958. There are troops of spirits who wander about and whom other spirits greatly dread. They apply themselves to the lower part of the back, and inflict torture by rapid movements to and fro which no one can prevent, and which are attended with sound, and they direct the constrictive and expansive movement upward in the form of a cone with its point at the top; and whoever is introduced within this cone, especially toward the top of it, is miserably racked in every particle of his limbs. It is deceitful pretenders who are introduced into it and so punished.