head, must not be pretermitted. It is on the ascent of a hill, which seems to have been cloven through its length by some great convulsion. The fissure, just at the bridge, is, by some admeasurements, two hundred and seventy feet deep, by others only two hundred and five. It is about forty-five feet wide at the bottom and ninety feet at the top; this of course determines the length of the bridge, and its height from the water. Its breadth in the middle is about sixty feet, but more at the ends, and the thickness of the mass, at the summit of the arch, about forty feet. A part of this thickness is constituted by a coat of earth, which gives growth to many large trees. The residue, with the hill on both sides, is one solid rock of lime-stone. The arch approaches the semi-elliptical form; but the larger axis of the ellipsis, which would be the cord of the arch, is many times longer than the transverse. Though the sides of this bridge are provided in some parts with a parapet of fixed rocks, yet few men have resolution to walk to them, and look over into the abyss. You involuntarily fall on your hands and feet, creep to the parapet, and peep over it. Looking down from this height about a minute, gave me a violent head-ache. If the view from the top be painful and intolerable, that from below is delightful in an equal extreme. It is impossible for the emotions arising from the sublime to be felt beyond what they are here; so beautiful an arch, so elevated, so light, and springing as it were up to heaven! The

rapture of the spectator is really indescribable! The fissure continuing narrow, deep, and straight, for a considerable distance above and below the bridge, opens a short but very pleasing view of the North. mountain on one side and the Blue Ridge on the other, at the distance each of them of about five miles. This bridge is in the county of Rockbridge, to which it has given name, and affords a public and commodious passage over a valley which cannot be crossed elsewhere for a considerable distance. The stream passing under it is called Cedar creek. It is a water of James' river, and sufficient in the driest seasons to turn a grist-mill, though its fountain is not more than two miles above.1

Don Ulloa mentions a break, similar to this, in the province of Angaraez, in South America. It is from sixteen to twenty-two feet wide, one hundred and eleven feet deep, and of 1.3 miles continuance, English measure. Its breadth at top is not sensibly greater than at bottom. But the following fact is remarkable, and will furnish some light for conjecturing the probable origin of our natural bridge. “Esta caxa, ó cauce está cortada en péna viva con tanta precision, que las desigualdades del un lado entrantes, corresponden á las del otro lado salientes, como si aquella altura se hubiese abierto expresamente, con sus bueltas y tortuosidades, para darle transito á los aguas por entre los dos morallones que la forman; siendo tal su igualdad, que si llegasen á juntarse se endentarian uno con otro sin dextar hueco." Not. Amer. ii. 10. Don Ulloa inclines to the opinion that this channel has been effected by the wearing of the water which runs through it, rather than that the mountain should have been broken open by any convulsion of nature. But if it had been worn by the running of water, would not the rocks which form the sides, have been worn plain? or if, meeting in some parts with veins of harder stone, the water had left prominences on the one side, would not the same cause have sometimes, or perhaps generally, occasioned prominences on the other side also? Yet Don Ulloa tells us, that on the other side there are always corresponding cavities, and that these tally with the prominences so per

QUERY VI.

A notice of the mines and other subterraneous riches; its trees, plants, fruits, etc.

I knew a single instance of gold found in this State. It was interspersed in small specks through a lump of ore of about four pounds weight, which yielded seventeen pennyweights of gold, of extraordinary ductility. This ore was found on the north side of Rappahanoc, about four miles below the falls. I never heard of any other indication of gold in its neighborhood.

On the Great Kanhaway, opposite to the mouth of Cripple creek, and about twenty-five miles from our southern boundary, in the county of Montgomery, are mines of lead. The metal is mixed, sometimes with earth, and sometimes with rock, which requires the force of gunpowder to open it; and is accompanied with a portion of silver too small to be worth separation under any process hitherto attempted there. The proportion yielded is from fifty to eighty pounds of pure metal from one hun

fectly, that, were the two sides to come together they would fit in all their indentures, without leaving any void. I think that this does not resemble the effect of running water, but looks rather as if the two sides had parted asunder. The sides of the break, over which is the natural bridge of Virginia, consisting of a veiny rock which yields to time, the correspondence between the salient and re-entering inequalities, if it existed at all, has now disappeared. This break has the advantage of the one described by Don Ulloa in its finest circumstance; no portion in that instance having held together, during the separation of the other parts, so as to form a bridge over the abyss.

VOL 11-3

dred pounds of washed ore. The most common is that of sixty to one hundred pounds. The veins are sometimes most flattering, at others they disappear suddenly and totally. They enter the side of the hill and proceed horizontally. Two of them are wrought at present by the public, the best of which is one hundred yards under the hill. These would employ about fifty laborers to advantage. We have not, however, more than thirty generally, and these cultivate their own corn. They have produced sixty tons of lead in the year; but the general quantity is from twenty to twenty-five tons. The present furnace is a mile from the ore bank and on the opposite side of the river. The ore is first wagoned to the river, a quarter of a mile, then laden on board of canoes and carried across the river, which is there about two hundred yards wide, and then again taken into wagons and carried to the furnace. This mode was originally adopted that they might avail themselves of a good situation on a creek for a pounding mill; but it would be easy to have the furnace and pounding mill on the same side of the river, which would yield water, without any dam, by a canal of about half a mile in length. From the furnace the lead is transported one hundred and thirty miles along a good road, leading through the peaks of Otter to Lynch's ferry, or Winston's on James' river, from whence it is carried by water about the same distance to Westham. This land carriage may be greatly shortened, by delivering the