Some further consideration was necessary in placing the maps, and the Appendix appeared to me to be by far the most proper part for them. The maps, whether such as are general of the country, or those adapted to serve particular itineraries, should always be laid open before the reader, till he has made himself perfectly master of the bearings and distances of the principal rivers, mountains, or provinces where the scene of action is then laid. Maps that fold lie generally but one way, and are mostly of strong paper, so that when they are doubled by an inattentive hand, contrary to the original fold they got at binding, they break, and come asunder in quarters and square pieces, the map is destroyed, and the book ever after incomplete; whereas, even if this misfortune happens to a map placed in the Appendix, it may either be taken out and joined anew, or replaced at very little expence by a fresh map from the bookseller. I shall detain the reader but a few minutes with what I have further to say concerning the particular subjects of Natural History of which I have treated. The choice I know, though it may meet with the warmest concurrence from one set of readers, will not perhaps be equally agreeable to the taste of others. This I am heartily sorry for. My endeavour and wish is to please them all, if it were possible, as it is not. The first subject I treat of is trees, shrubs, or plants; and in the selecting of them I have preferred those which, having once been considered as subjects of consequence by the ancients, and treated largely of by them, are now come, from want of the advantage of drawing, lapse of time, change of climate, alteration of manners, or accident befallen the inhabitants of a country, to be of doubtful existence and uncertain description; the ascertaining of many of these is necessary to the understanding the classics.