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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Sight reduction
From: Steven Wepster
Date: 2003 Feb 12, 00:39 +0100
From: Steven Wepster
Date: 2003 Feb 12, 00:39 +0100
Dutch: I made a mistake here; upon closer inspection it appears now
that my tables (JC Lieuwen, Zeevaartkundige Tafels, 1949) are based on
methods of Souillagouet for altitude and on Dreisonstock for azimuth.
In the introduction Lieuwen states that he made some improvements:
azimuth can be found without using logarithms, and altitude can be found
for the DR position instead of for an auxiliary point, which apparently
was
considered as an awkward thing. The nautical triangle is divided in the
same
way as in Ageton's method, the difference lies in what functions are
actually
tabulated.
By the Japanese method I meant the procedure where you use a small flat
peace
of hardware; you only press the buttons; no more flipping of pages,
scribbling down of intermediate answers, or arithmetic errors. It's more
convenient but less fun.
I hope this is clearer.
Steven.
-----------------------------------------------------------
Steven Wepster wepster@math.uu.nl
tel +31 30 253 1531
Mathematisch Instituut
Universiteit Utrecht
PO Box 80.010
3508 TA Utrecht
The Netherlands
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On Tue, 11 Feb 2003, Marc Bernstein wrote:
> Just curious what the Dutch modified Ageton and Japanese methods are!?
>
