other Properties and Practices; how explained. Case of Veracious
Hallucination. Riding Home from Mess. Another Case. The Bright
Scar. The Vision and the Portrait. Such Stories not usually
believed. Cases of Touch: The Restraining Hand. Of Hearing: The
Benedictine's Voices; The Voice in the Bath-room. Other "Warnings".
The Maoris. The Man at the Lift. Appearances Coincident with Death.
Others not Coincident with Anything.

In "crystal-gazing" anybody can make experiments for himself and among
such friends as he thinks he can trust. They are hallucinations
consciously sought for, and as far as possible, provoked or induced by
taking certain simple measures. Unsought, spontaneous waking
hallucinations, according to the result of Mr. Galton's researches,
though not nearly so common as dreams, are as much facts of _sane_
mental experience. Now every ghost or wraith is a hallucination. You
see your wife in the dining-room when she really is in the drawing-
room; you see your late great-great-grandfather anywhere. Neither
person is really present. The first appearance in popular language is
a "wraith"; the second is a "ghost" in ordinary speech. Both are
hallucinations.

So far Mr. Galton would go, but mark what follows! Everybody allows
the existence of dreams, but comparatively few believe in dream
stories of _veracious_ dreams. So every scientific man believes in
hallucinations, {68} but few believe in _veracious_ hallucinations. A
veracious hallucination is, for our purpose, one which communicates
(as veracious dreams do) information not otherwise known, or, at
least, not known to the knower to be known. The communication of the
knowledge may be done by audible words, with or without an actual
apparition, or with an apparition, by words or gestures. Again, if a