=Bibliography.=—The article on this subject by Mr. Pollard, is only concerned with bibliography as the art of examination, collation and description of books,—their enumeration and arrangement in lists for purposes of information, and further, with the literature of this subject, _i. e._ with the bibliography of bibliography. The examination and collation of books to discover whether they are perfect and in their original condition are especially important in the case of rare books, like incunabula and first editions, piracies and spurious imprints. Photographic forgeries of books can usually be detected by the tendency of all photographic reproduction to thicken letters and exaggerate every kind of defect. Some of these imitations are, however, very cleverly made on paper of the period of the original and so are very hard to distinguish from the latter. =Book Collecting= is sympathetically discussed by Mr. Pollard. The statement that the ultimate rarity of books varies in the inverse ratio of the number of copies originally printed, though recognized as a somewhat sweeping generalization, is conceded to be not far from the truth. No one thinks of collecting what is easily procurable at the moment. So long as the anticipation exists that a book will continue to be easily procurable the collecting impulse is restrained. Book collecting as a hobby is analyzed and the history of some notable private collections given. As Thomas Watts once said, the main office of private collections is to feed public institutions. =Libraries.=—This brings us to the article on Libraries, written jointly by H. R. Tedder and J. Duff Brown, an article of about 65,000 words and deserving of more than a passing notice. It is the latest conspectus of library history and activity and if printed separately might have made a book of several hundred pages which would have been duly reviewed in all the professional journals. The fact that it is in the Britannica insures it even wider publicity and in view of its excellence we feel that it is worth while calling to the particular attention of librarians. The general treatment divides the subject into Ancient libraries (3 pages) Mediaeval period (3 pages) and Modern libraries (26 pages). The first section has an archaeological rather than a professional interest, but the mediaeval period is of importance to us because in it is found the real origin of modern library organization. A rule of St. Benedict required the monks to borrow a book apiece and read it straight through. The books in the Benedictine monastery were kept in _armaria_, or chests; whence the name of the Benedictine librarian, _armarius_. The Carthusians are supposed to have been the first to lend books for use outside the monastery. The library at Cesena in Northern Italy is still preserved in its original condition. The Laurentian library at Florence was designed after monastic models.