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: Simple celestial navigation in 1897
    From: Frank Reed CT
    Date: 2006 Mar 2, 22:24 EST

    D Walden,
    Nice analysis running through  those sights in the old navigation workbook. I
    did something similar for a few  other dates. Did you discover that the data
    for many dates are calculated twice?  You can see that John Layton and his
    wife Elizabeth each worked the numbers on  those dates. Also, if you would like
    to estimate dip, the deck of the  Charles W Morgan is about ten feet above the
    waterline, so height of eye should  be about 15 feet.
    
    So in 1896, you take a morning or afternoon time sight  and shoot the Sun at
    noon. The ship's position is fixed in as little as ten  minutes with simple
    calculation. That's how it was done for decades on ships at  sea even as late
    the 1940s. With all the talk recently on Sumner's method, I  think it's worth
    remembering that Sumner's lines were considered a somewhat  exotic technique,
    one that might never be used in months at sea. Celestial lines  of position
    didn't catch on universally until almost a century after Sumner  published. And
    why that was the case is still a fascinating  question...
    
    On formatting, you wrote:
    "Sorry for the garbled tables. I  didn't realize the list sever dropped
    "extra" spaces!"
    
    Your original  message came through fine in e-mail, but the list archives
    (and some mail  readers) strip out formatting.
    
    -FER
    42.0N 87.7W, or 41.4N  72.1W.
    www.HistoricalAtlas.com/lunars
    
    
    

       
    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