interpretation of the Federal Constitution; it gave the new republic a grand basis for material greatness; assured its dominance in North America; afforded the field for a magnificent experiment in expansion, and new doctrines of colonization; fed the national land hunger; incidentally moulded the slavery issue; and precipitated its final solution. It is generally agreed that after the Revolution and the Civil War, the Louisiana Purchase is the greatest fact in American history. In 1904 a world's fair, the Louisiana Purchase Exposition, was held at St Louis in commemoration of the cession. After one hundred years the wilderness then acquired had become the centre of the power and wealth of the Union. It contained in 1903 15,000,000 inhabitants, and its taxable wealth alone was four hundred times the fifteen millions given to Napoleon. AUTHORITIES.--The official literature is in the _American State Papers, Foreign Relations_, vol. 2, and _Public Lands_, vol. 2; diplomatic papers reprinted in _House Document 431, 57^th Congress, 2nd Session_ (1903); to which add the _Histoire de la Louisiane et de la cession_ (Paris, 1829; Eng. trans., Philadelphia, 1830), by François Barbé-Marbois. This book abounds in supposed "speeches" of Napoleon, and "sayings" by Napoleon and Livingston that would have been highly prophetic in 1803, though no longer so in 1829. They have been used liberally and indiscriminatingly by the most prominent American historians. See also T. Donaldson, _The Public Domain, House Miscellaneous Document 45, pt. 4, 47^th Congress_, _2nd Session_. For the boundary discussions by J. Q. Adams and Don L. de Onis, 1818-1819, _American State Papers, Foreign Relations_, vol. 4; also in Onis's _Official Correspondence between Don Luis de Onis_ ... _and John Quincy Adams_, &c. (London, 1818), or _Memoria sobre las negociaciones entre España y los Estados Unidos que dieron motivo al tratado de 1819_ (Madrid, 1820). See also discussion and map in _U.S. Census, 1900, Bulletin 74_; and the letters of Thomas Jefferson, James Madison, Rufus King and other statesmen of the time. By far the best general account of the diplomacy is in Henry Adams's _History of the United States_, vols. 1 and 2; and of Western conditions and American sentiment in J. B. McMaster's _History of the United States_, vols. 2 and 3. Consult also Justin Winsor, _Narrative and Critical History_, vol. 7; and various valuable periodical articles, especially in the _American Historical Review_, by F. J. Turner and others. Reference may be made to B. Hermann, _The Louisiana Purchase_ (Washington, 1898), and Theodore Roosevelt's _Winning of the West_, vol. 4. Of the various special but popular accounts (by J. K. Hosmer, Ripley Hitchcock, R. Blanchard, K. E. Winship, &c.), not one is worthy of its subject, and all contain various inaccuracies. FOOTNOTE: