Lewiston’s Oasis of Music concludes its first season of free concerts with a performance of baroque and early classical music by the Bow and String Band at Trinity Church, 247 Bates St., from 12:30-1 p.m. The Bow and String Band —  Mark Nordberg on the seven-string bass viola da gamba, Greg Boardman on viola and Barbara Oliver on cello — tune their already dark-sounding instruments a half-step lower in pitch in order to more closely reproduce the musical sounds of the era these pieces come from. The program will include music of Monteverdi, Telemann and Haydn, whose Baryton Trios were composed for a patron who performed on the nearly-extinct instrument the trios are named for. Nordberg will play the part of the baryton on his viol.  A potluck snack reception will follow the recital; punch will be provided.  FMI: call 344-3106.