bridge, are people who have passed their lives within half a dozen miles, and have never been to survey these monuments of a war between rivers and mountains which must have shaken the earth itself to its centre.'-The height of our mountains has not yet been [32] estimated with any degree of exactness. The Alleghaney being the great ridge which divides the waters of the Atlantic from those of the Missisipi, its summit is doubtless more elevated above the ocean than that of any other mountain. But its relative height, compared with the base on which it stands, is "The reflections I was led into on viewing this passage of the Potowmac thro' the Blue ridge were, that this country must have suffered some violent convulsion, and that the face of it must have been changed from what it probably was some centuries ago; that the broken and ragged faces of the mountain on each side the river; the tremendous rocks, which are left with one end fixed in the precipice, and the other jutting out, and seemingly ready to fall for want of support, the bed of the river for several miles below obstructed, and filled with the loose stones carried from this mound; in short, everything on which you cast your eye evidently demonstrates a disrupture and breach in the mountain, and that, before this happened, what is now a fruitful vale, was formerly a great lake or collection of water, which possibly might have here formed a mighty cascade, or had its vent to the ocean by the Susquehanna, where the Blue ridge seems to terminate. Besides this, there are other parts of this country which bear evident traces of a like convulsion. From the best accounts I have been able to obtain, the place where the Delaware now flows through the Kittatinny mountain, which is a continuation of what is called the North ridge, or mountain, was not its original course, but that it passed through what is now called “the Wind-gap," a place several miles to the westward, and about a hundred feet higher than the present bed of the river. This Wind-gap is about a mile broad, and the stones in it such as seem to have been washed for ages by water running over them. Should this have been the case, there must have been a large lake behind that mountain, and by some uncommon swell in the waters, or by some convulsion of nature, the river must have opened its way through a different part of the mountain, and meeting there with less obstruction, carried away with it the opposing mounds of earth, and deluged the country below with the immense collection of waters to which this new passage gave vent. There are still remaining, and daily discovered, innumerable instances of such a deluge on both sides of the river, after it passed the hills above the falls of Trenton, and reached the Champaign. On the New Jersey side, which is flatter than the Pennsylvania side, all the country below Croswick hills seems to have been overflowed to the distance of from ten to fifteen miles back from the river, and to have acquired a new soil by the earth and clay brought down and mixed with the native sand. The spot on which Philadelphia stands evidently appears to not so great as that of some others, the country rising behind the successive ridges like the steps of stairs. The mountains of the Blue ridge, and of these the Peaks of Otter, are thought to be of a greater height, measured from their base, than any others in our country, and perhaps in North America. From data, which may found a tolerable conjecture, we suppose the highest peak to be about 4000 feet perpendicular, which is not a fifth part of the height of the mountains of South America,' nor one third of the height which would be necessary in our latitude to preserve ice be made ground. The different strata through which they pass in digging to water, the acorns, leaves, and sometimes branches, which are found above twenty feet below the surface, all seem to demonstrate this. I am informed that at Yorktown in Virginia, in the bank of York river, there are different strata of shells and earth, one above another, which seem to point out that the country there has undergone several changes; that the sea has, for a succession of ages, occupied the place where dry land now appears; and that the ground has been suddenly raised at various periods. What a change would it make in the country below, should the mountains at Niagara, by any accident, be cleft asunder, and a passage suddenly opened to drain off the waters of Erie and the upper lakes! While ruminating on these subjects, I have often been hurried away by fancy, and led to imagine, that what is now the bay of Mexico, was once a champaign country; and that from the point or cape of Florida, there was a continued range of mountains through Cuba, Hispaniola, Porto Rico, Martinique, Guadaloupe, Barbadoes, and Trinidad, till it reached the coast of America, and formed the shores which bounded the ocean, and guarded the country behind; that by some convulsion or shock of nature, the sea had broken through these mounds, and deluged that vast plain, till it reached the foot of the Andes; that being there heaped up by the trade winds, always blowing from one quarter, it had found its way back, as it continues to do, through the Gulf between Florida and Cuba, carrying with it the loam and sand it may have scooped from the country it had occupied, part of which it may have deposited on the shores of North America, and with part formed the banks of Newfoundland. But these are only the visions of fancy."-Charles Thomson, in appendix. In the edition of 1853 is added the following footnote: "Herodutus, 1. 