My brother was hurrying home from his dance, with some little self-reproach in his mind for not having been at his chambers to receive his guest, so the chances are that he was thinking of me. The whole scene was vividly present to me at the moment, but I did not note particulars any more than one would in real life. The general impression was of a narrow landing brilliantly illuminated, and I remember verifying the correctness of this by questions at the time. This is my sole experience of the kind. [The last words are in answer to the question whether he had had similar vivid visions which had _not_ corresponded with any real event.] The impression here produced is as though a jerk were given to some delicate link connecting the two brothers. The brother suffering the crisis thinks vividly of the other; and one can of course explain the incident, as we did on its first publication, as the endangered man's projection of the scene upon his brother's mind. The passive dozing brother, on the other hand, feels as though he were suddenly _present_ in the scene,--say in response to some sudden call from the brother in danger,--and I am here bringing into relief _that_ aspect of the incident, on account of its analogy with cases soon to be quoted. But the main lesson no doubt may be that no hard and fast line can be drawn between the two explanations.[51] And here I feel bound to introduce a sample of a certain class of dreams,--more interesting, perhaps, and certainly more perplexing than any;--but belonging to a category of phenomena which at present I can make no attempt to explain. I mean precognitive dreams;--pictures or visions in which future events are foretold or depicted, generally with more or less of symbolism,--and generally also in a mode so remote from the previsions of our earthly sagacity that we shall find ourselves driven, in a later discussion, to speak in vague terms of glimpses into a cosmic picture-gallery;--or of scenic representations composed and offered to us by intelligences higher and more distant than any spirit whom we have known. I give in Appendix IV. C, a thoroughly characteristic example;--characteristic alike in its definiteness, its purposelessness, its isolated unintelligibility.