dent from throwing fome twigs or leaves of the toxicodendron on the burning fire; for all the perfons that may be about the fire at the fame time will grow pale as if they were dead, and if the place be close, they may fall into almoft all forts of difeafes; yet thefe leaves, while they remain on the tree, though expofed to the fun, are quite harmlefs. Mercurialis relates, that in his time a military officer had occafioned the death of all prefent, by throwing a certain body on the fire, which body carried about one did no harm, but only became active by fire. Hence we learn, and this is fufficient for us, that, by the ftrong force of fire in the open air, particles may be extricated, which have a power fo to affect the nerves, as to produce all kinds of difeafes, and death itself. In other refpects we fee that the moft falubrious vapours proceed from other plants, as from guaiacum-wood, and that of the juniper tree. The dough of bread yields no fenfible fmell, but, baked in an oven, if a quantity of it is cut fresh in a clofe place, it may caufe death. Coffee-berries, whilft roafting in a place not blown through by the air, brought upon a man, who had too greedily fnuffed up their smell, a cardialgia and vomiting.

it is gradually brought to its most intenfe degree, water, fpirit, and oil, are fucceffively produced: if all thefe have paffed out, and the refiduum is still urged. by a vehement fire, it will eternally breathe forth fomething, never fhewing a deficiency. Hence it is called, by Van Helmont, the eternal coal, because that fimple oil, which adheres to the earth, is never feparated in a clofe veffel; if pounded fine, it is an infipid inert duft; if you expofe this coal to the open air, it will light by the application of fire; the furface only, contiguous to the air, becomes white; if the coal is broken, it gliftens every where within; if you go on burning it, it at length begins to be buried under afhes. It is impoffible to confume this coal otherwife than in the external furface, contiguous to the air, which being confumed, the fubfequent furface is alfo confumed, and, after fuch a confumption. of furfaces from fixty pounds of wood, one only of athes remains; nor can all thofe pounds, that are confumed, be gathered by any art; for the coal, in clofe veffels, cannot poffibly be confumed by any degree of fire.

But there are likewife fpirits from the fuffocation of fire. A live flame, urging a vegetable with the greatest force, and then fuffocated and extinguished, fo changes this body as to acquire a quality which may bring our body to death itfelf. If a piece of any kind of wood, or of the common turf, called alfo peat, is put into a chymical veffel, and the fire under

If one should write on paper, which is impregnated with a folution of orpiment, and dry this paper, no colour appears; but, if the paper is held over lighted coals, the letters will immediately be come black, and hence that which flies up is thus manifefted. If you place a burning coal between the fun and your eye, corpufcles will be feen carried upwards by a tre mulous motion; but it is doubted whether thefe are produced from the coal or fun. Van Helmont

called

called this way of changing this body a permutation into gas, and thinks that thefe corpufcles dwindle in this manner into the extremeft tenuity, and are transformed into a kind of water, which can rife to the extremity of the atmofphere. If fuch a coal be taken, and fire applied to it in a fpacious place that is fhut up, all the animals in that place will die; not from heat, for the contrary is evinced by experience; and from the burning of wood in a chamber that is blown through by the wind, difeafe or death never happens. Who would believe it, that the mere force of fire can fo change a very harmless body, if it acts upon it in the open air, when the most intenfe degree of fire can feparate nothing of the like, from the fame body, in a clofe veffel? It is therefore very improper to deride Van Helmont upon account of the word gas, for he explains it fuf. ficiently, and he thought a new and fingular name fhould be given to this change, the like of which we have no knowledge of.

Whilft Van Helmont, then an old man, was writing in a cold winter's day, he faw his ink freeze, and he ordered a chafing dish to be brought him, with coals that did not smoke. He felt no harm from it; but, his daughter coming in fhortly after, and faying that the perceived a ftrong ftench from the coals, the father, making a motion for quitting the place, falls back, hurts the hinder part of his head, and is carried away for dead. It may appear from this fingular example, that in a fpacious place, the doors open, the weather cold, without the leaft obfervation of contracting any illness, all the

