According to Denmark’s great Romantic choreographer August Bournonville (1805-1879), the idea of home is a splendid subject for a ballet because it raises the question of self-identity — a profound and eternally fascinating theme that is a staple of art. The most affecting of Bournonville’s works and a linchpin of the Royal Danish Ballet’s repertoire, “A Folk Tale,” created in 1854, explores the fate of a pair of infant girls who have been surreptitiously switched in their cradles. One is an heiress of genteel birth, the other a member of the troll clan that lives under Scandinavia’s hills, emerging at intervals to do mischief to the human society it envies and loathes. Each of the changelings is brought up to a marriageable age in an environment incompatible with her nature; each, without knowing why, is perennially at odds with her surroundings. Each must be restored to her rightful place — that is, her true home — for one of those happy endings in which the nineteenth century could still believe. Dance Insider, Vignettes 09/26/02