Interesting image illustrating the comparative lengths of Rivers, from Fielding Lucas' New and Elegant Atlas.
Fielding Lucas, Jr. (1781-1854) was a prominent American cartographer, engraver, artist, and public figure during the first half of the 19th century.
Lucas was born in Fredericksburg, Virginia and moved to Philadelphia as a teenager, before settling in Baltimore. There he launched a successful cartographic career. Lucas's first atlas was announced in early- to mid-1812, with production taking place between September 1812 and December of 1813, by which point the engravings were complete. Bound copies of the atlas -- A new and elegant general atlas: Containing maps of each of the United States -- were available early in the next year, beating Carey to market by about two months. Lucas later published A General Atlas Containing Distinct Maps Of all the known Countries in the World in the early 1820s.