But the forces of superstition and charlatanry, to which this vast territory has been ceded for so long, have bequeathed an unfortunate legacy to those who would now colonise it in the name of Science; and the preliminary difficulties of the undertaking can perhaps most effectually be met by a frank recognition of that fact. On the one hand, a large number of thinking men have been repelled, and still feel repulsion, from a subject whose record is so unsavoury. On the other hand, the appetite for the marvellous which has been so long unchecked is not easily restrained. The old habits of inaccuracy, of magnifying the proportions of things, of confusing surmises with facts, cannot be eradicated without long and careful discipline. To one writer, indeed, those dangers seemed so serious that he solemnly warned the Society for Psychical Research, at the outset of its career, against the risk of stimulating into disastrous activity inborn tendencies to superstition, by even the semblance of an inquiry into these matters. Without going to such lengths, it may be conceded to the critic that even with those who endeavour to apply scientific methods to the investigation the mental attitude is liable to be warped by the environment, and that here, as elsewhere, evil communications may corrupt. As regards the actual investigators this difficulty is growing less serious, as more men who have received their training in other branches of science are attracted to the inquiry, and as the affinities of the subject to long-recognised departments of knowledge become daily more apparent. In another direction, however, this mental attitude presents still a more or less formidable obstacle. Many of the observations on which students of the subject are compelled to rely are derived from persons who have had no training in such habits of accuracy as are required in scientific research. When accounts of the ornithorhynchus first reached this country naturalists laughed at the traveller's tale of a beast with the tail of a beaver and the bill and webbed feet of a duck. In the same way scientific men for long refused to admit the existence of aerolites, as they now decline to credit the reports of a Sea Serpent of colossal proportions. In all these cases, so long as the alleged facts rest solely on the testimony of men untrained in habits of close observation and accurate reporting, a suspension of judgment seems to be justified. And if these considerations are valid in ordinary cases, a much higher degree of caution may be reasonably demanded of investigators who leave the neutral ground of the physical sciences to enter upon a field in which the emotions and sympathies are most keenly engaged, and in which the incidents narrated may have served to afford support to the dearest hopes and sanction to the deepest convictions of the narrator. So insidious, in such a case, is the work of the imagination, so untrustworthy is the memory, so various are the