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
    Chronometer question.
    From: George Huxtable
    Date: 2006 May 13, 07:42 -0500

    Greetings, NavList members, from George.

    I'm after a bit of real help, to answer a silly question that has been
    bugging me.

    It comes from a log of a whaling voyage, to the Greenland sea, between
    Spitzbergen and Greenland, in 1818.

    It is really very simple.

    Departing from Shetland, with its Northerly point in sight, at a
    certain time-by-chronometer, an alt. of the Sun (supposing the N. end
    of Shetland to lie in long. 38'W) gave the Chronometer slow of
    Greenwich 3 minutes 39 seconds ...

    However, even in British home waters, the less-frequented parts had
    not all been well surveyed by 1818, and the charts carried may have
    been somewhat defective. Anyway, a modern atlas puts the N end of
    Shetland at about 0 deg 50' W, rather than 0 deg 38' W as had been
    assumed; quite a difference.

    In the light of that information, what should the chronometer error
    have really been?

    Of course, working out the AMOUNT of the necessary change is a rather
    trivial exercise. What I find to be challenging is working out the
    DIRECTION to apply that correction. Each time I sit down and work
    through the logic of it, my brain gives me opposite results. It's
    certainly not rocket-science, this one, but it's got me close to
    banging my head on the wall.

    Is anyone else prepared to have a shot at it? Really, there are only
    two possible answers, so there's a 50% chance of being right just by
    guesswork. That being so, as they say in the exams, extra marks will
    be given for showing your working. That would certainly make it more
    useful to me.

    George.

    contact George Huxtable at george@huxtable.u-net.com
    or at +44 1865 820222 (from UK, 01865 820222)
    or at 1 Sandy Lane, Southmoor, Abingdon, Oxon OX13 5HX, UK.



    contact George Huxtable at george@huxtable.u-net.com
    or at +44 1865 820222 (from UK, 01865 820222)
    or at 1 Sandy Lane, Southmoor, Abingdon, Oxon OX13 5HX, UK.


    --~--~---------~--~----~------------~-------~--~----~
    To post to this group, send email to NavList@fer3.com
    To unsubscribe, send email to NavList-unsubscribe@fer3.com
    -~----------~----~----~----~------~----~------~--~---

       
    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