Modern Superstition regarding Ghosts--American 'Spiritualism'--Welsh Beliefs--Classification of Welsh Ghosts--Departed Mortals--Haunted Houses--Lady Stradling's Ghost--The Haunted Bridge--The Legend of Catrin Gwyn--Didactic Purpose in Cambrian Apparitions--An Insulted Corpse--Duty-performing Ghosts--Laws of the Spirit-World--Cadogan's Ghost. I. In an age so given to mysticism as our own, it is unnecessary to urge that the Welsh as a people are not more superstitious regarding spirits than other peoples. Belief in the visits to earth of disembodied spirits is common to all lands. There are no doubt differences in the degree of this belief, as there are differences in matters of detail. Where or how these spirits exist are questions much more difficult to the average faith than why they exist. They exist for the moral good of man; of this there prevails no doubt. The rest belongs to the still unsettled science of the Unknowable. That form of mysticism called 'spiritualism' by its disciples is dignified to the thoughtful observer by being viewed as a remnant of the primeval philosophy. When we encounter, in wandering among the picturesque ghosts of the Welsh spirit-world, last-century stories displaying details exactly similar to those of modern spiritualism, our interest is strongly aroused. The student of folk-lore finds his materials in stories and beliefs which appear to be of a widespread family, rather than in stories and beliefs which are unique; and the spirit of inquiry is constantly on the alert, in following the details of a good old ghost story, however fascinating it may be in a poetic sense. The phantoms of the Welsh spirit-world are always picturesque; they are often ghastly; sometimes they are amusing to the point of risibility; but besides, they are instructive to him whose purpose in studying is, to know.