aulaeum : au-LAH-e-um

(Latin; pl. aulaea: drop curtain or stage curtain).  The aulaeum was the mechanically operated main curtain of the Roman theatre, positioned immediately behind the proscaenium wall and lowered into a specialized slot at the beginning of a performance to reveal the stage, then raised at the conclusion. Introduced to Rome in 133 BC, the aulaeum operated contrary to modern practice—being lowered to begin a show rather than raised. Archaeological evidence reveals the curtain mechanism consisted of wooden masts attached to the fabric that fitted into stone blocks set at intervals in a slot 3-5 meters deep, running the full width of the stage. Not to be confused with siparia (smaller, portable stage curtains).   Also see Greek: katablêma.