My task, as editor, has been a simple one. I have rejected only those notes which have no value apart from the main work--glossarial notes, for instance, giving the English of the proper names occurring in the Arabian Nights; disquisitions on the probable date of the composition of the tales; and others inseparably connected with the stories themselves. The rest I have arranged in a series of chapters, interweaving the shorter notes in the longer, and giving as far as possible an air of unity to each division. Beyond such verbal alterations as were required by the separation of the notes from the text to which they referred, occasional changes in punctuation, and a slight alteration in the spelling of Oriental names in accordance with my great-uncle's latest method, I have not interfered with the form of the notes as they appeared in the edition of 1859. Such insignificant changes as I have made, I think I may state with confidence, would have been approved by the author. Beyond a few notes distinguished by square brackets, a new and very minute index (in which all Arabic words are explained), and a list of the authorities quoted, I have added nothing of my own. It may be objected to the title of the book that a considerable part of the notes is composed of recollections of Mr. Lane's personal experiences in Cairo in the early part of the present century. The subject-matter, however, is really mediæval. The notes have all the same purpose: to explain the conditions of life and society as they were at the time when the "Thousand and One Nights" assumed their present collected form. Upon various grounds Mr. Lane placed this redaction or composition at about the end of the fifteenth century. Accordingly, a large proportion of these notes consist of extracts from the more famous Arabic historians and other authors of the later Middle Ages, such as Ibn El-Jowzee (who died in A.D. 1256), El-Ḳazweenee (1283), Ibn-el-Wardee (1348), Ibn-Khaldoon (1406), El-Maḳreezee (1441), Es-Suyooṭee (1505), who all knew Arabian society in precisely the state described in the "Thousand and One Nights." Most of these authorities were unpublished when the notes were written, and Mr. Lane's quotations are from manuscripts in his own possession. Some are still inedited; and though many have been printed at the Booláḳ Press and elsewhere, it is surprising how little they have been used by European authors.