There are a number of round ftones, thrown to the diftance of half a mile from the hill, that seem to have felt the force of fire to a confiderable degree: these, I suppose, were thrown out of the hill, by the violence of the erupti

on.

It is the opinion of fome, that the hill has burfted twice; and that, the second time, it did not run with melted matter, as at the firft eruption; but only threw out the large lumps of lava, which appear on the top of the ground. I remain, Sir,

With great respect,

Yours, &c. T. D.

Additional remarks on the fame fubject, by the author of the foregoing account: addreffed to DR. GREENWAY.

Read Feb. 19, 1790.

HE crater is nearly filled up, and covered

TH

with large trees: one fide still fhews the hollow appearance of a crater.

The lava covers the top in many places, but in others the congealed lava has been thrown out in large pieces around the hill, which feems to be done by an eruption fubfequent to the melting and boiling. Pieces, weighing one thousand pounds or more, lie around the hill; fome near, others more diftant.

The ftream of lava terminates within twenty yards of a creek and is nearly uniform in thicknefs, without any large ftones, toward the end, but only gravel congealed

in it.

The mouldered lava is of the colour of rufty iron, and is covered with a rich mould of fix inches, of a different appearance, and the fame as covers the adjacent ground.

It

It appears that this covering of mould has been laid upon the lava by inundations of the river. The mouldered part of the ftream of lava is, in many places, ploughed up, and feems to moulder and crumble away much fafter when thus exposed to the air.

The lava has iron in its compofition, and when pulverized is attracted by the magnet; and wherever a pebble-ftone is ftruck out from it, there remains a cavity, greatly resembling a cast iron veffel: fo that this congealed matter must have sustained a great degree of fire to keep it in a state of liquefaction, boiling and running over the top of the volcano, in a ftream of liquid fire, for half a mile, on the level ground, before it congealed. After fubjecting it to the magnet, as mentioned above, we fubmitted it to the crucible, where it melted and ran as we are told the lava of Etna does.

Farther remarks: extracted from a letter from DR. GREENWAY to DR. BARTON.

Read May, 18, 1792.

T

HE gentleman who examined this extinguished volcano, and furnished me with his defcription of it, has fince brought me a piece of the lava, of which, he fays, there are coagulated maffes, on the fummit of the hill, that will weigh a thousand or fifteen hundred pounds. It is compofed of earth, common pebble-ftones, fome metallic fubftance, particularly iron attracted by the magnet; and the whole melts into a confufed liquid mass in a crucible placed in the heat of a common smith's furnace.

VOL. III.

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No. XXIX.

No. XXIX.

An account of a poisonous plant, growing Spontaneously in the fouthern part of Virginia. Extracted from a paper, by Dr. James Greenway, of Dinwiddie-County, in Virginia.

Read Feb. 19, 1790.

T

O point out an article of the creation, fraught with noxious qualities, dangerous to mankind, and hurtful to animals, is equally as ferviceable to the public, as to inform them of the medicinal virtues of the most falutary vegetable, or celebrated antidote.

As the virtues of plants have been generally difcovered, by accident; fo likewife have deleterious qualities been detected, in others, where no fufpicion had ever been entertained of fuch. The plant, here mentioned, is an inftance of this: the deleterious quality, from outward appearance, fmell, or tafte, of this vegetable, can hardly be fufpected unless by a botanist; and even be muft judge, on the bare conjectural foundation of fimilar virtues, in plants of the fame genus; which is perpetually found to fail, in numerous inftances..

I have heard this poisonous herb, called by the names of Wild-Carrot, Wild-Parfnep, Fever-Root, and Mock-EelRoot. The English names of plants are, in this country, frequently mifapplied, and do not distinguish them, with any certainty.

It does not resemble a carrot or parfnep, in the stalks, leaves, or flowers; though the root has fome resemblance to a parfnep, in colour and fmell; and the feeds have alfo a great likeness. It refembles the Angelica, and the mif

chief

chief that has been done by it, has proceeded from miftaking one for the other.

I will here infert the defcription, as it ftands in my catalogue, firft, in botanical terms, for fuch as are lovers of that science, and then in language, as plainly English as the fubject will admit, for the fake of thofe to whom those terms are less familiar.

Cicuta Venenofa. Claffis, Pentandria. Ordo, Digynia.

Radix perennis, fufiformis, perpendicularis; colore et odore pastinacæ radicis prædita. Caulis erectus, herbaceus, quatuor pedes altus, teres, fiftulofus, geniculatus, fubnudus, ftriato-canaliculatus, purpureus, fupernè tomentofus.-Folia petiolata, petiolis femi-amplexicaulibus, membranaceis, fulcatis, triternata, bipinnata, cum impari terminatrice, fæpe bilobo; foliolis feffilibus, oblongo-lanceolatis, ferratis. Folia ima longiffimè petiolata, triternata, foliolis ovalibus ferratis, ferraturis denticulatis.

Flores albi, in umbellis compofitis fubrotundis, fine involucro univerfali cum partiali polyphyllo. Locis campeftribus et collibus apricis gaudet: menfibus Julii Augustique floret.

Hemlock, Poifonous Mock-Eel-Root, &c.

The root is perennial; of the colour and fmell of a parfnep, but much smaller. The stalk rises four feet high, upright, round, lightly channelled, as if fluted; of a purple colour, hairy or downey on the upper part; hollow and jointed. There are only two, three, or four pair of leaves, placed oppofitely, at the joints, on membranaceous hollowed ftalks, which embrace the main ftem. The leaves are winged, terminated with an odd one, which is frequently divided into two lobes.

The folioles are oblong, and spear-shaped, fawed on their edges. The flowers are white, compofing a large compound umbel, without any involucrum; containing many smaller or partial umbels, each with an involucrumi of many small narrow leaves. The filaments and ftyles may be seen projecting beyond the flower leaves, being longer than the petals are. It grows on hilly barren lands, on dry grounds and open fields; though fometimes I have found it in moift places. It blooms in July and Auguft.

I have, lately, obferved several of thefe plants, with their lower leaves growing on very long stems, or petioles,, the petiole encreafing in length is divided into three; and, each of these subdivided again into three more. Each fmall ftem, of this last divifion, bears three leaves; which at their first putting out seem to be joined in one: but as they increase, with age, the lobes divide, and expand. themselves into three diftin&t leaves, which are oval fhaped, fawed on the edges; with denticles, or finall points, at: every ferrature. Those which do not fully expand, remain in two lobes, or three lobes, whence proceeds the greatvariety of the leaves, in this plant. The expanfion of the petiole varies very much, alfo in its divifions; from. whence it happens, that the leaves are often fimply pinnate, ternate, doubly ternate; triply ternate; which may vary the defcription, but the habit of the plant is fo ftriking, and fimilar, in every one, that no mistake can poffibly happen in diftinguishing it.

This plant is endued with a poifonous quality. Its operation, on the human body, has been pointed out by an accident, that happened, very lately, in my neighbourhood; the relation of which is as follows.

Sometime in the month of May last, three negro-boys were fearching, in the woods, for Wild Angelica, or, as they commonly call it, Eel-Root. They found a plant, and

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