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Hello Bruce,

It has been a while since we've been in touch. Hope all is well with you.

A quick question re: your note below. I was not involved in last years'
discussion so you would do me a favour and provide us with a "Reader's
Digest" version of re: Greenwhich mean time.

cheers,

Robert.

P.S. all of these discussions are making me feel very guilty about not
practicing my lunars for such a long time.


----- Original Message -----
From: Bruce Stark 
To: 
Sent: Saturday, February 01, 2003 3:52 PM
Subject: Re: 1851 Bowditch


> Fred,
>
> One thing we've often been told the old navigators couldn't do was get
> latitude if they missed the noon observation. They had a number of ways of
> doing that. Any two altitudes of the sun we could use for a fix would give
> them their latitude. Local time too, if they wanted it.
>
> And, do you remember what we went through on the list last year in order
to
> convince people they didn't need accurate Greenwich time to calculate
> accurate altitudes? It started last winter as I recall, and the problem
kept
> coming up.
>
> The main thing to keep in mind when you read that 1851 Bowditch is that
you
> are in a different world. Celestial navigation as we know it would have
been
> useless. It requires that you know Greenwich time before you can work your
> observations successfully. Our celestial navigation, and the nautical
> astronomy Bowditch knew, are two different animals. Key words and phases
had
> different meanings then. Don't jump to conclusions when you read that 1851
> "Navigator." Follow through, work the "problems," and see what Bowditch
DOES.
>
> Bruce
>

   

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