The system generally followed, as we have already mentioned, is that of Mudd ; which divides books into the five great classes of Theology, Jurisprudence, Sciences and Arts, Belles Letires, and History. Each of these classes has divisions and subdivisions more or less numerous, according to the number of the branches to be distinguished ; and it is in the distri bution of these, that the chief differences are found in foreign Catalogues ; though the divisions and sub- . divisions of De Bure, as exemplified in his Biblio graphic Instructive, are those commonly followed. Some Bibliographers, however, have proposed to alter the to diminish, and some to increase the number of the primitive classes; while a few have proposed systems altogether different, and greatly more refined in their principles of classification. M. Ameilhon, in a paper published in the Memoirs of the French Institute, proposes the following leading divisions: Grammar, Logic, Morals, Jurisprudence, Metaphysics, Physics, Arts, Belles Lettres, and History. t In this arrange- ' meat, Theology, to which he has great objections as a separate class, is transferred, with evident impro priety, to the class of Metaphysics. M.-Camus has also investigated the principles according to which Books ought to bnclassed, in another paper in these Memoirs, already quoted ; but, as be has not re duced his method, which proceeds on views much too fanciful for the purpose, to specific beads, we can only refer our readers to his paper. Equally remote from the proper objects of a classed Cata logue, are the systems proposed by M. Peignot, and by M. Thiebeut. t The former takes the well known speculations of Bacon and D'Alembert, as to the Genealogy of Knowledge, for the basis of his system; and thus fixes upon three principal heads or classes, under the names of History, Philosophy, and Imagi nation ; with the addition of Bibliography as an in troductory ekes. In the system of the latter, there are, in like manner, only three principal heads, founded upon a division of Knowledge, into know ledge Instrumental, Essential, and Suitable.
Germany has also produced a variety of Biblio graphical systems ; some of them as absurdly refined • AO those just mentioned ; while others, that of Leib. nits, for example, are better adapted to practical pur poses. The dassee proposed by this eminent Philooe pher are as fellows : Theology, Jurisprudence, Medi4 eine, Intelkettad Philosophy, Mathematics, Natural Philosophy, Philology, History, and Miscellanies.:* Another system, not very remote from this, is that proposed by M. Denis, keeper of the Imperial Li brary at Vienna ; in which books are divided into the classes of Theology, Jurisprudence, Philosophy, Medicine, Mathematics, History, and Philology. This system is developed in his Introduction to the Know ledge of Books, to be afterwards described.
Dr Middleton is the only British author, so far as we know, wbo has written any separate tract on the classification of Books. The classes proposed by him are these : Theology, History, Jurisprudence, Philosophy, Mathematics, Natural History, Medicine, Belles Lettres (Liters hums niones ), and Miscellanies. His object in the tract referred to, was to recommend the adoption of this arrangement for a Catalogue of the University Li brary of Cambridge ; and whatever may be its de fects, it cannot be questioned that a printed Cata logue of this collection so classed, would have proved of much utility ; and would have helped to wipe away that stain of remissness in this particular, which still unfortunately attaches to our great Uni versities.
Naude mentions a writer, who proposed to class all sorts of Books under the three heads of Morals, Sciences, and Devotion ; and who assigned, as the grounds of this foolish arrangement, these words of the Psalmist, Disciplinam, Bonitatem, et Scientism dote me. We confess, that all such systems as those of M.
Peignot and M. Thiebaut, when applied to the forma tion of Catalogues, appear to us quite as absurd as this system deduced from the Canticles. The re mark which Naude applied to it, that it seemed' in tended " to crucify and torture the memory by its oubtilties," is just as applicable to the former. That system, he adds (we use the words of Evelyn's Translation of his Avis pour dresser une Biblio theque), " is the best, which is most facile, the least intricate, and the most practised; and which follows the faculties of Theology, Physic, Jurisprudence, Mathematics, Humanity, and others." M. Ameilhon also objects decidedly to all over refined Bibliogra phical systems, and particularly to those which aspire to follow the genesis and remote affinities of the dif ferent branches of knowledge. " Vexecution," says he, " en seroit impossible; ou si elle ne l'etoit pas, au moins entraineroit-elle des difficultes, qui ne pourroient etre surmontees que par des hommes pro fondement refleches et exerces aux meditations me taphysiques." t The truth is, that when Bibliogra phers speculate in this field with a view to Catalogue making, they entirely forget their proper province and objects. They have nothing whatever to do with Genealogical Trees of knowledge, or with any mode of classing Books which is founded upon remote and arbitrary abstractions. The whole use and end of a Classed Catalogue is to furnish a index to Books, arranged according to their subjects ; and that arrangement is therefore to-be prefferred, "Rich is founded upon the most obviously marked, and ge nerally recognised divisions of those subjects. We may-add, that to compile a good Catalogue of an ex tensive Library, even • on this humbler plan, would require more ability, and more correctness of know ledge, than are often likely to be employed in such an undertaking.
Though we are not altogether satisfied with the division and order of the classes in the system cdm monly followed, we have no doubt, that by means of an additional class, and a correct arrangement of the subdivisions, a Catalogue might be formed, perfectly adequate to every useful purpose. We allude to a class, such as is partly indicated in the schemes both of Leibnitz and Middleton, for the reception of all Encycloptedical works, of Collections of treatises on various subjects, and Works of authors who cannot with propriety be limited to any one division of knowledge. M.. Camus thinks, that the latter de scription of works may be properly enough entered in the class in which their authors most excelled ; those of Cicero, for example, among the Ora tor: ; but, not to mention the evident incongruity of placing a collection, so multifarious as Cicero's works, under Oratory, there may sometimes be roots for uncertainty, as to the division under which, ac cording to this rule, an author's works ought to be sought. These incongruities and inconveniences, to gether with those which must arise from placing Encyclopaedias, and General Collections, under any of the common divisions, can only be reme died by . a Miscellaneous Class ; and while this class ought to indicate, in one of its divisions, the Collective Editions of an author's works, his separate treatises ought to be entered under the subjects to which they belong ; as, without this, the Classed Catalogue will not fully answer its purpose, of showing what has been written by the authors contained in it, • on the different branches of know ledge. Thus, a Catalogue compiled upon this plan, would not only be rendered more consistent in its arrangement, but much more complete as an index to the materials of study.