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Re: Places where Slocum mentions navigation-related items

From: Frank Reed (no email)
Date: Tue Dec 23 2003 - 16:47:05 EST

  • Next message: Frank Reed: "Re: The voyage of the CWM"

    Jan Kalivoda, you wrote:
    "Frank, from one your answer to Fred, one can assume:
    - the scarcity of Slocum's remarks about noon observations is the proof that
    such observations were so common for him that he didn't pay attention to them
    in his narration
    - the scarcity of Slocum's remarks about lunars is the proof that he didn't
    use lunars in other times than he mentioned it explicitly
    Am I right in following your argumentation?"

    In an over-simplified way, of course, that's right. But what of it? Fred's
    count of noon sun sights is what is commonly refered to as a "straw man"
    argument. It's a distraction. There is not the slightest doubt that Slocum got his
    latitude by Noon Sun sights each and every day that the Sun was visible.
    Shooting the Sun for latitude was a commonplace for a couple of centuries before the
    voyage of the Spray and for decades after it, and everyone knew that at the
    time and knows it today. Counting up Noon Sun sights is pointless. For another
    analogy, how often does Slocum mention ordinary waves? Not all that often. How
    often does he mention a rogue wave? Once. Can you reach any conclusion about
    the number of rogue waves he saw based on the number of ordinary waves he
    describes in the book? Could you multiply the number of ordinary wave references up
    by some factor and then conclude that he probably saw dozens of rogue waves?
    Of course not. He saw one, and he mentioned it because it was extraordinary.
    The scarcity of references to ordinary waves doesn't help us estimate the
    number of rogue waves.

    Similarly, navigating by lunars was an extremely rare activity in the late
    1890s --one that would merit mention precisely because it such a unique activity
    (and Slocum waxes poetic about it on that one day precisely because it was a
    nearly forgotten practice at that point in time). Did Slocum shoot lunars on
    one afternoon in the western Pacific?? Yes indeed. He says so. Did he shoot any
    others?? Maybe he did. Maybe he didn't. Slocum states very clearly in his own
    words that he found his "longitude, at least, mostly by intuition". He did
    not shoot lunars on anything like a regular basis. If there is evidence for a
    more regular and systematic use of lunars on the voyage, where is it? Slocum
    describes dead reckoning techniques in several places, but there is no further
    mention of lunars in SAATW beyond that one afternoon in the western Pacific.
    There may be other sources though: newspaper accounts of his voyage, descriptions
    of his logbook if not the logbook itself, contemporary accounts of the voyage
    in the navigation literature. I would love to hear of them --really.

    Frank E. Reed
    [X] Mystic, Connecticut
    [ ] Chicago, Illinois


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