PROPOSITION I.

TO deliver my Thoughts about this matter somewhat more di­stinctly, I shall lay them down in the four ensuing Observations or Pro­positions, whereof the first shall be this: It seems probable that in divers places, the Salubrity or Insalubrity of the Air considered in the general, may [Page 5] be in good part due to subterraneal Expirations, especially to those that I lately call'd Ordinary Emissions. For in some places the Air is observ'd to be much more healthy, than the manifest qualities of it would make one expect: and in divers of these Cases I see no Cause to which such a happy Constitution, may more pro­bably be ascrib'd, than to friendly Effluvia sent up from the Soil into the Air; which Particles either by promoting transpiration (that great instrument of health and recove­ry;) or by hindering the producti­on, or checking the Activity, of Morbifick ferments; or by mortify­ing and disabling some noxious Par­ticles, that would otherwise infest the Air, or by other ways, that I shall not now stay to enumerate; may not a little contribute to keep the Bodies of those that live in that Air, in that regular and desirable state, we call Health. I know in­deed that 'tis generally thought, and often true, that Mineral Bodies do [Page 6] send up Exhalations, hurtfull not on­ly to Plants, but to Men; but when we mean Subterraneal things inde­finitely, though (Men are wont to look upon them but slightly under a general confused Notion) we em­ploy a word more comprehensive than most men are aware of, there being a great variety, as well as mul­titude of Bodies, that Nature has lodg'd in her dark Store-houses un­der the surface of the Earth. And of these differing sorts of Bodies, though 'tis probable that the grea­test part are such whose Effluvia are unhealthfull to Men, yet there may be others whose Emanations may be friendly to him; I have known it observ'd that over some Tin Mines in the Western parts of England, not only Trees, but far more tender Plants, as Grass, are wont to prosper and flourish, and (if I much misre­member not) I have seen verdent Trees growing just over a vein of a­nother sort of Mineral, that lay near the surface of the Earth: And 'tis [Page 7] likewise observable about those that constantly dig in those Tin-Mines, that they do not lead a short and sickly life as in many others, but ar­rive at a great and vigorous Age. And an Ancient Possessor of some of these Mines being askt by me, whe­ther amongst the otherwise differing Exhalations that ascended into the Air, he did not find a difference as to smell bad or good; he answer'd, that though most of those visible fumes had a smell that participated enough of Sulphur or Bitumen to be offensive, yet some others were so far from being ungratefull, that they were well scented. And on this occasion I remember, that not long since, a Friend of mine, and another Virtuoso, being Partners in a chargeable Attempt to discover a Mine, in digging deep for it, they accidentally broke into a vast Sub­terraneal Cavern, into which, be­cause the Diggers would not ven­ture to descend, one of these curi­ous Gentlemen caused himself to be [Page 8] let down, and there found the Air very temperate and refreshing, and that he long breath'd it with delight, and on the floor, or Soil (which reach'd farther than he could disco­ver) he found many and various Minerals most of them embryona­ted, or imperfectly form'd, and store of a kind of Mineral Earth, whose smell was fragrant and very pleasant both in his Judgment, and that of some Ladies. And though, when some of those Minerals were brought to me, a small lump of this Earth that was among them, had been kept so long in the Air, as to spend most of its Odoriferous Particles, yet the smell it still retain'd, was, though but faint, yet pleasing.

That from Fossiles that lye hid under the surface of the Earth, and have a considerably large Spread, there may ascend store of wholsome Effluvia into the Air, seem'd to me the more probable by what I noted at my last being in Ireland, where, being invited by a Brother of mine [Page 9] to pass some time in a Countrey house of his, to which there be­long'd a very large Sheep-walk that produc'd short, but excellent Grass; I learn'd (and was easily perswaded by some things I took notice of) that this place was justly reputed very healthfull, and this Salubrity of the Air, together with the sweet­ness of the Grass, some circumstances invited me to ascribe to this; That the Soil was sustain'd by a large tract of Limestone, which I sup­pos'd to emit continual exhalations into the Air; which conjecture will perhaps with the less scruple be assen­ted to, if I add that it has been long and generally observ'd, that as far as the Limestone extends, that tract of ground makes the Snow that falls on it thaw, or melt much sooner, than it does on the Neighbouring Lands.

After I had made this Observation, I mention'd it in discourse to an in­quisitive Person, that had seen and been employed about several Mines; and I asked him whether he had met [Page 10] with any thing of this kind; to which he answer'd me, that in Der­byshire, at a place which he nam'd to me, he and others had observ'd, that a large tract of Limestone land was so warm (as they speak) as to dissolve the Snow that fell on it, ve­ry much sooner than another great scope of Land, which was divided from it but by a glin, where the Soil did not cover Limestone, but Free­stone.

Afterwards, discoursing of this Subject with an ingenious Person, that had visited the Hungarian, and Bohemian Mines; he told me, that during his stay among the former, he often walked abroad with the Overseer of them, a famous and ex­perienc'd Mineralist, who delighted to breathe the fresh morning Air upon some Hills abounding with Mine­rals; that his Guide made him ob­serve, that when they were over a tract of Land that afforded much of that noble Oar (which by a German Name he called Rot-gulden ertz) he [Page 11] found the smell to be pleasing, and the Air refreshing. And whereas, in passing over some other Mines, he found himself molested by offensive fumes; he felt no such effect, when he was upon that scope of ground under which there lay veins of Cin­nabar, or, if you please, a Mine of Quick-silver Our: And his ancient Guide told him, that next the Rot­gulden ertz before mentioned, the Soil containing these Cinnabarine veins, was that whose incumbent Air was the most eligible for plea­santness and Salubrity. And I the less wonder, that in some places the subjacent Fossiles should impregnate the Air with wholsome Effluvia, be­cause I remember I had the Curiosi­ty to ride many Miles, (though in the depth of Winter,) to see a scope of ground that was famous for a good Pottery; where, besides many other Mineral Earths that I took notice of, there was a Pit or Groove, that reach'd, if I mistake not, fifteen or twenty foot beneath the surface of the [Page 12] ground; whence they dug up a kind of white Clay, so richly im­pregnated with subtile and noble parts, that it afforded a Chymist or two of my Acquaintance (for I had my self no opportunity to distill it) good store of a Subtile Spirit, of a Volatile and Saline Nature, which upon trial they highly extoll'd for it's Cordial, and other Virtues in Physick; and which, by some pecu­liar Mechanical trials I made with it, I concluded to abound with a Vola­tile Salt, not unlike that of Urine or Hartshorn. And since by this in­stance we see, that some unsuspect­ed Fossiles may be enrich'd with Medicinal and Fugitive Salts and Spirits; it may reasonably be sup­pos'd, that these ascending into the incumbent Air, may highly conduce to the Salubrity of it. And the Cu­riosity I have had to examine Chy­mically some Boles, and other Bo­dies, which are wont to be unregar­dedly compriz'd under the confus'd notion of Earths, makes me suspect, [Page 13] that there may be far more Species of Salubrious Fossiles than many have yet taken notice of.

But peradventure you will much the more easily admit in general, that Subterraneal Tracts of great extent may for a very long time send up in­to the Air copious Expirations, not discernable by any of oursenses, nor commonly suspected to be found in that Body, if you please to consider with me (what I do not remember to have been taken notice of to this purpose) that the common Air we live in, and breathe, does always a­bound, and for many Ages has been impregnated, with the Copious Mag­netical Effluvia of the Earth; which our industrious Gilbert, and after him some learned Jesuits and others, have proved to be a great, though faint Magnet; and whose emanati­ons, as they constantly stream through the Air, I have elsewhere by parti­cular Experiments shewn to be capa­ble of passing through the Pores of Glass it self, and acting almost instan­taneously, [Page 14] and yet manifestly, upon Bodies hermetically seal'd up in it. But, though from what has been said it may be inferr'd, that 'tis not im­probable the Salubrity of the Air in some places may be chiefly, or at least in part, due to the wholsome Expirations of Subterraneal Bodies; yet, generally speaking, the Air is de­prav'd, in far more places than it is improv'd, by being impregnated with Mineral Expirations. And in­deed, besides that, among the Mine­rals known unto us, there are many more that are noxious, than that are wholsome; the power of the former to doe mischief is wont to be far more efficacious, than that of the latter to doe good; as we may guess by the small benefit men receive in point of health by the Effluvia of any Mineral, or other Fossile, known unto us, in comparison of the great and sudden mischief that is often done by the Expirations of Orpi­ment, Sandarach, and white Arse­nick; for, though that sold in Shops [Page 15] is factitious, being made of Orpi­ment sublim'd with Salt, yet it is found Natural in some Hungarian, and other Mines. On which occa­sion, I remember that the ingenious Person lately mention'd to have with his Guide taken the Air upon the Hills of that Mineral Countrey, an­swer'd me, that, when his Guide and he walk'd over some veins of these noxious Minerals, he met with seve­ral Odorous Steams, which, though differing from one another, agreed in this, that they were all offensive to him; and particularly, some of them by their unwelcome sharpness, and others by giving him a trouble­some difficulty of respiration. I will not here urge those sulphureous steams, that so suddenly deprive Dogs of sense and motion, in the Neapolitan Grotta de Cani; because there the Exhalations are too much included, and as it were pent up: But it is very proper to allege for my present purpose the Aorni or Averni, which are men­tion'd [Page 16] by good Authours to be found, some in Hungary, and some in other Countries; for in these places there ascend out of the Earth such noxi­ous and plentifull exhalations, as kill those Animals that draw in the Air they infect; and some of them are a­ble to precipitate, even the Birds that fly over the Caverns that emit them. But there are a multitude of Places, where 'tis not so manifest that hurtfull exhalations ascend into the Air, and yet they really do so: There being in many places whole tracts of Land, that near the surface of the Earth a­bound with Marchasitical Minerals, as these do with a sharp vitriolate Salt, which, together with the ill condition'd Sulphur that they also plentifully contain, ascend into the Air, and render it corrosive. On which occasion I remember, that for Curiosities sake I took some En­glish shining Marchasite; and caus'd a pound of it to be distill'd in an Earthen Vessel with a good fire, by which means, notwithstanding it's [Page 17] dryness, I obtain'd two or three spoonfuls of a Limpid Liquor, that smell'd very strongly, like that which the Helmontians call Gas Sulphuris; and which appear'd manifestly to be of an acid Nature, both by the taste, and by it's readily corroding, and dissolving unbeaten Coral, even in the cold, to mention here no other Tryals that I made with it. And the Mineral afforded me, together with this Liquor, about an ounce and three quarters of inflammable Sulphur, part whereof ascending (as may be guess'd) in the form of very agile Corpuscles, these fasten themselves all about to the inside of the Receiver, and there compos'd divers thin Coats, or Films, as 'twere, of Sulphureous matter sticking to one another; which at their first taking off, and for some time af­ter, might be bent or folded like leaves of paper, but afterwards har­den in the Air. Mineralists, and some other good Authours, mention divers Places as abounding with Mar­chasitical [Page 18] Fossiles, but I am apt to think, they are far more common than is vulgarly taken notice of; for I have met with them where one would little expect them. And, though in England all our Vitriol (which is now plentifully vended into Foreign parts) be made of Vitriolate Stones, or Bodies that pass for stones; yet that is not true which our Mineralists are wont thence to conclude, that there is no other Vitriolate or Marchasitical matter in England: for a famous dea­ler in Fossiles, having found a Mine, which he knew not what to make of, and therefore carefully conceal'd, address'd himself to me, because, he said, he knew I would not betray or supplant him: and having at his desire taken a private view of what he had discover'd, I presently found it to be a vein, that lay at some depth under ground, and ran along (how far I know not) like a vein of Me­talline Oar, (and for such upon that account he mistook it) consisting of [Page 19] a black and heavy stuff, which up­on a few easie trials I quickly found to be of a Vitriolate Nature; inso­much that, somewhat to my won­der, I was able to make it yield in few hours store of pure Vitriol, without any troublesome or artifici­al preparation.

PROPOSITION II.

UNder the name of Endemical Diseases, I do not comprise those onely that are very peculiar to this or that Countrey; as the Plica is said to be to Poland, (whence it re­ceives its name of Polonica;) or an odd kind of Colique in one part of France, (from which 'tis called la Colique de Poictou;) but also those that are more rise in some Coun­tries [Page 20] than in most others; such as Agues in Kent, and in that part of Essex they call the Hundreds; the Consumption (though that be an ambiguous name) in England, whence Foreign Physicians call it the Tabes Anglica; and Fluxes of the Belly in Ireland, where they are so rise as commonly to pass under the name of the Countrey Disease.

