An essay of the great effects of even languid and unheeded motion whereunto is annexed An experimental discourse of some little observed causes of the insalubrity and salubrity of the air and its effects / by the Honourable Robert Boyle ...

A Short Supplement TO THE ESSAY OF THE GREAT EFFECTS OF Even Languid and Ʋnheeded LOCAL MOTION.

THAT I may not be altoge∣ther wanting to the Expec∣tation that may have been rais'd, by a Passage in the Advertise∣ment prefix'd to the foregoing Essay; I shall here subjoin some Particulars, which perhaps will not be unwel∣come to the Readers, that occurr'd to my remembrance, whilst I was,

with a transient Eye, reviewing the Heads of the past Discourse. But these Paralipomena or Supplements will be but few, not onely because of my want of leasure to review the Tract they belong to deliberately, but also because some Instances, that might be here subjoin'd, may be more opportunely brought in in o∣ther Papers.

To the IIId. Chapter.

THAT the Motion of the Air that accompanies Sounds may be propagated to great Distances, and yet make considerable Impres∣sions on the Bodies it finds there, dispos'd to admit its Action, may be notably confirm'd, by a Phaeno∣menon I have met with, in the lear∣ned Mathematician Borellus, who relates it upon his own knowledge, and not undeservedly magnifies it: which I shall therefore recite in his

own Words.

* 1.1Aderam (says he) Tauromenii Siciliae, quando Aetna mons eruptionem quandam effecerat propè Ennam, urbem fere 30. Mil∣liaria à Tauromenio distantem, tunc vicibus interpolatis eruptiones in∣gentes ignis vorago efficiebat, grandi sono & strepitu, & tunc omnia Tau∣romenii aedificia, tremore concutie∣bantur, in quo Circumstantiam no∣tatu dignissimam observavi: scili∣cet, quòd domus & aedificia quae di∣rectè exposita erant prospectui ejus∣dem voraginis, vehementissimè con∣cutiebantur; reliquae verò domus, quae conspectu voraginis privaban∣tur, satis lentè & leniter tremorem efficiebant.

Upon which matter of fact he thus argues:

Profectò, si hujusmodi tremor factus fuisset à concussione & resilitione soli Tauro∣menitani, omnes domus aequè con∣cussae fuissent, & aequali tremore agitatae, ita ut non possit conspectus voraginis tam insignem & eviden∣tem inaequalitatem tremoris pro∣creare;

igitur necessariò à tremore ejusdem aëris incusso in parietibus domorum liberè percussiones excipi∣entum, agitatio illa efficiebatur. Vi∣deas hinc, (infers he) quanta soni ad 30 milliarium distantiam effi∣cacia sit.

To the Vth. Chapter.

THAT Motion may be propa∣gated far, through Bodies of differing Natures, may be inferr'd from what is mention'd in this Chap∣ter, especially about Earthquakes. But because it may reasonably be suspected, that the Active Matter which produces those stupendious Motions, is dispers'd into divers Places, and may be of considerable Extent, I shall here subjoin, out of the Eloquent Famianus Strada, an Instance, which is much the most memorable to my purpose that I re∣member to have met with in His∣tory;

to manifest to how great an extent a Motion excited in a very narrow compass, perhaps but a very few fathom square, may be propa∣gated through differing Mediums, and one of them as solid as Earth. This famous Historian then, having describ'd a stupendious Work, that had been with great skill and care made by the Prince of Parma, to keep the City of Antwerp, which he closely besieged, from being reliev'd by the River Scheldt (which, though not broad, is deep) proceeds to re∣late, that an Engineer, who was a great Master in his Art, having un∣dertaken to destroy this great Work with a Vessel (which I think we may call a Floating Mine) fraught with Gunpowder, Fireworks, &c. per∣form'd it with so tragical a success, that some Spanish Officers that were present, reckon'd 800. to have been kill'd outright, besides a great num∣ber that were wounded and maim'd. But that Part of the Narrative which comes home to our pre∣sent

purpose, is deliver'd in these Words.

