far as divers Earthquakes have done but that the fire passes through some little subterraneal clefts or channels or hidden conveyances from one great Cavity or Mine to another yet 't is not improbable but that the vehemently tremulous motion does oftentimes reach a very great way beyond the places where the explosions were made Since though Seneca would confine the extent of Earthquakes to two hundred miles yet observations made in this and the last Century warrant us to allow them a far greater spread The Learned Josephus Acosta affirms that in the Kingdom of Peru in the year 1586 an Earthquake reached along the shoar of the Pacifick sea 160 Leagues and adds that sometimes it has in those parts run on from South to North 300 Leagues And in the beginning of this our age Anno Dom. 1601 good writers relate a much larger Earthquake to have happened since it reached from Asia to that Sea that washes the French Shoars and besides some Asiatick Regions shook Hungary Germany Italy and France and consequently a great part of Europe And if that part of the Narrative be certain which relates that this lasted not much above a quarter of an hour it will be the more likely that this Earthquake shook great Tracts of Land beyond those places to which the fired matter passing from one cavity to another could reach in so short a time As you will the more easily guesse if you try as I have done that in trains of Gunpowder it self the fire does not run on near so swiftly as one would imagine But though I have been in more Earthquakes then one yet since they were too sudden and too short to afford me any considerable observation I shall say no more of them but proceed to take notice that oftentimes the motion of a Coach or Cart that passed at a good distance from the place that I was in has made the buildings so sensibly shake that I could not but wonder that so great a portion of so firm and sluggish a body as the Earth could by a cause that seemed very disproportionate to such an effect be made to tremble it self and manifestly to shake firm buildings that were founded on it And this observation made me the more inclinable to give credit to their Relations who tell us that in a calm night the march of a troup of horse may be felt by attentive Scouts watching at a great distance off by the shake that the ground receives from the trampling of the horses though I formerly suspected much and do yet a little that the impulse of the air conveyed along the resisting surface of the ground might mainly contribute to the effect that is ascribed onely to the motion of the soil Before I advance to the Second Member of this Chapter it may not be impertinent to note that in peculiarly disposed bodies and especially in Organical ones a very languid motion may have a far greater effect than it could produce by a bare propagation of it self For it may so determine the motion of the Spirits or other active parts of the body it works on as to make multitudes of them act as if they conspired to perform the same motions As when a ticklish man by having the pulp of one's finger passed gently along the sole of his foot or the palm of his hand has divers muscles and other parts of his body and face put into preternatural or unusual motions And most men by being lightly tickled with the end of a feather or straw within their Nostrils have their heads and many parts of their bodies put into that violent Commotion wherein Sneezing consists And I remember that having for some time been by a distemper from which God was graciously pleased a while after to free me quite deprived of the use of my hands it more than once hapned to me that sitting alone in a Coach if the wind chanced to blow a single hair upon my face in the Summer-time the tickling or itching that it produced was so uneasy to me 'till by calling out to a footman I could get it removed that though I could well bear it as long as I was wont to do when having the use of my hands I could relieve my self at pleasure yet if I were forced to endure the itching too long before any came to succour me the uneasiness was so great as to make me apprehend falling presently either into Convulsions or a Swoon But 't is time to proceed to the second Member of this Chapter 2. Others there are that cannot believe that Local motion especially if it be languid can be propagated through differing Mediums each of which save that wherein the Motion is begun must they think either repell or check and dead it To these I shall recommend the Consideration of an Experiment I remember I made before some Learned men in our Pneumatick Engine For having caused a large and thick glass Receiver to be so blown that it had a glass button in the inside of that part which upon the Engine was to be placed upwards I caused a Watch to be suspended by a little Silverchain fastned to that button by as slender and soft a body as I thought would be strong enough to support my watch and then the Glass being cemented on close to the Receiver to prevent a Commerce between the Cavity of it and the Air the watch that hung freely near the middle of the Cavity of the Receiver made it self to be heard by those attentive Listners that would hold their ears directly over the suspended watch whose motions were thereby argued to have been propagated either through the included air or along the string to the concave part of the Glass and through the whole thickness of the Glass to the convex part and thence through the interposed air to the Ear. And this mention of watches minds me of what I often observed in a small striking watch that I have worn in my pocket For when it struck the Hours and in some postures when the balance did but move I could plainly feel the brisker motions of the Bell and sensibly the languid ones of the balance through the several linings of my Breeches and some other interposed soft and yielding bodies and this though the watch as I said was small and the balance included in a double case and though the outwardmost were of what they call Chagrine and the innermost of Gold which I therefore mention because that closest of metals is observed more to dead sounds and motions than harder metals as Silver Copper and Iron That Motion may be propagated through differing Mediums may seem the more probable by the shakings that are often felt by men lying on beds that stand in rooms close shut when loud claps of thunder are produced perhaps at a great distance off in the clouds And whether it will be fit to add to this Instance that which you have lately met with in the III. Chapter
