106. Sixth Class – BOISTEROUS AND DISRUPTIVE SPIRITS. – Strictly speaking, these spirits do not form a clear-cut category based on their personal qualities, they may even belong to any of the third order classes. They often reveal themselves by producing of phenomena perceptible to people, such as knocking, the movement and abnormal displacement of inert bodies, rustling the air, and other similar occurrences. They appear to be attached to matter more than any other type of spirit, and are the principal agents in determining changes in the physical elements, air, water, fre, or in the entrails of the earth. Whenever these phenomena present a deliberate or intelligent nature, a random, physical cause should never be assumed. All spirits can produce physical phenomena, but elevated spirits usually leave them to the devices of lower spirits, who are more suitable to act upon matter than intelligent matters. When higher spirits deem that manifestations of this nature are of some noble use, they employ subordinate spirits as their aids.