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
    Burton's "Nautical Tables, High Latitude Edition"
    From: Brad Morris
    Date: 2013 Feb 16, 21:37 -0800

    A few years back, while browsing in a used book store, I came across Burton's Nautical Tables, High Latitude Edition". I do not know the publish date for the standard portion of the tables, but the appendix, wherein the "ex-meridian and ABC tables are extended" to latitude 82 degrees is dated 1937.

    The book was very inexpensive and due to my interest in the high latitudes, I bought it. It has rested on my shelf ever since.

    Not only does the ex-meridian table extend latitude to 82 degrees, it also extends the declinations to 75 degrees. This table is for the values of F, and must be worked with the standard components of the exmeridian table in the main tabular reference.

    The pupose of the ex meridian table is fairly straight forward. It is provided such that you can determine your latitude should the meridian crossing by your object (typically the sun) be obscured by clouds.

    Much less obvious to me are the ABC tables. There is a footnote explaining that the A&B portions were first published in 1846, and that the C portion was invented by Mr. AC. Johnson.

    Can someone explain what the purpose(s) are of the ABC Tables? If its any help, A=Cot(HA)Tan(Lat) B=cosec(HA)Tan(dec) and C=Cot(Az)Sec(lat)

    If there is any interest, I can scan the 'high latitude' portions and post them on the list.

    Regards
    Brad
    ----------------------------------------------------------------
    NavList message boards and member settings: www.fer3.com/NavList
    Members may optionally receive posts by email.
    To cancel email delivery, send a message to NoMail[at]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