Not long ago, a book editor was telling me how he'd been encouraging writers to start planning ''millennium novels'' sweeping fictions keyed to the past 10 centuries and timed for publication in the year 2000. I remember saying such books would be too sweeping, too chock-full of stuff, to be any good. Well, I take that back. Jumping the gun by seven years, Steve Erickson (Rubicon Beach, Tours of the Black Clock) has just published Arc d'X, the first bona fide millennium novel, and it's not just good, it's flat-out amazing: an allegory about the nature of freedom, the varieties of slavery, and ''the collision of time and memory, called history.''
In mid-18th-century Virginia, a rebellious slave is burned alive, and the smoke of her cremation is breathed by a small boy named Thomas Jefferson. He grows up and invents ''a flawed thing'' called America, a nation dedicated to liberty, yet he is unwilling to liberate his own slave and mistress, Sally Hemings: ''It was the nature of American freedom that he was only free to take his pleasure in something he possessed, in the same way it would ultimately be the nature of America to define itself in terms of what was owned.''
In Paris on the eve of the French Revolution, Hemings imagines murdering Jefferson with a knife she has concealed in her glove. And one night she does. Or dreams that she does then wakes in Aeonopolis, a theocratic city-state sprawled between the sea and a volcano. Here, cryptic graffiti (''Sonic Men, Anonymous God,'' ''Pursuit of Happiness'') appear and disappear, neighborhoods have names like Ambivalence and Sorrow, and a man called Etcher discovers the Unexpurgated Volumes of Unconscious History (which contain an entry for ''Sally Hemings,'' a slave from a country he has never heard of).
Part historical melodrama and part detective story, part cyberpunk thriller (dizzying jumps take us to 1999 Berlin) and part science fiction (there's talk about a dark temporal star ''weighing 72,454 seconds'' that sits between the millennia, waiting to swallow history), Erickson's tour de force unfolds with pitiless logic, gleaming prose, and passionate sympathy. A