NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: A poor read.
From: Herbert Prinz
Date: 2005 Apr 24, 09:22 -0400
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 depth? 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 continues "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