On a sudden the fatal* 1.2 Ship burst, with such a horrid crash, as if the very Sky had rent asun∣der, Heaven and Earth had charg'd one another, and the whole Machine of the Earth it self had quaked. For the Storm of Stones, Chains and Bullets being cast out with Thunder and Lightning, there followed such a Slaughter, as no man, but that actually it happen'd, could have ima∣gin'd. The Castle on which the In∣ternal Ship fell, the Pile-work of the Bridge to St. Mary's Fort, that part of the Naval Bridge next the Castle, Souldiers, Mariners, Commanders, a great number of Cannons, Ar∣mour and Arms; all these this fu∣rious Whirlwind swept away toge∣ther, tossed in the Air, and disperst as Wind doth Leaves of Trees. The Scheldt prodigiously gaping was first seen to discover its bottom, then swelling above the Banks, was even

with the Rampiers, and overflowed St. Mary's Fort above a foot. The motion of the panting Earth N. B. extended its force and fear above nine Miles. [If he means the Miles of that Countrey, or Dutch Leagues, they amount to 36 English Miles.] There were found Stones, and that very great ones, as Grave-stones, and the like, a Mile off the River, struck into the Ground, in some places four Palms.

To the VIth. Chapter.

Observation I.

WHAT is delivered in this Chapter about the Operati∣on of Sounds and Animals, particu∣larly that which is mention'd (Pag. 72.) about the Effect of Musick up∣on Serpents at Grand Cairo, may be not onely confirm'd but exceeded, by a strange Relation that I had from a Person of unsuspected Credit▪

Which Narrative having appear'd to me so considerable, as well to deserve a place among my Adversaria, I shall subjoin that part of it which con∣cerns our present Subject, in the words wherein I find it set down.

Sir J. C. a very candid and judici∣ous Traveller, favouring me yester∣day with a visit, told me among o∣ther remarkable things relating to the East Indies, (which Countries He had curiously visited) that He with divers European Merchants had seen, (and that if I mistake not, se∣veral times) an Indian, who by ma∣ny was thought to be a Magician, that kept tame Serpents of a great bulk. And that when the Owner of them plaid upon a Musical Instru∣ment, these Serpents would raise themselves upright into the Air, lea∣ving upon the Ground but 3 or 4 In∣ches of their Tail, upon which they lean'd for their support. He added, that at the same time that they erec∣ted their Bodies, they also stretcht

and lengthen'd them in a strange and frightfull manner; and whilst they were thus slender, they were taller than He or any man of ordinary sta∣ture. But that which appear'd to Him the most wonderfull and surpri∣sing, was, that they manifestly seem'd to be very much affected with the Musick they heard; insomuch that some Parts of the Tune would make them move to and fro with a surprising agility, and some other Parts of it would cast them into a Posture, wherein they seem'd to be half asleep, and as it were to melt away with pleasure.

To the VIth. Chapter. Pag. 75.

Observation II.

BEcause the Truth even of the principal effects of the Biting of the Tarantula, has of late been pub∣lickly call'd in question, I was glad to meet with an ingenious Traveller,

that in Calabria or Apulia was Him∣self bitten by one of those venomous Insects; and though it were but slightly, yet the Effects He felt in His own Body, and those greater ones He saw produc'd in other Per∣sons, that were more unhappily bit∣ten, brought Credit to the main of what sober Writers affirm of the Symptoms and Cure of that Poy∣son. And the learned, &c.

To the VIIth. Chapter. Pag. 83.

MUCH of what is delivered in this Chapter and elsewhere, a∣bout the Operation of Air or invisible Fluids (whose Motions affect not the Touch) upon Congruous Solids, may be confirm'd by that notable Experiment, which has been publi∣shed in an Elegant Discourse by the learned Morhofius; about a Dutch Wine Seller in Amsterdam, by name Nicolaus Petterus, who, having found the Tone or Note peculiarly

belonging to a large belly'd drinking Glass, Such as the Dutch call Römer, and many here call Rhenish Wine Glasses, would, by accommodating his voice exactly to that Tone, and yet making it loud and lasting, make the Vessel, though not visibly touch∣ed, first tremble and then burst; which it would not do, if the Voice were, though but a little, too low or too high. This notable Experiment has been seen by many Vertuosi, both before and since he publish'd it. And the very ingenious Writer, as he pas∣sed through London, not onely rela∣ted it to me, but very civily offer'd me farther satisfaction, if I could fur∣nish Him with a Römer, which I was very sorry that where we then were was not to be procur'd.

