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    Re: A poor read.
    From: Herbert Prinz
    Date: 2005 Apr 24, 09:22 -0400

    George Huxtable expressed his dislike of
    >"My old man and the sea", by David and Daniel Hays (Headline
    >publishing, 1995).
    When I got my copy, I was skeptical after seeing the endorsement by
    William F. Buckley, Jr. on the dust jacket: "Will be read with delight
    100 years from now." As much as I tend to agree with Buckley's political
    opinions, he never was able to offer me much insight into the art of
    sailing (including his video on navigation). And just as Buckley's
    sailing stories are merely vehicles to transport his world view, I
    expected nothing different from a sailing book that he recommends.
    The English edition will probably have come in a different dust jacket.
    Still, George could have saved himself some disappointment had he taken
    the prologue literally, where David Hays explains "My son Dan writes of
    a voyage external and internal, a true passage of personal struggle and
    growth. To me, the account is a love story." But how could George have
    known what to expect, after the author goes on to claim "But always it
    is the story of sailing a small boat [...]". Well, simply put, it isn't.
    In this respect, the book is extremely meager.
    Psychoanalysts will probably find some very interesting study material
    in the story, if they care to wade through the boring parts bare of any
    interest whatsoever and can at the same time tolerate the tasteless,
    sophomoric "humor" and vulgar language in the passages written by Dan
    Hays. On the other hand, what William F. Buckley saw in the book, is
    beyond me. He might reveal it one day. Was it the joke about the rabbi
    that already tickled George's fancy, or the various delectable
    descriptions of urinating, or some other passages of equal philosophical
    George deplores the lack of details about navigation. I consider this
    restraint a blessing. The few elaborations on navigation that are
    present in the text are actually quite hair raising. Take for example
    the explanation of a sun sight. (p. 85 in the edition published by
    Algonquin Books of Chapel Hill, 1995.)
    To begin, David Hays remarks that "Some good sailors have written that
    they know of no simple text that combines theory and practice, but they
    must have missed Mary Blewitt's _Celestial Navigation for Yachtsmen_.
    [...] She has written the best text that I have ever seen on any
    subject." Let's see what Hays got out of this so highly commended text.
    He explains the process of finding one's position from a sun shot after
    having taken a sight of the sun and having found its GP from an almanac
    as follows:
    "Now you have two angles: the one you caught in your sight, and a right
    angle [...], because at the GP [,...] the sun is obviously straight up.
    And you know a distance - from the surface of the earth to the earth's
    center. As you remember from geometry, a triangle can be solved with two
    sides and an angle, or two angles and a side (distance),  and here you
    have that."
    In fact, what we really have here is a magna cum laude graduate from
    Harvard who has trouble understanding the most basic high school
    geometry and thus falls victim to a didactically questionable text. Hays
    "The side of the triangle you now want to find is the side lying on the
    surface of the earth between where you took your sight and the GP. That
    side is your distance from the GP [...]" Then he immediately refers to a
    diagram where the "explanation" is entirely different: In the diagram,
    two sides of the "triangle" are given, namely the distances from the
    center of the earth to the observer, the distance from the center of the
    earth to the GP, and the enclosed angle. From this, we can compute the
    distance from the observer to the GP.
    So, which is it? Do we compute the distance from two angles and one
    side, or from one angle and two sides? Of course, both variants are
    equally silly. We don't need to compute any distance from a triangle. We
    have just measured its complement. The only distance we are interested
    in, is our _angular_ distance from the sun.
    So far the combined wisdom of Mary Blewitt and David Hays. I would not
    have gone into so much detail if this were not a perfect example of how
    counterproductive the uncritical use of the flagpole paradigm, as
    introduced my Mary Blewitt, can be. I have called its proponents "flat
    earthers" because they replace the angular distance that we seek (by
    measuring it directly!!) with a linear distance that is computed from a
    fictitious right triangle. We must assume that Hays' misconception of
    having to solve a right triangle comes from Fig. 21 on p.19 in Blewitt's
    book. But there, the vigilant reader will see how the flagpole works on
    a flat earth and _only_ on a flat earth, while celestial navigation
    works _only_ on a curved earth. Blewitt (with the later help of Bergel)
    fooled many. Most list members are probably weary with my repeating this
    over and over again, but as long as I keep finding published texts of
    authors who evidently fell into this trap (and not just beginning
    students, as it is sometimes claimed) I will continue to point out that
    Blewitt's flag pole does more damage than good.
    Where Hays's navigation is concerned, it gets even more confused a
    little further down in his book, where we are told
    "[...] your GP may be thousands of miles away - too far to draw
    accurately on a chart. So you use basic geometry again and advance it
    toward you based on your time zone, establishing a nearby surrogate GP."
    I have never before heard about this curious method and should like to
    learn more about it. To be sure, Mary Blewitt did not teach him this
    trick. Should Hays have completely misunderstood what the "best text
    ever written on any subject" says in the chapter on "Spherical Triangles"?
    Finally, we read this sentence:
    "Of course, the surface of the earth is part of a sphere, not a circle,
    so spherical and not ordinary high-school geometry is used - but again
    the tables do that, not you."
    The last statement pretty much sums up the artist's approach to
    navigation: We deal with symbolic figures like circles, lines and right
    triangles. Although these are just metaphors for spheres, curved
    surfaces, etc., we don't need to worry about the details, because it all
    works like magic through the secret tables. I would not mind if a
    psycho-drama remained silent about navigation. But all the quoted
    statements are, in fact, made with the express intention to provide
    "[...] some theory in a few oversimplified paragraphs for those of you
    who wonder what that mariner is doing, squinting into that curious device."
    Since the Hays came home safely despite their navigation, God must love
    them. Unlike the rabbi in the joke, they told the story.
    Herbert Prinz

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