Between Mr. Riley and Mr. Frasca , William Kanengiser pulled the program back to Spain for a set of gracefully played pieces by Fernando Sor -LRB- who actually spent much of his life outside Spain , but never mind -RRB- , and Jason Vieaux added a fleet reading of Sor 's Variations on a Theme From Mozart 's '' Magic Flute '' and a dazzling showpiece by the mid-19th-century composer Julian Arcas .