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: 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

       
    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