common drink. The tincture of roses to be changed for an emollient gargle.

Fifth day. Three veficles fimilar to the former appeared on her cheft and right arm. Other fymptoms nearly as before. Pulfe not to feeble. Medicines were continued.

Sixth day. Her ftomach rejected the bark. Two new veficles appeared on her neck and cheek. Her breath was fœtid. She had had fome low delirium in the night. Pulfe eighty-eight, and very weak. No fenfe of taite. I prefcribed a decoction of bark, one ounce, in which should be diffolved half a drachm of vegetable alkali, to be taken every two hours; and immediately after each dofe half an ounce of the fame decoction mixed with fix drachms of lemon-juice. Cyder or porter for common drink.

Seventh day. There was little change. The medicines were continued.

Eighth day. The yeficles on the infide of the mouth and on the tongue difappeared, and the cuticle which had been elevated was thrivelled, and of a brownish coJour. Deglutition was difficult, and, as the faid, painful through the whole infide of her throat. Pulfe eighty, and rather ftronger. Bowels regular. Medicines were continued.

Ninth day. The cuticle on the parts formerly occupied by veficles in the infide of the cheek and on the tongue had cracked, and was peeling off: the parts underneath appeared raw and fore. Deglutition had now become fo painful, that the refufed medicine, food, and even drink. She could not

bear the flighteft preffure on the neck. A new veficle appeared under her right ear. Some purulent matter appeared on the back of the pharynx, the origin of which however was not difcernible. Pulfe eighty fix, and of nearly the fame ftrength. I prefcribed a clyfter of warm water after its operation another of new milk and decoction of bark, equal parts: the fame to be repeated four hours afterwards. At night an anodyne clyfter, with fifty drops of thebaic tincture. White liniment for the fores.

Tenth day. The vesicles on the cheft and right arm had disappeared. The fores of the tongue and cheek were of a darker colour, and feemed to be healing. Some new veficles appeared on the abdomen. Pulfe not fo weak. She rested well the former part of the preceding night, but was disturbed by an accident, and afterwards was much inclined to rove in her difcourfe till morning. Medicines were continued.

Eleventh day. The symptoms were nearly the fame as the day before. The veficles on the neck and cheek had disappeared, and the cuticle in thofe parts was thrivelled and cracked. The epigaftric region was extremely fore, and this forenefs much increased by preffure. The laft clyfter of decoction of bark and milk, administered the day before, was not retained. Iordered falep to be fubftituted for milk: other medicines to be continued.

Twelfth day. She could fwallow, though ftill not without pain. I directed the medicines which had been prefcribed the fourth day to be repeated: the others to be omitted.

Thirteenth

Thirteenth day. She vomited fome blood along with the first dofe of the bark. Pulfe eighty, and ftronger. The veficles under the ear and on the abdomen had disappeared. Several fmall veficles (not above the fize of a pea) arofe on the hypogastric region of the abdomen, one on the labia pudendorum, and two on the left thigh. As fhe had taken fome bark which remained on her ftomach, I directed this medicine to be continued, and an anodyne draught to be adminiftered at night.

Fourteenth day. She had two loofe ftools, much intermixed with blood, and complained of great foreness of her belly, increased by preffure. I prefcribed a little caftor oil. Other medicines as before, except the draught.

Fifteenth day. She had had two ftools fomewhat bloody the night before, and one almoft natural in the morning. Pulfe feventy-seven, and of pretty good ftrength. Skin quite cool. Spirits better. And fome little appetite. Menfes had appeared in the morning. I directed the medicines to be continued as before.

From this time the recovered apace, and in about a week had no complaint but weakness. Exercife, however, and the country air, foon completely re-established her health.

