NEW ISSUE OF THE ENCYCLOPAEDIA BRITANNICA, SEVENTH EDITION. _On the Twelfth of July was published, price Three Shillings, to be continued every alternate Week,_ PART I. OF THE ENCYCLOPAEDIA BRITANNICA, REVISED, CORRECTED, AND IMPROVED; AND INCLUDING THE SUPPLEMENTS TO THE LAST TWO EDITIONS. _With Introductory Dissertations on the History of the Sciences,_ BY PROFESSORS DUGALD STEWART, PLAYFAIR, & LESLIE, AND BY THE RIGHT HON. SIR JAMES MACKINTOSH. _Illustrated by a New Set of Engravings on Steel, and compiling a complete Series of Folio Maps engraved by Sydney Hall._ EDITED BY PROFESSOR NAPIER. The extraordinary circulation attained by many of the cheap publications of the day has suggested to the Proprietors of the ENCYCLOPAEDIA BRITANNICA, that if a work of high and established character were offered to the public, at a price and in a form accommodated to the demands of the age, the support which it might reasonably anticipate would be proportionally liberal. In accordance with this view, they have resolved to commence a New Issue of the ENCYCLOPAEDIA BRITANNICA, in a form which will bring it within the reach of all classes of the community. This valuable work forms an Alphabetical Repertory of every branch of human knowledge. It was the first work of the class which aspired to embrace all the departments of learning, to render the alphabet a ready key, not only to the _Arts and Sciences_, but to the multiplied details of _History_, _Biography_, _Geography_, and _Miscellaneous Literature_;--and it was also the first in which the Sciences themselves were treated in a form at once consistent with alphabetical arrangement and systematic exposition. By the successive labours of the learned Contributors to its different editions, its pages have been stored with a mass of valuable and varied information. In its third edition, it became, through the numerous contributions of the late PROFESSOR ROBISON, the most complete Digest of the modern improvements in Physics that had yet been presented to the British Public; and in the fourth, it was raised, by means of those of PROFESSOR WALLACE, to a similar eminence in the Mathematical Sciences. The compass and variety of its plan and information, the general ability of its execution, and its approved method of treating the Sciences, have, in a word, given it so decided a preference in public favour, that its popularity, instead of suffering any diminution from rivalship, has continued to increase to the present day.