Biographer and newspaperman Lloyd Lewis accurately portrayed the Mississippi River in the mid-nineteenth century as "The spinal column of America...the symbol of geographic unity." He referred to the great river as "the trunk of the American tree, with limbs and branches reaching to the Alleghenies, the Canadian border, the Rocky Mountains." For more than two thousand miles the river flows silently on its course to the sea, providing a natural artery of commerce. Gliding along the Mississippi's muddy water were steamers and flatboats of all descriptions heavily laden with rich agricultural produce en route to world markets. Indeed, the silent water of the mighty river was the single most important economic feature of the continent, the very lifeblood of America. One contemporary wrote emphatically that "The Valley of the Mississippi is America."

Upon the secession of the Southern states, and in particu-