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D Walden,
Nice analysis running through  those sights in the old navigation workbook. I
did something similar for a few  other dates. Did you discover that the data
for many dates are calculated twice?  You can see that John Layton and his
wife Elizabeth each worked the numbers on  those dates. Also, if you would like
to estimate dip, the deck of the  Charles W Morgan is about ten feet above the
waterline, so height of eye should  be about 15 feet.

So in 1896, you take a morning or afternoon time sight  and shoot the Sun at
noon. The ship's position is fixed in as little as ten  minutes with simple
calculation. That's how it was done for decades on ships at  sea even as late
the 1940s. With all the talk recently on Sumner's method, I  think it's worth
remembering that Sumner's lines were considered a somewhat  exotic technique,
one that might never be used in months at sea. Celestial lines  of position
didn't catch on universally until almost a century after Sumner  published. And
why that was the case is still a fascinating  question...

On formatting, you wrote:
"Sorry for the garbled tables. I  didn't realize the list sever dropped
"extra" spaces!"

Your original  message came through fine in e-mail, but the list archives
(and some mail  readers) strip out formatting.

-FER
42.0N 87.7W, or 41.4N  72.1W.
www.HistoricalAtlas.com/lunars

   

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