NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: A simpler Bygrave ?
From: Hanno Ix
Date: 2010 Feb 7, 14:43 -0800
From: Hanno Ix <hannoix@sbcglobal.net>
To: NavList@fer3.com
Sent: Fri, February 5, 2010 4:43:47 PM
Subject: A simpler Bygrave ?
From: Hanno Ix
Date: 2010 Feb 7, 14:43 -0800
Gentlemen:
So far I have not received any answers why a single scale Bygrave never has been implemented. I suspect it has to do with the use of such a thing, however, it is not clear to me. However, I am no sailor.
There must be some of you so knowledgeable in CelNav who have an opinion. Please, just drop me a note.
Regards
H
PS, again: in the formulae below x=1...89; should be replaced by x=(1:89)/180*PI
From: Hanno Ix <hannoix@sbcglobal.net>
To: NavList@fer3.com
Sent: Fri, February 5, 2010 4:43:47 PM
Subject: A simpler Bygrave ?
Ageton's method can be, mathematically at least, performed with a single scale, log cosec or log sec.
Therefore, it should be possible to create a version of the Bygrave that contains just a single scale of cosec or sec.
For convenience, one could add one or more cursors as convenient.
Note: The CelNav on Starpath's Emergency Navigation
Card can be reduced to this method.
Just compare their N(x) Table with : n(x) = logn(cosec(x)) for x=1...89;
I can see certain mechanical advantages of a one-scale Bygrave. I am sure this has occurred to somebody else long ago, too.
Therefore I ask why, despite its seeming simplicity, such a version has never been implemented.
Regards
