NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
A Lunar from 1825
From: Frank Reed CT
Date: 2004 Aug 5, 01:24 EDT
From: Frank Reed CT
Date: 2004 Aug 5, 01:24 EDT
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mysticseaport.org/library/initiative/PageImage.cfm?PageNum=160&bibid=34575
It's a journal entry from March 26, 1825. It shows one complete lunar distance calculation done by hand with a standard approach from that period. This is the raw "scratch" work done on an empty page in the back of the book with almost no labeling, and if you don't know lunars from stock prices, you might never guess what you were looking at.
At the top of the page it says March 27 Sea Account and there's no year given that I can see, but this journal includes entries in the early to mid 1820s so it was a simple process of elimination. By using my lunars almanac (the "Lunars Predictor" on www.HistoricalAtlas.com/lunars ), and setting the time to Greenwich Apparent Time, it was not too hard to find the date that closely matched the entries from the published Nautical Almanac which are marked on the right hand side of the page.
But note how short this calculation is: a lunars calculation AND the corresponding time sight all on one page with plenty of room to spare!! These things were NOT difficult, and they were not time-consuming.
So here's the fun part: which method is this navigator using to clear his lunar?
Frank R
[ ] Mystic, Connecticut
[X] Chicago, Illinois
mysticseaport.org/library/initiative/PageImage.cfm?PageNum=160&bibid=34575
It's a journal entry from March 26, 1825. It shows one complete lunar distance calculation done by hand with a standard approach from that period. This is the raw "scratch" work done on an empty page in the back of the book with almost no labeling, and if you don't know lunars from stock prices, you might never guess what you were looking at.
At the top of the page it says March 27 Sea Account and there's no year given that I can see, but this journal includes entries in the early to mid 1820s so it was a simple process of elimination. By using my lunars almanac (the "Lunars Predictor" on www.HistoricalAtlas.com/lunars ), and setting the time to Greenwich Apparent Time, it was not too hard to find the date that closely matched the entries from the published Nautical Almanac which are marked on the right hand side of the page.
But note how short this calculation is: a lunars calculation AND the corresponding time sight all on one page with plenty of room to spare!! These things were NOT difficult, and they were not time-consuming.
So here's the fun part: which method is this navigator using to clear his lunar?
Frank R
[ ] Mystic, Connecticut
[X] Chicago, Illinois
