27. Spirits sometimes manifest spontaneously through noises and raps, which are frequently their way of attesting to their presence and calling attention to themselves - just like someone knocking on a door to let those inside know someone is there. There are spirits who do not limit themselves to causing moderate noises, but who go so far as to produce a racket that sounds like dinnerware breaking, doors opening and closing, or furniture being overturned. Some even cause real trouble and damage.