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    Re: The Bygrave
    From: Hanno Ix
    Date: 2009 Aug 5, 09:16 -0700

    Maybe I have misunderstood your question?  If so, sorry.

    My point was that the scales of the Bygrave are sometimes useful in calculations with certain other trig functions than those it was originally designed for.


    --- On Wed, 8/5/09, douglas.denny@btopenworld.com <douglas.denny@btopenworld.com> wrote:

    From: douglas.denny@btopenworld.com <douglas.denny@btopenworld.com>
    Subject: [NavList 9365] Re: The Bygrave
    To: NavList@fer3.com
    Date: Wednesday, August 5, 2009, 6:44 AM

    You have lost me.

    The scale in the pdf file appears to be logTan to me (or, if you wish -as marked, logCotan which is the same as logtan inverted, so divisions per degree are the same in either case) and is, as expected, extended at the 0 degree and 90 degree ends with the minimum divisions per degree at 45 degrees.

    For use with a Bygrave slide rule a logCosine (or logSecant)is needed; (separately).

    Douglas Denny.
    Chichester. England.

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