actions of a man were in a moment abolished by nothing more than thefe fumes. Boerhaave relares of himself, that being in a parlour, drinking tea with fome ladies, where there was a chafingdifh of kindled charcoal for keeping the kettle boiling, and no chimney in the place, he faw all the ladies grow pale, and was fo affected himself by the fumes of the charcoal, that, had not the doors been opened, he felt himself tottering, and ready to tumble down. He likewife relates the fame effects on fome young ladies who lived in Leyden, and were fitting in a parlour, the windows of which gave into the street: the aunt of the mistress of the house, looking in at the window, announced her coming by tapping on the glafs with her fingers; the faw through the window all the ladies feated and looking at her, but not one of them making the leaft motion; fhe repeated her taps, and fo as to be louder, but none of them made her an answer; thinking they were paffing fome joke on her, the knocks in a paffion at the door, calling out, that the weather was too cold to be kept fo long in the ftreet: entering the parlour, the perceived the fumes of charcoal, and faw all the ladies pale and fenfelefs; immediately the ordered the windows to be opened, and all their faces to be fprinkled with water; by this means all of them foon recovered, but one of them vomited, another had a head-ach, yet none of them fuffered any thing more.

An English nobleman, travelling by boat in the night from Utrecht to Leyden, took with him into his cabin a ftoye, and ordered the

door

door to be kept fhut: when he came to his place of deftination, the waterman, opening the door, found him dead, with no other apparent fign than a little froth about his mouth. Four peafants, having made a fire in the hold of a fhip, were all found dead there. An intire family in the fuburbs, called de Hooge Morfch, were found dead from this caufe, by laying in the winter-time a pan of live coals in the midft of a room where there was no chimney, and the doors fhut.

Boerhaave fays, that he expe. rienced in himself, at the beginning of the ill effects from fuch vapours, an inclination to fleep, a tenfive pain in the head, a naufea, a vomiting of thick froth, and his head remaining as it were for many days full; but if the va. pour be denfe, nothing of thefe particulars is perceptible, but the affected die fenfelefs. This va pour, however, is not attended with any inconveniency, if a quantity of fea-falt is fprinkled on the fire, or if gunpowder is fet fire to in the clofe room. But when the ill effects have taken place, the beft remedy is to fprinkle cold water on the bodies, and to throw it upon the face and bare bofom. If cold water be thrown upon animals that have died in poisonous caverns, they are immediately brought to life; and hence, if men, who have died by the vapour of coals, were as foon as poffible treated in the fame man. ner, they might alfo perhaps be brought to life. In fuch cafe, however, this remedy is never to be neglected; for here there is no corruption, but a mere rest of all the moving parts, and in other

refpects nothing is changed; if therefore they are dipped into cold water, the elafticity of the veffels being increafed by the cold, the blood moves towards the inner parts through the veins; and the motion of the blood through the veins refufcitates its action to the heart, that is, refufcitates life itfelf.

The effects are not lefs noxious that proceed from places newly white-washed with lime, which diffufes, a fubaftringent and fetid vapour, efpecially upon the introduction of fire. For this reafon all newly built houses, if too foon inhabited, may bring on fatal diforders, or the worst of palfies, which can neither be cured by fo mentations nor baths. These ailments might like wife be occafioned by burning the parts of animals. If a place infected with the naftieft infects, as bugs or fleas, is fhut up clofe in all parts, and the bones of animals, or hartfhorn, are laid on the open fire, and the smoke is hindered to pafs out, all these ani. mals are killed; and greater ani mals may also be killed by the like fmoke. The wings of partridges, which about with a volatile falt, being burnt, have often excited hysterical paffions, and epileptic fits, where they were not, and diffipated them when they were prefent. A dog, killed in a heat of 146 degrees, of Fahrenheit's thermometer, emitted fuch a horrid and noisome stench, that those who came too near it in a moment fwooned away. In like manner, by the force of fire, dreadful fymptoms are excited from foffils. Aretæus obferves, in his chapter on epilepfies, that the ftrong fmell of the gagates ftone had immediately,

brought

brought on epileptic fits. Fire, acting on cobalt, which feems to be entirely inert, raises a thick white vapour that kills every animal, and this vapour, fixing upon the ceiling of a room, concretes anto a white flocculent matter, called arfenic, which is a moft potent poifon. If this cobalt, mixed with other foffils, and wrap ped up in a paper, be kept in a wooden box, it will eat through both the wood and the box; and if this happens in fo fmall a degree of heat, what muft it be, when this body is agitated by fire, How fixed is nitre, whatever way tried! If it melts in the fire, it remains fixed and mild; if bolar or uncalcinable earths are mixed with it, and both expofed to the fire, it will yield a fpirit, volatile like alcohol, which corrodes and diffolves all things, except gold and glafs; and it is very hurtful to the lungs. The fame way a fpirit afcends from fea-falt, which corrodes all things. If fulphur be fublimed ten times, it remains mild, as before; but, if fet on fire, it kills animals, and corrodes and conftringes all things.

