Dedicated, by permission, to Her Majesty. THE IMPERIAL CYCLOPÆDIA; In Parts, price HALF-A-CROWN. THE PUBLICATION COMMENCES WITH THE CYCLOPÆDIA OF THE BRITISH EMPIRE; WITH STEEL ENGRAVINGS, AND NUMEROUS COLOURED MAPS; TO BE COMPLETED IN twelve PARTS. THE most important and interesting features of a New Cyclopædia, must be the articles peculiarly relating to THE BRITISH EMPIRE. In our own country the great scientific improvements of the age have produced such rapid changes in the aspect of our cities and towns, and in the condition of our people, that new information is a matter of necessity for the man of business, of gratification for the inquiring tourist, and of earnest thought for every lover of his country. Such information, however, cannot in a work like this branch out into the minute details of parochial or family history. But even within the necessary limits of a geographical work, as distinguished from a topogra phical, a body of facts may be produced of universal value, when no labour is spared to ensure fulness and accuracy. Again, THE EXACT State of our COLONIAL POSSESSIONS, is a subject to which the public attention is directed with an earnestness never before witnessed; their physical geography, their political condition, their natural resources, their commerce, have become of universal importance to the people of the United Kingdom. FIVE PARTS HAVE BEEN PUBLISHED, up to November 1, HALF A CENTURY OF THE BRITISH EMPIRE; A HISTORY OF THE KINGDOM AND THE PEOPLE, FROM 1800 TO 1850. BY HARRIET MARTINEAU. To be published in SIX VOLUMES at SIX SHILLINGS each; and in Ir is intended to present, in the Library Form of a handsome Octavo, at a rate of great cheapness, a connected narrative of the most important æra in the history of the modern world. The celebrated work of Mr. Macaulay professes to be "The History of England from the Accession of King James the Second down to the time which is within the Memory of Men still living." HALF A CENTURY OF THE BRITISH EMPIRE' will chiefly deal with events and states of society during a time in which many of our contemporaries have lived and acted. 6 PART I. WILL BE PUBLISHED ON THE 1ST OF JANUARY, 1851. BRITISH EMPIRE: IN FORTY MONTHLY SHILLING PARTS, IN SMALL FOLIO, DRAWN AND ENGRAVED EXPRESSLY FOR THIS WORK, BY THE MOST EMINENT ARTISTS, And with splendid Line Engravings on Steel, FORMING FOUR SUPERB VOLUMES. RE-ISSUE IN SIXTEEN HALF-CROWN PARTS. On the 1st of November appeared the First Part of a Re-issue of this popular work, in Monthly Parts at HALF-A-CROWN. By this arrangement the new Periodical Subscribers will be enabled to complete the Series by the end of 1851. The war. Continuation of the Pictorial History of England; IN SIXTEEN HALF-CROWN PARTS. THE HISTORY OF ENGLAND DURING THE THIRTY YEARS' PEACE: 1816-1846. BY HARRIET MARTINEAU. HISTORY OF THE PEACE' is printed of an uniform size with the PICTORIAL HISTORY OF ENGLAND, of which the narrative terminates with the conclusion of the It forms Two splendid Volumes super royal octavo, with NUMEROUS PORTRAITS. Part 1 of the Re-issue in HALF-CROWN Parts appeared on the 1st of November 1850; so that the new Periodical Subscribers will be enabled to complete the Work by the end of 1851. THE PICTORIAL HISTORY OF FRANCE AND ITS REVOLUTIONS. BY GEORGE LONG, A.M. RE-ISSUE IN EIGHT HALF-CROWN PARTS. FORMING ONE SPLENDID volume, IMPERIAL OCTAVO, With Fifteen Portraits on Steel, and rumerous Wood-cuts. Maps OF THE SOCIETY FOR THE DIFFUSION OF THESE celebrated Maps, cheap as they are, combine every excellence that can be attained by the most careful supervision and the most liberal expenditure. Adequate arrangements are made for keeping up their high character, so that they may present at the end of the Half-Century every accession to our geographical knowledge. The modes in which they are at present sold are the following: 1. SINGLE MAPS, num bered 1, to 212, plain, 6d. each; coloured, 9d. New plate are being constantly engraved, and others corrected to the present day. 2. COMPLETE ATLAS, with the Index, in the following bindings: 3. LIBRARY ATLAS; containing all the Maps comprised in the first and second volumes of the new issue, with an Index of Places; in half morocco or russia-plain, 51. 58.; coloured 77. 78. 4. FAMILY ATLAS, containing 54 Maps, with an Index to Places. Strongly halfbound morocco, India-rubber backs: price, plain, 27. 