT-rrv.net]
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