Physical mediumship seance is a gathering of people who sit together, called a circle or seance in French, with the physical medium, bound, gagged and tied to a chair. the chair is typically behind a curtain or some such like this picture of Kai Muegge's home circle.
Under no light or subdued red or candlelight, the medium passes into trance and allows spirit (discarnates of "dead" people) to 'come through'. They (discarnates) will perform feats that defy or earthly physics such as levitation of the medium (chair and all), movement of object that are untouched by human hands, deliver messages to loved ones in the circle and bring in artifacts like gemstones, statuettes, crystalline structures that drop into the circle from out of nowhere e.g.
Fun for all! No experience even close to being alike this physical mediumship seance.
Google Warren Caylor and David Thompson for additional information.
I hold interviews, in person, and talk with a potential sitter. If they have spiritual references, more the better. What is accomplished is the removal of anyone who is judged to not be serious about discarnate-incarnate communications or could endanger the physical medium by interrupting the seance with tomfoolery.
Skepticism allowed, cynicism is not.
Sorry about the late answer, I am having a terrible time with Internet connectivity today.
It is much more usual than not the seances are attended by 'celebrity' spirits. Churchill, John Lennon, Quentin Crisp, Michael Jackson (just starting with him), Judy Garland, Geronimo, Louis Armstrong etc etc etc. They will play spirit or human instruments that you cannot see but easily hear, sing, converse, deliver messages. Churchill has a book he wants to be transcribed, over 670 pages, "Prime Minister's Views From Beyond the Veil" or something like that,