A bright, sunny summer morning as ever smiled from the blue heavens, and again I found myself upon the waters. Fast fading in the distance lay the venerable little city of the French, with its ancient edifices and its narrow streets, while in anticipation was a journeying of some hundred miles up the Illinois. Sweeping along past the city and the extended line of steamers at the landing, my attention was arrested by that series of substantial stone mills situated upon the shore immediately above, and a group of swarthy little Tritons disporting themselves in the turbid waters almost beneath our paddle-wheels. Among other singular objects were divers of those nondescript inventions of Captain Shreve, yclept by the boatmen "Uncle Sam's Tooth-pullers;" and, judging from their ferocious physiognomy, and the miracles they have effected in the navigation of the great waters of the West, well do they correspond to the _soubriquet_. {85} The craft consists of two perfect hulls, constructed with a view to great strength; united by heavy beams, and, in those parts most exposed, protected by an armature of iron. The apparatus for eradicating the snags is comprised in a simple wheel and axle, auxiliary to a pair of powerful steam-engines, with the requisite machinery for locomotion, and a massive beam uniting the bows of the hulls, sheathed with iron. The _modus operandi_ in tearing up a snag, or sawyer, or any like obstruction from the bed of the stream, appears to be this: Commencing at some distance below, in order to gain an impetus as powerful as possible, the boat is forced, under a full pressure of steam, against the snag, the head of which, rearing itself above the water, meets the strong transverse beam of which I have spoken, and is immediately elevated a number of feet above the surface. A portion of the log is then severed, and the roots are torn out by the windlass, or application of the main strength of the engines; or, if practicable, the first operation is repeated until the obstacle is completely eradicated. The efficiency of this instrument has been tested by the removal of some thousand obstructions, at an average expense of about twelve or fifteen dollars each.