Canadian Shields, whose The Stone Diaries (see below), is being released simultaneously with this short pair of midlife- crisis novels, has become prolific and good enough to earn comparison with Margaret Atwood. Here, the story of a marriage is told in two back-to-back novels, one from the husband's view, the other from the wife's. Jack and Brenda Bowman, 40-somethings who live in the Chicago suburbs, have braided lives, but, in her narrative, Brenda leaves Jack and her two kids to attend a convention for a week with her handmade quilts. The Brenda of old used to be ``smiling and matter- of-fact,'' but now she has ``a restless anger and a sense of undelivered messages.'' Things go wrong fast--dizziness, for starters--and after an affair with an engineer and some sitcom, she returns home and feels, for a moment, ``the Brenda of old,'' ``a self that is curiously, childishly brave.'' Meanwhile, Jack, a historian who believes that ``men spend whole lifetimes preparing answers to certain questions that will never be asked of them,'' deals with the kids, helps old friend Bernie (whose wife leaves him), visits a friend who attempted suicide, and finds that ``the void left by his shattered faith had inexplicably grown.'' Picking up Brenda, he feels ``a sudden buckling of his heart, for already he was sealing this moment in the clean preserving gel of history.'' The idea is a bit gimmicky, but the stories play out well. They're not the equal of The Stone Diaries; still, the husband and wife, baptized by brief separation, meet, literally, in the middle of the book, and that sensation--of matching the physical object of the book to the story--is worth the price of admission.