NICOLE BROSSARD has structured her ninth novel, Mauve Desert (Coach House, 176 pages, $14.95 paper), translated by Susanne de Lotbiniere-Harwood, as a triptych that folds in on itself In an intricate tale of place, quest, seduction, mystery, and murder, she has "let seep out like an unobstructed story, a part of her self, the undivided part." The three divi sions of the novel are 15-year-old Melanie`s journal, an erotic/philosophic confessional itself entitled Mauve Desert, actually spilled out by Laure Angstelle; the possession by this chronicle of Maude Laures, who takes on Angstelle`s book "body -to-body"; and Laures`s translation of Angstelle/Melanie`s Write of passage through the ardent but inevitably selec tive eye of her own sensibility. Keep in mind that we, in fact, are reading an English translation of Brossard`s own work, and mirrors proliferate between writing, reading, and the innermost and outward enactments of language. Erosion as perpetrated by light figures (or disfigures) prominently within Brossard`s incessantly shifting metaphors. We are frequently enriched by her gambles; at times, however, her philosophical abstractions so dematerialize the real that we lose the necessary obstruction and grounding of objects` provident solidity. Characters do not always sound true to their spirit; even when illiterate (Lorna in this novel) they speak "Brossard." Avowedly "inverse," Brossard praises the "isolated realities" of word, around which spins our common, fictive world. Mauve Desert glitters as one of these rarefied reals, condensed from the genetics of language recoded. As for the murder in the text, whodunit if not the author, shooting from the raw edge of risk where the revolver (surely always the word, on which her worlds turn, shimmer, and explode) "is always loaded."