Welcome to the NavList Message Boards.

NavList:

A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding

Compose Your Message

Message:αβγ
Message:abc
Add Images & Files
    or...
       
    Reply
    Re: 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




       
    Reply
    Browse Files

    Drop Files

    NavList

    What is NavList?

    Join NavList

    Name:
    (please, no nicknames or handles)
    Email:
    Do you want to receive all group messages by email?
    Yes No

    You can also join by posting. Your first on-topic post automatically makes you a member.

    Posting Code

    Enter the email address associated with your NavList messages. Your posting code will be emailed to you immediately.
    Email:

    Email Settings

    Posting Code:

    Custom Index

    Subject:
    Author:
    Start date: (yyyymm dd)
    End date: (yyyymm dd)

    Visit this site
    Visit this site
    Visit this site
    Visit this site
    Visit this site
    Visit this site