{58} These things are as unfamiliar to men of science as Mr.Galton found ordinary mental imagery, pictures in memory, to be.

Psychology may or may not include them in her province; they may or may not come to be studied as ordinary dreams are studied.

But, like dreams, these crystal visions enter the domain of the ghostly only when they are _veracious_, and contribute information previously unknown as to past, present or future.

There are plenty of stories to this effect.

To begin with an easy, or comparatively easy, exercise in belief.
UNDER THE LAMP I had given a glass ball to a young lady, who believed that she could play the "willing game" successfully without touching the person "willed," and when the person did not even know that "willing" was going on.