earth: but most of them are variegated with red, blue, and purple. None of it has been ever worked. It forms a very large precipice, which hangs over a navigable part of the river. It is faid there is marble at Kentucky. • But one vein of lime-ftone is known below the Blue Ridge. Its first appearance, in our country, is in Prince William, two miles below the Pignut Ridge of mountains; thence it paffes on nearly parallel with that, and croffes the Rivannna about five miles below it, where it is called the Southwest Ridge. It then croffes Hardware, above the mouth of Hudfon's creek, James river at the mouth of Rockfish, at the marble quarry before fpoken of, probably runs up that river to where it appears again at Rofs's iron-wo ks, and fo paffes off fouth-weftwardly by Flat creek of Otter river. It is never more than 100 yards wide. From the Blue Ridge weftwardly the whole country feems to be founded on a rock of limeftone, befides infinite quantities on the furface, both loofe and fixed. This is cut into beds, which range, as the mountains and fea-coaft do, from fouth-weit to north-eaft, the lamina of each bed declining from the horizon towards a parellelifm with the axis of the earth. Being ftruck with this obfervation, I made, with a quadrant, a great number of trials on the angles of their declination, and found them to vary from 22° to 60°, but avaraging all my trials, the refult was within one-third of a degree of the elevation of the pole or latitude of the place, and much the greatest part of them taken separately were little different from that: by which it appears, that these lamina are, in the main, parallel with the axis of the earth. fome inftances, indeed, I found them perpendicular, and even reclining the other way but these were extremely rare, and always attended with figns of convulfion, or other circumftances of fingularity, which admitted a poffibility of removal from their original pofition. These trials were made between Madison's cave and the Patomak. We hear of lime-ftone on the Millifippi and Ohio, and in all the mountainous country between the eastern and wettern waters, not on the mountains themselves, but occupying the valleys between them. In Near the western foot of the North Mountains are immenfe bodies of Schift, containing impreffion of fhells in a variety of forms. I have received petrified Thells of very different kinds from the first fources of the Kentucky, which bear no refemblance to any I have ever seen on the tidewaters. It is faid that shells are found in the Andes, in South-America, 15,000 feet above the level of the ocean. Medicinal Springs.] There are several medicinal springs, fome of which are indubitably efficacious, while others feem to owe their reputation as much to fancy, and change of air and regimen, as to their real virtues. None of them having undergone a chymical analyfis in fkilful hands, nor been fo far the fubject of obfervation as to have produced a reduction into claffes of the diforders which they relieve, it is in my power to give little more than an enumeration of them. • The most efficacious of thefe are two fprings in Augufta, near the firft fources of James river, where it is called Jackfon's river. They rife near the foot of the ridge of mountains generally called the Warm Spring mountain, but in the maps Jackfon's mountains. The one is dif tinguished by the name of the Warm Spring, and the other of the Hot Bb z Spring. Spring. The Warm Spring iffues with a very bold ftream, fufficient to work a grift-mill, and to keep the waters of its bafon, which is 30 feet in diameter, at the vital warmth, viz. 96° of Farenheit's thermometer. The matter with which these waters is allied is very volatile; its fmell indicates it to be fulphureous, as alfo does the circumftance of turning filver black. They relieve rheumatisms. Other complaints also of very different natures have been removed or leffened by them. It rains here four or five days in every week. The Hot Spring is about fix miles from the Warm, is much smaller, and has been fo hot as to have boiled an egg. Some believe its degree of heat to be leffened, It raifes the mercury in Farenheit's thermometer to 112 degrees, which is fever heat. It fometimes relieves where the Warm Spring fails. A fountain of common water, iffuing within a few inches of its margin, gives it a fingular appearance. Comparing the temperature of these with that of the hot fprings of Kamschatka, of which Krachininnikow gives an account, the difference is very great, the latter raising the mercury to 200°, which is within 12° of boiling water. These springs are very much resorted to in spite of a total want of accommodation for the fick. Their waters are ftrongest in the hottest months, which occafions their being visited in July and Auguft principally. The fweet fprings are in the county of Botetourt, at the eastern foot of the Allegany, about 42 miles from the warm fprings. They are ftill lefs known. Having been found to relieve cafes in which the others had been ineffectually tried, it is probable their compofition is different. They are different alfo in their temperature, being as cold as common water: which is not mentioned, however, as a proof of a distinct impregnation. This is among the first fources of James river. • On Patomak river, in Berkeley county, about the North mountain, are medicinal springs, much more frequented than thofe of Augufta. Their powers, however, are lefs, the water weakly mineralized, and fcarcely warm. They are more vifited, because fituated in a fertile, plentiful, and populous country, better provided with accommodations, always fafe from the Indians, and neareft to the more populous ftates. In Louifa county, on the head waters of the South Anna branch of York river, are springs of fome medicinal virtue. They are not much ufed, however. There is a weak chalybeate at Richmond; and many others in various parts of the country, which are of too little worth, or too little note to be enumerated after thofe before-mentioned. We are told of a Sulphur Spring on Howard's