2s.; coloured, 27. 16s. 5. CYCLOPÆDIAN ATLAS. The revision of the Geographical Maps of the Society for the Diffusion of Useful Knowledge being now complete, Mr. Knight has issued the GENERAL MAPS, 30 in number, with a COMPLETE INDEX OF NAMES, at a very low price, in Monthly Parts, so as to form a COMPANION ATLAS for the Penny Cyclopædia and the National Cyclopædia. The CYCLOPÆDIAN ATLAS is comprised in TWELVE PARTS, at ONE SHILLING each, PLAIN, and EIGHteenpence ColOURED; each Part containing Two Maps, and a portion of Index, or Three Maps. The work forms a volume strongly bound, plain, 15s.; coloured, 17. 18. 6. SCHOOL ATLAS. Modern.-Comprising 21 Maps, strongly half-bound. Price, plain, 13s. 6d. ; coloured, 19s., or with Index, 4s. additional. Ancient.-18 Maps. Plain, 12s.; coloured, 16s. Ancient and Modern.-Strongly half-bound in one volume. Price, plain, 17. 38. ; coloured, 17. 138. LONDON: CHARLES KNIGHT, 90, FLEET STREET. BEING THE THIRD AFTER BISSEXTILE, OR LEAP YEAR. Price One Shilling, stitched in a wrapper; or, bound in cloth with the Companion to the Almanac, Four Shillings. ALFRED SWEETING, PRINTER, BARTLETT'S BUILDINGS, LONDON.] EXPLANATORY NOTICES. Explanation of the column headed "Thermometrical Register." THE Thermometrical Register commences with Nov. 1849, and closes with Oct. 1850, inclusive. These registers have been carefully copied from those made at the Royal Observatory, Greenwich, and which are also deposited with the Royal Society. They show the highest and lowest ranges within each twenty-four hours, from twelve different readings. Each month is placed with its corresponding month, as affording the most ready and advantageous means of comparison, although by this arrangement the register of the last two months of 1849 follows the ten months of 1850, which are all we can give up to the day of publication. Explanation of the columns headed "Length of day,' ," "Day's increase or decrease," 'Day breaks," and "Twilight ends." 66 THE column headed "Length of day" contains the number of hours and minutes between sunrise and sunset. The column headed "Day's increase expresses the number of hours and minutes which the day has increased since the shortest day; and, where the column is headed "Day's decrease," it expresses the number of hours and minutes which the day has decreased since the longest day; for example, the length of the longest day in 1851 is put down in the column "Length of day" at 16h. 34m.; and on the 6th of July following we find that the length of the day, or the number of hours and minutes between sunrise and sunset, is set down at 16h. 24m.; hence the day has decreased 10m. since the longest day, and, accordingly, in the column " Day's decrease," we find opposite July the 6th Oh. 10m. Equation of Time. In this Almanac the calculations are all made for mean time (given by the clock), instead of apparent time (given by the sun-dial), which latter had been used up to the year 1833. It must be obvious that, for all practical purposes, mean time is the most useful; and to obtain it from apparent time, the columns in the Almanac headed "Equation of Time" should be used. The column "Equation of Time" ought, for example, to be consulted when persons are desirous of setting their clock by a sun-dial. When clock after sun is written above the number of minutes and seconds opposite to the day, then the clock ought to be set so much slower than the sun-dial, and the contrary. Moonlight. THE Moon's age is set down in days and the nearest tenths of days from the time of change. Thus it is New Moon on the 1st of February at 6h. 2m. morning, and there. fore at noon on the 2d she is 1 day 5h. 58m. old, which is set down as 1 day and two. tenths. The fraction of the day of course continues the same throughout the lunation. LIST OF THE CORRESPONDENCE OF ERAS WITH THE YEAR 1851. [In those Eras which begin with the Christian year, the year alone is stated; in those which begin at a different season, the month in which the 1st of January, 1851, occurs is also given.] Roman Year Correspondence 2604 Abbreviations. A.U.C. Year of the World (Constantinopolitan account) Ditto Ditto (Alexandrian account) Egyptian 2597 A. Eg. Julian Period 6564 Jul. Per. Ditto ecclesiastical year.......................................... 12th Kaghots |