But a very few years have passed away since the navigation of the Mississippi was that of one of the most dangerous streams on the globe; but, thanks to the enterprising genius of the scientific Shreve, this may no longer with truth be said. In 1824 the first appropriation[57] was voted by Congress for improving the navigation of the Western rivers; and since that period thousands of snags, sawyers, {64} planters, sand-bars, sunken rocks, and fallen trees have been removed, until all that now remains is to prevent new obstacles from accumulating where the old have been eradicated. For much of its course in its lower sections, the Mississippi is now quite safe; and as the progress of settlements advances upon its banks, the navigation of this noble stream will doubtless become unobstructed in its whole magnificent journey from the falls of the "Laughing Water" to the Mexican Gulf. The indefatigable industry, the tireless perseverance, the indomitable enterprise, and the enlarged and scientific policy of Captain Shreve, the projector and accomplisher of the grand national operations upon the Western rivers, can never be estimated beyond their merit. The execution of that gigantic undertaking, the removal of the Red River Raft, has identified his history with that of the empire West;[58] his fame will endure so long as those magnificent streams, with which his name is associated, shall continue to roll on their volumed waters to the deep. These remarks have been suggested by scenes of constant recurrence to the traveller on the Mississippi. The banks, the forests, the islands all differ as much as the stream itself from those of the soft-gliding Ohio. Instead of those dense emerald masses of billowy foliage swelling gracefully up from the banks of "the beautiful river," those of the Mississippi throw back a rough, ragged outline; their sands piled with logs and uprooted trees, while heaps of wreck and drift-wood betray the wild ravages of the stream. In the midst of {65} the mass a single enormous sycamore often rears its ghastly limbs, while at its foot springs gracefully up a light fringe of the pensile willow. Sometimes, too, a huge sawyer, clinging upon the verge of the channel, heaves up its black mass above the surface, then falls, and again rises with the rush of the current. Against one of these sawyers is sometimes lodged a mass of drift-wood, pressing it firmly upon the bottom, till, by a constant accumulation, a foundation is gradually laid and a new island is formed: this again, by throwing the water from its course, causes a new channel, which, infringing with violence upon the opposite bank, undermines it with its colonnade of enormous trees, and thus new material in endless succession is afforded for obstructions to the navigation. The deposites of alluvion along the banks betray a similar origin of gradual accumulation by the annual floods. In some sections of the American Bottom,[59] commencing at its