THE 300th and 400th anniversaries of Christopher Columbus's landfall in the Americas celebrated the man and his "discovery." If this year's quincentenary books are any indication, 1992 celebrations will be more sober.A strong revisionist current runs through many of these books. Columbus did not "discover millions of Native Americans knew where they were and what they were about. Rather, he "encountered," and that encounter was at great cost to indigenous peoples, argues Zvi Dor-Ner in Columbus and the Age of Discovery (William Morrow, 370 pp., $40). The publishers of this companion book to a PBS television series describe it as the "definitive book" to emerge from the Columbus quincentenary. It may well be. The rang e of maps and the quality of scientific explanation alone reward close reading. While special interest is accorded native peoples who disappeared forever as a result of their meeting with Columbus's ships - the Tainos, Arawaks, Caribs - this book steers clear of moral judgments. Its goal, the author explains, is simply to provide "many voices" in the "encounter" of cultures. John Dyson's Columbus: For Gold, God, and Glory (Simon & Schuster, 228 pp., $35) offers another in a long series of Columbus conspiracy theories. Dyson and consultant Luis Coin document what they say are nautical discrepancies in Columbus's account of his first voyage: "absurd" bird sightings (pelicans and ducks in mid-ocean), contrary currents where they should not be. Columbus, they conclude, seemed to know where he was going, likely had a secret map, and manipulated his journal to disguise that fact. His goal was not to find a new route to the Orient, but to hunt for gold. This secret-map theory is a variation of the better known "Nordic myth" that Columbus learned about Leif Ericsson's Vinland while on a trip to Iceland as a young man. The docudrama style of the Dyson account does not lend credibility to the new, and admittedly circumstantial, evidence he provides. "The rain tasted of salt as he [Columbus] stumbled out into the disheveled wilderness to heave on frozen ropes, the icy wind knifing through his fleecy sheepskin jerkin and woolen cap." One problem all biographers have grappled with is Columbus's claim to have been the first to sight land. At 10 p.m. on Oct. 11, Columbus reports seeing "a little wax candle bobbing up and down" in the distance. Dyson's account of the claim posits duplicity on all sides. "While standing on the poop he [Columbus] saw a light 'so uncertain a thing that he did not wish to declare it was land ... like a little wax candle lifting and falling.' His servant, who must have known on which side his bread was buttered, confirmed the sighting, but the royal comptroller did not. Nor did any of the sailors who were looking out so keenly. The only possible conclusion is that the captain-general's claim was a contemptible fabri cation." The Dor-Ner version avoids taking a position. "His vision of the tiny light had apparently been a real one, though from Santa Mars distance it is hard to imagine how he could have seen light on land." Contrast the shrill tone of the first and the evasive tone of the second with Samuel Eliot Morison's account in his 1942 classic, "Admiral of the Ocean Sea" (reviewed on Page 9): "I agree heartily with Admiral Murdock, 'the light was due to the imagination of Columbus, wrought up to a high pitch by the numerous signs of land encountered that day. The best we can say in extenuation is to point out that glory rather than greed prompted this act of injustice to a seaman; Columbus could not bear to think tha t anyone but himself sighted land first. That form of male vanity is by no means absent from the seafaring tribe today." Morison's account still provides the most exhaustive analysis of Columbus's journals and clues to Columbus's character. While other captains often erased records of navigating errors, Columbus let his mistakes stand and he was careful to log any accidents. To argue the contrary, Dyson needs a tighter analysis than provided here. Jeffrey Burton Russell's book, Inventing the Flat Earth: Columbus and Modern Historians (Praeger, 117 pp., $16.95), takes on another aspect of the Columbus myth: the "persistent illusion" that Columbus proved the earth was round "to the astonishment of his contemporaries, who believed that it was flat and that one might sail off the edge." The confrontation at Salamanca between the rationalist mariner and medieval clerics immortalized by Washington Irving's "History of the Life and Voyages of Christopher Columbus" (1828) was pure fabrication. Fifteenth-century astronomers, geographers, philosophers, and even theologians - the villain's of Irving's history - not only accepted the premise that the earth was round, but also wrote sophisticated treatises on it. Columbus, apparently misled by Marco Polo's erroneous estimate of the breadth of As ia, argued that the earth was only two-thirds its actual size and most of it was dry land. "Columbus's opponents, misinformed as they were, had more science and reason on their side than he did on his," Russell says. Leading biographies are in agreement on this point: Educated people in 1492 believed the earth to be round. The analytically interesting question, then, becomes why a myth to the contrary was perpetuated. Russell traces perpetuation of the "flat earth error" to "amiable progressives whose disdain for the Catholic Revival and the Romantics of the early 19th century colored the way they viewed the Middle Ages." The image of benighted clerics seeking to crush Columbus was a "convenient symbol" used as a wea pon against anti-Darwinists. In the United States, "by the 1870s the relationship between science and theology was beginning to be described in military metaphors," he writes. As intellectual history, this account is riveting. Russell's conclusions, however, turn polemical on their own terms. historians, who could be expected by the nature of their trade to understand that every worldview is a human construct and that paradigms of knowledge are precarious and inevitably change, including the religious, scientific realist, and positivist worldviews, sometimes forgot that there are and can be no privileged systems by which to judge the truth of other systems." The leap from the observation that conventional thinking is too readily convinced of the ignorance or stupidity of the Middle Ages to the claim that there are no legitimate value judgments to be made about the period is swift and broad in this book. It leads to curious and sweeping generalizations in the concluding pages: fallacies or 'myths' of this nature take on a life of their own, creating a dialectic with each other and eventually making a 'cycle of myths' reinforcing one another. For example, it has been shown that 'The Inquisition' never existed, but that fallacy, like the flat earth fallacy, is part of the 'cycle' that includes the Dark Ages, the Black Legend, the opposition of Christianity to science, and so on." Barnet Litvinoff's 1492: The Decline of Medievalism and the Rise of the Modern Age (Charles Scribner's Sons, 268 pp., $24.95) takes a far darker view of the Old World. There is no hesitation about value judgments in this shoot-from-the-hip, highly partisan romp through hundreds of years of history. the gathering of Catholic eminence into the soiled hands of Rodrigo Borgia just as Christendom's cultural springs were deprived of Lorenzo de' Medici added a particular poignancy to the year 1492. That this should occur precisely when Christopher Columbus sailed from Palos in Spain to take the continent to a virgin frontier suddenly made Europe appear simultaneously in a condition of decay yet renewal." As Columbus sailed through the Saltes on his first voyage, he passed the last boatload of Jews being evicted from Spain. The spirit of racial pride behind the Inquisition and the expulsion of the Jews would follow Columbus to the New World, where before its final abolition in 1820, some 32,000 heretics were consigned to the flames," Litvinoff writes. Seeds of Change, by Herman J. Viola and Carolyn Margolis, (Smithsonian Institution Press, 278 pp., $40), traces the encounter of New and Old Worlds in terms of value-free microbes and seeds and the vast cultural, environmental, and biological changes they set in motion. This careful book could have the longest shelf life of any of the quincentenary offerings. Finally, a gentle offering. Barry Lopez's The Rediscovery of North America (University Press of Kentucky, unpaged, $15) shares the revisionist characterization of the discovery as deeply stained. "This incursion, this harmful road into the 'New World' quickly became a ruthless, angry search for wealth. It set a tone in the Americas." Unlike other accounts, this book does not build to a shrill indictment. It concludes with something like a secular prayer: a call for "profound courtesy, unalloyed honesty, " a determination to transcend "corruption" of the past and "mean something else in the world."