This is sufficiently proved by the successive publication of SIX extensive Editions, three of which have appeared within the last twenty years, and it is well known that the SUPPLEMENT to the last of these Editions, completed in six volumes in 1824, attained a degree of celebrity never before reached by any similar undertaking in this country. But whilst it must be admitted to be one of the most valuable, it is also one of the cheapest publications of the day. If the quantity and quality of the matter, as compared with the price (not to mention the superior style in which both the printing and engraving are executed), be taken into account, this will be too evident to require further illustration. Every part indeed contains an interesting collection of Philosophical Disquisitions, Scientific Treatises, and articles on History and Biography, by the most eminent authors in these several departments, each of them respectively embracing the newest discoveries, the most recent improvements, or the latest information, which the progress of knowledge has supplied. These contributions, therefore, besides possessing the interest of entirely new works periodically issuing from the press, will, when completed, form THE MOST VALUABLE DIGEST OF HUMAN KNOWLEDGE THAT HAS YET APPEARED IN BRITAIN, IN THE CONVENIENT FORM OF A DICTIONARY. To those who value the acquisition of Useful Knowledge, this Work, accordingly, offers peculiar advantages; nothing being admitted into its pages of a frivolous or ephemeral description, or unfavourable to the best interests of morals or revealed religion; and every part being corrected, improved, remodelled, or enlarged, so as not only to enhance the general value of the work in a literary point of view, but at the same time to bring down the information in each department to the date of publication. The additions which have thus been made, both in the way of amending former articles, and introducing, in every branch of science, literature, and general knowledge, a very great number of new contributions, expressly written for the purpose, are perhaps without precedent in any similar undertaking; and, upon the whole, the present is not so much a new edition of the ENCYCLOPAEDIA BRITANNICA as a new work under that title. In every view, therefore, no periodical can be more beneficially put into the hands of the young, who can scarcely fail to find some source of attraction in every Part of it, and who, in the course of the publication, must acquire a stock of information altogether invaluable. In the execution of the numerous improvements which are in course of being made in every part of the Work, the Editor is aided by those eminent scientific and literary men whose co-operation he enjoyed in the preparation of the Supplement, as well as by many other Contributors of distinguished reputation, both in this country and on the Continent. * * * * * MODE AND TERMS OF PUBLICATION.