On the effect of the imagination on a different body. From the fame.

WHAT muft we think of

that action excited in the

common fenfory by the help of that faculty we call the imagination, which fo difpofes the com. mon fenfory from internal caufes, as it was before difpofed from ex. ternal? For my part, I fay, that the force of the common fenfory is exerted by a true corporeal effect out of the human body, as ap

pears from women that give fuck, or the pregnant, who, by this pro. perty of the common fenfory, change the foetus in their womb. I have feen my felf an inftance of a healthy woman fuckling a very healthy child, who was fo disturbed by another woman scolding at her, and fo irritated as to be all over in a tremor; yet, by fuckling her child in this condition, it was im mediately convulfed, and remained epileptic. Who now will fay what could be in her milk, and how it could receive the power of producing thofe corporeal changes? But it fhould be a point of pru. dence with a nurfe never to fuckle a child when the is under any dif turbance of mind. We can in fome measure account, why a drunken nurfe inebriates a child; but we cannot fo eafily understand, how milk can be fo far changed, merely by the paffions of the mind.

The fame may hold true in pregnant women. There perhaps arifes in the pregnant mother a certain idea: if it be frequent and cuftomary, it does not affect her; if unusual it fometimes affects her, and fometimes not. This idea proceeds fometimes from feeing or hearing, or from the imagination alone, or the appetite alone. The fudden fight of a

thing not feen before impreffes

on an infant the figure of that thing. From hearing the hiftory of fome dreadful misfortune or calamity, the frighted mother imbibes a fimilar efficacious idea; and the fame happens as often from the imagination, dreams, and that depraved ftate of the appetite called longing.

A very handfome lady, yet one

of

of frict morals, and abftaining from all manner of excefs in the ufe of wine, being with child, conceived a longing for drinking Rhenifh wine. She long ftruggles againft this paffion, her husband examines her about it, and fhe at laft confeffes what it is: he takes her to a wine-cellar in Amfterdam where the drinks fo great a quantity, as would fuddle two ftout men yet no harm enfued to her form her copious draught; and, when fhe had once fatisfied her longing, fhe remained afterwards free from it. Another women had an exceffive longing for eating a morfel out of a butcher's fhoulder, and could enjoy no reft, till fhe had found means once to bite him.

A princefs was delivered of a black daughter, by only feeing for the first time a blackmoor. As this woman had never been left alone, but was conftantly attended with the greatest care, all fufpicion was void of any commerce with a black. This idea, once given birth to, does not rest; it occupies the whole fenfory, and every moment quickens the woman's fancy.

But fo unufual a thing muft ftrongly affect the very moment; for, if it affects but little, it will have but little efficacy: but, if it be fo forcibly impreffed on the mind, as that the woman fhould fay her whole infide is moved, then a future veftige of the evil is boded; or if, in the very time of fuch an idea arifing, a horror and tremor are felt fhaking the whole body, it is an infallibie fign that a veftige is left; which does not happen, if there be no horror.

All phyficians obferve, that there is always a horror, when any com

motion is made in the body that changes its actions; then a cold tremor trickles through the bones; as Virgil fays. He that is ill of an ague enjoys fome days of health; but he perceives a cold fhivering, and the fever foon comes upon him. I have heard from the experienced, whilft the plague was rife, that, as foon as they felt a fenfation, as it were from cold water being poured upon them, they were immediately taken ill of the plague. We fhudder in the like manner, when the variolous poifon infects us; when the ftitch of the pleurify invades us; and that fhuddering penetrates through the whole body: men feel then fomething cold, which fufpends, as it were, for a time the vital motions; and it is propagated with tremor, and almoft changes the whole body. I would be glad to have a preceptor, who could explain to me, how and whence this horror arifes.

I alfo obferve pregnant women to have had, in almoft all these cafes, a fpontaneous motion, and to have applied their hand to a certain part of the body, and that the foetus then retained the mark impreffed in the fame part; if they had not moved their hand to it, fcarce any thing heterogeneous would have happened. Hence women with child should be cautious of moving their hand to a part that is not covered by their cloaths, left the deformity might afterwards be confpicuous. But there is a fimilar faculty in every man, which we cannot underftand: Suppofe a perfon's eyes inflamed, and, as it were, fparkling with fire; if you look at him, you will alfo rub your eyes. He

that