You hear most often of raps or knocks, but even these can be whisper soft thuds to ear-shattering BANGS coming from furniture, walls, floors, the ground or the air. They may sound like scratches, hammering or even voices, speaking or singing.
Several scientists have analyzed recordings of raps produced at séances
and compared them with knocks made normally and found differences. The
normal knocks start with a strong vibration and slowly fade, while the
anomalous raps do the opposite—start small and build to a climax. ...<<<Read More>>>....
