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Moore's Error Found by Bowditch
From: Gordon Talge
Date: 1999 May 09, 10:57 AM
From: Gordon Talge
Date: 1999 May 09, 10:57 AM
I finally figured it out. Here is what I think happened.
Declinations for the Sun are listed from 1791 to 1819. This is the
13th Edition dated 1798. There are 12 Tables arranged like this:
1) 1791, 1795, 1799, 1803 [1803 should not be listed here]
3rd yr after leap yr.
2) 1792,1796, 1800, 1804 [1800 should not be listed here]
leap yr.
3) 1800
4) 1801
5) 1802
6) 1803
7) 1804,1808,1812,1816
leap yrs.
8) 1806, 1810, 1814, 1818
2nd yr after leap yr.
9) 1807, 1811, 1815, 1819
3rd yr after leap yr
10) 1797
1st yr after leap yr
12) 1798
2nd yr after leap yr.
What I think goofed them up what that the pattern of 1-2-3-leap and start
over again got messed up because 1800 is not a leap year. They fixed it
in the tables with 1800,1801,1802,and 1803 having their own separate pages,
but on the labeling 1803 is also listed with table 1 and 1800 with table
2.
I also noticed that 1793 and 1794 were missing. They should be with
1797 and 1798 respectively. I think the reason that they are not,
is because the book is the 13th edition published Jan. 30, 1798. They
probably used the same printing setup as in past years and did not
want to reset the type and drop all years before 1797. But they did
do it for the current years 1797 and 1798, putting them on a page
by themselves.
The idea of the tables is that if you use a nautical almanac exactly
4 years out of date ( with exceptions ) you get the same declination.
-- Gordon
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| Gordon Talge WB6YKK e-mail: gtalge@pe.net |
| Department of Mathematics QTH: Loma Linda, CA |
| Notre Dame High School Lat. N 34� 03.1' |
| Riverside, CA 92506 Long. W 117� 15.2' |
| http://www.pe.net/ND |
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