An E-Ticket Ride : A grotesque, futuristic world centers on a Disneyland run amok : THE UNUSUAL LIFE OF TRISTAN SMITH, <i> By Peter Carey (Alfred A. Knopf: $24; 432 pp.)</i>

If the 17th-Century Dutch hero, Admiral Tromp, had used a bigger broom--he attached it to his mast to signal that he was about to sweep the English from the seas--perhaps our world would have resembled the one set out in Peter Carey’s prickly futurist fantasy. In “The Unusual Life of Tristan Smith,” the era’s dominant military, economic and cultural empire resembles the United States in a number of ways, except that its heritage, like that of white South Africa, is not British but Dutch.

The empire is called Voorstand. It is a vast continental realm, run by a moneyed class that speaks a kind of Dutch-Afrikaans patois and pays lip service to a tradition of sturdy God-fearing settlers, while living in high-tech luxury and treating the slum-dwellers in its decaying capital as fourth-class citizens. It uses cash, guns and an intelligence service to protect its interests around the world.

A few of these interests--an underground naval-communications network and a nuclear-waste dump--reside in the fragile island nation of Efica, somewhere in the South Atlantic. The Eficans, descended from French and English settlers, are down-at-the-heel and, as Carey puts it, “laconic, belligerent and self-doubting.” Their capital, Chemin Rouge, is “a small, slightly rancid port city.”

Nonetheless, Efica possesses a scruffy human charm. Though the Voorstand version of the CIA works with the local intelligence service to keep the right-wing Reds party in power and sabotage the mildly radical and anti-Voorstand Blues, the place is too insignificant to have its local particularities obliterated. When the book begins, for instance, work has only just started on the country’s first Sirkus.

Sirkuses are Voorstand’s great cultural weapon, and Carey’s parodic equivalent of Disneyland. They are spectacular displays of holographic images coupled with real-life acrobatics that have the distinction of leaving the performers frequently dead or maimed. Like Disneyland, they have two trademark characters: Broder Mouse and Oncle Duck. It is worldwide junk-food entertainment: irresistible, and shriveling all merely local and particular cultural endeavors.

Tristan is born, hideously deformed, into one such endeavor. His mother, Felicity, runs the Feu Follet (Will o’ the Wisp) theater company, which tours the islands putting on avant-garde versions of the classics. The downfall of the company, Felicity’s subsequent fatal entry into politics as a Blue--she is murdered by Voorstand agents--Tristan’s injured youth, and his pilgrimage to Voorstand form the plot of Carey’s gaudy satirical exercise.

“The Unusual Life of Tristan Smith” is elaborate and parodically referential in strict and, in this case rather sterile, post-modern fashion. Tristan, crippled, lipless, dwarfish and with a raging need for love and justice, inevitably calls to mind “The Tin Drum’s” Oskar, rat-tat-tatting his way through a grotesque and unpredictable world.

Wearing a Broder Mouse mask as a child and the entire outfit while adventuring in Voorstand, he is used as other contemporary writers have used cartoon heroes: Jay Cantor with Krazy Kat, Frederic Tuten with the Belgian Tintin and Robert Coover with Pinocchio. Such use declares a malevolent impenetrability and unreality in modern life, so pervasive that only as a cartoon can heroism or even simple emotion be credible.

In fact, Carey, author of “Oscar and Lucinda” and “The Tax Inspector,” has written something of a hybrid. Tristan and the other characters go back and forth between human and cartoonish, particularly in the first part set in Efica. Here the book’s prevailing tone--an extravagant but flat hyper-reality--is tempered by moments of imaginative intimacy. Its structure, which toward the end is inhabited mostly by the games played in it, shows signs of human occupancy.

Felicity, beautiful, high-strung and combative, is an impressive figure, although more of a force, perhaps, than a person. Her two lovers, either of whom could be Tristan’s father, are more abstract; Carey has designed them but he has not really built them. One is Bill, an actor in the Feu Follet company, who emigrates to work in a Voorstand Sirkus. The other is Vincent, a wealthy businessman who launches the opposition campaign that will end up with Felicity hanged in her own theater.

Much livelier are Wally, the theater manager, who loves Felicity unsuccessfully and ends up taking care of Tristan and accompanying him to Voorstand, and Roxana. She arrives on the scene with cratefuls of pigeons; Wally, instantly besotted with her, buys them. It is a comic and ultimately melancholy courtship. Beautiful, ambitious and childlike, Roxana is also mad.

The madness--she is a pyromaniac and ends up trying to poison Tristan--is more than a sign of the times or metafictional gesturing. It is a human gap through which the endearing love that she and Wally eventually find for each other will sadly drain away. When it does, and she disappears, she takes with her the enticing quirkiness that Carey has managed to suggest for the Efican world. The book goes into hyper-real overdrive.

Tristan, now 22 but still only three feet tall, sails to Voorstand with Wally, who has grown old and cranky, and a nurse who goes under the name of Jacques. He (or perhaps she) is in fact someone else and, at the end, an unlikely hero/heroine.

The trek to Voorstand’s capital is full of difficult adventures; among others, the robbery at gunpoint of Tristan’s money, which he has earned playing the stock market via computer. There are encounters with spies from Voorstand and Efica who try to kill him, and with a robot Broder Mouse, which Jacques eviscerates so that Tristan can hide in it. As Mouse, he enjoys enormous success with Voorstand’s rich and powerful, particularly with a millionairess who provides him, despite some zipper trouble, with his first sexual experience. Finally, there is escape to freedom with Jacques and Bill, the father whom Tristan rediscovers. Their route leads across the Arctic Circle. Carey conveniently bends it, pretzel-like, so that Voorstand can be both polar and subtropical.

Some of these things are diverting and quite a few are clever. We can note their satirical lessons; the noting is rather detached, though. Tristan’s adventures in Voorstand have the approximate relation to human adventures that Warhol’s soup cans have to soup. Tristan, who back in Efica often was as real as soup--he suffered the extravagant pain of his young life and, more often than not, we felt it along with him--has turned into an airy cartoon. He leaves no pain behind.