After this full ftatement of a cafe very diftinctly marked, it would be fuperfluous to add any thing by way of comment. I have only to obferve, that whether this

diforder be contagious or not, is a question which may poffibly fill admit of fome doubt; though from what I have seen, or been able to collect, I am inclined to think that it is not. Almost all the inftances of this diforder which are precise or well attested I have enumerated; and they are all folitary examples, no two of them having happened at the fame time or place. I fufpect, therefore, that fome other disorders have been oftentimes miftaken for Pemphigus; and that from thence, or from fome preconceived theory, the notion has arisen. When I was affiftant to Dr. Home, in the clinical ward of the infirmary at Edinburgh, a patient was fent to us by Dr. Gregory, whose cafe he fuppofed to be a beginning "Pemphigus," and which he faid was plainly contagious." In a note which he fent with this woman, he fays, "I saw a boy, five "months ago, in the fame close,

*

very ill of the fame disease; and "I am told by the people that fe"veral others, chiefly children,

have had the fame difeafe fince "in the fame clofe." This appeared extremely forcible, and accordingly had its due weight with the ftudents. But in a day or two it appeared very evidently, that the disease of the woman whom Dr. Gregory had fent us, was merely topical. She had no fever. The vehicles (which were fituated under the eye and upon the eye-lid) were of a pale red colour; fome puftules filled with yellow matter appeared upon the brow at the fame time;

and

and both of these vanished almoft immediately after the came into the infirmary; fo that the left it in three or four days perfectly well, having taken no medicine but the faline julep. This woman denied to us that he had ever feen any one affected with vehicles: and upon enquiring more particularly among diferent people in the fame clofe, I found that they were in general very unqualified to give a diftinct account of the epidemic difeafe (whatever it was) with which the children had been affected: they feemed, however, to think it neither novel nor alarming; and by their defcription I fhould rather take it to have been the chickenpox, or fome fuch flight complaint, than the Pemphigus. I can have no doubt that the boy Dr. Gregory mentioned he had feen was really affected with Pemphigus; but I think that the vague teftimony of the ignorant, indifcriminating people of the clofe is to be allowed no Peight in deciding this nice quer

tion.

The nature of this diforder, as to its mildness or malignity, appears to vary confiderably. In fome inftances it is extremely mild, as in three of the cafes I have seen, one of them in this town with Dr. Fleury. In other infances life is in the greatest danger; thus in feveral of the cafes I have enumeratel frong fymptoms of putrefcency were manifefted.

With refpect to the method of cure of this diforder, the general fymptoms of weakness and tendency to putrefaction obviously point out the proper treatment. When the vesicles feize on the internal parts, irritation must be guarded againft by opiates, demulcents, and gentle

An Account of feveral Strata of Earth and Shells on the Banks of York River, in Virginia; of a fubterraneous Paffage, and the judden Defcent of a very large Current of Water from a Mountain, near Carlile, of a remarkably large Spring near Reading, in Pennfylvania; and alfo of several remarkable Springs in the States of Pennfylvania and Virginia. In a Letter from the Hon. Benjamin Lincoln, Efq; F. A, A. to the Rev. Jofeph Willard, V. Pref. A. A. and Prefident of the University at Cambridge. From Memoirs of the American Academy of Arts and Sciences, Vol. I.

T

HAT this earth, fince its

formation, has met with great changes, and that the shores, now covered with the, talleft cedars and most luxuriant plants, were once washed by the ocean, none can deny. The land between James River and York River, in Virginia, is very level; its furface being about forty feet above high-water mark. It appears to have arrived to its prefent height at different periods, far diftant each from the other, by means of the ocean: for near York Town, where the banks are perpendicular, you first see a stratum of earth, about five feet high, intermixed with fmall fhells, which has the appearance of a mixture of clay and land. On that lies, horizontally, a ftratum of white fhells, the cockle, the clam, and others, an

inch or two thick; then a body of earth, fimilar to that first mentioned, eighteen inches thick: and on that lies another thin body of small fhells, then a third body of earth, about the same thickness as the laft; and on that lies another body of white shells, of various kinds, about three feet thick, with very little fand, or earth, mixed with them. On thefe lies a body of oysterfhells, about fix feet thick; then a body of earth to the furface. The oyfter-fhells are fo united by a very ftrong cement, that they fall only when undermined, and then in large bodies, from one to twenty tons weight. They have the appearance of large rocks on the fhores, and are wafted by the frequent wafhing of the fea. All these different ftrata feem to be perfectly horizontal.

After riding about feven miles from York Town, near the center between the two rivers, I difcovered, át a place from which a large body of earth had been removed to a mill-dam, nearly the fame appearance as in the bank firft mentioned.

What they call their ftone, with which they build in York Town, is nothing more than fhells, united by a ftrong cement, which feems to be petrified in a degree, but is apparently affected by the weather.