That these Endemical, or (if we may so call them) Topical Distem­pers, do in many places proceed from some excessive Heat, Moisture, or other manifest quality of the Air; from bad Diet, vulgar Intemperance, and other Causes that have little or no connexion with Subterraneal Reeks, I readily grant. But, that in some places the Endemical Disease may either be principally caus'd, or much fomented, by noxious Effluvia, I am enclin'd to suspect upon the following grounds.

• 1. There are some places, in which the Endemical Disease cannot be probably imputed to any manifest [Page 21] Cause; as he may perceive that shall consider how often it happens, that the Causes which are assign'd of such Diseases, if they were the true ones, must produce the like Distempers in many other places, where yet it is notorious that they are not Endemi­cal.
• 2. That Subterraneal Bodies may send up copious Steams, of different kinds, into the Air, has been alrea­dy made out.
• 3. It has been also shewn, that the Matters that send up these Efflu­via, may be of a large extent. And I remember on this occasion that I have sometimes observ'd, and that in more Countries than one, a whole tract of Land that abounded with Minerals of one kind; and within no great distance, as perhaps a Mile or a League, another large tract of Land, whose Subterraneal part a­bounded with Minerals of a very differing sort.
• 4. We have also above declar'd, and 'tis highly probable from the [Page 22] nature of the thing it self, that those copious steams (Saline, Sulphureous, Arsenical, Antimonial, &c.) that im­pregnate the Air, may very much conduce to make it hurtfull to a hu­mane body, in the way requisite to produce this or that determinate Disease: as I not long since related from the Chymist that visited the Hungarian Mines, that in some pla­ces he found the Reeks ascending from them into the Air (though in an elevated place, and expos'd to the Winds) make him as it were Asthmatical, and give him a trou­blesome difficulty of Respiration. And here let me add an Observati­on, which perhaps will not be thought fit to be slighted by Physi­cians: namely, that some parts of the substance of the Air (for I speak not of its Heat, Coldness, or other such Qualities) do not onely affect humane bodies, or at least many In­dividuals among them, as they are taken in by Respiration, but as they outwardly touch the Skin: and the [Page 23] Skin being (as I have elsewhere shewn) full of Pores, and those perhaps of different sizes and figures, those Corpuscles that get in at them may have their operation, even up­on the most inward parts of the body. To make this more clear and probable, because 'tis a thing of importance, I desire these things may be observ'd.

1. That when I speak of the Air, I do not in this place understand that Air, which I elsewhere teach to be more strictly and properly so call'd, and to consist of springy Par­ticles; but the Air in its more vulgar and laxe signification, as it signifies the Atmosphere, which abounds with vapours, and exhalations, and in a word with Corpuscles of all sorts, except the larger sort of springy ones; and many of them may be so small, and so solid, or so conveni­ently shap'd, as to get entrance at some of the numerous Orifices of the minute or miliary Glandules of the Skin, or at other Pores of it. [Page 24] Thus, though paper be not pervi­ous to the uncompress'd elastical parts of the Air, yet it may be easi­ly penetrated by other Corpuscles of the Atmosphere: for I remember, I have for Curiosities sake prepar'd a dry body, out of a substance belong­ing to the Animal Kingdom, which being lapt up in paper, would, without wetting or discolouring, or any way sensibly altering it, pass in a trice through the Pores of it in such plen­ty, as to have not onely a visible, but a manifest operation on bodies plac'd at some distance from it. And though a bladder almost full of Air, having its neck well tyed, be held near the fire in various postures, the elastical Air, though rarefied, or attenuated by the heat, will rather burst the bladder, (as I have more than once found) than get out at the Pores, yet we have often made a certain substance, belonging to the Mineral Kingdom, that, if a bladder were wet or moist, (as the Skins of living Men are wont to be) would readi­ly [Page 25] pervade it, and have a sensible operation, even upon solid bodies plac'd within it. This Experiment (that I can repeat when I will) is therefore the more considerable to our present purpose, because in the bladder of a dead Animal, the Po­rosity may be well suppos'd to be much less than it was in the Animal when alive; in which state the parts of the humane body are much more perspirable than one would easily believe, partly because of the heat that is continually diffus'd from the heart, and partly because of the co­pious steams that are in perpetual motion, and keep the parts warm, moist and supple: And it is not to be pretermitted in our present in­stance, that the bladder of Urine consists not of a single Membrane, and is probably of a stronger tex­ture, by reason of the subtile salt liquor it is instituted to contain, than many another Membranes of the body, or the Epidermis. And this is the first thing I would have noted.

[Page 26]The next is, that, whereas in the Instances newly recited, and some others that are by and by to be men­tion'd, the effects were produc'd when the ambient Air, impregnated with Mineral Corpuscles, had but a very short time (perhaps not ma­ny minutes) to work upon the bo­dies expos'd to it: In those Coun­tries that are very subject to Endemi­cal Diseases, the Inhabitants are wont to live all the year long, and per­haps during their whole life, expos'd to the action of the vitiated Air: and how much a far shorter time will serve, to make the Corpuscles that rove in the Air, penetrate into bodies of no very close contexture, may be guess'd by the breaking even of the bigger strings of Lutes and Vi­als, by the numerous (though invi­sible) vapours, that get into them in rainy weather; and much more by the effects of such vapours, when insinuating themselves in swarms into the Pores of a Rope, they shorten it so forcibly, as to enable it, by shrin­king [Page 27] it self to lift up and keep sus­pended considerable weights, as I have elsewhere shewn by tryals pur­posely made. These things may ren­der it probable, that, though in a small compass of time the noxious Effluvia that rove in the Air, may be too thinly dispers'd in it, to in­sinuate themselves in any considera­ble number at the Pores of the Skin; yet, by reason of the continual con­tact of the Air, (especially as to the Face, Hands, and some other parts) which may last day and night for many months, or perhaps years, there may be opportunity for a considerable number of morbifick Particles, to insinuate themselves into the cutaneous Pores.

3. And thus having once got en­trance, they may by the capillary Vessels that reach to, or terminate at the Skin, pass on to somewhat lar­ger Vessels; and so may get into the mass of bloud, and by its Cir­culation be carried to all the parts of the body; and so be enabl'd both to [Page 28] deprave the bloud, and other juices themselves, and to gain access to any determinate part of the body, which their peculiar shapes, figures, &c. qualifies them to produce some par­ticular Distemper in. This whole Doctrine may be made more proba­ble, by what experience shews of the virtues of certain Plasters, es­pecially Mercurial ones, in Distem­pers that are not at all, or at least are not chiefly Cutaneous; and (which comes more home to our Argument) of the efficacy of Periaptae, and Ap­pensa, such as Piony-root, Bloud-stone, Lapis Nephriticus, Quick-silver in a Quill, a dry'd Toad in a Cesnet Bag, &c, whereof, though many answer not the Characters that are wont to be given of them, yet some of them, experience has convinc'd me to be of greater efficacy than I expected: And much more activity may be presum'd to be, in divers noxious Effluvia from Subterraneal Bodies; as may be gather'd from the effects of the Mercurial Girdles, that some un­wary [Page 29] persons wear to cure the Itch; and from what I elsewhere relate of the fits of the Colicque, often pro­duc'd in a Friend of mine by the Effluvia of masses of Loadstone. And this last example may serve for a proof of another part of our Hy­pothesis, by shewing that Mineral Effluvia, may not onely be noxious in a general way, but may produce this or that determinate Disease. That Arsenical Appensa, though much ex­toll'd by divers Physicians themselves, and sold dear by Empyricks, as (if worn near the Heart) wonderfull Amulets against the Plague, have (es­pecially in some persons and circum­stances) produc'd some of the noxi­ous effects of Arsenical Poysons, and particularly caus'd in some great faintness and dispiritedness, I find by the Testimony of divers eminent Physicians. To which I shall add a remarkable one, which may pro­bably be referr'd partly to this third Observation, as well as to what I lately deliver'd about the bad effects [Page 30] of Mineral Exhalations, breath'd in with the Air they vitiated: and I the rather mention this Case, because 'tis not onely an odd one, but is a considerable Argument to shew, that noxious Mineral Expirations may manifestly produce a determinate Distemper in unlikely parts of the body. The Observation is this; I knew, and on some occasions em­ploy'd, a Chymical Laborant that fan­si'd that he could make a rare Medi­cine out of red Arsenick, (as some call what others style Sandarach,) which is thought to differ little from common Orpiment, saving its being much higher colour'd: this Laborant then working long and assiduously upon this Mineral, and rubbing it frequently in a Mortar, came divers times to me; and complain'd of a disaffection he thence contracted in the Organs of Respiration; for which I gave him something that happen'd to relieve him; which en­courag'd him to complain to me of another Distemper, that, though [Page 31] not so dangerous, did often very much molest him: which was, that when he was very assiduous in the preparation of his Sandarach, it would give him great Pains, and (if I misremember not) some Tu­mours too, in his Testicles: And this, for ought I know, happen'd to him as long as he was earnest about that Process; for the Medicines that had reliev'd him in his other Distemper, did not remove this: and I having occasion to go for a while into the Countrey, found him gone at my return. It may strengthen the Con­jecture lately propos'd, of the possi­ble insinuation of Effluvia that rove in the Air, at the Pores of the Skin, if I add that I have had the Curiosi­ty to enquire of more than one Tra­veller, that had visited the famous Pico of Tenarif (at whose upper part there are found scatter'd parcels of Sulphur, and divers manifest to­kens of a Vulcan) whether the Sul­phureous Steams (that I suppos'd to be copious near the top of the [Page 32] Mountain) did not work upon the silver Money they had in their Pock­ets, and discolour it: to which he answer'd that 'twas no uncommon Observation, to find at mens return from visiting the top of the Hill, that the Money they carried about them was blackn'd, and that he him­self had particularly observ'd it to be so: which might easily gain cre­dit with me, who have divers times made a preparation of Sulphur, which, even in the cold, sends out exhalations so penetrant, that, ha­ving for tryals sake put some pieces of Coyn (which ought not to be Golden) into a Leather Purse; they were able, and that in not very ma­ny minutes, to discolour manifestly the Money, in spite of the interpo­sition of the Purse that contain'd it. But I had a more considerable instance of the efficacy of the Sulphureous Expirations of the Pico of Tenarif, by a sober Person that is one of the chief Directours of the famous East-India-Company of London; who, [Page 33] being question'd by me about some circumstances of his Journey to vi­sit the top of that stupendious Moun­tain, answer'd me, that among other effects the Sulphureous Air had upon him, (who is of a very fine com­plexion) he found at his return to the bottom, that his light-colour'd Hair had manifestly changed colour, and was in many places grown for­ked at the ends. These Observati­ons may make it probable, that Mi­neral Exhalations may not only af­fect humane Bodies, as they are drawn into the Lungs with the Air they swim in, but as they insinuate them­selves into the Pores of the Skin.

One considerable Objection I foresee may be made, against the Proposition I have been all this while endeavouring to render pro­bable; namely, that 'tis scarce con­ceivable, that in so many Ages as Endemical Diseases have afflicted some Countries, the Subterraneal Matter, to which I do in great part im­pute some of them, should not be [Page 34] wasted and spent. I might perhaps on this occasion move a doubt, whe­ther we have had such continued ac­counts of the temperature of the Air, of all the Countries where Diseases are now Endemical, as to know that they have been always so; and that some of those Diseases have not been worn out here or there, and some others have not of later Ages begun to appear in this or that place. But contenting my self at present to have hinted this Question, I shall not stay to discuss it; but proceed to offer three things, by way of direct answer to the Objection.

1. And first, I think it very pos­sible, that divers Subterraneal Bodies that emit Effluvia, may have in them a kind of propagative or self mul­tiplying power: I will not here ex­amine, whether this proceed from some seminal Principle, which ma­ny Chymists and others ascribe to Metals, and even to stones, or (which is perhaps more likely) to something analagous to a Firment, such as in [Page 35] Vegetables enables a little sour dough to extend it self through the whole Mass; or such, as when an Apple or Pear is bruis'd in one part, makes the putrify'd part by degrees to trans­mute the sound into it's own like­ness; or else some maturative pow­er, whereby an inanimate Body may gradually admit of such a change, or acquire such Qualities, as may be in Mens estimate perfective of it, and perhaps give it a new denomination; as Anana's in the Indies, and Medlars, and some other fruits here in Europe, do after they are gathered, acquire (as it were, spontaneously) in pro­cess of time, a consistence and sweet­ness, and sometimes Colour and O­dour, and in short such a state as by one word we call maturity or ripe­ness: and so some Metalline Ores, and some Mineral Earths themselves, have been observ'd by Mineralogists, to acquire in tract of time such a change, as to afford some Metal or other Bo­dy, which either it did not afford before, or at least did not afford [Page 36] so copiously, or so well qualify'd. This I have purposely made out in ano­ther Paper: and the Observation particularly holds as to Niter, which is thought to be the most Catholick Fossile we have; and to be at least one of those Fossiles, that do the most plentifully emit Effluvia into the Air.

