The Alleged Haunting of B House

For the benefit of those who are not aware of the fact it may be as well to state that the class of people known as spiritualists hold that when raps are heard it is the best thing for the hearer to say aloud If you are intelligent will you please to rap three times? and if this is done to ask the intelligence to rap three times for yes once for no and twice for doubtful.' (Excerpt from Text)