To make this complete organization of a library successful, one must have an organising mind, a wide acquaintance with literature, history, and the outlines, at least, of all the sciences; a knowledge of the ancient and of various modern languages; a quick intuition, a ripe judgment, a cultivated taste, a retentive memory, and a patience and perseverance that are inexhaustible. Even were all these qualities possessed, there will be in the arrangement elements of discord and of a failure. A multitude of uncertain points in classification, and many exceptions will arise; and these must of necessity be settled arbitrarily. The more conversant one becomes with systems of classification, when reduced to practice, the more he becomes assured that a perfect bibliographical system is impossible. Every system of classification must find its application fraught with doubts, complications, and difficulties; but the wise bibliographer will not pause in his work to resolve all these insoluble problems; he will classify the book in hand according to his best judgment at the moment it comes before him. He can no more afford to spend time over intricate questions of the preponderance of this, that, or the other subject in a book, than a man about to walk to a certain place can afford to debate whether he shall put his right foot forward or his left. The one thing needful is to go forward. Referring to the chapter on bibliography for other details, I may here say that the French claim to have reached a highly practical system of classification in that set forth in J. C. Brunet's _Manuel du Libraire_. This is now generally used in the arrangement of collections of books in France, with some modifications, and the book trade find it so well adapted to their wants, that classified sale and auction catalogues are mostly arranged on that system. It has only five grand divisions: Theology, Law, Arts and Sciences, Belles-lettres, and History. Each of these classes has numerous sub-divisions. For example, geography and voyages and travels form a division of history, between the philosophy of history and chronology, etc. The classification in use in the _Bibliotheque nationale_ of France places Theology first, followed by Law, History, Philosophy and Belles-lettres. The grand division of Philosophy includes all which is classified under Arts and Sciences in the system of Brunet.