2. When I consider, that even in those Mines that are accounted deep ones, the Spades of Men are not wont to reach to the ten thousandth part of the thickness of the Earth, between its Surface, and its Centre, which yet is but its Semi-diametre; I can­not but confess, that we know very little of the Nature or Constitution of the lower part of the Terrestrial Globe; since we know little or no­thing experimentally, of what lyes beneath that Comparatively very thin Crust or Scurf, (if I may so call it) that Humane Industry has been hitherto confin'd to. And upon this account I do not think it absurd to suspect, that from the lower Subter­raneal [Page 37] Regions there may be, either continually, or periodically, emitted into the Region of Mines (if I may so call it) great store, and variety of Mineral Exhalations, which may continually repair the loss of those, that from time to time ascend out of the Fossile Region (as I may also call that of Mines) into the At­mosphere. But the things I could alledge to Countenance this Conject­ure, must not be insisted on in this place. Therefore I proceed to con­sider.

3. That Bodies so heavy, and consequently so abundant in parts of solid matter crouded together, as Mi­nerals, and other Fossiles are wont to be, may well be suppos'd capa­ble, without destructively wasting themselves to emit store of such mi­nute Particles as Effluvia, for an exceeding long time. This will be easily granted by him that shall con­sider the particulars laid together in a small Tract, that I purposely writ, about the admirable Subtilty [Page 38] of Effluvia. And 'twill be the more easily believ'd, if it be con­sider'd how long some Load-stones, sever'd from their Mine, have been kept in the Air without any nota­ble, or perhaps so much as sensible diminution of their Virtue. And this brings into my mind what an eminent Physician, who was skill'd in Perfumes, affirm'd to me about the durableness of an Effluviating power, that was not natural to a Metal, but adventitious, and intro­duc'd by Art: for he assur'd me that he had a Silver Watch-case, that had been so well perfum'd, that though he usually wore the Watch in his Pocket, it continued to be well scen­ted sixteen years. The same Person had a way of perfuming factitious Marble quite thorough, whose grate­ful Scent he affirm'd would last ex­ceedingly; and of this perfum'd Marble he presented me a Ball, which having been some months af­ter gotten from me by a great Lady, I was disabled from observing the durableness of the fragrancy.

[Page 39]I might perhaps be thought wan­ting to my Cause, if, before I dismiss the Proposition I have been all this while discoursing of, I should not observe, that Subterraneal Effluvia may contribute to Endemical Disea­ses, not only as they vitiate the Air, that Men breathe in, or are imme­diately touch'd by; but as they may impregnate or deprave the Aliments that men feed upon. For first, they do mingle themselves with the water, which either men drink it self alone, (as is the Custome with many Nati­ons, and of some men in most Nations; or make of it their Bear, Ale, or other factitious drinks, prepar'd of Water and Barley, Oats, Rice, &c. That divers Springs, and other Wa­ters are imbued with Mineral Cor­puscles, may be judg'd by some of the Medicinal Springs: for, though divers Acidulae and Thermae afford good store of palpable Sulphur or Salt, yet all do not; and having purposely examin'd a famous one, I could with a pair of nice Scales [Page 40] scarce discover any sensible diffe­rence at all between the Medicinal Water, and the common Water that was to be met with thereabouts. And that which impregnated this, and which I found by tryal on my self, and some other Bodies, enabl'd it to work very manifestly like a Mineral Water, was a sort of Corpuscles so minute and subtile, that if the Bot­tles were not kept well stopt, they would in a short time vanish, and leave the Liquor dispirited. Expe­rience has assur'd me, that there are ways of making common water violently and hurtfully operative upon Humane Bodies, though its sensible qualities would not make one suspect any change in it: but the ill use that bad men may make of such Liquors, makes me forbear to express my self more clearly: nor is it necessary that I should add anything to confirm the propos'd con­jecture, save what may be inferr'd from these two Particulars; the first whereof is the scarce at all sensible [Page 41] change that may be made in wa­ter, and some other Liquors, that are made strongly Emetick by Cro­cus Metallorum, and by Antimo­ny vitrify'd without addition: and the second may be taken from those Averni, whence there con­tinually ascend such pernicious Ex­halations, as in some places intoxi­cate or kill even the Birds that fly over those poysonous vents; for if such Exhalations, or even far less deadly ones, should (as they may be reasonably suppos'd, sometimes to do) meet with either running or stagnant Waters in their ascent, there is little doubt to be made, but they will impregnate them, and make them noxious. And on this occa­sion we may pertinently recall to mind, what I have formerly deli­ver'd about a place upon the Bor­ders of Lancashire, where the Wa­ter and Mud of a Ditch is so copi­ously impregnated with Subterra­neal Exhalations, (whether they be bituminous, sulphureous, or of some [Page 42] unknown kind) that they may easi­ly be fir'd at the surface of the Wa­ter, or Earth, and made to burn like a Candle, as an ingenious man did at my Request successfully try.

But there is another account, up­on which the Effluvia of the lower parts of the Earth may have a grea­ter stroke in producing of Endemical Diseases; namely, as they mingle with the Water, and other Liquors that are necessary to the nutrition and growth of Plants; and, by depraving those juices, make the vegetables that are nourish'd by them unhealthy for the men that eat them, or make drinks of them: and these noxious Exhala­tions may be suppos'd in many places to impregnate the juices of the Earth, much more copiously than they do the running or stagnant Waters lately spoken of: because the difficulty of pervading the Earth in their ascent, may so long check them, as to make them very numerous in a small space, and perhaps make them convene into Bodies, so far of a Saline Nature as to [Page 43] be dissoluble either in common Water, or some other Subterraneal Liquor; by whose help, as by vehicles, they may insinuate themselves into the roots of Plants, and be thence con­veyed to other parts. Divers things might be alledg'd to keep this con­jecture from being improbable, if I had leisure to insist on them: but I I shall now only mention two things that on this occasion come into my mind: the first whereof is, that en­quiring of a famous Chymist, who liv'd in a Countrey abounding with Mines of Vitriol, whether he did not observe, that the Oaks growing over them were more solid, or heavy, than those Trees are elsewhere wont to be; he answer'd me, that he did, and that the difference was remarkable: The other is, that the parts of some Minerals, (probably by reason of the smallness and solidity of the Corpus­cles they consist of) are capable of in­sinuating themselves very plentifully into the pores of growing Vegetables, without being really subdu'd by what [Page 44] Philosophers are pleas'd to call the Concocting Faculty of the Plant; and, instead of being assimilated by the Vegetable, they retain their own Mi­neral Nature, and upon the recess or evaporation of the juice that serv'd them for a vehicle, may sometimes dis­cover their being Mineral, even to an unassisted Eye. For I remember I have seen a piece of a Vine, that grew not far from Paris, which being broken, I perceiv'd a multitude of the internal Pores of the root, and, if I mistake not, part of the Trunk also, to be stuff't with Corpuscles of a Marchasitical Nature; as manifestly appear'd by their Colour, and their shining lustre, and also by their weight.

There goes a Tradition among learned Men, that the leaves of Vines that grow in some places of Hungary, whose Mines afford Gold, are as it were gilt on the lower side, by ascen­ding Exhalations of a Golden Nature: whether this be true or no, I shall not take upon me to determine: but I re­member, that having made enquiry [Page 45] about the truth of it, of a very inge­nious Traveller, whose Curiosity led him to visit heedfully those famous Mines: he told me, that he did not re­member he had observ'd what is re­ported about the Leaves of the Vine: but he knew very well that at Tockay (a place that affords the famousest Wine of Hungary, and indeed the best I have drunk) very many of the ker­nels of the Grapes would appear guilt over, as it were, with leaf gold. To what has been already discours'd, may be added, that since men are not wont to feed upon either Beasts, or Birds of prey, as carnivorous Animals usually are, but upon such as live up­on Grass, or Seeds, or other vegetable substances, and drink nothing but fair water; the noxious exhalations that make vegetables, and water unwhol­some, may by their means have a very bad influence upon Sheep, Cows, Deer, Pigeons and other Animals that seed upon such deprav'd vegetables, and drink such noxious waters; and consequently may be very hurtfull to [Page 46] those men that feed upon such Ani­mals, and may by the deprav'd aliment they afford, determine them to an En­demical Disease, such as that vitiated nutriment is fitted to produce.

Perhaps it will not seem improper to add on this occasion, that 'tis pos­sible that in certain places the latent Minerals may be of such a Nature, as that their Effluvia may, instead of pro­moting, hinder the Production of some particular Disease, whether E­pidemical or Endemical in the Bodies of them that inhabit those Places. For as Physicians observe that the more manifest morbifick causes of some sick­nesses, are quite contrary to those of others, so I think it not improbable, that there may also be a mutual con­trariety, between those latent morbi­fick causes, that are sent up by sub­terraneal Agents. And therefore it need to be no wonder, if some of these should either disable those to which they are Hostile, or should at least work in Humane Bodies a great In­disposition to admit their hurtfull [Page 47] Operations, which methinks those Physicians and Chymists should easi­ly grant, who with a boldness that I do not applaud, prescribe Amulets, wherein Arsenick, or some other poy­sonous Drug is employ'd, as preserva­tives from the Plague, against which, I doubt the chief Succours they af­ford, proceeds from the Confidence or Fearlesness they give those that wear them. But to return to our sub­terraneal Effluvia, since there are di­vers whole Countries, or lesser pla­ces, that are either altogether, or in great part, free from this or that par­ticular Disease; as in several parts of Scotland from Agues, especially if I mistake not Quartans, are very un­frequent, insomuch that a learned Physician answer'd me, that in divers years practice he met not with above three or four, and in several large Re­gions of the East-Indies, notwithstan­ding the excessive heat of the Cli­mate, the Plague is very rare: since (I say) these things are so, it seems not altogether improbable that the sub­terraneal [Page 48] steaws may contribute to this advantage, by impregnating both the Air, the Earth, and the Water, with Corpuscles endow'd with Qualities un­friendly to these Diseases, which seems to be somewhat the more credible, because it has been observ'd that some vast Tracts of Land will neither breed nor maintain venemous Creatures, as is undoubtedly believ'd of the whole Kingdom of Ireland, where I confess I neither did see any alive, nor met with any other that did; for as to Spiders, though they breed in that Countrey, where I have seen many of them, and sometimes even upon Irish Wood, yet they are unanimously believ'd not to be poysonous there: And some Wri­ters tell us, how truly I know not, of some other Countries, to which they affirm the like Privilege to be­long. But there is one instance affor­ded us by Begninus, who travel'd much to visit Mines, which if it be strictly true, is very notable for my present purpose. Dignum admiratione est, says he, quod quamvis in vicinia Hydriae [Page 49] Comitatus Gloriciensis, ubi reperitur copiosè ☿ singulis ferè annis Lues pesti­fera grassatur, illa tamen semper immu­nis ab hac manere soleat, idque viri pro­vectae aetatis se observasse & à majori­bus suis accepisse, mihi sanctè confirmâ­runt. To which I should add the Te­stimony of the Learned Michael Mayerus, who pronounces Mercury to be an Alexipharmacum against di­vers Diseases, and particularly the Plague, if I did not suspect by his way of mentioning this last Disease, that he but borrowed his Encomium of Mercury from Begninus. But howe­ver; what has been related, has invi­ted me to consider, whether there may not be some virtue, as well as some danger, in Amulets of Quick­silver that are by many extoll'd a­gainst the Plague. But this onley up­on the bye.

PROPOSITION III.

I Am very well aware, that di­vers Diseases that extraordinarily invade great numbers of people at the same time; (and were therefore, by the Greeks called Epidemical) may be rationally refer'd to manifest Intemperatenesses of the Air, in point of Heat, Cold, Moisture, or some other Obvious Quality. And there­fore the Proposition speaks but of some Epidemical Diseases, and imputes those it speaks of to Subterraneal Ef­fluvia, not as total, but as partial, and sometimes as principal, Agents in the production of them.

In favour of the propos'd Con­jecture thus explain'd, I shall offer two things to Consideration.

