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    Re: The Dunlap Sunrise Sunset Computer
    From: Stan K
    Date: 2017 Sep 19, 23:05 -0400

    I have the 12th (1969), 13th (1978), and 14th (1985) editions of Dutton's.  FYI, the Dunlap Sunrise Sunset Computer made it into the 13th but not into the 14th.


    -----Original Message-----
    From: Brad Morris <NoReply_Morris@fer3.com>
    To: slk1000 <slk1000@aol.com>
    Sent: Tue, Sep 19, 2017 6:20 pm
    Subject: [NavList] The Dunlap Sunrise Sunset Computer

    As some may have observed, I will recommend Dutton's Navigation & Piloting to anyone wishing to learn celestial navigation.

    It has been and will remain my touch stone.  When the chips were down and the chips were counted, the US Navy practiced CN in the method proscribed in Duttons. The 12th edition was produced immediately before GPS navigation. It was the textbook used at the US Naval Academy for celestial navigation to train officers.  Practicing CN the Navy way will not lead you astray!

    My copy of Dutton's goes through the process of determining sunrise and sunset using the Nautical Almanac, but then offers a picture of a slide rule that does the same thing, that being the Dunlap Sunrise Sunset Computer.  For much more than a decade, I have searched for this slide rule.  It was simply not available.  

    One recently popped up, and I immediately purchased it.  After a bit of investigation, I am now ready to share it with the group.  Attached, please find a descriptive article.


    PS Dutton's has also directly influenced my support of the 2102D.  Further, it has directly influenced my support of HO229.  The use of these tools may not be the preferred method.  Much has been written about the supposed defects of the 2102D and the inadequacies of HO229. I beg to disagree with those assertions. My CN textbook of choice dictates these tools in equisite detail, providing cogent examples.  Who am I to disagree with the US Navy?  

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