Spiritualism, another member of the modern occult family, presents a combination of features rather difficult to portray; but its public career of half a century has probably rendered its tenets and practices fairly familiar. For, like other movements, it presents both doctrines and manifestations, and, like other movements, it achieved its popularity through its manifestations and emphasized the doctrines to maintain the interest and solidarity of its numerous converts. Deliberate fraud has been repeatedly demonstrated in a large number of alleged ‘spiritualistic’ manifestations; in many more the very nature of the phenomena and of the conditions under which they appear is so strongly suggestive of trickery as to render any other hypothesis of their origin improbable and unnecessary. Unconscious deception, exaggerated and distorted reports, defective and misleading observation have been demonstrated to be most potent reagents, whereby alleged miracles are made to throw off their mystifying envelopings and to leave a simple deposit of intelligible and often commonplace fact. That the methods of this or that medium have not been brought within the range of such explanation may be admitted, but the admission carries with it no bias in favor of the spiritualistic hypothesis. It may be urged, however, that where there is much smoke there is apt to be some fire; yet there is little prospect of discovering the nature of the fire until the smoke has been completely cleared away. Perhaps it has been snatched from heaven by a materialized Prometheus; perhaps it may prove to be the trick of a _ridiculus mus_ gnawing at a match. However, the main point to be insisted upon with regard to such manifestations is that their interpretation and their explanation demand technical knowledge and training, or at least special adaptability to such pursuits. “The problem cannot be solved and settled by amateurs, nor by ‘common sense’ that Delivers brawling judgments all day long, On all things unashamed.”