"In answer to inquiries, Mr C----n adds: 'I never at any other time had a feeling in any way resembling the particular time I wrote about. At the time I wrote about I was in perfect health, and in every way in comfortable circumstances.'"
There is nothing unreasonable in the assumption that telepathy is the agency primarily concerned in these manifestations. The idea having been received, a hallucination is built up, so to speak, by the percipient. A truly hallucinable person can suggest to himself his own hallucinations with no external aid, but a non-hallucinable personage cannot induce these hallucinations at all. Dr Hugh Wingfield stated to the Society for Psychical Research that the case of one of his patients proved that hallucinations could be produced by self-suggestion. "He could, by a simple effort of the mind, himself believe almost any delusion--_e.g._ that he was riding on horseback, that he was a dog, or anything else, or that he saw snakes--if left to himself the delusion vanished slowly. Anyone else could remove it at once by a counter-suggestion. He made," he adds, "these experiments without my consent, as I consider them unsafe."
Hallucination is at times accompanied by curious organic effects. One of the commonest of these is a feeling of cold--generally described as a "chill" or "cold shudder." The following example is taken from the Census of Hallucinations of the Society for Psychical Research:--
"[About twenty years ago] I was about ten years old, and was staying with friends in Kensington. Between the hours of eight and nine P.M., we were all sitting in the drawing-room with the door open, [it] being a very warm evening. Suddenly I experienced a cold shudder, and on looking through the door opposite which I was sitting, I saw the figure of a little old lady dressed in a long brown cloak with a large brown hat, carrying a basket, glide down the stairs and disappear in the room next the drawing-room. The impression was that of someone I had never seen. I was talking on ordinary subjects, neither ill, in grief, or anxiety. There were several other people in the room, but no one noticed anything but myself. I have never had any experience of this kind before or since."