ON the 2d of Auguft, being at Carlife, in the ftate of Pennfylvania, I went to view a fubterraneous paffage, which had its entrance near a river into a rock. I followed it about two hundred and fifty feet to this distance it was, in general, from fix to feven feet high, and about the fame in width. At the end of two hundred and fifty feet it divided into three branches.-As

they were fmaller, and more difficult to follow, and finding myself exceedingly chilled, (which coft me one of the fickest nights I ever fuffered) I gave up the purfuit, though I had proceeded but about half the diftance, as I was informed by Col. Butler, who had been near the end. It appeared to me that it was a water-courfe, as the rocks were worn smooth, and indented in the manner they ufully are by a long running of water over them. The appearance overhead was curious; fome parts were fmooth like the fides; other parts reprefented various figures, formed by the water which had penetrated through the pores of the rock, and was now petrified and petrifying on its furface. The bottom was apparently earth and finall ftones.

About three years fince, the people in the vicinity of this town, who lived near the mountain, which is about ten miles from the village, were alarmed by a current of water overflowing the banks of the river. The caufe they could not investigate, as there had been, the night before, but a fmall rain: however, they foon found the first effects of the water appeared within about twenty feet of the top of the mountain. Whether it burft forth from the mountain, or was a column of water from the clouds, has not yet been afcertained. The courfe in which it ran down the mountain was dry the next morning. It was confined to the width of twenty feet, perhaps lefs. It appeared to be about thirty feet deep, as could be difcovered by its effects on those trees which were not carried away by the water. It cut a paffage in the fide of the mountain, of about seven or eight feet wide, and near that depth.

The

The traces of it are feen from the town, though, as I faid before, it is ten miles diftant. One rock, of a very confiderable weight, was thrown into the crotch of a tree, twelve feet from the ground, in which it remained for fome time. When the water came into the valley, its impetuofity was fo great that it was not immediately diverted, but reached a fmall rifing ground, through which it cut a paffage; then followed the valley, and fo on to the river, which was at fome confiderable diftance. In its courfe, it carried off all the fences, and came upon the floors of fome of the houfes. I have had fome converfation with Mr. Rittenhouse on the fubject, who has been twice to fee the effects of the water. It is his opinion, that it was not a column of water which burfted forth from the mountain, as it was near the top of one of the highest.

ON my return to Philadelphia, in the neighbourhood of Reading, I came to the greatest spring of water I had ever seen.—It is about fourteen feet deep, and about one hundred feet fquare. A full mill-ftream iffues from it. The water is clear and full of fishes. To account for this body of water, was my enquiry. I foon found, that it was probably the rifing and bursting forth of a very confiderable river, which funk into the ground and totally difappeared, one mile and an half or two miles distant from this place.

In the northern parts of Pennfylvania, there is a creek, called Oil Creek, which empties itself into the Alleghana River, iffuing from a fpring, on the top of which floats an oil, fimilar to what is called Barbadoes tar, and from which may

be collected, by one man, févéral gallons in a day. The troops, ia marching that way, halted at the fpring, collected the oil, and bathed their joints with it. This gave them great relief, and freed them immediately from the rheumatic complaints with which many of them were affected. The troops drank freely of the waters:-they operated as a gentle purge.

There is another spring in the wettern parts of Virginia, as extraordinary in its kind as the one just mentioned, called the Burning Spring. It was known a long time to the hunters. They frequently encamped by it for the fake of obtaining good water. Some of them arrived late one night, and, after making a fire, they took a brand to light them to the fpring. On their coming to it, fome fire dropped from the brand, and in an inftant the water was in a flame, and fo continued, over which they could roaft their meat as foon as by the greatest fire. It was left in this fituation, and continued burning for three months without intermiffion. The fire was extinguifhed by excluding the air from it, or smothering it. The water taken from it into a ves. fel will not burn. This fhews, that the fire is occafioned by nothing more than a vapour that ascends from the waters.

There are two springs high up on the Powtomack; one of which has about the fame degree of heat as blood running from the veins. It is much frequented by people who have loft their health. The waters are drank with freedom, and alfo ferve as a hot bath, by which much' good has been experienced. The other spring, iffuing from the fame mountain, a little further up, is as remarkable