Some readily observable phenomena have suggested a connection between psychic abilities and magnetism. The medium Henry Slade could influence the movements of a magnetic needle. Johann Zöllner made convincing experiments with a glass-covered compass. Slade could also magnetize steel knitting needles, and Zöllner lifted iron filings and sewing needles with their ends. Stanislawa Tomczyk could exert a similar influence over the compass.
The British psychic researcher and author Stanley de Brath also reported a case in which a young man deflected the magnetic needle. He was searched for a concealed iron or a magnet but nothing was found.
More recently, the controversial psychic Uri Geller has also demonstrated deflection of a compass needle, while his skeptical critics also claim that he must have a concealed iron or magnet.