THIS ENCHANTING historical novel, which begins with the crack of a whip in a Victorian buggy and ends with an apocalyptic dogfight in a World War I biplane, is a novel about aviation. It is almost a novel about opera, indeed the most sumptuous one ever attempted, with full-blown portraits of luminaries such as Caruso and Puccini as well as detailed expositions of operas and vocal techniques. As MacDonald Harris perceives them, flying and singing are intimately related related arts: both represent an ultimate performance, an exultant soaring above the ordinary.

Although Harris, a National Book Award Nominee, is mainly known as an elegant parodist of genre novels (The Balloonist, The Treasure of Sainte Foy ), here he is trying for something considerably more ambitious and serious. "No more parodies," he reportedly told his publisher. Nevertheless, Herma is at least, as Nabokov once said of his own work, on "the brink of parody": the heroine, an unknown soprano who conquers the Belle Epoque opera world, is named Herma; the hero, an aviation enthusiast who is her agent and her hermaphroditic other self, is named Fred Hite; their sexual and professional exploits are laced with all manner of erudite jokes and allusions, including Herma's losing her virginity in a theater to a movie projectionist named Earl Koenig during a film of Gotterdammerung .

What makes Herma a significant and delightful breakthrough for Harris is not, happily, a renunciation of spoofery, but a new range of technique and feeling. The writing in The Treasure of Sainte Foy , Harris' previous novel, was spare and clipped; here it is rich and expansive. As the irrespressible Herma rises from the obscurity of a small-town Baptist choir to the international opera stage, we are treated to lyrical, exacting descriptions of the Edison phonograph (with its "horn like a large flower"), the intricacies of flying, the chaotic dazzle of turn-of-the-century San Francisco, the opulent Paris of Marcel Proust, and the grotesque marvels of hermaphroditic transformation.

The most memorable and moving piece of purely descriptive writing is found in the ghostly aftermath of the San Francisco earthquake of 1906, rendered with the curiously formal outlines and poignant undertones so characteristic of Harris' style:

"A man wandered around asking everybody where he could get a shave. He had gone to his hotel, he said, and to his surprise it wasn't there anymore. A little farther on there was a small fire in a restaurant and the waiters were using soda siphons to put it out. . . . This seemed a purely formal procedure, a gesture of exorcism. . . . There were two levels of events in that four days of wandering about the city, the real and the fabulous. She clearly remembered, for example, seeing a lion and a pair of leopards slinking through the ruins of the Grand Hotel, although someone told her later that there was no zoo in San Francisco. More real, even though more ghostlike . . . was the well-dressed woman who sat in a cable car on Powell Street waiting for it to start, regardless that the pavement around it was twisted into waves like those of the sea."

The earthquake itself is first perceived by Herma as a dramatic rumble of tympani punctuating the precise moment Caruso finally succeeds in teaching her the "little lingering catch in the voice" that fuses technique with feeling and creates art. Indeed, the most dizzying technical feat in Herma is Harris' conversion of action into music, both through metaphors and through the form of the novel: when Fred, badly wounded from a flying accident, sinks into a featherbed with a voluptuous courtesan, he is "swept into a Wagnerian sort of ectasy in which pain mingled with the most intense of pleasures"; when Herma trades marvelously obscene sexual notes with Fred, her elusive male other-self, the complex "conversation" is rendered as counterpoint.

Harris rarely stays in one key. After the youthful discovery that opera, like aviation, is exactly analagous to the "vast richness and profusion of life," Herma and Fred encounter death, "a sudden cold clutch," and the correspondences between art and life ominously regroup: "At the opera, Death was only a song, a shift to the minor mode, a catch in the voice. In the air, hurtling through the sky in a fragile and fallible machine, it was a sharp reality -- something concrete and hard -- iron and aluminum, sharp edges, deadly weights that could sever and crush the flesh that had set them in motion."

As the flying scenes become more perilous and move into "frightening spaces where no one had even been and no one could think about," the musical harmonies subtly shift as well, from the extravagant sentimentality of Verdi to the austerity of the late Beethoven quartets, the latter brilliantly described in a culminating chamber music scene at the home of a "cadaverlike" Marcel Proust: c

"The harmonies were not quite right. Yet the correct harmonies were implied, behind the notes. The music said: you see, this is the way the harmonies ought to be. But they are not. The universe is awry. Herma turned to look at Marcel. . . . He was as intent and calm as though watching the execution of an enemy, or the slow wilting and decay of a flower."

From here it is a hauntingly logical step to the mysterious and strangely satisfying ending, in which things are left literally up in the air.

Despite its deathlike ending, this is not a depressing novel, any more than the late Beethoven is depressing music. On the contrary, Herma is an exhilarating work, surely one of the brightest of the season, by a superb craftsman working at the peak of his form. The shadow of mortality that spreads out at the end lurks implicitly from the beginning, a necessary counterpoint to the novel's vibrant and magical affirmation of life.