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: The Nautical Day
    From: George Huxtable
    Date: 2004 Feb 8, 11:02 +0000

    I would like to thank Herbert Prinz for a well-argued reply to my question
    about the choice of time-argument in the early Nautical Almanac.
    Trevor Kenchington wrote, with other interesting comments-
    >I do have Greenhill & Hackman's "Herzogin Cecilie" (1991), which
    >includes some quotations from that ship's logbook in the hours leading
    >up to her stranding in 1936. Those clearly used the civil day (changing
    >24 to 25 April at midnight). Thus, I would tend to agree with George's
    >scepticism. Before withdrawing any suggestion of such a late use of the
    >nautical day, however, I would note that the same logbook says that they
    >"Changed the ship's time to land time at 2100 hours" of the day that
    >they arrived off Falmouth for orders. Most likely, that was either a
    >matter of correcting their reckoning for small accumulated errors in
    >their chronometer time or perhaps an adjustment of the watch schedule to
    >match GMT rather than local apparent time. However, it remains possible
    >from this limited evidence that the ship had been using the nautical day
    >during her blue-water voyage from Australia and changed to the civil day
    >on arriving in coastal waters.
    It seems likely likely to me that the phrase "Changed ship's time to land
    time at 2100 hours" really did imply that they changed from a noon-to-noon
    reckoning on the log to using midnight-to-midnight civil time. But what
    causes Trevor to think that the noon-to-noon reckoning could have been by
    the Nautical Day, 12 hours ahead of the Civil Day, rather than by the
    Astronomical Day, 12 hours behind the Civil Day? That's what I am trying to
    establish; the era in which Nautical Time finally fell out of use.
    contact George Huxtable by email at george@huxtable.u-net.com, by phone at
    01865 820222 (from outside UK, +44 1865 820222), or by mail at 1 Sandy
    Lane, Southmoor, Abingdon, Oxon OX13 5HX, UK.

    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