AFTER remaining a considerable time in Bottetourt County, I again crossed Fluvanna River into the county of Rockbridge, so called from the remarkable natural bridge of rock that is in it. This bridge stands about ten miles from Fluvanna River, and nearly the same distance from the Blue Ridge. It extends across a deep cleft in a mountain, which, by some great convulsion of nature, has been split asunder from top to bottom, and it seems to have been left there purposely to afford a passage from one side of the chasm to the other. The cleft or chasm is about two miles long, and is in some places upwards of three hundred feet deep; the depth varies according to the height of the mountain, being deepest where the mountain is most lofty. The breadth of the chasm also varies in different places; but in every part it is uniformly wider at top than towards the bottom. That the two sides of the chasm were once united appears very evident, not only from projecting rocks on the one side corresponding with suitable cavities on the other, but also from the different strata of earth, sand, clay, &c. being exactly similar from top to bottom on both sides; but by what great agent they were separated, whether by fire or by water, remains hidden amongst those arcana of nature which we vainly endeavour to develope. [Sidenote: ROCK BRIDGE.] The arch consists of a solid mass of stone, or of several stones cemented so strongly together, that they appear but as one. This mass, it is to be supposed, at the time that the hill was rent asunder, was drawn across the fissure from adhering closely to one side, and being loosened from its bed of earth at the opposite one. It seems as probable, I think, that the mass of stone forming the arch was thus forcibly plucked from one side, and drawn across the fissure, as that the hill should have remained disunited at this one spot from top to bottom, and that a passage should afterwards have been forced through it by water. The road leading to the bridge runs through a thick wood, and up a hill, having ascended which, nearly to the top, you pause for a moment at finding a sudden discontinuance of the trees at one side; but the amazement which fills the mind is great indeed, when, on going a few paces towards the part which appears thus open, you find yourself on the brink of a tremendous precipice. You involuntarily draw back, stare around, then again come forward to satisfy yourself that what you have seen is real, and not the illusions of fancy. You now perceive, that you are upon the top of the bridge, to the very edge of which, on one side, you may approach with safety, and look down into the abyss, being protected from falling by a parapet of fixed rocks. The walls, as it were, of the bridge at this side are so perpendicular, that a person leaning over the parapet of rock might let fall a plummet from the hand to the very bottom of the chasm. On the opposite side this is not the