By George Bowering

Viking. 266 pp. $16.95

"Caprice," by Canadian writer George Bowering, is the story of a poet turned fury, a woman who "rides a black horse west along the river valley, alone." The book jacket copy bills this novel as a takeoff of the standard western, but its roots are in an earlier literary form. Its protagonist, an amazon, is a classic dime-novel heroine.

Caprice stands more than six feet tall in boots, and she has deadly skill with a bullwhip. Like Hurricane Nell and the dime-novel version of Calamity Jane, she is sublimely beautiful and uses no last name. And like many of her earlier sisters, she left a life of culture -- the book of poems she wrote while living in Paris won critical acclaim -- to ride the range and avenge the murder of a loved one. Bowering uses cliche' in order to comment on it, and he invests this 19th-century form with modern-day sensibilities. The result is often funny and sometimes wise. Where the book fails -- and ultimately it does -- is in the author's self-conscious presence throughout the tale.

Bowering takes as his theme the invention of the West, the interplay between the myth created by pulp fiction writers, journalists and photographers, and the actions of Westerners themselves. "That was an awful irony for the western person," Bowering writes, "{who} could not help seeing that the West was every day becoming recognizably the past. It was slipping from the land into the landscape of stories about the West. It was becoming a style in eastern theaters and those theaters were beginning to show up in the West, and the West was now on the stage and in books and in songs instead of out the front door."

This theme has been popular with students of the West since Henry Nash Smith's landmark 1950 study, "Virgin Land: The American West as Symbol and Myth," but in "Caprice" the act of observing not only affects those under observation, but turns them into observers themselves, a process that ultimately destroys the West that shaped them.

Archie Minjus is a photographer who calls his photographs "shadows that speak from dying lips," and knows that "his lot in life was to invent the West as it disappeared into the past." A. Kesselring, a journalist, tells a villain, "My principal responsibility is to the story and its reader ... If you were a brown hat now, I would be serving the story well if I gave you a black hat." Caprice looks at a photograph of herself and thinks "it looked like an invention." And her lover -- schoolteacher and professional baseball player Roy Smith -- proposes marriage "for the future of the West."

These characters, as conversant with Goethe, Marlowe and Shakespeare as with the pulp authors, speak lines straight out of a humanities conference titled "Inventing the West." It's an intriguing notion but one that can be easily abused. Bowering's characters repeat their insights, only slightly revised, several times apiece.

And while the author hashes through the issues of Western Americana with an increasing tedium, he misses several important points. Like the dime novel authors he lampoons, he gives a woman a horse and a weapon but deprives her of deeper institutional power. Caprice has no money of her own but lives on drafts from her former husband in Europe. And although she can ride from Arizona to British Columbia alone and humiliate a sniveling blackguard with her bullwhip, when she is engaged in mortal combat -- as she is twice -- someone else steps in to save her.

More importantly, Bowering chooses an amazon as protagonist but sidesteps the essential question about her role in Western myth. Why, when the superhuman heroes of pulp fiction have done so much to shape the popular idea of what a man should be, have the heroines from the same genre done so little to shape what we believe a woman should be?

But for all these criticisms, "Caprice" has much to recommend it. The characters -- when they step down from their podiums -- are quirky and warm. The love scenes are drawn with a light but highly sensual hand. The first Indian and second Indian, a mentor-student pair cast in the role of Greek chorus, comment on the action with true insight and a welcome lack of pedantry. The book is rich with small but telling details about the West, such as the story of a woman who won a husband when, out of loneliness, she cast her poems across the prairie, attached to tumbleweeds.

Bowering also uses irony well when he trusts his reader to understand it without explanation. An Indian boy, who works at his lessons while Caprice and Roy Smith argue over marriage, stands up and holds out his pencil. "This thing," says the boy, "does not understand my words." It's a lovely interchange, a comment not only on the argument that preceded it but on the agony Roy Smith feels in trying to teach farming and literacy to a people most feel should "die and leave the new lands to the energy of a superior race."

Of course, the Indian boy's words may well be a comment on reviewers. This one, at least, was sad to see the marriage of a grand idea and an admirable talent fail under the weight of too much wit, too much wisdom and too much irony.

The reviewer, author of "Cowgirls: Women of the American West," lives in Portland, Ore.