(Concluded from page 226.) I will conclude this part of the narrative with a brief notice of a few curiosities occurring in the region which has been described. _Caves._ 1. It is well known that it furnishes a great number of interesting _caves_. They are found alike in the inclined and horizontal strata. Some of them are several miles in extent, and afford fine specimens of earthy and alkaline salts. Wier's cave in Virginia has been described by Mr. Kain. I have in my possession a map of its most important apartments, including its whole length, copied from a survey made by Mr. J. Pack in Oct. 1806; also the notes of another survey made in May 1816, by the Rev. Conrad Speece of Augusta county, and Mr. Robert Grattan; which, with an explanation, and particular description, I hope to be able to transmit to you at a future time. From these surveys, it appears that the whole extent of the cave, hitherto discovered, does not exceed eight hundred yards. This was the length stated to me by the guide, when I visited it in August, 1817. I cannot but think there is some mistake in Mr. Kain's remark, that "it is a mile and a half in extent." I spent four hours in examining every accessible part, and by permission of Mr. Henry Bingham, the owner, made a large collection of specimens, which were transmitted for the Cabinet of Yale College.[46] _The Natural Bridge._ 2. My object m naming this celebrated curiosity, is not to give a new description of it, but merely to furnish a correct account of its dimensions. I visited it in company with the Rev. Mr. Huson, who had previously found its height by a cord, to be two hundred and ten feet. We now found it by the quadrant, to be two hundred and eleven feet, and the arch through the centre about forty feet. Some have attempted to account for this great curiosity, by supposing that a convulsion in nature may have rent the hill, in which it stands, asunder; thus forming the deep and narrow defile, over which the rocky strata were left, which constitute its magnificent arch. If so; the sides should have corresponding parts. At a distance from the base, no such correspondence is perceptible. At the base, the rocks are more or less craggy and irregular. This led me to take the courses and distances of each side. The following was the result. Eastern side presents 4 angular points. 1. N. 55° W. 1 chain. 09 links. 2. N. 72 W. 1 ------ 05½ ------ 3. N. 57 W. 1 ------ 12½ ------ 4. N. 50 W. 0 ------ 33 ------ Western side presents 3 angular points. 1. N. 50° W. 0 chain. 45 links. 2. N. 67 W. 1 ------ 12½ ------ 3. N. 77 W. 1 ------ 44 ------ The chain used contained 50 links, equal to 33 feet and ⅓. The distance between the abutments at the north end of their bases, is 80 feet; at the south end, 66 feet. As they ascend, the distance is greater. These data give the following diagram. [Illustration]