creek of Green Briar, and another at Boonfborough on Kentucky. In the low grounds of the Great Kanhaway, 7 miles above the mouth of Elk River, and 67 above that of the Kanhaway itself, is a hole in the earth of the capacity of 30 or 40 gallons, from which iffues conftantly a bituminous vapour in fo ftrong a current, as to give to the fand about its orifice the motion which it has in a boiling fpring. On prefenting a lighted candle or torch within 18 inches of the hole, it flames up in a column of 18 inches diameter, and four or five feet in height, which fometimes burns out within 20 minutes, and at other times has been known to continue three days, and then has been left ftill burning. The flame is unsteady, of the density of that of burning fpirits, and fmells like burning pit coal. Water fometimes collects in the bafon, which is remarkably cold, and is kept in ebullition by the vapour iffuing through it. If the vapour be fired in that ftate, the water foon becomes fo warm that the hand cannot bear it, and evaporates wholly in a fhort time. This, with the circumjacent lands, is the property of his Excellency General Washington and of General Lewis. There is a fimilar one on Sandy river, the flame of which is a column of about 12 inches diameter, and 3 feet high. General Clark, who informs me of it, kindled the vapour, ftaid about an hour, and left it burning. The mention of uncommon fprings leads me to that of Syphon fountains. There is one of these near the interfection of the lord Fairfax's boundary with the North mountain, not far from Brock's gap, on the ftream of which is a grift-mill, which grinds two bushels of grain at every flood of the fpring. Another near the Cow-pafture river, a mile and a half below its confluence with the Bull-pafture river, and 16 or 17 miles from the Hot-Springs, which intermits one in every twelve hours. alfo near the mouth of the North Holfton. One After thefe may be mentioned the Natural Well, on the lands of a Mr. Lewis in Frederick county. It is somewhat larger than a common well: the water rifes in it as near the furface of the earth as in the neighbouring artificial wells, and is of a depth as yet unknown. It is faid there is a current in it tending fenfibly downwards. If this be true, it probably feeds fome fountain, of which it is the natural refervoir, distinguished from others, like that of Madison's cave, by being acceffible. It is used with a bucket and windlass as an ordinary well. Population. Population.] The following table fhews the number of perfons imported for the establishment of our colony in its infant ftate, and the cenfus of inhabitants at different periods, extracted from our historians and public records, as particularly as I have had opportunities and leisure to examine them. Succeffive lines in the fame year fhew fucceffive periods of time in that year. I have ftated the cenfus in two different columns, the whole inhabitants having been fometimes numbered, and fometimes the tythes only. This term, with us, includes the free males above 16 years of age, and flaves above that age of both fexes. TABL E. Settlers Cenfus of Settlers Cenfus of Cenfus of Year imported. Inhabitants. Years imported. Inhabitants. Tythes. A further examination of our records would render this history of our polation much more fatisfactory and perfect, by furnishing a greater unmber number of intermediate terms. Thefe however which are here ftated will enable us to calculate, with a confiderable degree of precifion, the rate at which we have increased. During the infancy of the colony, while numbers were fmall, wars, importations, and other accidental cir cumstances, render the progreffion fluctuating and irregular. By the year 1654. however, it becomes tolerably uniform, importations having in a great measure ceafed from the diffolution of the company, and the inhabitants become too numerous to be fenfibly affected by Indian wars. Beginning at that period, therefore, we find that from thence to the year 1772, our tythes had increafed form 7209 to 153,000. The whole term being of 118 years, yields a duplication once in every 274 years. The intermediate enumerations taken in 1700, 1748, and 1759, furnish proofs of the uniformity of this progreffion. Should this rate of increase continue, we fhall have between fix and feven millions of inhabitants within 95 years. If we fuppofe our country to be bounded, at fome future day', by the meridian of the mouth of the Great Kanhaway, (within which it has been before conjectured are 64,491 fquare miles) there will then be 100 inhabitants for every fquare mile, which is nearly the ftate of population in the British iflands. Here I will beg leave to propofe a doubt. The prefent defire of America is to produce rapid population by as great importations of foreigners as poffible. But is this founded in good policy? The advantage propofed is the multiplication of numbers. Now let us fuppofe (for example only) that in this ftate, we could double our numbers in one year by the importation of foreigners; and this is a greater acceffion than the moft fanguine advocate for emigration has a right to expect. Then I fay, beginning with a double ftock, we shall attain any given degree of population only 27 years and 3 months fooner, than if we proceed on our fingle ftock. If we propose 4,500,000 as a competent population for this ftate, we fhould be 54 years attaining it, could we at once double our numbers; and 813 years, if we rely on natural propagation, as may be feen by the following table, TABLE. Proceeding on a double ftock. In the first column are ftated periods of 27 years; in the fecond are our numbers, at each period, as they will be if we proceed on our actual ftock; and in the third are what they would be, at the fame periods, were we to fet out from the double of our prefent ftock. I have taken the term of 4,500,000 inhabitants for example's fake only. Yet I am perfuaded it is a greater number than the country fpoken of, confidering how much inarable land it contains, can clothe and feed without a mate |