keels have, frequently, covered decks, and sometimes carry one mast. These and also the barks are sometimes rowed and sometimes moved up the river by poling, and by drawing them along shore with ropes. The flat boat or ark is of a clumsy construction; but very burthensome. Its foundation consists of sills like those of a house, and to these is trunneled a floor of plank. The sides are of boards loosely put together, and the top is covered in the same way. The bottom of the boat, and so much of the sides as come in contact with the water, are caulked. Some of this kind of boat will carry four or five hundred barrels of flour, besides considerable quantities of bacon, cheese, and other produce. On the deck of the ark are two large oars, moving on pivots, and at the stern there is a large stearing oar. The progress of the ark is principally in floating with the current; and the oars are seldom used excepting for the purpose of rowing ashore.
{154} The business carried on by boats, on the Ohio and Mississippi, is immense. The freight of goods up and down these rivers is high; and the freighting business here is exceedingly profitable. No property pays so great an interest as that of steam boats on these rivers. A trip of a few weeks yields one hundred per cent upon the capital employed.
The arks, and, generally speaking, the keels, when they reach New-Orleans, seldom return up the river again. The former are sold for lumber.
The current of the Ohio is about four miles an hour. That of the Mississippi is rather quicker.
On the river Ohio, nearly opposite to Louisville, there are rapids, the descent of which is about twenty-three feet in the distance of two miles. Owing to this circumstance many boats do not return from below this place. This difficulty, however, is about to be removed by a canal,
