NOW A PENGUIN MODERN CLASSIC: In this celebrated novel, Margaret Laurence writes with grace, power, and deep compassion about Rachel Cameron, a woman struggling to come to terms with love, with death, with herself and her world.      Living alone with only her aging mother for company, thirty-something retiring schoolteacher Rachel Cameron feels trapped in a milieu of deceit and pettiness--her own and that of others. She longs for love and contact with another human being who