The phantom images of the retina are not perceptible in the light of the day.  Those that exist in the sensorium in like manner do not attract our attention so long as the sensory organs are in vigorous operation, and occupied in bringing new impressions in.  But, when those organs become weary or dull, or when we experience hours of great anxiety, or are in twilight reveries, or are asleep, the latent apparitions have their vividness increased by the contrast, and obtrude themselves on the mind.  For the same reason they occupy us in the delirium of fevers, and doubtless also in the solemn moments of death.  During a third part of our life, in sleep, we are withdrawn from external influences; hearing and sight and the other senses are inactive,but the never-sleeping Mind, that pensive, that veiled enchantress, in her mysterious retirement, looks over the ambrotypes she has collected—­ambrotypes, for they are truly unfading impressions—­and, combining them together, as they chance to occur, constructs from them the panorama of a dream.

Nature has thus implanted in the organization of every man means which impressively suggest to him the immortality of the soul and a future life.  Even the benighted savage thus sees in his visions the fading forms of landscapes, which are, perhaps, connected with some of his most pleasant recollections; and what other conclusion can be possibly extract from those unreal pictures than that they are the foreshadowings of another land beyond that in which his lot is cast?  At intervals he is visited in his dreams by the resemblances of those whom he has loved or hated while they were alive; and these manifestations are to him incontrovertible proofs of the existence and immortality of the soul.  In our most refined social conditions we are never able to shake off the impressions of these occurrences, and are perpetually drawing from them the same conclusions that our uncivilized ancestors did.  Our more elevated condition of life in no respect relieves us from the inevitable operation of our own organization, any more than it relieves us from infirmities and disease.  In these respects, all over the globe men are on an equality.  Savage or civilized, we carry within us a mechanism which presents us with mementoes of the most solemn facts with which we can be concerned.  It wants only moments of repose or sickness, when the influence of external things is diminished, to come into full play, and these are precisely the moments when we are best prepared for the truths it is going to suggest.  That mechanism is no respecter of persons.  It neither permits the haughtiest to be free from the monitions, nor leaves the humblest without the consolation of a knowledge of another life.  Open to no opportunities of being tampered with by the designing or interested, requiring no extraneous human agency for its effect, out always present with every man wherever he may go, it marvelously extracts from vestiges of the impressions of the past overwhelming proofs of the realities of the future, and, gathering its power from what would seem to be a most unlikely source, it insensibly leads us, no matter who or where we may be, to a profound belief in the immortal and imperishable, from phantoms which have scarcely made their appearance before they are ready to vanish away.