ELIZABETH HAND is a brand-new name, and she has just published her first novel. It is big, and it is worth praising. Winterlong (Bantam, $4.95) is a dense, graceful, bullying book of great length and much skill; it is a live tale, told in a live voice, by an author of muscle and drive and ambition; its publication as a paperback original shows the depth of talent available in science fiction. But enough of being positive. A necessary downside of the ambitiousness that shows in every page of her romance is the fact that Winterlong is also messy, overextended, pompous, derivative and daft. Every silver lining has a cloud.

Hundreds or thousands of years have passed in America as the long tale opens, in a medical research establishment somewhere near Washington, D.C., a city whose familiar place names have been altered by long centuries of plague and catastrophe and political upheaval. No energy-consuming technologies have survived but genetic engineering has flourished; "geneslaves" roam the forests, and no one who lives on the surface of the world seems entirely sane or sapiens. Several Ascensions -- political revolutions seemingly directed by elite humans who live in orbit -- have succeeded one another, and each period of turmoil has left the world stranger than before. Rumors of a Final Ascension are now rife.

Wendy Wanders, an autistic orphan, has been medically transformed into a kind of vampire empath, a creature who can read the dreams of others, and steal them. (Her appalling moniker and the absence of any compelling rationale for her medical transformation are two signs of Hand's occasional lack of novelistic good sense.) After being read by Wendy, patients tend to commit suicide. Notwithstanding this, her mentor at the establishment asks to be read herself, and reveals a series of dreams in which her long-dead twin brother is psychically ingested by a godlike Boy, a Pan-figure, who calls himself Baal, the Gaping One, and Osiris, and so on. He also (Hand, one suspects, will live to rue this dreadful inspiration) calls himself Peter Pan. Wendy takes him into her psyche. Her mentor commits suicide. Enemy dirigibles bomb the establishment with a rain of roses, or plague. Wendy escapes.

Meanwhile, in the City, Wendy's own twin brother Raphael, who has been raised as a male courtesan, begins the first steps of his own long trek. He too contains within his psyche a potent ghost of the dreadful Baal Boy. On discovering that Wendy exists, Raphael finds he must seek out union with his sister, whose name, we soon learn, is also Magdalene, and Isis, and so forth. Clearly, by evoking the brother-sister god-pairs so central to pre-Christian religions, Hand hopes to make it clear that Winterlong is more than your usual sf novel; and just as clearly the tale is going to have to culminate in some sort of mythological Big Bang, presumably at the traditional Masque of Winterlong, held on the shortest day of the year, when the incestuous union of the heavenly twins will join Love and Death in celestial wedlock.

Unfortunately, Hand does not choose to move directly to this chosen climax, and Winterlong becomes, for hundreds of pages, little more than an anthology of the Dying Earth cliches of all the writers who have preceded her in this kind of story. But enough of carping. Hand has an extremely acute eye for psychological extremity; she hardly writes a bad sentence, and has in fact filled Winterlong with hundreds of fine ones. Winterlong goes part of the way, then stumbles, and becomes merely too long; but the effort is there, the joy of creation, the thrill of abundance. It was exciting to find her. Elizabeth Hand will be back. Limited Partners

IN ANY OTHER part of the world of letters but the land of sf, Gardner Dozois would have simply fallen silent. Always prone to dry spells, and in recent years fully occupied with editing Isaac Asimov's Science Fiction Magazine, he has never been a man to publish a book a year, or to flood the journals with stories. In the late 1970s, he began to suffer from a writing drought that looked as though it might become permanent. But because he was an sf writer, and because sf writers have always collaborated with one another more than writers of any other kind of literature, he turned to his friends. The stories in Slow Dancing Through Time (Ursus, $22) are the result.

They are, of course, collaborations. Some of them are triple collaborations. The authors involved, with the exception of Susan Casper, are widely known in the field. Jack Dann and Michael Swanwick, like Dozois, have published books whose individual voices are unmistakable; and Jack C. Haldeman II, obscured for years by Joe Haldeman, his active younger brother, has slowly become identifiable as a figure in his own right. In a series of forewords and interjections, all five speak of the pleasure and sense of mutual security they derive from co-authoring stories; they speak of the joys of workshopping, the conviviality, the gossip -- and the money, because most of the work here published was old first to high-paying magazines. And it is certainly the case that the stories collected in Slow Dancing Through Time are crafty and competent and knowing.

But that is not all they are. They are also indistinguishable. When they tug at the heart-strings -- "Touring," for instance, which joins Buddy Holly, Janis Joplin and Elvis Presley in a posthumous gig -- they do so with the Dynaflow efficiency of the most advanced chess computer. Horror -- "The Clowns" is grim and gripping and icy -- is similarly honed to an impersonal accuracy. And occasionally, as in "Time Bride," which is about a man who spies through time upon a young girl and destroys her life through his intolerable snooping, there is a stain of moral obtuseness, as though the technical joy of constructing the artifact of story had blinded the authors to its human dimension. All in all, Slow Dancing is a rather frightening book. It reduces the possibilities inherent in the genre to a calculus of effect, rather arousing to experience, and rather desolate. But the gang had fun. Growing Up Is Hard to Do

MICHAEL KANDEL, two of whose translations of Stanislaw Lem have been nominated for the National Book Award, has begun to write tales on his own. In Between Dragons (Bantam, $3.95) is the second of them. It is an extremely odd little book. If Lem himself had written a juvenile and had been capable of setting it in suburban America, then something like In Between Dragons might have been the outcome; for there can be no denying Kandel's debt to Lem's abrasive way with conventions, or to his intense ferocity. As with Lem's work, In Between Dragons makes more sense as an engine of interrogation.

What is being interrogated in this case, most amusingly, is the ethical nature of the fantasy worlds modern young Americans have available to them through books, role-playing games, television.

Pimply, awkward, tongue-tied Sherman Potts has discovered in himself the ability to flicker out of the mundane world into a series of magic kingdoms, where he has adventures featuring lots of action and harmless machismo. But puberty is assailing him back on Earth, and his escapades begin to darken, to become morally dubious, impossible to keep simple. Life, with its terrible incapacity to keep to the storyline, has seeped into the furthest recesses of Sherman's dream-world, and somehow he must extricate himself from the ocean of story, without doing fatal harm to the fantasy companions of his childhood. He must grow up.

Just as in the Jonathan Carroll novels that In Between Dragons also resembles, this process will cost dear. But Carroll never allows his characters to take much pleasure in the realities for which they eventually opt. It is a measure of the sharpness and complexity of this short book that we both regret the lost land of Sherman's youth, and welcome, guardedly, the real world to come. Dangerous Visions

IT HAS ALWAYS been the case that the best character Harlan Ellison ever created was Harlan Ellison, and that some of his weaker stories fell apart because they could not contain the rasping voice of their creator. The Harlan Ellison Hornbook (Penzler, $22.95), because it is all about the best character Harlan Ellison ever created, avoids the problem. These autobiographical essays, most of them originally published in the Los Angeles Free Press in 1972-73, are magically relaxed in comparison to much of his fiction, colloquial, superbly easy to read. Ellison himself, gullible and generous, or intoxicated with rage, burns into the reader's mind, utterly believable, absolutely open to the world. He makes terrible mistakes about lovers and fellow writers, and tells us all. He threatens and cajoles and boasts, and we listen. We want to tell him we do love him. We want to shake him till his teeth rattle. We want him to shut up. But most of all we want him to continue.

John Clute writes frequently about contemporary fiction. His most recent book is a collection of essays, "Strokes."