[Page 52]I. And first, it seems not very im­probable, that divers of those Mor­bifick Excesses (especially if they be sudden) that are observ'd in the Air, may proceed from the unusually copi­ous ascent of hurtfull Exhalations that mingle with the Air, and diffuse themselves through it. We are grea­ter Strangers than we commonly take notice of, to the Subterraneat part of the Globe we inhabit: and if I had leasure, and thought it ne­cessary, I could shew, that there are a great many odd and surprizing things to be met with in the Struc­ture and disposition even of those parts of the Earth, that lie but a lit­tle way beneath the surface of it, and partly have been, and partly may easily enough be, actually pene­trated by the industrious Labours of men. And as for the deeper Sub­terraneal Regions, we are so much more unacquainted with them, that we are scarce fit so much as to con­jecture, how far they extend, or [Page 53] what kind of Materials they contain, and what is the gross, and (if I may so speak) the Mechanical Fabrick of the greater Masses, whether solid or fluid, they consist of: And least of all can we determine what Motions, whether periodical, or others, these Masses, or other Portions of deeply lodg'd Matter, may have.

On such grounds as these, I con­ceive▪ it possible, that, among the many and various Effluviating Bodies, that the terrestrial Globe may con­ceal in its Bowels, there may be some, whose reeks ascending plentifully in­to the Air, may occasion in it an ex­cess of Heat, Cold, Moisture, thick­ness, or some other manifest Quali­ty. So that sometimes (not to say many times) even those manifest Intemperatenesses of the Air, to which an Epidemical Disease is wont to be wholly imputed, (though perhaps not very justly) may in part proceed from Subterraneal Bodies; for I elsewhere shew, that these by their Conflicts, or Mutual Actions on [Page 54] one another, may excite great and sudden Heats, and on that account send up such copious Steams into the Atmosphere, as may produce there sudden and excessive Heats, Light­nings, Thunders, &c. And I shall now add (what perhaps will appear somewhat strange) that I think sudden and unseasonable Refrigera­tions of the Air, may proceed from the action of Subterraneal Bodies up­on one another: for Tryal purpose­ly made has inform'd me, that there are certain Minerals, whereof some may be employed in their crude Sim­plicity, and the other requires but a slight Preparation, such as it may have in the Bowels of the Earth; which Minerals being put together, will produce by their Reaction an intense degree of Cold, not onely as to sense, but when examined by a seal'd Weather-glass.

The Changes of the Air that produce Epidemical Diseases are sometimes so great and sudden, that they cannot, in my Opinion, with [Page 55] probability be imputed to the acti­on of the Sun, or the Moon, (which are causes that act in too general, and too uniform a way, to have those particular and anomalous Effects at­tributed to Them;) as probably as they may be to Subterraneal Bodies, that often act with more suddenness and impetuosity, and without any regularity, at least that is known to us. The difference we find in Sea­sons, that bear the same name, and should be alike in temperature [...], is oftentimes very great, and sometimes also very lasting. It is proverbially said in England, that a Peck of March Dust is worth a King's Ransom: So unfrequent is dry Weather during that Month, in our Climate. And yet in some years, and particularly the last, 'twas a rare thing to have a shower either in March, April, or May, sometimes in the Month last na­med, there are Heats greater than in the Dog-days of that same Year; though usually here in England, di­vers Mornings of that Month are [Page 56] cold, and some of them frosty. And now and then I have observ'd in the same Months and Days, at no great distance from one another, that the Weather has been sultry hot, and has also produc'd a great Snow. We have seen Summers like that which is remember'd for the Siege of Colchester, that for almost the whole Season, where more dark and rainy, than several Winters have been ob­serv'd to be. To which purpose I remember, that when I was about to write the History of Cold, I was fain to watch almost a whole Winter to find two or three frosty days, to make an Experiment or two I had need of, that requir'd not a Cold that was either lasting or very intense. But Instances of this kind are so obvious, to those that are at all heedfull Observers, that I may safely pass them by, and inculcate that the Sun being in the same Signs, at the same Times of the Year, it does not appear, how He should produce so great a disparity [Page 57] of the temperature of the Air in Seasons of the same denomination; (as the Winters or the Summers of dif­fering, and yet perhaps immediately consecutive, Years.) And therefore I do not so much wonder, that ma­ny Learned Writers fly to Astrology for an account of these irregular Phae­nomena, and ascribe them to the in­fluences of certain Stars; notwith­standing what divers eminent Philo­sophers, and some great Astronomers too, have said to prove the vanity of Judiciary Astrology.

I shall not now stay to discuss the Question, whether the Stars have a­ny influence distinct from their Light and Heat: because, my Opinion a­bout it being somewhat peculiar, I have discoursed of it in a Paper by it self. But this I shall now say, that the fixt Stars being but general, and (if I may so speak) indefinite Agents, almost unimaginably remote from us, 'tis nothing near so likely that such Effects as (besides that they happen very suddenly and irregular­ly) [Page 58] are oftentimes confin'd to a Town, or some other narrow Com­pass, should be produc'd by certain Stars: as that they should be so by Subterraneal Bodies, which are near at hand, of very various natures, and subject to many irregular and diffe­ring Motions, commixtures, reacti­ons, and other alterations. I have known a great Cold in a day or two invade Multitudes in the same City, with violent, and as to many Per­sons fatal Symptomes; when I could not judge, (as others also did not) that the bare coldness of the Air could so suddenly produce a Disease so Epidemical and hurtfull: and it appear'd the more probable, that the cause came from under ground, by reason that it began with a very trou­blesome Fog.

That there may be many Subter­raneal Bodies, which by their com­mixtures may produce a sudden Heat, will be easily granted by those that know, (what I elsewhere purposely make out) that there are Subterra­neal [Page 59] Menstruums; and are acquainted with Chymical Operations, such as the great effervescence made, when Oil of Vitriol is put upon filings of Iron, or Spirit of Niter upon But­ter of Antimony; to which I might add many other of the like kind that I have tryed, as when Spirit of Niter is put upon filings, either of Iron, Copper, or Tin, or upon crude Quicksilver; which I shall content my self to have nam'd, because I have another Instance that comes clo­ser to our present purpose. For whereas I have shewn above, that there is in many places great store of Marcasitical matter beneath the surface of the Earth, and sometimes very near it; I shall now add that I have purposely tryed, that putting a little Spirit drawn from Niter, (with which Salt the Earth in many places abounds) or a litle Oil of Vi­triol, upon powder'd Marcasites (which being hard Stones are more difficultly wrought upon, than many other Subterxaneous marcasitical Bo­dies [Page 60] of a looser texture) there pre­sently ensued a strong reaction be­tween the Liquid and the Solid Bo­dies, whereby was produc'd much heat, not without visible fumes, and Strongly Scented, though not visible, Exhalations. And such kind of Odorous Effluvia were e­mitted, upon the putting a little Spi­rit of Salt upon our Powder'd Mar­casites. And because Sulphur is a mineral that (either pure, or copi­ously mix'd with others) is to be plentifully met with in the Bowels of the Earth, and in many places burns there, I shall add, that I have found acid Spirit of Sulphur (made the common way) to work sensibly upon marcasitical matter, hard e­nough coagulated. An experienc'd German Chymist relates, that in some parts of his Country he met with Vitriol Stones, or Marcasites, that, by the action of mere com­mon Water resting a competent time upon them, will grow so hot as to enable the Liquor to retain a [Page 61] sensible Heat, when it had pass'd a pretty way from them. And, as I elsewhere shew, that many Ac­cidents may occasion the breaking out of Waters, or the change of their course in Subterraneal Places; So, that common Water may produce in a very short time considerable degrees of Heat in Mineral Bodies, may appear by mixing with two or three pounds of fine Powder of common Brimstone a convenient quantity, (for now I remember not well how much I took) of filings of Iron, for this mixture being tho­roughly drench'd with common Wa­ter, did in a short time grow intense­ly hot, and send up such a thick Smoke as good quicklime is wont to doe, whilst men Slake it with Wa­ter.

It is observable to our present purpose, what account was given me by a Domestick of mine, that liv'd in the North part of England, of a certain Mineral Groove which he had often occasion to resort to: for, [Page 62] when I ask'd whether the Damp that place was molested with, did frequently recurr; he answer'd me, that at the time he was there it would annoy the workmen, (if they did not take good care of themselves) more than once in one day. And by Enquiries that I made of others that were conversant in Mines, I learn'd, that in divers places they were molested with Damps, that came not at stated Periods, but irre­gularly; sometimes with much grea­ter, and sometimes with far lesser, Intervals between them: the times of their duration being also not sel­dom unequal. So that, supposing such noxious Effluvia to be plenti­fully emitted from the lower parts of the Soil, it need be no wonder, that an Epidemical Disease should be rise in this or that particular Town or part of a Country, without sprea­ding much farther; and that it should begin suddenly in places where it was not expected: for, be­sides that these swarms of Effluvia, [Page 63] being produc'd by casual concourses of Circumstances, may oftentimes be excited, and invade this or that place, without giving the Inhabitants any warning, besides this, I say, 'tis not always necessary that these noxious Effluvia should be generated just un­der the places they molest, since the motion of the Air, especially when the Wind sits favourably, may suffice to carry them to the Town or o­ther place that feels their ill effects: and yet they may seem to be almost confin'd to those places; sometimes because the neighbouring places are not inhabited enough to make their ill qualities taken notice of; but more frequently because, by being dif­fus'd thorough a greater tract of Air, they are more and more disperst in their passage, and thereby so diluted (if I may so speak) and weakn'd, as not to be able to doe any notori­ous mischief.

And here I Consider too, that 'tis not always necessary that the harm that is done by these morbid [Page 64] Constitutions of the Air, should pro­ceed onely or precisely from these Subterraneal Exhalations we are speaking of, by virtue onely of their own qualities, which they bring with them from under ground. For 'tis very possible, that these Ef­fluvia may be in their own nature either innocent enough, or at least not considerably hurtfull, and yet may become very noxious, if they chance to find the Air already im­bu'd with certain Corpuscles fit to associate with them: for, though these sorts of Particles were perhaps neither of them a-part considerably hurtfull, yet there may from their Combinations result Corpuscles, of a new and very morbifick nature.

This may be somewhat illustrated by considering, that the spirituous steams of Salt-peter are not wont sensibly to work on Gold, nor yet the spirituous Parts that the Fire rai­ses from Sal-armoniac; and yet when these two sorts of Particles convene, there results from their Coalitions [Page 65] certain Corpuscles of a new nature, that compose the Liquor Chymists call Aqua Regis; which by its fret­ting quality corrodes and dissolves Gold. By Analogy to this we may conceive, that sometimes the Subter­raneal Effluvia may find the Air al­ready impregnated with such Cor­puscles, that by associating them­selves therewith they may compose Corpuscles far more capable, than themselves were whilst apart, of ha­ving ill Effects upon the Mass of Bloud, or some determinate Parts of Humane Bodies, and consequently of produceing Diseases there.

And this Instance may appear the more apposite; because it may be said, that as, though Silver and Gold, and Diamonds and Rubies, &c. be put together, and Aqua Re­gis be pour'd upon them, it will leave all the rest uncorroded, and fall onely upon the Gold; so the newly produc'd Corpuscles that I have been speaking of, whether brea­thed in with the Air in Respiration, [Page 66] or carried up and down by the Bloud, or other Liquors of the Body, may pass by other parts of it without do­ing them any sensible harm, and at­tacking this or that determinate part, produce there some Disease such as the fabrick and situation of that part peculiarly dispose it to be affected with.

And I shall add on this occasion, that in our Hypothesis we may render a probable reason, why in some E­pidemical Diseases, some persons may escape much better than other, that seem likely to be, at best, as obnoxious to them, without a re­course to the peculiar Constitutions of the Bodies of differing Persons; for it may be conjectur'd, that the noxious Corpuscles that infest the Air, may (especially in windy wea­ther) be very unequally disperc'd through the Air, and many fly in far greater or lesser numbers with­in equal spaces of Air; and conse­quently the Persons, that have the ill luck to be in the way of the more [Page 67] numerous swarms of morbifick Cor­puscles, may be much more prejudi­ced by them than others, though of weaker constitutions, who happen to be attaqu'd but by few of them.

