[1] By the treaty of San Ildefonso, signed the 1st of October 1800. This was never ratified by Charles IV. of Spain, but the treaty of Madrid of the 21st of March 1801, which confirmed it, was signed by him on the 15th of October 1802. LOUISVILLE, the largest city of Kentucky, U.S.A., and the county-seat of Jefferson county, on the Ohio river, 110 m. by rail and 130 m. by water S.W. of Cincinnati. Pop. (1890) 161,129; (1900) 204,731, of whom 21,427 were foreign-born (including 12,383 Germans and 4198 Irish) and 39,139 were negroes; (1910 census) 223,928. Louisville occupies 40 sq. m. of a plain, about 70 sq. m. in extent, about 60 ft. above the low-water mark of the river, and nearly enclosed by hills. The city extends for 8 m. along the river (spanned here by three bridges), which falls 26 ft. in 2 m., but for 6 m. above the rapids spreads out into a beautiful sheet of quiet water about 1 m. wide. The streets intersect at right angles, are from 60 to 120 ft. wide, and are, for the most part, well-shaded. The wholesale district, with its great tobacco warehouses, is largely along Main Street, which runs E. and W. not far from the river; and the heart of the shopping district is along Fourth Street in the dozen blocks S. of Main Street. Adjoining the shopping district on the S. is the old residence section; the newer residences are on "The Highlands" at the E. end and also at the W. end. The city is served by the Baltimore & Ohio South-Western, the Chesapeake & Ohio, the Pittsburg, Cincinnati, Chicago & St Louis, the Louisville, Henderson & St Louis, the Illinois Central, the Chicago, Indiana & Louisville, the Cleveland, Cincinnati, Chicago & St Louis, the Southern and the Louisville & Nashville railways; by steamboat lines to Memphis, Cairo, Evansville, Cincinnati and Pittsburg; by an extensive system of inter-urban electric lines; and by ferries to Jeffersonville and New Albany, Indiana, two attractive residential suburbs.