Beside the verse dramas, with their lyrical interludes, on which many operas were based, there were poetic texts which were set as secular cantatas. One of the earliest was Alessandro Stradella's "La Circe", in a setting for three voices that bordered on the operatic. It was first performed at Frascati in 1667 to honour Cardinal Leopoldo de Medici and contained references to its surroundings. In the opening recitative, Circe explains that it was her son Telegonus who founded Frascati. The other characters with whom she enters into dialogue are the south wind (Zeffiro) and the local river Algido. In the following century, Antonio Vivaldi's cantata "All'ombra di sospetto" (In the shadow of doubt, RV 678) is set for a single voice and depicts Circe addressing Ulysses. The countertenor part is accompanied by flute, harpsichord, cello, and theorbo and features two recitatives and two arias. The piece is famous for the dialogue created between flute and voice, conjuring the moment of flirtation before the two become lovers.