HALF A CENTURY OF THE BRITISH EMPIRE.--A History of the Kingdom and the People from 1800 to 1850. By HARRIET MARTINEAU, Part I., price 1s., with Portraits of PITT, FOX, NELSON and NAPOLEON. The Work will be completed in Twenty-four Shilling Parts, published twice a month. THE NATIONAL CYCLOPAEDIA OF USEFUL KNOWLEDGE. Part XLVIII., First half, price 6d. The Second Half-part. price 6d., completing the Work, will be published in March, 1851. KNIGHT'S CYCLOPAEDIA OF THE INDUSTRY OF ALL NATIONS. Part III., price 9d. Issued also in Weekly Numbers, price 2d. KNIGHT'S CYCLOPAEDIA OF LONDON. Part III., price 9d. Issued also in Weekly Numbers, price 2d. KNIGHT'S EXCURSION TRAIN COMPANION. Part I., price 9d. Issued also in Weekly Numbers, price 2d. HALF-HOURS WITH THE BEST AUTHORS. Part XI., price 6d. Issued also in Weekly Numbers, price 11/2d. HALF-HOURS WITH THE BEST AUTHORS. Volume III., with Portraits on Steel of SCOTT, BYRON, COWPER, and WORDSWORTH, handsomely bound in cloth, price 2s. 6d. Vols. I and II., uniformly bound, are constantly on sale. PICTORIAL HALF-HOURS; or MISCELLANIES OF ART. Part IX., price 9d. Issued also in Weekly Numbers, price 2d. each. [***] The First and Second Volumes, with illuminated Frontispieces, handsomely bound in cloth, price 3s. 6d. each, are constantly on sale. THE LAND WE LIVE IN. PART XXXIX., price 1s. containing SOUTH WALES, with a Map, and numerous Woodcuts. * * * * * DESCRIPTIVE CATALOGUES of Mr. CHARLES KNIGHT'S PUBLICATIONS may be had on Application. * * * * * London: CHARLES KNIGHT, 90. Fleet Street. * * * * * Printed by THOMAS CLARK SHAW, of No. 8. New Street Square, at No. 5. New Street Square, in the Parish of St. Bride in the City of London; and published by GEORGE BELL, of No. 186. Fleet Street, in the Parish of St Dunstan in the West, in the City of London, Publisher, at No. 186, Fleet Street aforesaid.--Saturday, February 1. 1851.