On which occasion, I remember, that a great many Trees in some Land that belongs to me, having been suddenly much endamag'd by a wind, that was not able to doe it by it's bare strength; I had the curio­sity to view somewhat heedfully a Tree that stood in the Garden, and perceiv'd that all the considerable mischief was done to that side of the Tree, which respected the corner whence the hurtfull Wind blew, the Leaves of the other side continuing fresh and verdant, as being by the other part of the same Tree fenc'd from the Wind: and it was farther observ'd, that even the expos'd side of the Tree was not every-where endamag'd; for there were divers parts, where the Leaves continued sound and green, though neighbou­ring Leaves were some more, some [Page 68] less (for all that were prejudic'd were not totally) blasted: the sound Leaves and the discolour'd being so odly mingled, that I conjectur'd the cause of the mischief to have been this; that some Arsenical or other corrosive or poisonous Exhalations, being suddenly emitted from the Subterraneal parts into the Air, were by the Wind they chance to meet with there, hurry'd along with it, and blown against the Bodies that stood in it's way, moving in the Air, like Hail-shot discharg'd out of a Gun, here in a closer, and there in a more scattering order, so that as more or fewer of them happend to fall upon the same Branch or Leafe, they left more, or less marks of their passage, by destroying the texture and colour in the Leaves or parts of them they chanc'd to beat upon. And this may possibly be the cause of some of those sudden and sometimes fa­tal Effects, that I have known in some places the people talk much of, complaining, that such a one had his [Page 69] Eyes, or his Face, or onely one side of it blasted, by a malignant Wind, of which I thought I saw an Exam­ple in a Domestick of my own, whilst in such a Wind he was riding after me, who (thanks be to God) had no such mischief done me.

But the Vulgar have entertain'd such strange Conceits and Stories a­bout these Blastings, on which ac­count some of them say that Men are Planet-struck that the fabulous things mingled with those that are possible, have made intelligent Persons reject them all.

One thing more I shall take notice of in favour of our Hypothesis, which is, that it well agrees with what has been observed, not without some wonder, of the very short duration of some Epidemical Diseases, in cer­tain Times and Places. For this may proceed from hence, either that all the Morbifick Expirations ascended into the Air almost at once, or at least within a short time, and so were easily spent, that is by diffusion or [Page 70] dispersion so weakned, as to be dis­abled from doing much mischief: or else the Subterraneal Commotion that produc'd them may pass on from one place to another, and so cease to afford the Air incumbent on the first place, the supplies necessary to keep it impregnated with noxious Exhalations. And it agrees well with this Conjecture, that sometimes we may observe certain Epidemical Diseases to have as it were a progres­sive Motion, and leaving one Town free pass on to another. Of which some Observations that I have made, encline me to think, that if Physi­cians would heedfully mind it, they might take notice of several In­stances.

One thing more may be added, as consonant to our Hypothesis; namely, that sometimes an Epidemi­cal Disease ceases in this or that place, almost as sudden as it invaded, or at least in a much shorter time than Physicians expected. For according to our Hypothesis it may well happen, [Page 71] that after one sort of Exhalations, whose peculiar Qualities make them Morbifick, have deprav'd the Air incumbent on a particular place; there may by a new or farther Commotion of Subterraneal Bodies, be sent up into the Air store of Ex­pirations of another kind, which meeting with those that formerly impregnated it, may either precipitate them, and so free the Air from them; or by other operations on them, and sometimes even by Coalitions with them, so alter their nature as to dis­able them from doing any farther mischief.

This I shall illustrate, if not confirm, by that very remarkable Phaenomenon that is yearly observ'd at Grand Cairo in Aegypt; for, (though I know not whether or no the Corpuscles that produce it arise from under Ground, the affirmative part of the Question being not improbable) it appears, that by the intermixture of adventi­tious Corpuscles, with the formerly Pestilential Air, 'tis so alter'd and [Page 72] corrected, that within one day or two, if not within a lesser compass of time, there is a stop put to the progress of the Plagues; that in that favoura­ble time of year, namely about the middle of Summer, scarce ever misses of raging in that populous City: and, which is more admirable, these sana­tive Corpuscles (if I may so call them) operate so powerfully, that of those that are already seiz'd by that fatal­lest of Diseases, the Plague, few or none die of it, after once these Antidotal Particles have sufficiently impregnated the Air. I confess so great and sudden a change is very wonderfull, and I should scarce think it credible, if I had not had the means and curiosity to enquire about it of divers persons, some of them very intelligent, that either curiously vi­sited, or also made some considera­ble stay in, that great City; and found them agree in the main about the truth of the matter of fact; which is much confirm'd to me by so eminent a Testimony as that of the [Page 73] learned Prosper Alpinus, who for seve­ral years practis'd Physick in Grand Cairo, and as an Eye-witness delivers what he relates more authentically, as well as more particularly, than a­ny I have met with. And, though he endeavours to give several reasons of this strange and sudden cessation of the malignity of the Plague, yet I doubt they are not sufficient for so wonderfull an effect; unless we take in some new Exhalations, that then impregnate and correct the Air.

And we shall scarce doubt of the great interest these have in the ef­fect produc'd, if we give credit to what the recentest Writer I have met with of Voyages into Egypt, has lately publish'd about the annual Pestilence at Grand Cairo, a City he much frequented. This Authour, in the account he gives of the pre­sent state of Egypt, relates that a lit­tle after the middle of our June (and usually upon the very seven­teenth day) there begin to fall to­wards the last quarter of the night, [Page 74] near the morning, certain drops of a kind of Dew, which causes the River to be fruitfull, and purifies the Air from all the Infection of Cam­sims, by which I presume he means the Pestilence: for after some lines interpos'd he subjoins, The Drops or Dew purifies the Air, for as soon as it falls the Plague ceases to be mortal, none dies of it; the Air is whole­some, all Distempers cease, and if any person grows sick, he never dies.

And then, he adds, This Dew gives life to every thing; and when it falls upon the Wheat, it causeth it to continue many years without corrupti­on or Worms, and is far more nourish­ing than that Corn on which it never falls. For this cause they never house the Corn of the Grand Seignior in the Barns, till this Dew is fallen upon it, that it might keep the longer with­out Worms.

As well this Conjecture, as some other things deliver'd here and there in this Paper (about the Salubrity of the Air,) may probably gain the [Page 75] more credit, if I here subjoin what I learn'd by inquiry from a very inge­nious Gentleman, who was owner of one or more of the Mines, that af­ford the Phaenomenon I am to men­tion. Which is this, That in the Tin-mine Countreys in Devonshire, it sometimes happens, (as perhaps I may have elsewhere noted to another purpose,) that upon a sudden, a Spot of ground, and that not always nar­row, will be as 'twere blasted by the ascending hurtfull Fumes; inso­much that not onely the Grass, Fern and other more tender Vegetables, will be turned black, and as it were burnt or scorched up; but now and then Trees also, without excep­ting Oaks themselves will be blasted and spoil'd by the powerfull Opera­tion of these subtil and poisonous Ef­fluvia.

It will probably be here expected, that among the Epidemical Diseases that our Hypothesis derives from Subterraneal Effluvia, I should par­ticularly treat of the cause of Pesti­lential [Page 76] Fevers, and the Plague it self. But, though some such Fevers may not improbably be in great part im­puted to the noxious Expirations of the Globe we inhabit; yet, as to the true Plague it self, I freely con­fess I am at a loss about it's Ori­gine.

The sacred Writings expresly teach, that some Plagues, and par­ticularly that which in David's time swept away in three days 70000 Persons, have been in an extraordi­nary manner inflicted by God. And to me it appears either scarce possible, or far more difficult than those that have not attentively enough conside­red the matter, are wont to think it; To deduce the abstruce Origine, strange Symtomes, and other odd Phaenomena of some Plagues that are recorded in History, from merely Corporeal Causes.

On the other side, it seems unphi­losophical, and perhaps rather seems than is very pious, to recur with­out an absolute necessity to Superna­tural [Page 51] Causes, for such Effects as do not manifestly exceed the power of Natural ones: though the particu­lar manner of their being produc'd, is perchance more than we are yet a­ble clearly to explicate. And I think it the more questionable, whether all Plagues are Supernatural Exertions of God's Power and Wrath against the Wicked, because I observe that Brutes (which are as well uncapable of moral Vice, as moral Vertue) are yet oftentimes subject to Mur­rains, such as may without incongru­ity be lookt upon as the Pestilences of Beasts. And 'tis the less likely, that these sweeping and contagious Maladies should be always sent for the punishment of impious men, be­cause I remember to have read in good Authours, that, as some Plagues destroy'd both Men and Beasts, so some other did peculiarly destroy Brute Animals, of very little con­sideration or use to Men, as Cats, &c.

[Page 52]Upon these and the like Reasons I have sometimes suspected, that in the Controversie about the Origine of the Plague, namely, Whether, it be Natural, or Supernatural; neither of the contending Parties is altoge­ther in the right: since 'tis very pos­sible, that some Pestilences may not break forth, without an extraordi­nary, though perhaps not Immedi­ate, interposition of Almighty God, provok'd by the Sins of Men: and yet other Plagues may be produc'd by a Tragical concourse of merely Natural Causes.

But though the difficulties that incumber each of the opposite Opi­nions, keep me both from Dogma­tically asserting, that All Plagues have a Supernatural Origine; and from denying that Any have it: yet, to say something on such an oc­casion, though I can speak but ve­ry hesitantly, I shall venture to add, that, whether or no the true Plague be said to descend to the Earth from a higher Sphere than that [Page 53] of Nature; yet its Propagation and Effects are (at least for the most part) carry'd on mainly by a malignant disposition in the Air; without which some Plagues could never have been so catching as they were, nor so suddenly mortal; and that in divers Pestilences this malignant Disposition in the Air, may probably be in great part imputed to some kinds of Subterraneal Expirations, I am prone to think; and that chiefly up­on two Accounts.

The first thing that induces me to this Conjecture, is, that not any of the several Causes to which the Plague is wont to be imputed seems to me to be sufficient. Those that fetch it from the malevolent aspects and influence of the Celestial lights, besides that they suppose some things very difficult to be prov'd, have re­course to Agents too remote, too general, and too indeterminate, to be acquiesc'd in as the Causes of such particular Symtomes and Phaenomena, as oftentimes accompany Pestilences. [Page 54] And as for those other Sects of Phy­sicians that confidently derive the Plague, some from Internal Putre­faction, and others from excessive Heats, noisome Stinks, Corrupt a­liments, and such other Celebrated Causes; though each party alledges plausible Reasons for its own opini­on, yet their objections against their adversaries are much stronger than their arguments are for themselves. And the Learned Diemer-broeck, though his own Hypothesis seem to be more Theological than Philoso­phical, has much enervated the Ar­guments brought for the several opi­nions lately nam'd, and by him dis­sented from.

The Reasons he employs to refute all the receiv'd opinions about the Origine of the Plague, except his own, are divers of them worthy of so learned a man; to whom, though I had leisure to transcribe them, I should refer the Curious: my pre­sent design being onely to deliver some few things that seem more fa­vourable [Page 55] to my Conjectures, than to his Opinion, and were suggested to me, partly by my own Thoughts, and partly by the informations, that, to examine those Thoughts, I pro­cur'd by consulting some uncommon Authours, and asking Questions of great Travellers and Navigatours. By this means I came to learn, that di­vers great Countries are usually free from the Plague, that according to the vulgar Hypotheses, ought to be as much subject to it, if not more, than England, France, Italy, and those other parts of Europe and Asia, where that fatal Disease rages from time to time in the parched Regions of A­frick, to which the Excessive Heats would make one expect, that the Plagues should make far more fre­quent visits than to our temperate European Countries; Leo Africanus informs us, that some parts are so sel­dom afflicted with that dreadfull Disease, that it usually spares the In­habitants 29, or 30 years together. And he expresly records, that in Nu­midia [Page 56] it self, (if I much misremem­ber not the Countrey's name, not­withstanding the raging heat of the Climate, the Plague is wont to be pro­duc'd but once in a hundred years. Our Purchas' s Phil­grimage, lib. 6. cap. 13. Purchas informs us that in the Land of Negro's it is not known at all. And to omit what some Travellers and Naviga­tours relate of Japan, as if it were seldom or never invaded by the Pesti­lence; I do not remember that in New England, which contains a great extent of Land, though I have had both Curiosity and opportunity to inquire after the Diseases of that Countrey, I ever heard the English take any notice of the Plague, since their setling there above three­score and ten years ago. And as for the East Indies, Sir Philibert Vernatti, a Virtuoso of great fame and authori­ty at Batavia where he resides, in his ingenious Returns to the Queries sent him by the Royal Society (of Naturalists) answers thus to the fif­teenth. [Page 57] [ Pestis morbus est Indiarum Incolis incognitus] The Plague is a Disease unknown amongst the Indians. And of the Countries that lie yet more remote, as the great Empire of China, and the Kingdoms of Tun­quin, and of Cochinchina, that great Traveller Alexander de Rhodes, who spent 30 years in those parts, affirms, that the Plague is not so much as spo­ken of there. And yet the same Jesuit does, upon grounds probable enough, estimate the number of the people of China alone to be two hun­dred and fifty millions; [a number I take to exceed by far that of all the Nations of Europe.] Now when I consider, how vast Tracts of Land are compriz'd in those Countries, some of which the Plague does not at all, and others but exceeding un­frequently, invade; this Immunity seems to me very unfavourable to most, if not all, the opinions receiv'd among Physicians, as also that of Diemerbroeck himself who derives the Plague from a Supernatural Cause, [Page 58] the wrath of God against the sins of men. For in Regions of such extent, and divers of them very populous, which are seated under very differing Climats, and which are some of them inhabited by Nations, that make war with numerous Armies, fight bloudy battels, leave heaps of unbury'd Bo­dies expos'd to the putrefying heat of the Sun; are sometimes forc'd, as well as others to live upon very un­wonted and unwholsome foods; that worship stocks and stones, and beasts, and some of them Devils, whom they know to be such; that are at least as guilty as Europeans, of Assas­sinats, Poisonings, Rapes, Oppressi­on, Sodomy, and other crying Sins: in these Regions, I say, 'tis not ima­ginable but that great Intemperatures of the Air, especially, in point of Heat, Stench of dead Bodies kill'd in fights, unwholsomness of Aliments, malevolent aspects of Celestial Bo­dies, high provocations of the divine Justice, and in short, all the Causes, to one or other of which the seve­ral [Page 59] parties of Physicians are wont to refer the Plague, should be wan­ting any more than in our Europe; and yet the Plague which is presum'd to be the Effect of one or other of those Causes, is not here observed to be produc'd.

