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: The Plane Scale and Stereographic Projection in Early Navigation
    From: Robin Stuart
    Date: 2024 May 29, 09:56 -0700


    That you very much for the earlier Aspley reference. I will amend the text and references accordingly.

    On the thread of the Dutch connection: van Poelje (https://eeuwen.home.xs4all.nl/images/Pics/Kombuispraat/Pleinschaal/200404 Gunter Rules in Navigation V13-1.pdf) states

    Aspley only gives a picture of the front side, but in reference [16] the Dutch expert on the history of navigation, Ernst Crone, supplies a picture of front and back of the Plain-Scale. This more complete picture has been found in a Dutch handbook for navigators [8] which addresses the same subject as Aspley’s book, though without any reference to him.

    In Figure 10 entitled "Aspley's Plain Scale" he shows a drawing of both the front and back sides. I have attached it here. However the scales from the back side don't appear to be consistent with the description that Aspley gives and that I quote in full in the paper. In particular one of the scales appears to be logarithmic.

    Robin Stuart


    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