Celestial navigation

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Now when she goes up Fifth Avenue-as she did with me that summer day-she addresses Fifth Avenue as the axis of the trough of a syncline. She knows what is underfoot. She is aware of the structure of the island. The structure of Manhattan is one of those paradoxes in spatial relations which give geologists especial delight and are about as intelligible to everyone else as punch lines delivered in Latin. There is a passage in the oeuvre of William F. Buckley, Jr., in which he remarks that no writer in the history of the world has ever successfully made clear to the layman the principles of celestial navigation. Then Buckley announces that celestial navigation is dead simple, and flexplek huren amsterdam that he will pause in the development of his present narrative to redress forever the failure of the literary class to elucidate this abecedarian technology. There and then-and with intrepid, awesome courage-he begins his explication; and before he is through, the oceans are in orbit, their barren shoals are b1ight with shipwrecked stars. With that preamble, I wish to announce that I am about to make perfectly clear how Fifth Avenue, which runs along the high middle of a loaf of rock that lies between two rivers, runs also up the center of the trough of a syncline. When rock is compressed and folded, the folds are anticlines and synclines. They are much like the components of the letter S. Roll an S forward on its nose and you have to the left a syncline and to the right an anticline. Each is a part of the other. Such configurations in rock compose the flexplek huren eindhoven structure of a region, but will not necessarily shape the surface of the land. Erosion is the principal agent that shapes the surface of the land; and erosion-particularly when it packs the violence of a moving glacier-can cut through structure as it pleases. A carrot sliced the long way and set flat side up is composed of a synclinal fold. Manhattan, embarrassingly referred to as the Big Apple, might at least instructively be called the Big Carrot. River to river, erosion has worn down the sides, and given the island its superficial camber. Fifth Avenue, up on the high ground, is running up the center of a synclinal trough. On the upper West Side that afternoon, Anita drew her rock hammer and relieved Manhattan of some dolomite marble, which she took from an outcrop for its relevance to her research in conodonts. She found the marble “overcooked.” She said, “To get that ldnd of temperature, you have to go down thirty or forty thousand feet, or have molten rock nearby, or have a high thermal gradient, which can vary from place to place on earth by a factor of four. This marble is so cooked it is almost volatilized. This-you better believe-is hot rock.”

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