Wagner's Ring: Turning the Sky Round, by M. Owen Lee (Summit, $16.95); Reading Wagner: A Study in the History of Ideas, by L.J. Rather (Louisiana State University Press, $35). Just in time for the PBS's complete "Ring of the Nibelung" (which starts tomorrow and runs for four nights), the first of these two books offers a brisk account of the action in the four operas, entertaining and intelligent interpretation and a guide to further reading and listening. Rather's book is probably more for the confirmed Wagnerian, as it examines the composer's ideas, prejudices and philosophy, including chapters on "German and Jewish questions" and "the insurrection of woman."

Route 66: The Mother Road, Michael Wallis (St. Martin's, $29.95). Route 66: The name itself is the ultimate evocation of the American love affair with the automobile and the open road. Think of the associations -- "Get your kicks, on Route 66," from the song by Bobby Troup. And the television show featuring Tod and Buzz, the two young men who roamed the highway in a Corvette. Here, Michael Wallis gives a history and state-by-state tour of the highway that "winds more than 2,000 miles all the way from Chicago to L.A." The book also includes numerous "Route 66 Portraits," including one of Troup, whose wife contributed to the writing of the song (while they were driving west on the Pennsylvania Turnpike) with the question, "Why don't you write a song about Route 40?"

The Baseball Encyclopedia (Macmillan, $49.95). This eighth edition of baseball's bible, almost 3,000 pages long, comes for the first time with the endorsement of Major League Baseball as the sole official record of the game and its players. As usual, The Baseball Encyclopedia includes single-season and lifetime records for all the men who have ever played in the major leagues, a roster of managers (complete with won-lost records), a chronological listing of teams and their players, a listing of awards and records, and a listing of trades and free agencies since 1900. Of special note in this new edition is the inclusion for the first time of records (albeit still sadly incomplete) for more than 130 of the best players from the Negro Leagues.

Freedom, by Pete Seeger and Bob Reiser (Norton, $29.95). This is a history of the civil rights movement in words and pictures, but unlike other histories of the movement, it focuses on the songs that inspired the marchers and freedom riders. There are, of course, the familiar songs -- "We Shall Overcome," "Ain't Gonna Let Nobody Turn Me 'Round" -- as well as others less well known, such as "Ain't A-Scared of Your Jail" and "Oh Wallace." Interspersed with the narrative history are profiles of activists like Rosa Parks, whose refusal to move to the back of the bus sparked the Montgomery bus boycott.

Newton's Madness: Further Tales of Clinical Neurology, by Harold L. Klawans (Harper & Row, $17.95). The title of this essay collection by a professor of neurology and pharmacology has to do with the breakdowns Sir Isaac suffered twice in his life. Klawans connects the great man's symptoms, which included severe insomnia and delusions of persecution, with his alchemical experiments and particularly the mercury poisoning he likely suffered in performing them. Other pieces shed light on the pathological origin of the medieval dancing mania that gave us the tarantella, speculate on the cocaine habits of Sigmund Freud and Sherlock Holmes, and warn of possible neurologic complications after surgical reduction of the stomach to combat obesity.

Central Park: The Birth, Decline, and Renewal of a National Treasure, by Eugene Kinkead (Norton, $22.50). Although it is encrusted with additions -- a zoo, baseball diamonds, extra entrances -- which did not figure into the magnificent original design by Frederick Law Olmsted and Calvert Vaux, Central Park remains one of the most captivating urban parks in the world, not to mention a sanctuary from the stress and clamor of the surrounding city. This history portrays the great space from its days when a camel on loan from an onsite menagerie pulled a lawn-mower to the recent period of neglect and vandalism and on to the renovation-in-progress, which is marshalling a $150-million budget and the services of countless volunteers to restore the park to glory.

Mama Poc: An Ecologist's Account of the Extinction of a Species, by Anne LaBastille (Norton, $19.95). To borrow a line from Ford Madox Ford, this is the saddest story. In the early 1960s the author's nature tour-guiding took her to Guatemala's Lake Atitlan, where she sighted a bird she could not identify. Neighbors described it as a "funny duck that never flew and could stay under the water for half an hour." Eventually the species was pegged as the giant pied-billed grebe, endemic to the lake. The past tense is necessary because LaBastille's 24-year-long campaign to save the bird failed. The book's title is a moniker given her by local residents from their name for the now-extinct species.

Paul the Convert: The Apostolate and Apostasy of Saul the Pharisee, by Alan F. Segal (Yale University Press, $29.95). Jewish scholars have never, understandably, had much time for Saul, the fanatical Pharisee transformed by a blinding light on the Damascus road into the equally fanatical Paul, apostle to the gentiles and, some say, the real founder of Christianity. Alan Segal's new book challenges Jewish and Christian scholars alike to take a fresh look at this well-educated man, arguing not only that it is impossible to understand Paul's Christian writings without understanding first-century Judaism but that early Hellenistic Judaism is itself illuminated by Paul, since he was one of only two Pharisees to have left any personal writings at all.