NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: No Lunars Era
From: Frank Reed CT
Date: 2004 Dec 6, 18:52 EST
From: Frank Reed CT
Date: 2004 Dec 6, 18:52 EST
I think that my point may not have been clear (or that it was easy to
misinterpret) in the original post in this thread. I am not trying to suggest
that lunars were not used. They were. But they were used in a very different
fashion from what many people suppose. In the period before chronometers became
common, there was no "lunars era" in which lunars were the PRIMARY method of
determining longitude for most navigators. Instead, lunars were treated as a
check on the dead reckoning, something to consider IN ADDITION TO the longitude
by dead reckoning which was the primary longitude for the vast majority of
navigators.
Starting in the 1830s there is a "sea change" (you could also call it a
"paradigm shift") in the way navigators recorded and discussed their longitude.
The longitude by chronometer was "it" for most navigators. They used dead
reckoning only for brief periods of a day or two when observations were
impossible. And for a few decades they continued shooting lunars as occasional
(typically twice a month) checks on the longitude by chronometer. This is a
radical change from the earlier period when the dead reckoning was carried
on for months at a time.
Frank R
[ ] Mystic, Connecticut
[X] Chicago, Illinois
[ ] Mystic, Connecticut
[X] Chicago, Illinois