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Subject: Re: Carry on, Mr. Bowditch
From: Jan Kalivoda (jan.kalivoda@XXX.XXX)
Date: Thu Jan 16 2003 - 04:15:59 EST
Dear David,
let me try to answer your questions one by one.
It is absolute nonsense that before Bowditch, the lunars were useful to
seamen only in the moments of a star occultation by Moon. In contrast,
occultations were never used for navigational purposes at sea. The only
theoretical reason for using a sextant for observing occultations is its
telescope - but to use a the stand-alone one would be more simple. In this
point the Bowditch story you have cited is quite unreliable and ridiculous.
You must hope that in other things it is correct, but ... (I didn't read
it.)
The assertion that only Bowditch's method made the use of lunars possible
for ordinary seamen is motivated by the national pride a bit. Of course, it
is claimed in all editions of American Practical Navigator I have known. It
is only matter of taste and nationality.
If you search for a clear and precise explanation of lunars, take the text
of George Huxtable (in four parts) that has been published in this list as
the best. If you want, I can send it to you privately. A bit of spherical
astronomy and trigonometry is necessary for understanding it, of course. If
some elucidation without any computations and formulas is wanted in this
list, I can try it.
A trial for a summary of relations between lunars and chronometer methods
during the past (including the impact of chronometer prices) was sent to
this group by me - I excuse me for referring to myself:
http://www.irbs.com/lists/navigation/0301/0054.html
Yours, Jan Kalivoda
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