To the VIIIth. Chapter.

Observation I.

IT may add probability to some things deliver'd in this Chapter and in divers other Passages of this Treatise, if I here recount a strange Phoenomenon, that came into my me∣mory whilst I was running over those Parts of this Discourse.

The Phoenomenon, in short, was this. Having met with divers pieces of transparent Glass, which I had rea∣son to think to be of a Texture or Temper very differing from ordina∣ry Glass, I thought fit to try, whe∣ther some of them were not far more springy and brittle than their thick∣ness would make one expect. And accordingly, though I found several wherein the Experiment would not succeed, especially if their figure were not convenient, yet with some others, I had very good success, and

particularly with some that were shap'd almost like the sharper End of the neck of a Retort. For though these pieces of Glass were much thic∣ker than such necks are wont to be, being perhaps 6 or 7 times as thick as common drinking Glasses, yet I more than once made the Tryal succeed so well, that, by obliquely scratching them, or tickling them if I may so speak, on the inside with the head or point of a Pin, they would forceably burst into many pieces in my hand. In which surprizing Phoenomenon, the matter of the Glass seem'd to contri∣bute something to this odd Effect, of so languid a motion, but much less than the Texture, or Tension, it ob∣tain'd by the peculiar way of order∣ing it in the Fire and the Air.

To the VIIIth. Chapter.

Observation II.

TO shew that the Suspicion I mention my self, a little be∣fore the end of this Chapter, to have had, that the breaking of the Stones there spoken of might possibly be produc'd or promoted by some im∣pressions, remaining after the strokes employ'd to force the Stones out of their Beds, was not altogether with∣out ground.

I shall here observe, that it need not seem incredible, that faint strokes and attritions may leave more lasting and operative Motions among the Insensible Parts, even of compact and solid Bodies, than one would readily imagine. For I have several times found, sometimes by Observa∣tions designedly made, and some∣times by undesigned Accidents, that, having caus'd somewhat thin Vessels of Glass, especially Urinals, to be di∣ligently

made clean with Sand mixt with Water, to loosen or grate off the foulness that adher'd to the sides of the Vessel; though the Vessels, af∣ter having been thus made clean, did not appear to have receiv'd the least injury, and would continue very in∣tire perhaps for several hours, yet af∣ter that time they would of them∣selves break with noise, and thereby become unserviceable for the future. But though this happen'd to many Urinals, yet, because to more others it did not, it seem'd probable that the dissilition depended chiefly upon the peculiar texture of the Glass in this or that Vessel, whether acquir'd by a mixture of the Ingredients, that was not uniform enough or made in a due proportion; or else by the too hasty refrigeration of the Vessel, es∣pecially if it chanc'd, as is not very unusual, to be cool'd more hastily in one part than another.

To the IXth. Chapter. Pag. 110.

Observation I.

BEcause there are divers Gems; particularly those Transparent ones that are Red or Blew, that are much harder than Iron or steel, it may much strengthen the Proof of our 8th Observation, if I here relate that a Jeweller to a great Princess an∣swer'd me, that when he polish'd Sa∣phyrs, Rubies, and some sorts of o∣ther hard Gems, upon his Mill, they would seem when attrition had made them very hot, to be all on Fire, like so many little Coals: And that each of them had the light it afforded ting'd with a Colour proper to the Stone; so that the Ruby gave a Red Light, the Saphyr a Blew, &c. And I remember that inquiring of a skilfull Cutter of Diamonds and Polisher of Gems, whose Customer I had been, about some Conjectures I had concerning things belonging to his Profession, he

