BOOK REVIEW: FICTION : Mind-Bending Mysteries of Adolescence : THE WIVES OF BATH <i> by Susan Swan</i> , Alfred A. Knopf, $21, 231 pages

Though a pair of books hardly constitutes a full-fledged trend, the simultaneous appearance of two Canadian women writers whose fiction explores extremes of physical and emotional aberration seems more than mere coincidence. Toronto, until recently an oasis of conservatism, has suddenly become the setting of choice for some decidedly Gothic literature.

Barbara Gowdy, the author of “We So Seldom Look at Love,” a collection of unnerving short stories reviewed earlier, has supplied a quote for the jacket of Swan’s “Wives of Bath,” a novel in which the young narrator suffers from the aftereffects of polio aggravated by the sensation of being unwanted by her overworked physician father and her self-absorbed stepmother.

In 1963, when she’s an intellectually precocious but otherwise immature 14-year-old, her parents send her off to board at Bath Ladies’ College. Medieval, dank and chilly, the college is ideally suited for the bizarre tale Mary Beatrice Bradford has chosen to tell.

Introducing herself as “Mouse,” a nickname she prefers to Mary Beatrice, the narrator loses no time in presenting her alter ego, the twisted shoulder she calls Alice. Consisting largely of scatological repartee, Mouse’s conversations with Alice are reproduced here along with her letters to John F. Kennedy, whom she has chosen as her confidant.

Almost immediately, there’s testimony from a murder trial in which Mouse Bradford appears as a crucial figure, a matter not resolved until the last few pages of the book. We do know, however, that Mouse has filched one of their father’s scalpels and included it among her personal effects--the green tunics and purple underclothes that make up the uniform of this highly unusual school.

The uniform is by no means the most original feature of B.L.C. In addition to a three-foot tall handyman, there’ a tricycle-riding ghost who sails through the halls at unpredictable intervals.

Moments after her arrival, Mouse is further surprised by the sight of a boy shaving in the dormitory bathroom. He is apparently the gardener’s helper and the brother of Mouse’s roommate, an orphan named Pauline Sykes.

There’s a third roommate as well: Victoria Quinn, as kind as she is beautiful.

Pauline Sykes is a special student, on scholarship at Bath instead of in the home for problem girls from which the headmistress had retrieved her. Before that, Victoria whispers, Pauline and her brother Lewis had been living on the streets.

Pauline and Victoria both befriend Mouse, despite--or perhaps because--she’s younger and a self-declared misfit. It’s immediately obvious that Pauline’s problems have not ended with her transfer to Bath, a circumstance that provides virtually the entire plot.

Though the school provides the ideal hothouse environment for the bizarre happenings that follow, there is a singular lack of information about class work or teachers, and only a few passing references to the sports and social events that increase Mouse’s general misery.

Still, she keeps her spirits up, rebounding even after her adored father’s death, sustained by Pauline Sykes’s interest in her. Pauline is teaching Mouse to transform herself into a boy, and the course is arduous, consisting of masculinity tests devised by the instructor, a truly sadistic personality.

Pauline is an amazing piece of work, all right, a worshiper of King Kong who easily turns the impressionable Mouse into her willing, if not always able, disciple.

While the recounted escapades grow increasingly grisly, not even the ominous hints scattered liberally through the book prepare the reader for the horrific denouement, a flash finish demanding not only a suspension of disbelief but faith that every character in the novel, from the lowliest student to the loftiest administrator, would be equally and totally gullible. Blind, really.

There’s just one exception, introduced extremely late in the game--but by definition, the deus ex machina can never arrive on the scene until matters are totally out of control.

Offered as a serious examination of the mysterious forms of adolescent sexuality, “The Wives of Bath” never approaches that target. Instead, the author settles upon one mind-bending example of chronic pathology, hereby becoming part of a curious “trendlet” in new Canadian fiction, a preoccupation with aberrant behavior.