element of "rubbish" in the catalogue; while a moment's thought will show the impossibility of making the librarian a censor, and allowing him to exclude whatever might not square with his prejudices or fancies. A considerable part of the catalogue, therefore, must be devoted to recording publications of little intrinsic value, but even here there is an important reservation to be made. Time, which in so many instances abates the value of what is really precious, makes in a fashion amends by bestowing worth on what was once of little account. What would we not give for a Court Gazette of the days of Augustus, or a list of odds at the Olympic games? There is absolutely no telling what value the most insignificant details of the nineteenth century may possess for the nineteenth millennium: even now men of letters might find the same intellectual stimulus in many a trivial page of the Museum Catalogue, as a distinguished living orator is said to find in Johnson's Dictionary. Next to this automatic factor in the increase of the catalogue may be named the element of seeming accident—the addition to the library of various classes of books, now at one time, now at another, as apparent chance, but actual law has prescribed. If we can imagine the various constituents of the Museum Library piled upon one another in chronological sequence, and a shaft driven down from the top, we may conceive ourselves coming upon a succession of strata, as the geologist finds when he bores for coal, or the archaeologist when he explores the site of a city
