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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: � � � Re: David Thompson's Navigational Technique
From: Fred Hebard
Date: 2004 May 31, 15:23 -0400
From: Fred Hebard
Date: 2004 May 31, 15:23 -0400
Yes indeed, the famous error that Bowditch took much credit for correcting (and still takes, 203 years later!). BTW, I wonder if someone could refresh our memories on Bowditch's contribution to methods of clearing the lunar distance. Was he one of the first to present an "approximate" method such as Frank Reed recently described? Fred On May 31, 2004, at 3:03 PM, Bruce Stark wrote: > The plot thickens. > > I was reading George's post again, and didn't skim over the part > where he says "Wouldn't an angle of 24" in lunar-distance convert to > 48" (not 12") in time, which would convert to 12 minutes (not 3 > minutes) of longitude?" That's been cleared up now. But since he was > right, I wanted to work the observations and try to figure out what > was going on. > > Just as Thompson may have done, I turned to a 1796 edition of Moore > for the sun's declination. But after taking the declination out (of > Table XVII for the years 1792, 1796, 1800, and 1804) I noticed some > small print in the table heading: "Each being Leap-Year." An alarm > went off. > > The point is, 1800 was not a leap year. It isn't divisible by 400. > Wasn't this the cause a big foofaraw, and a humiliation for Moore? For > Oct. 11th the declination is given as 7? 24' south. For Oct. 12th, 7? > 47' south. Is that correct? > > Bruce