to depend, must be immeasurably greater than in tedious experiments with cards and pictures. To a man whose experience of illumination was restricted to a rushlight it would appear incredible that the same familiar energy could cross the gulf which separates the earth from Sirius.
As regards the second point, the difference in the nature of the impression made upon the percipient's mind may probably throw some light on the mechanism of the transmission. In experimental cases we often meet with the transmission of a detailed scene. It is but rarely in the spontaneous cases—and then as a rule only in dreams or some state analogous to somnambulic clairvoyance—that we find details of the agent's actual appearance and surroundings accurately reflected in the percipient's mind. The apparition commonly consists simply of a figure, clothed as the percipient was accustomed to see the agent clothed; whereas to be true to life the phantasm would as a rule have to appear in bed. In cases where the vision gives no information as to the agent's clothing and surroundings generally—and, as already said, such cases form the great majority of the well attested narratives—we may suppose that what is transmitted is not any part of the superficial content of the agent's consciousness, but an impression from the underlying massive and permanent elements which represent his personal identity. The percipient's imagination is clearly competent to clothe such an impression with appropriate imagery, must
