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
    Name or NavList Code:
    Re: 40+ year ambition achieved
    From: David C
    Date: 2016 Jul 24, 22:16 -0700

    "Cloudy Weather" contains log sec, log cos and half log haversine tables. The tables are four figure and involve interpolation. By rewriting the hav formula it is possible to solve a time sight without Norie. I reworked one of the time sights and the difference in logitude between the Norie and "Cloudy" calculations was 6'. Maybe if I work the sight again and take more care with the interpolation the difference will be reduced.

    I did not have much luck with using the "Cloudy" tables for multiplication and division. The errors were large. The numbers involved are three digits so it would be more accurate and almost as quick to use long multiplication and division. In the explanation to the tables there are some hints which suggest that I am not using them correctly. I will need to follow it up.

    In summary, if your copies of  Norie, 3270, 229 and your plotting instruments have been washed overboard but you are a collector of antique books your copy of "Cloudy" will get you home.

    Browse Files

    Drop Files


    What is NavList?

    Get a NavList ID Code

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

    A NavList ID Code guarantees your identity in NavList posts and allows faster posting of messages.

    Retrieve a NavList ID Code

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

    Email Settings

    NavList ID 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