Theatrical Mouth Of Hell
Lodovico Burnacini's set design, "Hell Mouth" (engraving by Mathäus Küsel) displays a scene from the 1668 production of the opera Il Pomo D'Oro, by Antonio Cesti.
The above images come from The Valenciennes Passion play (Bibl. Nat. MS. fr. 12536). (From Gazette des Beaux-Arts, 1904, vol I., p. 393).
"In the above example, Paradise is located on top of a pavilion on the left, while the mouth of Hell spews demons from a building on the right. A pond with a boat in it is labelled as the sea, while various other structures, including what appear to be the town gates, are labelled as the Temple, Nazareth, Jerusalem and other significant places in the play." - quote source.
"In medieval theatre, a hellmouth was a prop or mechanical device which was used to attempt to scare the audience by vividly dramatizing an entrance to Hell. " - quote source
A large number of the artworks that I will be posting are likely direct copies of real props of a Hellmouth. The pic below is the only copy I've seen where the Hellmouth is actually closed. There was probably some crude mechanical device inside allowing it to open and shut for the actors dressed as demons and tortured souls to pass through.