The manifestation of physical phenomena such as table tipping, apports, the appearance of unusual lights, etc., usually during a séance. Usually it requires a state of trance on the part of the medium.
Readers, please enjoy this guest blog post by Sandra Kynes, author of several books, including The Herb Gardener's Essential Guide, Plant Magic, and the new Witches' Encyclopedia of Magical Plants, among many others.
Although a few old books...