Welcome to the NavList Message Boards.


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

Compose Your Message

Add Images & Files
    Re: An artificial horizon opportunity?
    From: David Pike
    Date: 2017 Jan 29, 02:37 -0800

    Randall you wrote: For an artificial horizon I use a first surface mirror on a round metal plate. It is adjusted on 3 screws with 40 TPI. Using 2 spirit levels I routinely get less than a mile accuracy in any wind. Ahmundson used this in his polar explorations. Instructions for making the levels are posted in the archive.

    Did Amundsen always use a mirror?  I always thought that at the South Pole at least he poured liquid mercury into a tray.  Carefully stored it would probably still be liquid.  Photo and text here http://www.southpolestation.com/trivia/igy1/polesurvey1.html (photo possibly taken earier in the jourey), but I could be persuaded that you can’t always believe everything you see and read on the www.  I've also read that he took a mirror and a spirit level as stanby in case the mercury froze  https://www.theguardian.com/notesandqueries/query/0,,-1024,00.html  DaveP

    Browse Files

    Drop Files


    What is NavList?

    Join NavList

    (please, no nicknames or handles)
    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 Settings

    Posting Code:

    Custom Index

    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