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    Re: Ogura IJN
    From: David C
    Date: 2017 Aug 9, 13:36 -0700

    Greg wrote

    You might want to give a slide rule a try for solving azimuth. I like slide rules that have the S scale just above the C scale on the slide (see Post Versalog 1460). First solve for prime vertical

    I am of a generation who was provided with a slide rule when starting work. I still have it. Several months ago I got it out and tried working a sight. I had four problems:

    • The trig scales are decimal degrees.
    • My aging eyes found reading the scales difficult.
    • The slider is sticky. Following instructions I purchased some vaseline but that did not solve the problem.
    • I had forgotton how to use it.

    I  also decided to make a flat Bygrave. Unfortunately my local stationary shop had just rearranged its stock and I could not find any projector film.

    In the meantime I am happily working sights by short methods.

    The great thing about astro is it has many facets. When I reach a road block with short methods (or get fed up) I can switch to something else (-;

    Tio change the subject slightly - given that the Hydrographic Office had an excellent (in my opinion) set of tables in Dreisonstok why did they put resources into a competing set of tables (Ageton)?

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