One can hardly pass these broken eminences, with the knowledge that they tally in their calcareous structure and position with the rock formation of the Missouri state border, lying immediately west of them, without regarding them as the apparent monuments of some ancient geological change, which affected a very wide space of country north of their position. A barrier of this nature, which should link the Tennessee and Missouri coasts, at Grand Tower, would have converted into an inland sea the principal area of the present states of Illinois, Indiana, and Southern Ohio. The line of separation in this latitude is not great. It constitutes the narrowest point between the opposing rock formations of the east and west shores, so far as the latter rise through and above the soil. I was still in a floating Monongahela ark as we approached this coast of cliffs. The day was one of the mildest of the month of June, and the surface of the water was so still and calm that it presented the appearance of a perfect mirror. Our captain ordered alongside the skiff, which served as his jolly boat, and directed the men to land me at the Great Cave. Its wide and yawning mouth gave expectations, however, which were not realized. It closes rapidly as it is pursued into the rock, and never could have afforded a safe shelter for gangs of robbers whose haunts were known. Tradition states, on this point, that its mouth was formerly closed and hid by trees and foliage, by which means the unsuspecting voyagers with their upward freight were waylaid. We overtook the slowly floating ark before it had reached Hurricane Island, and the next land we made was at Smithfield, at the mouth of the Cumberland. While here, several discharged Tennessee militiamen, or volunteers from the still unfinished Indian war in the south, landed on their way home. They were equipped after the fashion of western hunters, with hunting shirts and rifles, and took a manifest pride in declaring that they had fought under "old Hickory"--a term which has, since that era, become familiar to the civilized world. I here first saw that singular excrescence in the vegetable kingdom called cypress knees. The point of land between the mouth of the Cumberland and Ohio, was a noted locality of the cypress tree. This tree puts up from its roots a blunt cone, of various size and height, which resembles a sugar loaf. It is smooth, and without limb or foliage. An ordinary cone or knee would measure eight inches in diameter, and thirty inches high. It would seem like an abortive effort of the tree to put up another growth. The paroquet was exceedingly abundant at this place, along the shores, and in the woods. They told me that this bird rested by hooking its upper mandible to a limb. I made several shooting excursions into the neighbouring forests, and remember that I claimed, in addition to smaller trophies of these daily rambles, a shrike and a hystrix.