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Re: Worsley's Epitome
From: Brad Morris
Date: 2017 Feb 10, 12:32 -0500
From: Brad Morris
Date: 2017 Feb 10, 12:32 -0500
From my library
Log (cos (85°41'))=
Burton's "High Latitude Edition" (1937)
=8766 [4 place table]
Bowditch "Practical Navigator" (1849)
=87661 [5 place table]
Norie "Epitome of Practical Navigation" (1848)
=876615 [6 place table]
Atkinson "Epitome of the art of Navigation" (1753)
=9.998766 [7 place table, effectively 4]
Thoms "Practice of Navigation at Sea" (1856)
=87661 [5 place table]
Moore "Practical Navigator" (1828)
=876615 [6 place table]
On Feb 10, 2017 11:19 AM, "Lars Bergman" <NoReply_Bergman@fer3.com> wrote:
Robin, you wrote "I don't know what actually done to compute the tables but whether a 5-figure table gives 8.87661 or 8.87662 may depend on the exact method used".
Yes, that is true. However, I have checked a few 5-figure tables:
Roswall (1824), Bowditch (1851), Pettersson (1861), Lindman (1924); they all gives 8.87661.So if we can find a 5-figure table showing log cos 85°41' = 8.87662 then we have a good indicator of which table Worsley might have used. If not, then we have an indication that he used a 6-figure table.
Lars
