Table-turning

Their conclusion rested on the supposed elimination of all known physical causes for the movements; but it is doubtful from the description of the experiments whether the precautions taken were sufficient to exclude unconscious muscular action (the ideomotor effect) or even deliberate fraud.

The general public were content to find the explanation of the movements in spirits, animal magnetism, Odic force, galvanism, electricity, or even the rotation of the earth.

[3] In France, Allan Kardec studied the phenomenon and concluded in The Book on Mediums that some communications were caused by an outside intelligence, as the message contained information that was not known to the group.

The Scottish surgeon James Braid, the English physiologist W. B. Carpenter and others pointed out that the phenomena could depend upon the expectation of the sitters, and could be stopped altogether by appropriate suggestion.

[13][14] Faraday's work was followed up a century later by clinical psychologist Kenneth Batcheldor who pioneered the use of infrared video recording to observe experimental subjects in complete darkness.

[15] According to John Mulholland: The multiplicity of methods used to tip and raise tables in a séance is almost as great as the number of mediums performing the feat.