The valleys of these rivers differ from that of the Ohio, not only in having a greater width, but also in being limited on both sides by bluffs stretching along their whole length, and maintaining nearly a parallel direction; whereas the valley of the Ohio is bounded by abrupt hills irregularly disposed, in some instances protruding far into the valley like promontories, and in others retiring from the river, and affording room for bottoms of pretty large extent. The Ohio bottoms are uniformly clad in deep forests, except where they have been removed by settlers; no prairies worthy of notice making their appearance. {208} The valley country, from the circumstances already detailed in allusion to the country constituting the second variety, is almost without exception unhealthy. But at the same time it appears evident, that this evil gradually decreases in proportion to the increase of population, and the consequent advancement of agriculture; for the products of the soil, which the bottoms yield in the greatest profusion, instead of being left to wither and decay upon the surface, are necessarily consumed in the subsistence of man and beast; in consequence of which, one of the most fruitful causes of pestilential effluvia, viz. vegetable putrefaction, is in a very considerable degree removed. The prevailing timber growth of the region comprehending the two sections of country already described, is exhibited in the following list of trees: viz. cotton-wood, willow, sycamore, black walnut, pecan, coffee-tree, sweet and sour or black gum, red and water elm, hackberry, blue and white ash, linden, yellow and white poplar, catalpa, black and honey locust, buck-eye, bur oak, white and black oak, mulberry, box, elder, white dogwood, sugar-tree, white maple, wild cherry, red oak, hickory, iron-wood, and hop hornbeam. The foregoing constitute the principal timber growth of the valley country, and are to be met with more or less frequently throughout the whole of it. Red beech is abundant in some parts of the valley of the Ohio, and in those of many of its tributaries; it abounds also in the northerly parts of the States of Ohio and Indiana. Post oak, black jack, and several other varieties of the oak, also chesnut, white and shell bark, hickory, persimmon, &c. are sometimes found in the bottoms, but are more prevalent upon the hills and highlands. Pitch pine abounds in many parts of Ohio and Indiana, and generally in the neighbourhood of the Alleghany mountains. White pine occasionally {209} makes its appearance in the northerly parts of Ohio. Red cedar is found in a great variety of places throughout the country, but no where in great abundance. The undergrowth of the several tracts of country above considered includes a great variety of shrubs, vines, brambles, grass and other herbage, to be enumerated in a botanical catalogue daily expected from Dr. James.