Paula M. Kimper and Wende Persons have been working for the last two years on an operatic version of "Patience and Sarah," Isabel Miller's novel about two early 19th-century Connecticut women who fell in love and became pioneers. American Opera Projects, at 463 Broome Street in SoHo, has presented several workshop versions of the piece over the past year and offered a semi-staged final draft, with piano accompaniment, last week. The final performance took place on Saturday.

Ms. Persons has written a logically shaped libretto in which the first act is devoted to the attraction between the comparatively well-off Patience White, who lives with her brother and his wife, and Sarah Dowling, the tomboyish daughter of a nearby farmer. Patience's plan to go west with Sarah crumbles in the face of her family's objections, and in the second act Sarah travels on her own, disguised as a boy. She is hired as an assistant by Parson Daniel Peel, a kindly itinerant bookseller who, believing that Sarah is a boy, confesses to an attraction to her. The third act brings Sarah back to her family and to Patience, who this time has the courage to leave with Sarah.

Ms. Kimper has set this to an accessible, attractively lyrical score that suggests the early 19th-century setting by drawing occasionally on hymn tunes and a gloss of the parlor song style. Generally, though, her language is full of almost impressionistic harmonic touches; indeed, Sarah has a gorgeous, Ravelian aria at the start of the second act.

This being a work-in-progress, there are aspects of the piece that Ms. Persons and Ms. Kimper are likely to reconsider. The frequent hops between Patience's and Sarah's homes, for example, make for a needlessly complicated staging, and some scenes could be profitably dropped or compressed. At close to three hours, the music, well-wrought though it is, begins to cloy in the final scenes.

Lori Ann Philips, as Patience, and Elaine Valby, as Sarah, created their characters effectively and sang powerfully. Michael Hendrick, as Patience's brother Edward, and Barton Green, as Peel, made strong contributions.