answer'd me that sometimes, when he polish'd certain Stones, especially Rubies, that were pretty large and perhaps not thick, he could plainly perceive that the Stone gap'd at and near the Edge, as if it were begun to be crack'd; which sign admonish∣ed him to make haste to slacken the Motion of the Mill, lest the Stone should absolutely burst; which if it did not he could not perceive any Flaw in it when it was throughly cold, but, which was strange, it appear'd as entire as ever. He added, in con∣firmation of what he had said of the intense Heat that Gems would some∣times acquire by Attrition, whilst they were in polishing, that having lately given by this means too great a degree of Heat, to an Oriental Topaz (which sort of that Gem is very hard,) it crack'd upon the Mill, in so much that one part of it quite separated from the rest, and spoil'd the Stone in the capacity of a Gem; as a Proof where∣of he had laid it aside for me, and would needs make me accept it, as

a curious, though not an usefull, thing.

To the IXth Chapter.

Observation II.

TO confirm what has been said in the 8th Observation, to shew that slow and insensible Inte∣stine Motions of the Parts of a Bo∣dy that seem quiescent, may be ve∣ry operative, chance afforded me a notable Instance, which was this. I had, to preserve a Liquor from which I expected a curious Experiment, in∣clos'd it in a strong Vial, to whose neck a thick Glass Stople was but too exquisitely adapted. This Vessel I set upon the Edge of a Window, in a high and secure place, that it might not be mov'd. There it continu'd many Months, or, if I misremember not, above a Year. And the Liquor was of such a nature, that if any Body had, though but for a few Moments,

taken out the Stople, I could easily discover it. But after all this while, one day that I was sitting in my Clo∣set, at a good distance from the place in which the Vial stood, I heard a loud and brisk noise, almost like the report of a Pistol, and then perceiv'd that something came rolling to my Feet: I hastily took it up, and, found it to be the thicker and larger part of the Stople of my Vial, which of it self had flown off, leaving the remai∣ning part so closely and strongly ad∣justed to the Neck, which serv'd it for a kind of Socket, that I could by no means pull it out thence. At this Accident I was not a little sur∣priz'd, considering the thickness of the Solid Glass, and that it had stood so long unmov'd, and that the big∣ger and heavier part of the Stople broke off from the other with such violence, and was carry'd from it by invisible motors to so great a di∣stance. Which seem'd the more strange, because there was no sha∣king nor treading in the Room, that

could put the parts of the Glass into Motion, there being no Body present but my self, who was sitting quietly and studying.

To the IXth Chapter.

Observation III.

TO confirm what I have in the eighth Observation and else∣where deliver'd about the latent Mo∣tion of Parts that may be in a Body not onely quiescent but solid, I shall here add a strange Instance, which was afforded me by a Diamond, be∣longing to an ingenious Merchant of that sort of Gems, who brought ma∣ny fine ones out of the East Indies. For having at the Diamond-Mine it self, purchas'd amongst other Stones that grew there, a rough Diamond that he valued at about a hundred pound, and had well considered when he bought it; coming to look over his purchase again once

more, about Ten Days or a Fort∣night after, he was much surpriz'd to find, to his great loss, that this Diamond had of it self crack'd in se∣veral places, and so became of little or no value, but as 'twas a Rarity: and indeed I could not without won∣der, see so fair and hard a Stone so oddly spoil'd with Clefts, that seem'd to penetrate so very deep, that 'twas guess'd 'twould not be very difficult to pull the parts of the Stone asunder. And on this occasion he told me, that he had admir'd this Accident at first, much more than he did afterwards. For complaining of it to divers Mer∣chants and Jewellers, that he met with in those Parts; he was told, that, though it seldom happen, yet 'twas no such wonderfull Accident; The like misfortune having befallen others as well as him.

Notes

• * 1.1

  Borel. de vi Percussionis. Prop. CXI.
• * 1.2

  Famian. Strad. de Bello Belg. Dec. 2. lib. 6, vel 7.