When Lafeuillade and Cassel began singing the celebrated duet. "Amour sacre de la patrie" enthusiasm exploded irresistibly and singers found it necessary to start afresh in the midst of the cheering. Finally, when Masaniello (Lafeuillade) launched into his entreaty, the invocation "Aux armes!", the public could no longer be restrained. They acclaimed aria and actor, they booed the fifth act in order to stop the performance, and the delirious crowd itself out of the hall—into history. Welcomed by the other crowd which waited outside, it joined in the demonstrations which loosed the revolution of 1830.