How far mankind would have benefited, by the introduction of a fresh mode of intoxication, I leave to the reflection of those sages, whose duty it would have become to appreciate its value, as an additional source of revenue to the state. But when I consider the delight with which stories of apparitions are received by persons of all ages, and of the most various kinds of knowledge and ability, I cannot help feeling some degree of complacency, in offering to the makers and readers of such stories, a view of the subject, which may extend their enjoyment far beyond its former limits. It has given me pain to see the most fearful and ghastly commencements of a tale of horror reduced to mere common events, at the winding up of the book. I have looked, also, with much compassion, on the pitiful instruments of _sliding pannels_, _trap-doors_, _back-stairs_, _wax-work figures_, _smugglers_, _robbers_, _coiners_, and other vulgar machinery, which authors of tender consciences have employed, to avoid the imputation of belief in supernatural occurrences. So hackneyed, so exhausted had all artificial methods of terror become, that one original genius was compelled to convert a mail-coach, with its lighted lamps, into an apparition. Now I freely offer, to the manufacturers of ghosts, the privilege of raising them, in as great numbers, and in as horrible a guise as they may think fit, without offending against true philosophy, and even without violating probability. The highest flights of imagination may now be indulged, on this subject, although no loop-hole should be left for mortifying explanations, and for those modifications of terror, which completely baulk the reader’s curiosity, and disgust him with a second reading. Another great convenience will be found in my system; apparitions may be evoked, in open day,--at noon, if the case should be urgent, in the midst of a field, on the surface of water, or in the glare of a patent-lamp, quite as easily, as in the ‘darkness of chaos or old night.’ Nay, a person rightly prepared may see ghosts, while seated comfortably by his library-fire, in as much perfection, as amidst broken tombs, nodding ruins, and awe-inspiring ivy. To those unfortunate persons, who feel a real dread of apparitions, I hope to offer considerations which will quiet their fears, and will even convert the horrors of solitude into a source of rational amusement. But I must forbear to display all the utility of this treatise, lest my reader should imagine that I am copying Echard’s mock-panegyric on his own dialogues. Take courage, then, good reader, and knock at the portal of my enchanted castle, which will be opened to you, not by a grinning demon, but by a very civil person, in a black velvet cap, with whom you may pass an hour not disagreeably.