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Care of Marine Chronometers


Dial View Negus Marine Chronometer
Negus Chronometer

Marine chronometers have become highly collectible.  Unfortunately, these historically important,  monetarily valuable instruments were never intended to be in hands unfamiliar with their operation.  They are NOT designed to be forgiving and  it is very easy to do extensive (expensive) damage.

The chronometer is not like a clock or watch where you can turn hands backwards or adjust the seconds hand with impunity.  The design of the escapement (the interface between the balance and the power train) is such that doing these things will likely result in serious damage.  On an "important" piece, this can result in a catastrophic loss in originality.

Many of these "fragile" chronometers have survived well over 150 years.  The explanation is quite simple.  Until quite recently, they were in the hands of those who knew how to handle them.

Every chronometer owner should own (and read) Marvin Whitney's Ship's Chronometer by AWI Press.  This book was first published in 1984 and has since gone out of print.  It is the bible of chronometers and must be found in the used book market.  


  • Turn hands backwards on a running chronometer
  • Stop or "adjust the seconds hands on a running chronometer
  • Let the chronometer be handled by those unfamiliar with it


  • Stop the chronometer balance with "wind still showing" when going away for the weekend
  • Wind the Chronometer Daily when in use
  • "Cork" the balance (see below) when the chronometer is leftA wedged Marine Chronometer for shipping not running





For shipping  or ordering information, contact:

Dewey Clark                   410.592.9998

Email Contact:         Historictimekeepers@gmail.com

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