I know that it may be said, that the Historical things I have been re­citing, do not onely oppugn the se­veral receiv'd Opinions of Physici­ans about the cause of the Plague, but disfavour my Conjectures too. But if this be said, I desire it may also be consider'd, that my Judg­ment about the Plague consists of two Parts; One, that 'tis exceed­ing difficult to assign the true and adequate Cause of the Origine of the Pestilence; and the Other, that whatever be the Cause of its First E­ruption, its Propagation and divers of its Symptomes, may be probably enough refer'd to the depravation of the Air by Subterraneal Steams, and their Effects. If this be duly con­sider'd the Historical Observations [Page 60] will appear not to overthrow the First member of our Hypothesis, but rather to confirm it: and 'tis upon this account that I have men­tion'd them in this place. And as to the Second member it may be said, that since in the East Indies and the other Countries, I have nam'd, as privileg'd from this raging Disease, it is not observ'd to break out: as it cannot be said that Subterraneal Ef­fluvia do in those Countries promote the Propagation of it; so it can­not be prov'd that they could not doe it, incase the Plague were begun by other Causes. But in regard I think it not improbable that some­times the Plague is not onely fomen­ted but begun by noxious Expirati­ons of the Terrestrial Globe, I shall add that this supposition, though I confess it be somewhat disfavour'd by some of the lately mention'd Ob­servations, yet is not absolutely in­consistent with them. For First, it may be said that some of the Coun­tries I speak of, may be destitute of [Page 61] those noxious minerals to which we impute some Plagues, it holding true in Minerals as well as in Plants. Non omnis fert omnia tellus, and to omit what I have not without some wonders observ'd, of the Limits of differing sorts of Mines and Mineral Veins in very bordering parts of the same tract of Land, I cannot but here take notice, that though Sul­phur be in many Countries usually found, and that in plenty where there are other Metalline Veins, in­somuch that Chymists make it one of the three Principles of all Metals, yet in the Mines of England more strictly so call'd, I do not remember I ever met with so much as an Ounce of Native Sulphur, and I could not find by divers Mineralists, of whom I purposely ask'd the question that they had met with any among the various Mines they had frequented. It may also happen that there may be hurtfull Minerals in a Countrey, and yet not capable of often pro­ducing or promoting Pestilences [Page 62] there, even upon moderate Earth­quakes. For 'tis possible that these Orpimental or other Noxious Mine­rals may have their Beds or Veins lying so deep in the Earth, that they are not ordinarily able to send up Effluvia, strong and copious enough to make a Pestilential depravation of the Air, and even in lesser Earth­quakes the commotion or agitation of the ground, especially if the Earth-quakes proceed (as one may suspect that divers of them do) from the sudden fall of ponderous Masses in the hollow parts of the Earth and the shakings of the ground thereby produc'd, and sometimes spreading far, may not reach so far downwards as much to affect these very deep Mines, and yet some other more violent Earthquakes, may af­fect even these; upon which ground one may give some tolerable account why the Plague in some parts of A­frick has been observ'd to rage but once in thirty or once in an hundred years; for there may be periodical [Page 63] Paroxysms, if I may so call them, or grand and vehement Commotions in Subterraneal Parts, though men have not yet, for want of sufficient Lon­gevity or Curiosity observ'd them. On which occasion, I remember that a late judicious French Histori­an recounts that in part of the last age, and part of this, a very perni­cious Disease of the nature of a Colick raign'd in France every tenth year for a long tract of time. And the Experienc'd Lib. 2. P. M. 323. Pla­terus relates, that at Basil, where with great success he practis'd Physick fifty six years, the City was afflicted with furious Plagues once about every tenth year for seventy years together, of each of which Pestilences he gives a par­ticular account in his usefull observa­tion. It may also farther be said, that those Exhalations in the East Indies, &c. that would otherwise be pestiferous, may be corrected by o­ther Expirations that may be either of benign nature, or of such a na­ture, [Page 64] as though noxious in them­selves, may fit them by combining with those that would be pestife­rous to disable them to be so, as I elsewhere observ'd out of Beguinus, that a Countrey abounding in veins and masses of Cinnabar, which is the Ore of Quicksilver, was preserv'd from the Plague, when the neigh­bouring Regions were wasted by it; and I shall illustrate this matter some­what farther by taking notice, that though Corrosive Sublimate be so mischievous a Mineral Composition, that a few grains may kill a man, yet the fumes of this combin'd with those of Crude, common Quicksil­ver, which are themselves unwhole­some enough, make Mercurius dul­cis, which is a mixture so innocent, that being well prepar'd, and well administred, it is both safely and usefully given even to Children.

If what has been said will not suf­fice, I shall propose another possible way of accounting for the immuni­ty of some Countries from the [Page 65] Plague. For one may conceive that in such Regions the Soil, and other assisting Causes may constantly produce in the Air such a Constitu­tion as is found in the Air of Egypt, during the time of the increase, and overflowing of Nile, which usually lasts every year for several weeks, for during this time the Air is so an­tipestilential, that not only the Plague does not make a new Eruption; but is either wonderfully check'd or quite suppress'd in those houses that it has already invaded, so that its mortal infection reaches no farther, and that it may not be thought in­credible that some Countries may have, if I may so speak, an antido­tal Nature, in reference to some per­nicious Evils, I shall represent that there are some whole Countries which are privileg'd from producing Vipers, Toads, and other venemous Creatures, as is vulgarly known con­cerning Ireland, where I could ne­ver see any such, nor find by Enquiry of either the Natives, or English In­habitants, [Page 66] that they had met with any in that Kingdom, where 'tis an uncontroll'd tradition, that if Poyso­nous Creatures have been carefully brought there from other Parts, they have died almost as soon as they came thither. There are some other Islands to which a like hostility to vene­mous Animals is ascrib'd: and as it seems not inpossible that some Coun­tries should have a Soil that so im­pregnats the Air as to make it sup­press or quite enervate many differ­ing sorts of Poysons, so others may by their Constitution be qualify'd to master or resist poisonous Expi­rations or wandering Corpuscles that elsewhere are wont to produce the Plague. And this may suffice for the first thing whereon we ground our Hypothesis.

The Second thing that invited me to the above propos'd Suspicion or Conjecture, is, That it affords a not improbable account of some considerable things, relating to the [Page 67] Production and Phaenomena of the Plague.

(1.) As First, 'tis observ'd that sometimes the Plague breaks out, when there has not preceded any such immoderate distemper of the Air, or any casual Enormity capa­ble of producing so great and ano­malous an Effect. Nay, which is more, it has been observ'd, that ve­ry great and unusual intemperatenes­ses of the Air have several times hap­pen'd, and divers notable and threat­ning Aspects of the Stars have been noted by good Writers without be­ing follow'd by the Plague. The celebrated De abditis rerum caus. lib. 2. c. 13. Fernelius re­lates, that near the time he writ this Observation, that Year, which of all those that had pass'd in the memory of Man, was all the World over the most im­moderately hot, and was yet most healthfull. And the same Authour reports the Plague to have begun in the midst of Winter, and to have gone off in Summer, and that seve­ral [Page 68] times ardent Summers have been altogether free from the Plague: which I also have noted to be true. Johannes Morellus observes, that in his Countrey after a dry Winter, and wherein the North Wind reign'd, though it were succeeded by a most temperate and healthfull Spring, yet this brought in the Plague, and that, when the North Wind was predomi­nant and the Air pure and sincere. Which I the less scruple to believe, because I observ'd something very like it in the Constitutions of the Air, that preceded and accompany'd the dreadfull London Plague that broke out in the year 1665. Which Phaenomena much disfavour their Opinion that impute the Plague to the excesses of the manifest Qualities of the Air; but are agreeable to our Hypothesis, since by what has been formerly deliver'd, we may ga­ther that Noxious Subterraneal Fumes may be suddenly, and without any warning belch'd up into the Air, and, by depraving it, produce [Page 69] fatal Diseases in many of those that are constantly surrounded by it, and draw it in, almost every moment, with their breath.

Of the deadly Hurtfulness of di­vers Subterraneal Expirations, at their first Eruption, there are many Histories extant in approv'd Au­thours: And we have observ'd In­stances of that sort, in the Times and Countries we live in. But, because all Poisonous, and even mortal, Ex­halations are not therefore truly Pe­stiferous, but may, like many other Poisons, kill the Persons they im­mediately invade, without qualify­ing them to infect others; I shall add a Passage out of that Excellent Historian ‘ Monsieur de Mezeray who relates in the life of Philip de Va­lois, that the Plague that happened in France in the Year 1346. was so contageous and destructive, that scarce a Village, or even a House, escap'd uninfected by it. He adds, that this Pestilence, than which none had been observ'd more furi­ous [Page 70] and spreading, began two years before in the Kingdom of Cathay, by a vapour that was most horribly stin­king, which brake out of the Earth like a kind of Subterraneal fire, con­sum'd and devour'd above 200 Leagues of that Countrey, even to the very Trees and Stones, and infected the Air in a wonderfull manner. From Cathay, say's he, it pass'd into Asia and Greece, thence into Africk, afterwards into Europe, which it ransack'd throughout.’ O­ther Instances, of Pestilences begun by noxious Subterraneal Fumes, I have met with in good Au­thours; See Diemer­broeck de Peste, lib. 1. cap. 8. but cannot now re­call the Particulars to mind, and therefore shall pass on to the second Observation.

(2.) In the next place then; whereas 'tis noted by diligent Obser­vers, that there is a wonderfull di­versity in several Countries, and even in the same Countrey at several distant times, of those raging Dis­eases, that Physicians agree in calling [Page 71] the Plague, (whence it happens that such Medicins or Methods of curing as are in one Plague succesfull, as Phlebotomy, Purging, &c. do often­times in another prove dangerous, if not mortal) whereas (I say) this great variety has been observ'd in Plagues; it may be fairly accounted for, by the great number and diversi­ty that has been actually found, or may be reasonably suppos'd, in the numerous Minerals, and other Bo­dies that nature has lay'd up in the Subterraneal Regions: especially if we consider, that the number of such Bodies may be much increas'd and diversified, by the various com­binations which may be made of them, not onely by casualties, but by the action of Subterraneal Fires, and aestuaries, and menstruums, such as I have elsewhere shewn to be lodg'd beneath the turf or superfi­cies of the Earth. And the ascen­ding Corpuscles of those Mineral Bo­dies, being most of them solid and subtile, may produce in the Bloud; [Page 72] and so in the Body, far more odd, and violent Symtomes, than the pec­cant Humours that use to beget or­dinary Diseases. Which may be one reason, and perhaps the chief, why the ancient Heathens, and Hip­pocrates himself, acknowledg'd in Pestilential Diseases [...], some­what of Divine, surpassing ordinary Nature.

