An intriguing departure for Jessica Stirling, writing as Crosby, from her chronicles of struggle and bootstrap triumphs in 19th-century Glasgow and from the richly peopled courtroom period drama (Lantern for the Dark, 1992): here, in a 1920's tale set mainly in a girls' boarding school in Scotland, an insecure and lonely 15-year-old girl finds direction and a kind of security. Pretty, flirty Barbara, Pauline's mother, took off with a lover when Pauline was eight, leaving her with her adored father, Harry. Life in London is good, then, until Barbara's own father- -fierce old Grandfather Haldane--forces Harry to take a job in South Africa and sends Pauline to St. Austin's, the ``family'' boarding school in Scotland. In the meantime, Barbara's lover has died, and she is now pregnant by--and awaiting marriage to-- unpleasant Mark Straker. Pauline's misery will lift at the school, where there are friends, although her horrid cousin Stella-- acidulous, sexy, mean as a hornet--is also there. At Christmastime, Pauline spends the holiday with the Haldanes in their handsome country home, a time of both jollity, with male cousins and a rough but kindly uncle, and nervous recognitions: of Barbara's unhappiness, Mark's callousness, and Stella's predation. It is on the trip back to school with Stella that Pauline gains the upper hand--to embrace a sister the family shunned--with the result that she can return to school ``safer than she had ever been.'' A leisurely period novel, in tune with its times and upper- caste juvenilia--but the long outdated British slang and mores will undoubtedly deter American teens who might be attracted by Pauline's dilemma. Before its delicately poignant coda, the novel offers some tangy talk, a great house-hunt, and school banter. It's all there, ``old son,'' for anyone yearning for an Anglophilic bash.