a river in Louisiana, which falls into the Mississippi from the west, 195 miles above the mouth of the Ohio, and about 1160 miles from the Belize in the gulf of Mexico. The extent of its navigation is not sufficiently known; but by the map of Captain Hutchins it appears to be navigable 1300 miles. The progress of settlement by the Spaniards on the south and west, and by the English on the north and east, is reported by late travellers to be astonishing; and according to the map of Mr McKenzie, it appears that there is a communication by water, attended with little difficulty, from the upper lakes to Nootka sound, or its vicinity.

In a voyage of discovery undertaken by Captains Lewis and Clarke in 1805, under the auspices of the American government, it appears that the Missouri at the distance of 3848 miles by the course of the river from its junction with the Mississippi, divides into three branches, to which they gave the names of Jefferson's, Madison's, and Gallatin's rivers; and the first of these, Jefferson's river, and the only one explored, is navigable for 248 miles. Phil. Mag. xxvii. 13.