What these Mineral Substances are, whose steams produce such odd and dismal Symtomes, I think exceeding hard to determine. Yet, if I were to name one sort, I should perhaps think the least unlikely to be Orpiment. For, of the Poysonous Minerals we are acquainted with, I know not any of which there is grea­ter quantity in the Bowels of the Earth; especially taking that name, in the latitude allowed it, by those skilfull men, that make three sorts of it, viz. Yellow, Red and White Or­piment, divers of whose mischievous Effects seem to agree well enough with the Symtomes of some Plagues, [Page 73] and may be guessed to have at least a considerable interest in the pro­duction of them. But yet, to speak candidly, I do not think that these Minerals are the causes, even of all those Pestilences whose efficients may come from under the Ground: For several reasons, and some drawn from Experience, make me think that the Subterraneal Regions have many kinds of very mischievous fossiles, of which Physicians, and e­ven Chymists, have no knowledge, and for which they have not any distinct names; and that the various associations of these, which Nature may by Fire and menstruums make under Ground, and perhaps in the Air it self; may very much in­crease the number, and variety of hurtfull Matters, and also heighten their hostility to Humane Bodies: as I think may be argued from the fac­titious White Arsenick that is com­monly sold in Shops, which though usually made of Orpiment, by the addition of so innocent a Body as [Page 74] common Salt, (which is found in great plenty under Ground,) is ob­serv'd to be far more poysonous than Orpiment it self. And I remember that a skilfull Chymist, having in my presence tasted some prepar'd, and, as was thought, somewhat cor­rected Arcenick; was quickly inva­ded by such Symtomes, as he thought would presently kill him. But, through God's blessing, I quickly put him out of danger, though not out of pain, by early prescribing him store of Oil of sweet Almonds, and something made of Lemmons, that I chanc'd to have by me: But to return to what I was saying; Sanda­rach seems to be, but Orpiment whose yellow Colour is deepn'd to Redness: and native Arsenick, (for I have seen such a thing, though it rarely comes into England,) seems to be little other than pale or white Orpiment. And indeed in Hungary, all three may be found not far from one another in the same Mine; As I learn'd by Inquiry from an obser­ving [Page 75] Eye-witness, by whose means, and of another Chymist, divers Na­tive Orpimental Minerals (to say nothing of Realgar) because it is a Factitious combination of Orpiment and Sulphur, came to my hands. And as this sort of Fossiles comprizes more numerous and various ones, than is vulgarly noted, so the very noxious effects of the Effluvia of Orpiment, are not unknown to di­vers Physicians: and the Learned Sennertus gives a particular Senn. M. P. E. vi. p. 65. instance of it in a Painter, who upon opening a Box where Orpiment, which men of his Profession use as a Pigment, had been long kept, had his face all swell'd, and was cast into fainting Fits. And as White Arsenick is of a more piercing and corrosive nature, so it were not difficult to shew out of the Writings of eminent Physicians that its effects have divers times pro­ved very hurtfull, and sometimes mortal. When but externally worn in Amulets, especially if the Pores [Page 76] of the Skin were open by exercise and sweat; and the nature of the Symptomes produced seems to con­firm our Hypothesis, since the Per­sons that wore these Arsenical Amu­lets were affected, some with great anxieties about the Heart, some with inflammation, some with burning Fevers, some with exulceration of the Breasts, so some with Pussles like those of the Plague, and these were sometimes black, as if made with a Caustick: most Patients were affected with great weakness and faintness, &c. as if they had swallowed Poison; and of one young Man 'tis recorded, that ha­ving heated himself in a Tennis­court with an Amulet upon his Breast, the virulence of its Corpus­cles made him fall down stark dead upon the Spot. And 'tis a conside­rable Circumstance in these Obser­vations, that several Patients were cur'd of the Symptomes that seem'd to be Pestilential ones by the same Remedies that are Alexipharmacal [Page 77] against the Plague, whence it may also be made probable, that the Plague it self many times is a natu­ral, though a dreadfull and anoma­lous Disease, since its Effects and Symptomes so much resemble those of acknowledg'd Poisons, and have been cur'd by Antidotes effectual against other Poisons.

I have not time to mention what I have my self try'd and observ'd a­bout the bad effects of Orpiment, and its kinds. But I remember, that enquiring of an ingenious Man, who sometimes visited a Mine which was known to abound with Orpimental Fossils; he answer'd me, that when he walked over the neighbouring Grounds, he found himself much disorder'd, especially in his Thorax by the Effluvia, and that the Mine-men and Diggers were subject to a malignant anoma­lous and dangerous sort of Fevers, though he said he was apt to im­pute, I know not how truly, some part of their obnoxiousness [Page 78] to it, to their drinking too much strong Wine. But though 'tis pro­bable the Effluvia of Orpimental Bodies may have a great interest in several Plagues, yet, I strongly sus­pect that many others may proceed from the steams of such Subterraneal Bodies as are not yet distinctly known to us; and possibly have their Effluvia variously combin'd, either beneath or above the surface of the Earth. I say above; because I have several times, and that with­out heat, combin'd separately invi­sible fumes of differing kinds, into manifestly visible ones in the free and open Air.

And that the Subterraneal Efflu­via may produce effects, and there­fore probably be of natures, very uncommon, irregular, and if I may so speak, extravagant, may appear in those prodigious Crosses that were seen in our time, viz. in the Year 1660. in the Kingdom of Na­ples, after an eruption of the fiery Mountain Vesuvius: of which Pro­digies [Page 79] the Learned Kircherus has gi­ven an account in a particular Dia­tribe. For these Crosses were seen on Linen Garments, as Shirt­sleeves, Womens Aprons, that had lain open to the Air, and upon the expos'd parts of Sheets; which is the less to be admired, because as Kir­cher fairly guesses, the mineral va­pours were by the texture that be­longs to Linen [which consists of threads crossing one another for the most part at or near right Angles] easily determin'd to run along in al­most streight lines, crossing each o­ther, and consequently to frame Spots resembling some one, and some another kind of Crosses. These were extremely numerous in several Parts of the Kingdom of Naples: in­somuch that the Jesuit that sent the Relation to Kircher says that he himself found thirty in one Altar­cloth, that fifteen were found upon the Smock sleeve of a Woman, and that he reckoned eight in a Boy's Band: also their colour and magnitude [Page 80] were very unequal, and their fi­gures discrepant, as may appear in many Pictures of them drawn by the Relatour: they would not wash out with simple water, but requir'd Soap; their duration was also une­qual, some lasting ten or fifteen days, and others longer before they disappear'd. And these Crosses were found not onely upon Linen Gar­ments expos'd to the Air, but upon some of those (belonging to Altars) that were kept lock'd up in Chests (to which possibly they might have access by the Key-holes, or some un­heeded chinck.) To which strange Phaenomena if I had the leisure to add some others that I have met with in Agricola, and other appro­ved Authours, whose Relations my memory doth not now serve me particularly to cite; I presume it would appear yet more probable that Subterraneal Effluvia may now and then be of a very A­nomalous nature, and produce strange effects, and among them [Page 81] variety of Pestiferous ones in the Air.

But, to add this upon the bye: though I fear Physicians will not be able to discover all the subterra­neal Bodies whose Effluvia produce or contribute to the Plague: yet I do not think it impossible that by diligent observations and trials, sa­gacious Men may discover divers of them; and perhaps Antidotes a­gainst them.

And though the business of this Paper be to treat of the Causes, not the Remedies of the Plague; yet I love Mankind too well, to suppress on this occasion an Obser­vation, that, by God's blessing, may in some cases, save the lives of many. In the late great Plague that swept away so many thousands at London, there staid in the City an Ingenious Physician, that was bred by the Learned Diemerbroeck, (whose Book De Peste, I prefer to any I have yet read of that Disease.) This Doctour (whose name I am [Page 82] sorry I have forgotten) hearing that I was desirous to receive an ac­count of the Plague from some in­telligent Eye-witness, and having soon after some occasion to pass near the Place in the Countrey where I then resided, was pleas'd to give me a visit, and a rational account of the main things I desired to know; and when I inquired about his method of Cure, after he had told me that he had twice had the Plague himself, whereof he shewed me some effects; he added, that after many and various trials, he perceiv'd that abundance of his Patients died, after the Bubos, (Carbuncles) or Pestilential Tu­mours appear'd; because upon a little refrigeration of the Body by the Air, and oftentimes by the very fear that disheartened the Patient, the Tumours would suddenly sub­side, and the Pestilential Matter re­coiling upon the Vital Parts, would quickly dispatch the fatal work. Wherefore he bethought himself of [Page 83] a method, by means of which he as­sur'd me, he had not lost one Pa­tient of very many he treated; if he could but, as he usually did, by good Alexipharmical, and Cordial Remedies, enable and excite Nature to expell the peccant Matter into a Tumour; for then he presently clapp'd on an appropriated draw­ing Plaster, which would never suffer the Tumour to subside; but break it, or make it fit for opening, and thereby give Nature a conve­nient vent, at which to discharge the matter that oppress'd her. This Plaster 'twill easily be thought I was desirous to know; and he told me 'twas a Chymical one, and that 'twas no other than the Magnes Ar­senicalis of Angelus sala, whose de­scription, because the Book where­in 'tis found, is in few hands, I have here annext. If this prove as suc­cessfull in other Plagues, as it did to those that us'd it in that of London; there will be just cause to admire and praise the benignity of Divine [Page 84] Providence, which in a poisonous Mineral, that probably does often­times concur to produce the Plague, has laid up a remedy for it.

By the same motive (Philanthro­py) I am induc'd to add on this oc­casion, that having had some op­portunity to oblige an ancient and very experienc'd Physician, to whose care was committed a great Pesthouse, where the Contagion was so strong, that he lost three Physicians that were to be Assi­stants to him, and three Chirur­geons of four that were to be sub­servient to him; I disir'd to learn of him, if he counted it not too great a secret, what Antidote he us'd to preserve himself from so vio­lent and fatal an Infection. This re­quest [Page 86] he readily granted, but with­all told me, that his method would not seem to me worth mentioning, if I were one that valu'd Medicines by their Pompousness, not their U­tility. For, besides ardent Prayers to God, and a very regular Diet, his constant Antidote was onely, to take every Morning fasting a little Sea-salt dissolv'd in a few spoonfulls of fair Water; which he made choice of, both because it kept his Body soluble without purging or weakning it, and for other Reasons which I must not now stay to set down. I know this Medicine may appear a despicable one; but yet in my Opinion it ought not to be de­spis'd, after such Experience as I have related has recommended it. For I think it desirable, that notice be taken of all Remedies, that have been found by good Trials, not bare Conjectures or uncertain Re­ports, available against the Plague. For, since Pestilences, as we have lately noted, are exceeding various [Page 87] in their kinds, 'tis very possible, and not unlikely, that their Appro­priated Remedies may be so too. And therefore I would not easily lay aside every Medicine, that this or that Learned Physician may speak slightly of, or even may de­clare that he has found it unsuccess­full against the Plague; since the same Medicine may be available in a Pestilence of another kind, in which perhaps the Remedies com­mended by the Physician we speak of, will be found inefficacious.

This Consideration forbids me to pass by what happen'd to me in the great London Plague above-men­tion'd; namely, that a very Lear­ned Physician having once recom­mended to me an Herb little noted in England, as a most effectual and experienced Antidote against the Plague, I caus'd it to be cultivated in a Garden (as I still do every year;) and when the Pestilence ra­ged most, having some of it by me, made up with a little Sugar in the [Page 88] form of a fine green Conserve, I sent it to two infected Persons, who, by the Divine Benediction on it, both of them recover'd. But having made but those two Trials, I dare not ground much upon them onely; though I usually keep the Plant growing in a Garden, partly because both the Taste and Colour; one or other of which in most An­tidotes is offensive, are in this plea­sant; and partly because some little Experience has invited me to be­lieve the Commendations that I have found given of it, against the Bitings of venomous Creatures: whereof I remember a notable In­stance is recorded by Petrus Spehrerius of a In Observat. no­bil. apud Schen­kium, l. 7. Observ. Med. Tit. de venenis ex animalibus. Roman, who having with his Staff pierc'd or crush'd a Viper, that he took to be dead, had so strong a Venom trans­mitted along the Staff, that the in­suing Night he had a very great In­flammation in both his Lips, to [Page 89] which superven'd an exceeding Ar­dent Fever and strange Tortures; from all which Serianus Pacyonius, a noted Physician that was call'd to him, free'd him as it were by Mira­cle, by the Juice of Goats-rue, or as others call it Galega, that grew co­piously in that Place. It may with­out disgust be taken somewhat plentifully, (and so it ought to be) in its entire substance as a Salad; or else one may give its Conserve, its Syrup, or, which is better, its Juice newly express'd.