7, c. 129, after stating that Thessaly is a plain country surrounded by high mountains, from which there is no outlet but the fissure through which the Peneus flows, and that according to ancient tradition it had once been an entire lake, supposes that fissure to have been made by an earthquake rending the mountain asunder." In the edition of 1853 are footnote references as follows: "1. Epoques, 434. Musschenbroek, $2,312. 2. Epoques, 317." in the open air unmelted through the year. The ridge of moun tains next beyond the Blue ridge, called by us the North mountain, is of the greatest extent; for which reason they were named by the Indians the Endless mountains.' [33] A substance supposed to be Pumice, found floating on the Missisipi, has induced a conjecture that there is a volcano on some of its waters; and as these are mostly known to their sources, except the Missouri, our expectations of verifying the conjecture would of course be led to the mountains which divide 1 In the edition of 1853, the following addition is here inserted: "To what is here said on the height of mountains, subsequent information has enabled me to furnish some additions and corrections. "General Williams, a nephew of Dr. Franklin, on a journey from Richmond by the warm and Red Springs to the Alleghaney, has estimated by barometrical observations the height of some of our ridges of mountains above the tide-water as follows: The Eastern base of the Blue Ridge subjacent to Rockfish Gap, feet 100 1,822 The valley constituting the Eastern basis of the Warm Spring Mountain, 943 2,247 The Western valley of the Warm Spring Mountain, being the Eastern base of the Alleghaney, 949 Summit of the Alleghaney, 6 miles Southwest of the Red Springs, "In November, 1815, with a Ramsden's theodolite of 31⁄2 inches radius, with nonius divisions to 3', and a base of 1/4 mile on the low grounds of Otter River, distant 4 miles from the summits of the two peaks of Otter, I measured geometrically their heights above the water of the river at its base, and found that of the sharp or South peak, That of the flat or North peak, 2,760 2,946 3,103/2 As we may with confidence say that the base of the peaks is at least as high above the tide-water at Richmond as that of the Blue Ridge at Rockfish Gap, (being 40 miles farther westward,) and their highest summit of course 3,2031⁄2 feet above that tide-water, it follows that the summit of the highest peak is 3431⁄2 feet higher than that of the Alleghaney, as measured by General Williams. "The highest of the White Mountains in New Hampshire, by barometrical estimate made by Captain Partridge, was found to be 4,885 feet from its base, and the highest of the Catskill mountains in New York 3,105 feet. "Two observations, with an excellent pocket sextant, gave a mean of 37° 28' 50" for the latitude of the sharp peak of Otter. "Baron Humboldt states that in latitude 37° (which is nearly over medium parallel,) perpetual snow is no where known so low as 1,200 toises = 7,671 feet above the level of the sea, and in sesquialtoral ratio nearly to the highest peak of Otter." the waters of the Mexican Gulph from those of the South sea; but no volcano having ever yet been known at such a distance from the sea, we must rather suppose that this floating substance has been erroneously deemed Pumice.' QUERY V. Its cascades and caverns? The only remarkable Cascade in this country is that of the Falling Spring in Augusta. It is a water of James river where it is called Jackson's river, rising in the warm spring mountains, about twenty miles South West of the warm spring, and flowing into' that valley. About three quarters of a mile from its source it falls over a rock 200 feet into the valley below. The sheet of water is broken [34] in its breadth by the rock, in two or three places, but not at all in its height. Between the sheet and the rock, at the bottom, you may walk across dry. This Cataract will bear no comparison with that of Niagara as to the quantity of water composing it; the sheet being only 12 or 15 feet wide above, and somewhat more spread below; but it is half as high again, the latter being only 156 feet, according to the mensuration made by order of M. Vaudreuil, Governor of Canada, and 130 according to a more recent account. In the limestone country there are many caverns of very considerable extent. The most noted is called Madison's Cave, and is on the North side of the Blue ridge, near the intersection of the Rockingham and Augusta line with the south fork of the southern river of Shenandoah. It is in a hill of about 200 feet perpendicular height, the ascent of which, on one side, is so steep, that you may pitch a biscuit from its summit into the river 'In the edition of 1853 is a footnote reference to 2 Epoques, 91, 112." 2 In edition of 1853 is the following footnote: 'Bouguer mentions a cascade of two or three hundred toises height of the Bogota, a considerable river passing Santa Fé. The cataract is verticle, and is about 15 or 16 leagues below Santa Fe.-Bouguer, xci. Buffon mentions one of 300 feet at Terni, in Italy. 1. Epoques, 470." 3 Altered in edition of 1853 to "and flowing from that valley." the termination you ascend by asmall a -plored1 mile. Salt Petr is room Note. The principal cave is from 50 to 80Ptwide,&about Uncxploria eSpring A large quantity of excellent Salt Petre denotes the commencement &termination of the Glauber Salts Sick room, not explored more than 4 mile Haunted Roo Tara with very little stone Claystrongly impregnated with from the mouth you descent by a narrow winding Chasm 30ft & intera nitre from 6 to 10 A dep Explored 2 Miles at this distance spacious cave, running in a direction parrallel with the haunted room & as it is supposed, directly underit. This lowercave has been explored one Mile Clay strongly impregnated with nitre, kin great abundance. Largespring falling into a well, at least 30 deep. Spring |