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: Why is a sextant like it is?
    From: Alexandre Eremenko
    Date: 2004 Nov 18, 14:51 -0500

    Dear Jared,
    On Thu, 18 Nov 2004, Jared Sherman wrote:
    >  for measuring angles?>
    > Ergh, because a mile is a minute?
    I am sorry, but is seems that "the mile is a minute"
    is the DEFINITION of the (n)mile, which was made
    just because people wanted to preserve this super-ancient
    system of degrees and minutes. The nautical mile was introduced....
    I don't know exactly when, but centuries if not millenia
    after this Babylonian hexadecimal system.
    (Let Herbert Prinz correct me here. I really don't know much
    about history).
    > Or it converts
    > nicely
    > to radians for
    > spherical trig?
    Well, nothing converts nicely into radians:-(
    That's in the essence of the things.
    That's how God created the world, with this transcendental
    number pi=3.14159265358... ... :-)
    Probably He did not want it to be too simple...
    Or wanted to give jobs to mathematicians... Who knows.
    And I understand that those "Haldeans" in Babylon (Irak?) were clever
    guys, and this hexadecimal system has some justification.
    (60 is divisible by 2,3,4,5,6,10,12,15,20 and 30)
    so it is a unique number in some sense:-)
    And I understand that base 10 is completely arbitrary
    (justified only by number of fingers on our hands)
    and that choosing the base to be 8 or 12 would be more reasonable...
    But still...for 1000 years at least we are all trained
    to use decimal system.
    (I was actually surprised, and... so to say...
    was moved (or touched) by the chapter in Norie (1828)
    on "Decimal arithmetic".
    But we still measure time and angles by that (super)-ancient
    P.S. I said super-ancient, because "ancient"
    is what we usually call Greeks. (More precisely,
    "Alexandrian" or Ellinistic scientists III-II B.C.
    who apparently "invented" science and math (in the
    modern "Western" meaning of these words).
    For those Ellinistic scientists,
    Babylonians were already "antiquity". That's why
    I add "super".

    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