The torture can be increased by hanging weights from the feet, as well as swinging the victim to and fro in an arc.
Not the Pendulum of "The Pit and the Pendulum" fame, in which the pendulum dispatches the victim, but a pendulum created by the prisoner hanging from a rope by the wrists with the arms bound behind the back. This of course caused an extreme dislocation of the shoulders as the arms are stretched above the head.
Trivia & Comment
A modern day equivalent is to be locked in handcuffs and lifted into the air by the wrists.