in the production of divers difficult Phaenomena of nature that are wont to be referred to less genuine as well as less intelligible Causes FINIS AN Experimental Discourse Of some UNHEEDED CAUSES OF THE Insalubrity and Salubrity OF THE AIR Being a Part of an intended Natural History of AIR LONDON Printed by M. Flesher for Richard Davis Bookseller in Oxford 1685. THE Preface HAving heretofore had occasion to draw together under certain Heads divers unpublish'd Observations and Experiments of my own and some of other men by way of Memorials for a Natural History of the Air I thought fit by more largely treating of two or three of the Subjects distinctly mention'd in my Scheme of Titles to give a Semplar or Specimen of what may be done upon the other Heads of the designed History Vpon this account I treated somewhat largely of the Salubrity and Insalubrity of the Air as a Subject which for the importance of it to Mens healths and lives I thought deserv'd to be attentively consider'd and have its Causes diligently inquir'd into And having observ'd that among the six principal Causes of the healthfulness or insalubrity of the Air namely the Climate the Soil the Situation of the Place the Seasons of the Year the raigning winds and Contingencies whether more or less frequent and especially Subterraneal Steams having I say observ'd that among these Causes there was one viz. the last nam'd about which I thought I could offer something that I had not met with in the Books of Physicians that treat of it I was thereby invited to set down my Thoughts and Observations by way of Conjectures which I was made to believe would appear uncommon and would not prove useless These Observations and Reflexions I referr'd for clearness and distinctions sake to four Propositions But when I had gone thorough the three first and made some progress in the fourth being hinder'd by divers Avocations to make an end of it I laid by the whole Discourse in a place which I thought a safe one but when afterwards I had some opportunity to dispatch what remain'd I found all the diligence I us'd to retrieve the entire Manuscript unsuccessfull At this surprizing Accident I confess I was somewhat troubled because whatever may be thought of the discursive part of those Papers the Historical part contain'd divers matters of Fact that I did not meet with in Books nor can now distinctly remember and will not perhaps be lighted on by even Physicians or such Naturalists as derive their knowledge onely from them 'T is upon this consideration that having afterwards met with many Papers that belong'd to most parts of the unhappy discourse I thought fit to put them together in the best order I could that I might not loose what might give some light to so important a Subject as the Theory of Diseases And this course I the rather pitch'd upon because before the Papers about the Salubrity of the Air I miss'd two other of my Manuscripts whereof the former contain'd a Cellection of Medicinal things and the second a defence of the Mechanical way of Philosophizing about Natural Things as it respects Religion And I remember'd that having formerly lost a Manuscript I was much concern'd for I purposely made a noise of it whence I suppos'd the Plagiary would conclude himself unable to make it pass for his And in effect the Book was in a while after privately brought back so that I found it laid in a By-place where I had before as fruitlesly as carefully sought it AN Experimental Discourse Of some Unheeded CAUSES OF THE Insalubrity and Salubrity OF THE AIR c. THE sixth and last thing upon which the Salubrity and Insalubrity of the Air depends is the impregnation it receives from Subterraneal Effluvia And though this be a cause not wont to be much heeded by Physicians themselves yet I take it to be oftentimes one of the most considerable in its effects The Effluvia that pass into the Air may be distinguish'd into several sorts according to their respective Natures as has been elsewhere shewn wherefore I shall now only take notice of the differences that may be taken from place and time upon which account we may consider that some of them arise from the Crust if I may so call it or more superficial parts of the Earth and others have a deeper Original ascending out of the lower parts and as it were Bowels of the Terraqueous Globe And to this difference taken from place I must add another perhaps no less considerable afforded by Time which difference relates chiefly to the second sort of Steams newly mentioned Of the Subterraneal Effluvia some are almost constantly or daily sent up into the Air and those I therefore call Ordinary Emissions and others ascend into the Air but at times which are not seldom distant enough from one another and those I call Extraordinary Emissions whether they come at stated times and so deserve the title of Periodical or else uncertainly sometimes with far greater sometimes with far smaller intervals and so may be called fortuitous or irregular But though I thought it might render what I am about to say more clear if I made and premised the two foregoing distinctions yet because in many cases Nature does not appear solicitous to observe them but at the same time imbues the Air with Steams referable to divers Members of these distinctions I shall several times though not always take the liberty to imitate her and consider the Effluvia of the Terraqueous Globe in the more general Notion that they are so I know 't is frequently observed and usually granted that Marrish Grounds and wet Soils are wont to be unhealthfull because of the moist and crude vapours that the stagnating waters send up too copiously into the Air. And on the other side dry Soils are because of their being such generally lookt upon as healthy Nor do I deny that these Observations do most commonly hold true but yet I think that besides what can be justly ascribed to the moist vapours or dry Exhalations we have been speaking of in many places the healthfulness and insalubrity of the Air may be ascribed to other sorts of Effluvia from the Soil than those that act merely or perhaps principally as these are either moist or dry 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 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
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 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 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 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 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 that they had met with any in that Kingdom where 't is 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 Production and Phaenomena of the Plague 1. As First 't is 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 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 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 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
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 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 in their kinds 't is 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 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 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 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 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 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 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 may be gather'd from what I lately noted about a