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Re: chronometer dials: 12 or 24 hours?
From: Dan Allen
Date: 2009 Jan 20, 14:46 -0700
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From: Dan Allen
Date: 2009 Jan 20, 14:46 -0700
On Sun, Jan 18, 2009 at 3:45 PM, Paul Hirose <cfuhb-acdgw@earthlink.net> wrote:
Chauvenet (1863) said chronometers should have 24 hour dials, because
the AM/PM ambiguity of a 12 hour dial made it more difficult to read the
correct Greenwich time. See the footnote on this page:
http://books.google.com/books?id=6JlzJHd15vQC&pg=PA56&output=html
So I got on the web to see if later ones had 24 hour dials. After
looking some pictures at this site, I guess that wasn't the case, at
least for the common American chronometers:
http://www.chronometer.net/
I have a solar powered watch that has a rotating slide rule outer bezel. It contains three inner dials, one of which is a 24-hour dial showing GMT/UTC time. This is a modern watch called the Citizen Blue Angels Skyhawk, made in Japan.
Dan
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