The only supernatural agents which can in any manner be allowed to us moderns, are ghosts; but of these I would advise an author to be extremely sparing. These are indeed, like arsenic, and other dangerous drugs in physic, to be used with the utmost caution; nor would I advise the introduction of them at all in those works, or by those authors, to which, or to whom, a horse-laugh in the reader would be any great prejudice or mortification. As for elves and fairies, and other such mummery, I purposely omit the mention of them, as I should be very unwilling to confine within any bounds those surprizing imaginations, for whose vast capacity the limits of human nature are too narrow; whose works are to be considered as a new creation; and who have consequently just right to do what they will with their own. Man therefore is the highest subject (unless on very extraordinary occasions indeed) which presents itself to the pen of our historian, or of our poet; and, in relating his actions, great care is to be taken that we do not exceed the capacity of the agent we describe. Nor is possibility alone sufficient to justify us; we must keep likewise within the rules of probability. It is, I think, the opinion of Aristotle; or if not, it is the opinion of some wise man, whose authority will be as weighty when it is as old, “That it is no excuse for a poet who relates what is incredible, that the thing related is really matter of fact.” This may perhaps be allowed true with regard to poetry, but it may be thought impracticable to extend it to the historian; for he is obliged to record matters as he finds them, though they may be of so extraordinary a nature as will require no small degree of historical faith to swallow them. Such was the successless armament of Xerxes described by Herodotus, or the successful expedition of Alexander related by Arrian. Such of later years was the victory of Agincourt obtained by Harry the Fifth, or that of Narva won by Charles the Twelfth of Sweden. All which instances, the more we reflect on them, appear still the more astonishing. Such facts, however, as they occur in the thread of the story, nay, indeed, as they constitute the essential parts of it, the historian is not only justifiable in recording as they really happened, but indeed would be unpardonable should he omit or alter them. But there are other facts not of such consequence nor so necessary, which, though ever so well attested, may nevertheless be sacrificed to oblivion in complacence to the scepticism of a reader. Such is that memorable story of the ghost of George Villiers, which might with more propriety have been made a present of to Dr Drelincourt, to have kept the ghost of Mrs Veale company, at the head of his Discourse upon Death, than have been introduced into so solemn a work as the History of the Rebellion.