(3.) It likewise agrees with our Hypothesis; that sometimes the Plague ceases, or at least very nota­bly abates of its Infectiousness and Malignity, in far less time than ac­cording to the wonted course of that ravenous Disease, Physicians did, or rationally could expect. For sometimes it may happen, that, though the Temperature or Intem­perateness of the Air continues the same, the matter that afforded the Pestiferous Exhalations may be ei­ther [Page 90] spent under ground, or so al­ter'd by combination with other subterraneal Bodies, or by some of those many Accidents that may hap­pen, altogether unknown to us, in those deep and dark Recesses. And if once the Fountain of these noxious Effluvia be stopt, so that those that are in the Air cease to be recruited, the Wind and other causes may in a short time dissipate them, or at least dilute them with innocent Air, so far, as to keep the Disease they pro­duc'd from being any thing near so mischievous as before. And here I consider, that it may several times happen, that, though the Minerals that emit the hurtfull Expirations, remain where they were under ground, and be not considerably wasted, yet their fatal Effects may not be lasting, because the Effluvia were generated by the conflict of two or more of them, which vehe­mently agitated one another, and sent up fumes, which ceas'd to as­cend, at least in great plenty, when [Page 91] the Conflict and Agitation ceas'd. As, I have try'd that by putting good Spirit of Salt upon Filings of Steel or Iron in a conveniently shap'd Glass, there will be made a great conflict between them, and without the help of external Heat, there will be sent up into the Air store of visible Fumes of a very Sul­phureous Odour, and easily inflam­mable, which copious elevation of Fumes will lessen or cease, as does the tumultuous agitation that pro­duc'd them. And so likewise, if you pour Aqua fortis upon a conve­nient proportion of Salt of Tartar, there will be at first a great ebulli­tion produc'd, and, whilst that con­tinues, store of red and noisome Fumes will be elevated, but will not long outlast the commotion of the mixture, whose active parts will in no long time combine into a kind of nitrous Salt, wherein the noxious parts of the Menstruum are as it were pinion'd, and hinder'd from evapo­rating or ascending, though really [Page 92] they retain much of their pristine nature, as I elsewhere shew.

It may also happen, that soon af­ter that commotion of subterraneal Matter, which sent forth pestiferous Exhalations, a more intense degree of subterraneal Heat, or perhaps the same latent Fire, extending it self farther and farther, may force up Fumes of another sort, that being of a contrary nature, may be, if I may so speak, antidotal against the former; and by precipitating them, or combining with them, may disa­ble them from acting so mischievous­ly as otherwise they would. To countenance which I shall tell you, that I have sometimes purposely made Distillations, in which one part of the Matter being, after the operation ended, put to the other, there will ensue a sudden and mani­fest conflict between them, and sometimes an intense degree of Heat. And that mineral Exhala­tions, though otherwise not whole­some, may disable pestiferous Efflu­via, [Page 93] may be gather'd from what I lately noted about a Countrey, which abounding with veins of Cin­nabar, was, probably by their ex­pirations, preserved from the Pesti­lence. And our Hypothesis will per­haps appear somewhat the more pro­bable, if we reflect on what I lately mention'd of the sudden check, that is almost every Summer given to the Plague, which at that time is wont to reign at Grand Cairo. For since 'tis generally observ'd and complain'd of, that Morbifick Cau­ses doe their work much more effec­tually than Sanative ones. It seems very probable that Exhalations as­cending from under-ground into the Atmosphere, may be capable of pro­ducing pestilential Fevers, and the Plague it self, since those Corpuscles that impregnate the Egyptian Air upon the swelling of the Nile, are able to put a speedy stop, not one­ly to the contagiousness, but to the malignity of the Plague, even when 'tis assisted by the Summer [Page 94] Heat, which at Grand Cairo is wont to be excessive.

But having insisted perhaps too long on this Egyptian Pestilence, I shall onely add, by way of Illustra­tion of the Conjecture that invited me to mention it, that the accession even of Expirations that are not themselves wholsome, may sometimes serve to correct the Air, and put a sudden check to an Epidemical Dis­ease. For Corpuscles of differing kinds may by their Coalitions ac­quire new Qualities, and each sort of them lose some of those they had before: as, suppose there wander'd in the Air a great many Effluvia, which by their determinate shape and bulk were apt to corrode or ir­ritate the Lungs, or the Membranes of the Brain, &c. as those of Nitre are to corrode Silver; it may hap­pen that another sort of Reeks, though in their own nature un­wholsome, may, by associating themselves with the first sort, and composing with them Curpuscles of [Page 95] new qualities, abolish or much wea­ken the noxious ones they had be­fore, in reference to this or that part of the Humane Body. Though the Spirits of Salt-peter will readi­ly corrode Silver, yet if you add to them (as for some purposes I am wont to do) about half as much or less of the spirituous Particles of common Salt, (which yet are cor­rosive enough, and will fret asun­der the parts of Iron, Copper, An­timony, &c.) there will emerge a Body that will not at all corrode pure Silver.

PROPOSITION IV.

THE Product of my first En­deavours to bring credit to the foregoing Proposition, appear­ing to have miscarry'd, when I came to send to the Press the things I had written about it; that at least what can be preserv'd of it may not be lost, I shall substitute in stead of it the following Account.

At the entrance of my Discourse I observ'd that the Term new Dis­ease was much abused by the Vulgar, who are wont to give that Title to almost every Fever, that, in Au­tumn especially, varies a little in its Symptoms, or other Circumstances, from the Fevers of the foregoing [Page 97] Year or Season. And therefore I declared, that by new Diseases I meant onely such, whose Symptoms were so uncommon, that Physicians themselves judged them to deserve that appellation; Such, for instance, as the Sudor Anglicus or Sweating Sickness; that Disease which the learned Wierus and others call in Dutch Die Varen; an unheard-of Disease describ'd by Ronseius, that in the Year 1581 invaded and de­stroy'd many in the Dukedom of Lunenburg; to which many Physici­ans add the Rickets, and others ge­nerally the Lues Venerea. Having clear'd the Terms, I next consider'd whether there were really any new Diseases properly so call'd, and gave some reasons to suspect that some Diseases, which among Physicians themselves have pass'd for New, were extant before in rerum natura, though not in the Countrey wherein even the learned judg'd them to be new. And I intimated, that to examine this Suspicion throughly, 'tis not safe [Page 98] to acquiesce in the Books of Phy­sicians onely; but 'tis fit to consult the Writings of Geographers, whe­ther ancient (among whom I particu­larly recommended Strabo) or Mo­dern, together with the Relations of Historians, Navigators and other Travellers. And here I inquired, without determining any thing, whether the Lues Venerea be, as most Physicians are wont to suppose a Disease wholly new, or onely new to our European World, and brought hither from some African or other remote Region, where it may be probably suspected to have long been Endemical.

But taking it for granted, with the generality of Physicians, that some new Diseases are to be admitted; I advanced to consider some of the Causes, to which they may be impu­ted; And to give some reasons, why I do'nt acquiesce in their Opini­on, though very general, that derive them onely or chiefly from the va­rying influences of the Heavenly [Page 99] Bodies. For the most powerfull of those, namely the Sun and Moon, act in too general and indeterminate a way, to afford a sufficient account of this affair. And as for the other Lights, the fixt Stars, besides their being universal and indefinite agents, their scarce measurable remoteness makes it justly questionable, whether they have any sensible Operation upon any part of our Bodies, save our Eyes. And, though I deny not that great intemperateness of the Air, as to the four first Qualities, as Heat, Cold, Driness and Moi­sture, are wont (not over justly) to be call'd, may dispose mens Bodies to several great Distempers, and may also be concurrent causes of those we are speaking of: yet neither can I acquiesce in these, when I consi­der how much more frequently they happen, than new Diseases do; and that their action, though various, is too general and indeterminate to perswade me, that they can be the adequate causes of effects so rare and [Page 100] anomalous▪ as Diseases odd enough to deserve the Title of new.

But now; the Subterranean Re­gion of our Globe, besides that it is always near us, abounds with va­riety of noxious Minerals, and pro­bably conceals great quantities of differing sorts of them, that are yet unknown to us. And A Discourse of Subterraneal Steams as they affect the Air. since we have elsewhere proved, that there want not causes in the Bowels of the Earth, to make great and ir­regular, and Sometimes sudden Con­fluxes, Conflicts, Dissipations, and other considerable Changes, amongst the Materials, that nature has plen­tifully treasured up in those her se­cret Magazins. And since, in ma­king out the three former Proposi­tions, we have manifested, that the Subterraneal parts of the Globe we inhabit, may plentifully send up Noxious Effluvia of several kinds in­to the Air; it ought not to seem im­probable that among this Emergent variety of Exotick and hurtfull [Page 101] Steams, some may be found capable to disaffect Humane Bodies, after a very uncommon way, and thereby to produce new Diseases; whose du­ration may be greater or smaller, ac­cording to the lastingness of those Subterraneal causes, that produce them. On which account it need be no wonder, that some new Dis­eases have but a short duration, and vanish not long after, there appear­ing the Source or Fomes of the Mor­bifick Effluvia, being soon destroy'd, or spent: whereas some others may continue longer upon the Stage, as having under ground more settled and durable causes to maintain them. Which last part of the Observation may be illustrated by what happen'd in Calabria; which Province, though it have been observed to have acqui­red, within these two or three ages, the faculty of produ­cing Manna upon cer­tain Trees C. Magnenus de Manna, cap. 9. Dic amabo, Altomari, cur ante trecentos annos nullum Manna fuit in Oenotria; jam cer­té aderant Pagi ibi­dem urbésque vicinae neque fefellisset curio­sam Incolarum soler­tiam. &c. 15. ante 240. annos nullum Mannae Calabreasis in Autoribus vestigi­um est.; yet this great change, though sudden enough, had [Page 102] it seems such stable causes, as well as of great extent, that it hath lasted several scores of years, and continues in that Countrey to this day.

I am not ignorant that the whole Doctrine propounded in the four Propositions about the Insalubrity of the Air, is not at all comfortable ei­ther to Patients or Physicians: But important Theories deserv'd to be inquir'd into, and, if true, to be de­liver'd though we could wish they were untrue. And judicious men rather thank than blame those that have given us account of latent or unsuspected, though perhaps irreme­diable causes of Diseases and of death; or have recorded the Histories of some Poysons, whereof the true An­tidotes are yet unknown. Uncom­mon Notions about Diseases may serve to inlarge the Physicians mind and excite his attention and curiosi­ty: and, besides that they may keep [Page 103] him from too obstinately persisting in the use of receiv'd Medicins, though unsuccessfull, upon a Suppo­sition that the Disease can have no other causes, than those wont to be assign'd it by Classick Authours: be­sides this, I say; I do not despair, but that either the sagacity or for­tune of this inquisitive age, or at least of Posterity, may by the bles­sing of God be happy enough to find proper Remedies, even for those Diseases that proceed from Subterra­nean Effluvia, when once by proper Signs they shall be distinctly disco­ver'd; (Of which power of appro­priated Remedies) I have known some Instances, as to the very bad Symptoms produc'd by Antimonial and some other Mineral Fumes.

Some of the Points discours'd of under the fourth Proposition, were of affinity enough to Paradoxes to have need of being illustrated or confirmed by Observations and Ex­periments. And therefore having accidentally retriev'd some of this [Page 104] last nam'd sort, I shall venture to subjoin them as a Specimen, though without Transitions or Applications, but just as I found them thrown to­gether, in one loose sheet, wherein I lighted on them. But it is time to conclude with the recital of the promised Experiments. Which I would immediately do, but that I hold it fit to premise, by way of In­troduction to them, that I hope the Things hitherto discours'd will ap­pear much the more probable, if we shall prove by Experiments, that which seems much less likely than a­ny thing we have above deliver'd; namely, that Metals completely for­med and malleable may be elevated into the Air, and that perhaps with­out any great violence of Fire, in the form of Exhalations and Vapours; the singly invisible Corpuscles still re­taining their Metalline nature. This at least, as to some Metals, I have endeavour'd to prove in another Tract, [entitl'd a Paradox about the Fuel of Flames.] But because that [Page 105] Discourse was never publish'd I will here set down two or three Experi­ments, (not mention'd, that I re­member in it.) Which I do, the more willingly, because it may be a Thing of no small moment in Phy­sick, if it be shewn that Fixt and solid Bodies, such as Metals are, may by art be reduc'd into such mi­nute Corpuscles, that without loo­sing their nature and all their Pro­perties, they may become parts of Fumes, or perhaps of invisible Va­pours, or even of Flame it self.